US 3641733 A
Apparatus for loading and forming envelopes includes a supply structure for a web of plastic envelope blanks, web control means including a web feeding and locating mechanism and a web tensioning mechanism which cooperate to intermittently feed the web along a path of travel, a loading station at which the blank envelopes are loaded, and a forming station at which loaded blank envelopes are simultaneously sealed and cut to size. The web control means feeds a part of each blank envelope to a predetermined location on the path of travel. The feed of the web is then terminated with blank envelopes registered at the loading and forming stations. Loading and forming apparatus operates in timed relation with the web control structure to perform the loading and forming operations when the web is stopped.
Claims available in
Description (OCR text may contain errors)
United States Patent Lerner 5] Feb. 15, 1972  METHOD AND APPARATUS FOR LOADING AND FORMING ENVELOPES AND BLANK ENVELOPE STRUCTURE USED THEREWITH  Inventor: Hershey Lerner, Warrensville Township,
Cuyahoga County, Ohio  Assignee: Automated Packaging Systems, Inc., Twinsburg, Ohio  Filed: June 5, 1970 21 Appl. No.: 43,743
 US. Cl ..53/29, 53/183, 53/372  Int. Cl ..B65b 43/02  Field ofSearch ..53/29, 183
 References Cited UNITED STATES PATENTS 2,272,251 2/1942 Robinson ..53/29 3,393,493 7/1968 Membrino ..53/29 X Primary Examiner-Travis S. McGehee Att0meyWatts, Hoffmann, Fisher and Heinke [5 7] ABSTRACT Apparatus for loading and forming envelopes includes a supply structure for a web of plastic envelope blanks, web control means including a web feeding and locating mechanism and a web tensioning mechanism which cooperate to intermittently feed the web along a path of travel, a loading station at which the blank envelopes are loaded, and a forming station at which loaded blank envelopes are simultaneously sealed and cut to size. The web control means feeds a part of each blank envelope to a predetermined location on the path of travel. The feed of the web is then terminated with blank envelopes registered at the loading and forming stations. Loading and fonning apparatus operates in timed relation with the web control structure to perform the loading and forming operations when the web is stopped.
The web of blank envelopes is defined by a web of sheet plastic material which bears a printed image and folded on itself to provide coextending edges. The sides of the folded web are structurally connected in registration with the printed image. This connection between the sides of the web is engaged by a feed or tensioning mechanism during advancing of the web and also serves to locate material placed in the web relative to the printed image.
19 Claims, 11 Drawing Figures PAIENTEB FEB 15 m2 SHEU '4 OF 5 mvsmom HERSHEY LERNER BY PATENTEUFEB is me SHEET 5 OF 5 INVENTOR. HERSHEY LEE/V62 BY 9% METHOD AND APPARATUS FOR LOADING AND FORMING ENVELOPES AND BLANK ENVELOPE STRUCTURE USED THEREWITH CROSS-REFERENCED PATENTS US Pat. Re. No. 26,371, reissued Apr. 9, I968, entitled CONTINUOUS FORM ENVELOPES by Frank L. Schultz.
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to method and apparatus for loading and closing containers and more particularly relates to method and apparatus for producing formed, sealed plastic envelopelike containers by controlling the feed of an open sided web of blank envelopes along a path of travel through loading and closing stations.
There are numerous advantages in using plastic mailer envelopes rather than paper envelopes. These include low weight, and distinctive and attractive appearance.
Since the development of surface coatings which make plastic envelopes acceptable to the US. Post Office Department, tests have been conducted which demonstrate some of the advantages of plastic envelopes. For example, the tests show that direct mail advertisers achieve a significant increase in response. With these tests, some persons each received a mail advertisement in a paper envelope and others each received an identical advertisement in a plastic envelope. A significantly high percentage of those receiving the plastic envelopes responded to the advertisement.
While plastic envelopes are known to have these listed and other significant advantages, they have not achieved substantial commercial success. One reason they have not achieved success is that there has been no equipment which could load and close such envelopes at costs competitive with conventional envelopes.
2. The Prior Art Previously known mass mailing systems have utilized collating machines, for collating and loading material into conventionally formed individual mailer envelopes. Many different machines of this type have used a variety of envelope handling apparatuses so that individual envelopes with material inserted in them are sealed and appropriately handled preparatory to mailing. High speed collating machines have not had the capability ofloading and closing plastic envelopes.
In addition, plastic envelopes proposed by the prior art have not been entirely satisfactory for use in connection with conventional collating machines. Essentially, the prior art proposals have attempted to create a finished plastic envelope having an opening for loading after which the envelope is closed by heat sealing. An example of such an envelope and apparatus for forming the envelope is disclosed in the US. Pat. Re. No. 26,371 to Schultz.
The Schultz patent discloses envelopes in web form with the length of the envelopes extending transverse to the web travel so that loading the envelopes occurred in the direction of web travel. This orientation minimized the effects of web stretching on locating an envelope for loading since the load opening of these envelopes extended transverse to the expected stretching direction of the web.
The prior art has suggested loading containers in web form from one side of the path of travel of the web. These proposals have related to containers which in many cases are quite dissimilar to mailer envelopes, but enable quick and efficient loading.
Although mailer envelopes are referred to specifically, there are other packages which can be formed from plastic webs and which present, from a packaging standpoint, the same or similar problems as presented by mailer envelopes. Such plastic packages have the following characteristics: (1) They are formed with a material receiving volume having substantially the same size and shape as the material to be inserted in the volume; (2) They bear a printed image with which the material in the package must be registered; and (3) the plastic container must be accurately located for receipt of the material in the volume as well as for sealing and/or trimming the package to a desired size.
One problem which has faced the prior art is the difficulty in controlling a web of plastic container forming material during loading and forming operations. The principal reason for the difficulty in controlling such material is the dimensional instability of the plastic material forming the web. This instability results in an inability to construct containers with accurate dimensional tolerances. The problem is compounded when attempting to register inaccurately formed containers in a web at desired locations for loading and sealing.
In order to avoid the problem of locating the web, it has been proposed that the web be heat sealed adjacent an advancing member which will then engage the seal to advance the web to a desired location. This procedure requires that the sealed joint be cooled before advancing the web. Allowing cooling time obviously slows the entire process.
Furthermore, such proposals have not been faced with the additional problem of registering printed images on the web with loading and forming apparatus so that inserted material will be accurately registered with the printed image.
Another related problem has resided in maintaining web tension in a web of plastic material, without stretching it, while loading and forming. This problem is particularly acute when web movement must be intermittent and the web must be accurately located for loading and forming the container.
The noted problems are not unique to plastic envelopes. They can be encountered in packaging articles in plastic containers in which the article is substantially the same size as an article receiving pocket of a container and must be oriented in a particular way with respect to the container. In the case of a mailing envelope, the materials placed in the envelope must be oriented so that the addressee information registers with a printed image defining a window on the envelope. In the case of, for example, a hosiery package, a particular section of the hosiery must be aligned with a viewing window defined by a printed image. Furthermore, because of the size relationship between the container and material inserted in it, it is not generally feasible to insert web feeding mechanisms into the loaded container for feeding the web.
In summary, plastic envelopes formed in accordance with the prior art proposals have not been constructed to permit extremely high speed and efficient loading and forming of the envelopes. Similarly, apparatus for accomplishing high speed loading and forming of these envelopes has not been available and particularly apparatus of this type which is usable in connection with collating and loading machines which are in widespread use by mass mailers. Furthermore, prior art proposals for forming containers in a web and loading the containers from a side of the web have not dealt with problems arising in connection with loading containers similar to mailer envelopes at high rates.
SUMMARY OF THE INVENTION The present invention provides a new method and apparatus for loading and forming containers such as plastic mailer envelopes and is particularly suitable for use in connection with conventional collating and loading machines. The invention also provides a new blank printed plastic container construction in web form.
The new apparatus and web, when used in connection with each other, permit rapid intermittent feeding of a web of printed plastic container blanks which is accurately positionable for loading and forming operations. Although this apparatus is not limited to such use, the new apparatus is particularly adaptable for use in connection with an existing collating machine. Sold under the trademark Phillipsburg" by Bell and Howell.
The new web consists of a series of connected blank containers formed by folding a single printed web of material so that the edges coextend. The sides of the web are structurally preferably connected by a partial seal which extends from the fold toward the edges but terminates substantially short of the edges. Alternately, structural connection may, for example, consist of a staple or an adhesive connection. The edges are thus freely separable during loading without distorting the web. The partial seal provides a web part which can be engaged for advancing the web.
The sheet of plastic material is preferably printed prior to folding and the sides of the web are structurally connected at locations which are registered in a predetermined location relative to the printed images on the web.
A finished container formed from one of the described blanks may have ends defined by successive ones of the partial seals. Alternatively, such a container may have one of the partial seals disposed between the ends of the container. When the partial seal is between the container ends it provides partition which prevents matter contained in the pocket from sliding out of registry with the printed image. Thus, each pocketlike blank contains at least one partial seal. These partial seals, when engaged for web feeding, assure proper registration of the blanks for loading and forming when used in connection with the loading apparatus of this invention. The partial seals also locate inserted material relative to a printed image on the blank.
Apparatus for loading and sealing containers constructed in accordance with the present invention includes a suitable supply structure for a web of blanks; web controlling means for intermittently advancing the web along the path of travel; a loading station on the path of travel at which material is inserted into a blank aligned with that station; and a closing station on the path of travel at which a loaded blank is aligned for sealing, trimming scrap, and detaching the loaded and formed package from the web. A heated element is preferably used to close the package.
The web controlling structure includes a feeder mechanism and a web tensioning mechanism which cooperate to advance the web along the path of travel to a predetermined location at which spaced blanks are accurately registered with the loading and closing stations, respectively. Web motion is briefly terminated to allow for loading and closing, after which the web is again advanced.
In the preferred embodiment of the invention, the feeder mechanism includes a reciprocally movable member which engages the web during an advancing stroke and participates in moving the web along the path of travel to a predetermined location defined by the end of the stroke. The web engaging member engages the web upstream from the loading station. Prior to web engagement, this member is inserted in an empty pocket in the web. As the web advances, the member positions the connection between the web sides so that the container to be loaded is accurately positioned for loading.
The length of the strokes through which the web engaging member travels is greater than the length of a single blank of maximum dimension and less than twice the minimum blank length. The web engaging member is incapable of positively engaging the web during a return stroke and hence the web is not moved by the web engaging member during a return stroke.
Because of the relationship of the stroke length of the web engaging member to the length of blanks in the web being fed, the web engaging member successively engages the empty blanks one at a time. The member registers these blanks successively and one at a time at the predetermined position on the path of travel regardless of small differences in the length of the particular blanks being moved. Hence, at the termination of an advancing stroke of the web engaging member, an advanced blank in the web is accurately positioned.
The web tensioning mechanism comprises a belt drive having a belt disposed on the path of travel and in light frictional engagement with the web. The belt is effective to: (1) maintain the web in tension at the loading and forming stations; (2) transfer heat away from the forming station after each forming operation; and (3) eject formed packages from the apparatus.
The belt is intermittently driven in timed relation to advancing strokes of the web engaging member. The surface speed of the belt is greater than the advancing speed of the web. Since the belt surface engages the web with light frictional forces, slipping occurs between the web and the belt as the web advances. The frictional force acting between the belt and web is sufficient to maintain a controlled tension in the web between the belt and the web engaging member. In the preferred arrangement, this frictional force is not enough to move the web independently of the web engaging member.
The belt thus cooperates with the web engaging member to maintain the web in position at the loading and forming stations. After the package is closed and cut off, the belt accelerates the package away from the web and ejects the package from the apparatus.
Preferably the belt is driven from the loading machine in an intermittent fashion. The belt is stationary when loading and forming occurs. When such apparatus is utilized in connection with a Phillipsburg or similar collating machine, the belt is drivingly connected to an intermittently rotated shaft in the machine. This drive shaft operates in timed relation to the feed mechanism so that the belt is driven during an advancing stroke of the web engaging member. The drive shaft ceases to be driven when the web engaging member has reached the limit of its advancing stroke.
A brake structure is provided which cooperates between the drive for the web engaging member and the belt to positively brake the belt drive when the drive from the Phillipsburg machine terminates. The brake structure thus insures that the angular momentum of the belt drive does not cause the web to continue moving after it has been registered in the loading and sealing stations.
The loading station is in part defined by web engaging edge guides which separate the edges of the blank located at the loading station. These edges are freely separable. Material is inserted into the blank between the edge guides. The edge guides and loading elements are adjustably movable along the path of travel to provide for registration of different length blanks with the loading station. Separation of the blank edges at the loading station does not excessively distort the web and hence misalignment of the web with the forming station does not occur.
As is known, the Phillipsburg-type machines insert material into a container to a particular location. In a preferred em bodiment the web is fed to the loading station at an angle slightly greater than from the line of travel of material inserted into the blanks. The inserted material is thus pushed into the blank and against the remote side of the blank. The impingement of the loaded material with the remote side of the blank squares the web for movement to the closing or forming station while insuring that the material is fully inserted.
The closing station is defined in part by a heated element which is maintained at a temperature well above the melting temperature of the plastic. The element is supported for reciprocal movement toward and away from the path of travel in the feeding direction from the loading station. When the web has been advanced and stopped, a loaded blank is aligned with the heated element at the forming station. The heated element is moved to compress the web against the belt to seal the blank about the material. The element may also cut some of the web material from the package so that the edges of the formed package are substantially continuous and extend uniformly about it. The element also cuts the sealed package from the web while sealing. The heated element completes the sealing operation and is moved vertically away from the finished envelope blank prior to a succeeding feeding cycle of the Web.
In the preferred embodiment, the heated element is movably supported by apparatus which is operated in timed relation to the feeding mechanism so that the heated element is maintained spaced from the web at all times during feeding and contacts the web only when the web and belt are stopped.
The element engages the web and belt at different locations on the belt during successive forming operations. Thus, the belt carries away heat from the forming station and allows it to dissipate to prevent welding of the web at the forming station which might otherwise occur.
Blanks are supported on the belt of the tensioning mechanism during forming. After a forming operation is completed and the sealed package cut off from the web, the finished package lies on the belt detached from the web. As previously mentioned, the belt is operated at a surface speed which is greater than the feeding speed of the web. Thus, during the next feeding cycle of the web, the belt accelerates the sealed package away from the end of the web and off the path of travel to a suitable receptacle.
Accordingly, a principal object of the present invention is the provision of a new and improved method and apparatus for forming containers, such as mailer envelopes, from a novel web of plastic material which is simple, efiicient, and readily adaptable for use with existing equipment for loading material into containers.
Other objects and advantages of the present invention will become apparent from consideration of the following detailed description made with reference to the accompanying drawings which form a part of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically illustrates apparatus for forming a web of blank envelopes;
FIG. IA is a fragmentary view ofa portion ofa web of blank envelopes similar to the web shown in FIG. 1 and on a scale which is larger than a scale of FIG. 1;
FIG. 2 schematically illustrates apparatus for forming sealed mailer envelopes from the web of blank envelopes;
FIG. 3 illustrates a completed envelope formed by the apparatus illustrated in FIG. 2 and on a scale which is larger than the scale of FIG. 2;
FIGS. 4 and 5 are fragmentary views of a part of the apparatus of FIG. 2 shown in different operating conditions;
FIG. 6 is an elevational view of the apparatus shown in FIG. 2 which is illustrated on a larger scale than the scale of FIG. 2 and in greater detail, one end of the apparatus being broken away and illustrated out of position;
FIG. 7 is a plan view of the apparatus illustrated in FIG. 6 and with the end shown broken away and out of position;
FIG. 8 is an elevational view seen from the plane indicated by the line 88 of FIG. 7;
FIG. 9 is an enlarged fragmentary view of a part of the apparatus of FIG. 8 as seen from the plane indicated by the lines 9-9 of FIG. 8; and,
FIG. 10 is a fragmentary view of a part of the apparatus shown in FIG. 6, shown on a larger scale.
DESCRIPTION OF A PREFERRED EMBODIMENT Web Formation Apparatus FIGS. 1 and 2 illustrate stages in the manufacture and production of plastic mailer envelopes in accordance with the present invention.
FIG. 1 schematically illustrates blank envelope forming apparatus 10 through which a web W of transparent sheetlike polyethylene plastic is fed to produce a web of blank envelopes B. The apparatus 10 includes a printing couple 11, a web folding structure 12, and a structure 13 for structurally connecting sides of the web together.
The web W is fed into the printing couple 11 with the op- ,posite web edges 14a, 14b accurately aligned with an image producing surface on the printing couple so that printed images 15a, 15b are located medially of the edges 14a, 14b of the web on the otherwise transparent plastic material. The images 15a, 15b are suitable for defining the rear and forward sides of an envelope as is described in greater detail presently. A printed area 150 suitable for the permanent reception of ink in accordance with postal standards may be provided on the image 15b forming the forward side of the envelope. Similarly, an unprinted area 16 is provided adjacent the area 15c to define a window" through which the name and address of an addressee of an envelope can be seen after the envelope has been formed. Return addresses and Postal Permit Information is also printed at suitable locations on the envelope. The printing couple 11 is of any suitable type and therefore is not described in detail.
A conventional web folding structure 12 is schematically illustrated and is effective to fold the web W along its midline and thereby define a fold line 17 along the junctures of the images 15a, 15b. The edges 14a, 14b of the web are moved into coextending adjacent relationship with each other as the web passes through the folding structure. In certain circumstances, the folding structure 12 may be provided in advance of the printing couple 11 in the feeding direction of the web particularly in cases where only the forward side of the envelope is printed.
The folded web is then fed through the structure 13 so that sides of the web are structurally connected at locations registered with the printed images. The structure 13 includes a roll 19 drivingly connected to the printing couple which carries a heated rib 20 extending longitudinally of the roll on its periphery.
The driving connection between the printing press and the roll 19 assures that the roll 19 is driven in timed relation to the passage of the web past this roll. Since the roll is located adjacent the printing couple, stretching of the web, if any, is accurately predictable and the heated rib can be controlled to engage the web surface at desired locations.
The roll 19 thus rotates in timed relation of the passage of the web past the roll and the heated rib 20 is moved into pressure engagement with the web at predetermined spaced locations which are accurately registered with the printed images 15a, 15b. The rib 20 is preferably an electrical resistance heated element connected to a suitable electric power supply 21 through a slip ring assembly 22.
The illustrated structure 13 forms a partial seal 23 which structurally connects the sides of the web. It should be appreciated however, that any suitable means for connecting the sides of the web can be used, for example, staples or adhesive, so long as this connection is registered properly with the printed images.
A continuous web of blank envelopes B emerges from the sealer structure 13 with each blank envelope B configured as illustrated in FIG. 1A which shows the forward side of a web of the blank envelopes. Each blank B includes a complete image 15b having the ink receiving portion 15c and window 16 within the image 15b, and the partial seal 23 formed by the structure 13 as described to define a pocketlike material receiving portion in the blank which is registered with the printed image. The partial seal 23 extends from the fold line 17 defining the lower edge of the blank envelope and extend ing transversely of the web toward the edges 14a, 14b. The partial seal 23 extends slightly transversely of the web toward the edges 14a, 14b. The partial seal 23 extends slightly more than half way across the folded web so that the edges 14a, 14b can be moved apart freely without bulging the web or otherwise distorting the planar character of the web.
ENVELOPE LOADING AND FORMING APPARATUS FIG. 2 schematically illustrates envelope loading and forming apparatus 25 according to the present invention. The apparatus 25 includes a web supply structure 26, from which a web of blank envelopes B is directed along the path of travel P through the apparatus. The apparatus 25 further includes a loading station, generally indicated at 30, a forming station 31, and web control means 32 governing movement of the web along the path of travel P past the loading and forming stations.
The apparatus 25 produces individually formed mailer envelopes B (see FIG. 3) which have sealed ends 33, 34, a sealed upper or top side 35 and a lower side formed by the fold line 17. Scrap from the top of the envelopes E, i.e., the material adjacent the edges 14a, 14b, is trimmed off during sealing of the top side 35. The matter which has been loaded into the blank at the loading station is oriented with respect to the window 16 so that the name and address of the addressee is clearly visible through the window.
Referring to FIG. 6, the apparatus 25 includes a horizontal support plate 40 and a feed table 41 consisting of a horizontally extending platelike member supported above the plate 40 and along which the web is fed. The feed table 41 is rigidly connected to the support plate 40 by an end plate 42 adjacent the web supply structure. The feed table 41 is also rigidly attached to the plate 40 remote from the end plate 42 by suitable rigid spacers which are not illustrated.
The Web Supply Structure The web supply structure 26 includes a web supporting shaft 43 rotatably supported in a bearing plate 44. The plate 44 is rigidly connected to the end plate 42. The shaft 43 extends horizontally from the bearing plate 44 for reception of a spool (broken lines FIGS. 4) which supports a rolled web of blank envelopes.
The web is reaved around tensioning rolls 45, 46 and a dancer roll 47 intermediate the tensioning rolls. The rolls 45, 46 are connected to the plate 44 and extend horizontally to guide the web as it proceeds from the spool onto the feed table 41. These rolls can be adjustably positioned along their axes to control the direction of feed of the web along the feed table.
The dancer roll 47 is rotatably secured to an end 48a of a support member 48. The opposite end 48b of the member 48 is pivotally connected to the plate 44. The member 48 is constructed of heavy rigid material, the weight of which provides a substantially constant tension in the web as the web is fed onto the table. A looplike central portion 48c of the member 48 is provided with a pad of friction material to brake the spool when the dancer roll 47 is in its lower most position.
The Web Control Means The web control means 32 includes a feeder mechanism 50 (see FIGS. 6 and 7) for drawing the web from the web supply structure. The feeder mechanism is located upstream from the loading and forming stations and engages partial seals bounding empty blanks to draw the web from the web supply structure. This mechanism accurately located each engaged partial seal to assure proper registration of down stream blanks with the loading and forming stations.
The feeder mechanism includes a web engaging member 51 (FIGS. 4 and supported for reciprocating motion along the feed table 41. A drive mechanism, generally shown at 52, drives the web engaging member. The drive mechanism 52 reciprocally moves the web engaging member along the feed table through a stroke S (FIG. 2).
The web engaging member 51 includes a web engaging finger 53 which normally extends over the feed table 41 generally transverse to the path travel P of the web. The finger 53 is connected to a finger supporting member 54 by a hinge 55. When the finger 53 is in its normal position, i.e., extending transversely of the path of travel P, the finger presents a force transmitting surface 56 engageable with a partial seal 23 of an empty blank envelope B in the web. The finger 53 and supporting member 54 are provided with abutment surfaces 57, 60, respectively, which are engaged when the finger is in its normal position. Thus the force transmitting surface 56 is rigidly maintained in position during feeding of the web and is incapable of rotating about the hinge 55 as a result of resistance of the web to feeding motion.
The finger 53 is resiliently deflectible away from its normal position in a clockwise direction as seen in FIGS. 4 and 5. Hence, the finger is incapable of transmitting motion to the web during the return stroke of the finger. As seen in FIGS. 4 and 6, a biasing spring 61 is connected between the finger and finger supporting member for maintaining the finger in its normal position. In the illustrated embodiment, the biasing spring 61 is a helical tension spring having a spring rate which is sufficient to maintain the abutment surfaces 57, 60 in light pressure engagement when the finger is disengaged from the web.
The length of the stroke S through which the finger 53 travels is substantially longer than the length L of an individual blank in the web. Therefore, during a feeding stroke the finger 53 travels part way through the stroke before engaging the web. When the finger engages the web, the engaged blank B in the web is fed along the feed table 41 to a predetermined location regardless of the length L of the particular blanks being fed.
On a return stroke, the finger 53 impinges upon a partial seal 23 (FIG. 5) of the following blank B. The spring rate of the spring 61 is such that the finger 53 is rotated about the hinge 55 on engagement with the partial seal 23 in the following blank and hence the web of blanks is incapable of being moved by the finger 53 during the return stroke.
In order to accommodate movement of the finger 53 over the partial seal 23', a smoothly curved cam surface 62 is formed at the projecting end of the finger. The cam surface facilitates sliding of the end of the finger over the partial seal without tearing the plastic material.
When the finger 53 moves out of engagement with the following partial seal 23', the spring 61 returns the finger to its normal position at which the finger is positioned for rigid feed ing engagement with the partial seal 23' during a subsequent feeding stroke.
Drive Mechanism for the Web Engaging Member The drive mechanism 52 continuously drives the web engaging member back and forth along the table 41 and because of the operation of the finger 53, as described, the feed of the web is intermittent. Referring to FIG. 6, the drive mechanism 52 includes an electrically operated motor M (shown schematically) having an output shaft 63 connected to a speed reducing gear box 64. An output shaft 640 of the gear box carries a crank member 65 which is drivingly connected to a connecting rod 66 by a bearing assembly 67.
The connecting rod 66 has a rack 70 attached to its end remote from the bearing 67. The rack is meshed with a pinion gear 71 and supported in meshing engagement with the pinion gear by a cradlelike bearing support 72 which is slidably supported upon the shaft 71a of the pinion gear 71.
The rack 70 reciprocates back and forth in response to rotation of the crank arm 65 and it is apparent from FIG. 6 that the angular relationship between the rack and horizontal changes continuously throughout a rotational cycle of the crank arm. The cradlelike support 72 is freely movable about the pinion shaft 71a and hence supports the rack 70 in meshing engagement with the pinion 71 regardless of the angularity of the rack with respect to horizontal.
The crank arm rotation is in a clockwise direction as viewed in FIG. 6 and it should be appreciated that during I of crank arm rotation immediately following the illustrated position of the arm the rack moves toward the right resulting in counterclockwise rotation of the pinion gear 71. During the subsequent rotation of the crank arm the rack is drawn toward the left causing rotation of the pinion gear in a clockwise direction.
The motion imparted to the pinion gear 71 is transmitted to the web engaging member 51 by way of a chain drive generally indicated at 73. The chain drive 73 includes an endless chain 74 reaved about a drive sprocket 75 supported on the pinion gear shaft 710. The shaft 71a is preferably supported by pillow blocks 71b screwed to the plate 40 intermediate the pinion gear 71 and the drive sprocket 75.
The chain 74 is additionally reaved about a tension adjusting sprocket 76 and guide sprockets 77, 78. As seen in FIG 6 the tension adjusting sprocket is associated with an adjusting mechanism 79 which permits movement of the tension adjust sprocket to a desired location after which it is clamped in place to appropriately tension the chain 74. The sprockets 77 and 78 are supported to define a horizontal upper reach 74a of the chain which extends parallel to the feed table 41.
The web engaging member 51 is supported on a movable carrier 80 which is attached to one or more links in the chain 74 and which is moved by the chain along a horizontal guide structure 81 supported immediately beneath the feed table 41. In the illustrated embodiment the guide structure 81 includes a cylindrical member 82 which extends through a cylindrical bore in the carrier 80.
The upper chain reach 740 is reciprocated back and forth between the guide sprockets 77, 78 due to the motion of the pinion gear 71 and drive sprocket 75. The carrier 80 is likewise reciprocated back and forth along the guide member 82 thus cyclically moving the finger 53 through its stroke.
The feeder mechanism 50 is constructed to advance each blank in the web of blank envelopes to a predetermined location on the path of travel P. More specifically the partial seal 23 of each blank is moved to a location, indicated by the line X, adjacent the end of the feed table 41 remote from the web supply structure. This location is closely adjacent the loading station 30 and it is apparent that the partial seal 23 of each blank will be on the line X regardless of the size or shape of the particular blanks in the web being fed.
Due to the dimensional instability of the polyethylene plastic film forming the web, it has, in the past, been difficult to feed such a web to a location at which a receptacle formed by the web, such as an envelope, is accurately registered with a loading station. This problem has further been aggravated by the fact that various sized receptacles in web form must be capable of being handled by loading and forming equipment.
Apparatus constructed in accordance with the present invention overcomes the aforementioned problems by providing a feed mechanism which moves individual ones of the receptacles to a particular location along the path of travel regardless of the size of the blanks. Since the predetermined position to which the web is fed is closely adjacent loading and forming stations, the receptacles are accurately registered with the loading and forming stations. This is true even though the web material is dimensionally unstable and may therefore not be extremely accurately formed.
WEB TENSIONING MECHANISM While it is apparent that the feeder mechanism described above operates to accurately position a part of a blank envelope at a predetermined position along the path of travel regardless of the size of the blank, it should also be appreciated that accurate registry of blanks with loading and forming stations spaced in the feeding direction from the predetermined location will not be assured unless the web is maintained under a slight tension in the feeding direction from the feeder mechanism.
Accordingly, the web control means 32 includes a tensioning mechanism 85 for tensioning the web along locations spaced in the feeding direction from the feeding mechanism. The preferred tensioning mechanism 85 is a belt drive which frictionally engages the web along that portion of the path of travel P extending adjacent the loading and forming stations. The belt drive 85 maintains tension during feeding to insure that the web is flat and accurately aligned with the loading and forming stations when feeding terminates.
The belt drive 85 includes a belt 86 trained around pulleys 90-92. The pulleys are rotatably supported in side frames 93, 94 which extend upwardly from opposite sides of the support plate 40 beyond the feed table 41 in the feeding direction. The pulleys 90, 91 are spaced apart to define a horizontal reach 86a of the belt 86 extending in the plane of the feed table 41 and beyond the loading and forming stations. In the preferred embodiment, the horizontal reach 860 is supported by a plate 95 connected between the side frames 93, 94.
The belt 86 is constructed of a rubber impregnated cotton duck material. The rubber surface, which may be silicon rubber, frictionally engages the web with a sufficiently large frictional force to insure maintenance of tension in the web. The belt is driven at a surface speed which is greater than the advancing speed of the web. Hence the belt and web continuously slip during feeding motion of the web. The frictional force between the web and belt is not so great that the web is advanced away from the finger 53 of the feeder mechanism 50 during feeding, but is sufficiently large to insure that the web remains flat and under slight tension as the finger feeds and locates the web. Pressure roll constructions 96, 97 are provided to insure an adequate friction force.
The belt 86 is intermittently driven in timed relation to feeding of the web and loading of blank envelopes in a manner described in greater detail presently.
The Belt Tensioning Structure The belt drive includes pulley supporting structure for maintaining a suitable tension in the belt and which also functions to assure quick and easy replacement of the belt should replacement become necessary. The pulley supporting structure, generally indicated at 100 in FIGS. 6 and 7, includes slides 101, 102 which support opposite ends of the pulley 91. As best seen in FIG. 6 the pulley 91 includes shaft portions 91a disposed in a slot 103 in each slide and held in position in the slot by a pivot pin 104.
The slides are disposed in slots 105 in the side frames 93, 94. The slides have grooves in their upper and lower sides respectively, which receive tongues formed at the boundaries of the slots 105. These tongue and groove connections, provide for horizontal sliding movement of the slides relative to the side frames.
The slides 101, 102 are urged toward the left as viewed in FIG. 6 by a spring tensioning assembly 109 including a force applying bar 110 which extends between the slides 101, 102.
The ends of the slides opposite the pulley supporting ends include an opening 112 through which dowel pins 113 extend. The bar 110 has forked ends in which the pins 113 are slidably received.
The bar 110 is fixed to a vertical shaft medially of its ends. The shaft 120 is rotatably disposed in a support member 121. The member 121 includes a pair of cylindrical guides 125, 126 which extend through bushings formed in a support frame 127 connected between the side frames 93, 94. Compression springs 130, 131 surround the guides and urge the bar 110 and slide members 101, 102 to the left as viewed in FIG. 6 thus maintaining the belt suitably tensioned about the pulleys 90-92.
The support member 121 is manually moved to compress the springs 130, 131 thereby removing the tension from the belt to allow removal of the belt. When removal of the belt is desired, a drawbar 133 connected to the support member 121 is pulled to compress the springs 130, 131 drawing the slides 101, 102 and the pulley 91 to the right as seen in FIG. 6. This results in the belt being loosened.
The drawbar is 133 connected to a lever 137 by a link 140. The lever 137 is rotatably movable in a horizontal plane about a pivot construction 141. When the lever is moved counterclockwise as seen in FIG. 7 the link and draw bar are effective to release the tension in the belt as described.
In the preferred construction, the lever 137 extends through an L-shaped slot 142 in the side frame 94. The horizontal leg of the slot 142 is sufficiently long that the lever 137 will not engage its left end (FIG. 6) when the belt 86 stretches during normal use. Hence the springs 130, 131 govern the belt tension at all times during normal operation.
When the lever 137 is moved to the right end of the slot (FIG. 6) the pulley 91 is retracted to release the belt tension. The lever 137 includes a hinge 143 permitting movement of a handle portion of the lever downwardly. When the lever is at its limit of travel in the slot 142 the handle portion of the lever is moved downwardly about the hinge 143 and into a locking recess formed by a short leg of the L. The locking recess includes a lip 145 for maintaining the lever in the recess when the pulley 91 is retracted against the spring force during belt removal and replacement. As shown in FIG. 6 the side frame 94 is generally triangular and does not extend beyond the peripheries of the pulleys 90-92. This permits easy removal of the belt.
The belt 86 is guided over the pulleys 90-92 to insure that the web of envelopes remains disposed along the path of travel for proper registry with the loading and forming stations. In the illustrated apparatus the pulley 91 can be skewed slightly in a horizontal plane so that the belt tracks on the pulleys as desired.
The pulley 91 is skewed by rotating the bar 110 slightly about the axis of the shaft 120 and thereby shifting the slides 101, 102 in opposite directions relative to the support plates. For this purpose the shaft 120 is fixed to the bar 110 and carries a gear 146. The gear 146 meshes with a worm. 147 on a shaft 150 extending through the frame 94. A knob 151 on the end of the shaft 150 permits manual rotation of the shaft to adjust the pulley through the gears 146, 147.
The Loading Station As has been pointed out previously, the apparatus 25 is usable in connection with a Phillipsburg-type collating and stuffing machine and is described in reference to such a machine so far as operation of the Phillipsburg machine effects operation of the apparatus 25. Phillipsburg machines are well known and accordingly this machine is neither shown in detail nor described except to state that the Phillipsburg machine collates material for stuffing into the envelope blanks at the loading station. When collating is accomplished, the material is inserted into each blank envelope when the blank is stationary arid registered at the loading station.
As seen in FIG. 9 the side frame 93 mounts a guide structure 154 including a pair of sheet metal guides 155, 156 which are positioned over the belt 86 and extend between the edges 14a, 14b of the web. The upper guide 155 has downwardly curbed ends 157, 158 and a smoothly curved medial portion 160 extending between the ends. The guide member 156 is generally planar and extends parallel to the upper reach 86a of the belt in spaced relationship with the medial portion 160 of the upper guidev As the web feeds along the path of travel P the edges 14a, 14b of the web are separated by the guides 155, 156 and when an individual blank is registered at the loading station, the collated material is inserted into the blank between the guides. Because of the spaced relationship between the partial seals 23 and the web edges 14a, 14b separation of the edges 14a, 14b by the guides does not bulge or otherwise misalign the web which might otherwise result in misalignment of a preceding blank with the forming station. The thickness of the plastic web material is shown exaggerated in FIG. 9 for the purpose of illustration.
In the preferred construction, the rolls 45, 46 of the web supply structure are adjusted so that the web is fed at an angle slightly larger than 90 to the direction of insertion of material into the blanks at the loading station. Hence, the material inserted in the blanks at the loading station impinges on the fold line 17 to assure that the material is bottomed out in blanks. When the insert material is urged into the blanks the web is moved back to the path of travel by the material being inserted.
As has been previously noted, the belt drive 85 is intermittently driven and is driven during the time that the feeder mechanism is advancing the web. In the illustrated and preferred embodiment the belt drive 85 is driven from the Phillipsburg machine through a shaft 165 (FIG. 7) which is driven in timed relationship to operation of the Phillipsburg machine. Essentially, the shaft 165 is driven during collating and ceases to be driven prior to loading.
The shaft 165 drives the belt pulley 90 through a gear train including a gear 166 carried on the shaft 165, an adjustable idler gear 167 and a driven gear 168 attached to the pulley 90. The idler gear 167 is connected to a support member 170 (see FIG. 6) which is movably connected to the side frame 93 by a clamp 171. The clamp 171 is loosened to enable the member 170 to move relative to the side frame 93. This enables the idler gear to be moved and thus adjust the backlash between the idler gear and the gears 166, 168. The described adjustment of the idler gear aids in installation of the apparatus 25 to an existing Phillipsburg machine as the centers of the shaft 165 and the gear 168 need not be precisely located relative to each other on assembly. The ratios of the gears 166, 168 are such that the belt 86 is driven at a surface speed which is approximately 1% times the advancing speed of the web.
Where a collating and loading machine which does not have an equivalent of the shaft 165 is associated with the apparatus 25 the belt drive may be modified to be driven in timed relation to the drive mechanism 52.
Feeder Operated Brake for the Belt Drive Although the belt drive 85 is not positively driven from the shaft after feeding is terminated, the angular momentum of the parts of the drive is sometimes sufficiently great to cause the belt to continue movement even after the drive is terminated. Continued motion of the belt under such circumstances can cause misalignment of the blank envelopes with the loading and forming stations and accordingly a brake 175 (see FIG. 10) is provided between the feed mechanism and the belt drive. The brake positively stops belt movement at the termination of each feeding cycle of the web. The brake 175 includes a stop member 176 fixed to the end of the shaft 165 which projects through the side frame 93. The stop member 176 includes a radially extending subtment surface 177.
A brake assembly 178 is cyclically moved toward and away from engagement with the abutment surface 177 in timed relation to rotation of the crank arm 65 to engage and positively stop rotation of the shaft 165 at the end of each feeding stroke. As seen in FIG. 10, the brake assembly 178 includes a tubular body 180 in which a pin 181 is slidably disposed. The pin has an enlarged head 181a engageable with the surface 177 on the stop member and a compression spring 182 is disposed between the body and the enlarged head. The pin is suitably restrained against withdrawal from the body and the compression spring dampens the impact forces between the brake assembly and the stop member 176 when the pin and stop member are engaged.
The brake assembly 178 is carried on a rock shaft 185 which is rotatably supported in the side frame 93. The rock shaft is connected to an L-shaped follower arm 186 (see FIG. 7) which carries a roller follower 187. The roller follower 187 runs in engagement with a cam 190 fixed to the output shaft of the gear box 64.
A spring 191 is connected between the arm 186 and the plate 40 to maintain the follower on the cam periphery.
The cam 190 has a generally circular dwell portion on which the follower 187 rides when the web engaging member is away from the end of the feeding stroke. When the web engaging member is near the end of its feeding stroke, the cam follower 187 rides on to a reduced radius portion of the cam 190 causing the rock shaft to move the brake member to position for engagement with the abutment surface 177 on the stop member. When the stop member engages the pin 181, rotation of the drive shaft 165 is positively terminated, thus stopping movement of the belt 86.
To further insure prompt stopping of the web at the end of the feeding stroke, a pair of suckers 195 are supported by the feed table at the center of the path of travel. The suckers are conventional and communicate with a source of vacuum pressure through a suitable conduit and valve (not shown). As is conventional, the vacuum valve can be operated in timed relation to the drive for the web engaging member.
The Forming Station The forming station 31 is defined by an envelope forming assembly 220 which is effective to seal the blank envelopes closed, trim scrap from the envelopes, and cut off the thus formed envelopes. An actuating mechanism 221 operates the forming assembly (FIG. 8).
The forming assembly 220 includes a heated sealing element 222, a sealing element housing 223, and a housing support assembly 224 (FIG. 8). The element 222 is an electrical resistance heated element and is movable into and away from engagement with the web. The element is maintained substantially above the melting temperature of the plastic web. The element compresses the web against the belt during cutting and sealing of the web. As a consequence, the belt is heated by the element due to conduction through the web. Since the belt is driven between forming an assembly no one location on the belt is heated by the element during successive cycles. This prevents any location on the belt from being heated sufficiently to cause sticking of the web to its support at the forming station since the belt carries heat away from the forming station after each forming operation.
The element 222 includes a transverse leg 225 which extends across the web and beyond its opposite sides. This insures that envelopes formed at the form station are severed from the web, as is described presently in more detail. The element also includes a parallel leg 226 which extends along the path of travel and intersects the transverse leg 225 near one end.
The legs 225, 226 are provided with a downwardly extending knife edge 227 so that when the element 222 is moved into engagement with the web, the heated knife edge both cuts and seals the portions of the web it contacts.
The parallel leg 226 is longer than the maximum length envelope blank utilized in the apparatus. Thus, when the heated element 222 is moved into engagement with the web the parallel and transverse legs produce a formed, sealed envelope which is separated from the web. A rectangular piece of scrap envelope material is also cut off from the web and the formed envelope. The formed envelope remains on the belt 86 while the scrap material may be suitably drawn away from the apparatus by a vacuum system which has not been illustrated.
The housing 223 includes a body 230 and depending legs 231 which are suitably connected to the element 222 for rigidly connecting the element to the body 230.
The support assembly 224 includes support plates 233 (FIG. 7) which are attached to the side frame 93 at spaced locations. A pair of horizontally extending cylindrical guides 234 extend between the support plates. A support body 235 is slidably disposed on the guides 234 and rigidly supports a pair of parallel vertically extending guide rods 236. The guide rods 236 are connected together at their upper ends by a connecting frame 237.
An elevator assembly 240 is slidably disposed on the guide rods 236 and supports the element 222 and housing 223 for vertical movement toward and away from the path of travel P. The elevator assembly 240 includes a body 241 through which the guide rods 236 extend and the housing support plate 242 connected to the body. Housing support plate 242 mounts four pins 243 which extend through the support plate 242 and are attached at their ends to the housing body 230. The pins 243 have threaded upper ends which receive stop nut structures 244 which are adjustable to shift the pins 243 vertically relative to the plate 242 hence control the position of the housing body 230 relative to the support plate. Each pin includes a compression spring which is disposed between the support plate 242 and the housing body 230. The springs cushion any undue impact forces between the heated element 222 and the web belt as the heated element is moved downwardly into engagement with the web as is described presently.
The support plate 242 is adjustable transversely of the path of travel P relative to the body 241 to facilitate the production of envelopes having various dimensions between their upper" and lower" sides. The transverse adjusting structure (see FIG. 7) includes a guide slot 246 formed in the body 241 and a lug 247 on the support plate 242 which is disposed in the slot 246. An adjusting screw 250 is threaded into the body 241 and extends through the lug 247. The lug and adjusting screw are fixed against relative axial movement while being free for relative rotation and hence as the adjusting screw 250 is turned the lug and support plate 242 move transversely along the path of travel relative to the body 241.
The support body 235, along with the guide rods 236, eleva tor assembly 240 and associated structure are movable longitudinally along the path of travel in order to adjust the position ofthe element 222 to accommodate various lengths ofenvelopes to be produced. In order to accommodate longitudinal adjustment, a screw 253 is rotatably supported in the support plates 233 by bearings 254. The support body 235 includes a threaded opening 255 which receives the screw 253 so that as the screw is rotated the body 235 moves parallel to the path of travel P along the screw.
The screw 253 is manually rotatable when adjustment of the position of the element 222 is desired. In the preferred embodiment a helical gear 256 is fixed to the screw beyond the end of the threads of the screw. The gear 256 is driven from a helical gear 257 which is supported on a drive shaft 260 rotatably supported in the side frames 93, 94. A hand wheel 261 is fixed to the end of the drive shaft 260 which projects from the side frame 94.
The elevator assembly 240 is vertically movable along the guide rods 236 in timed relation to operation of the feeder mechanism by the actuating mechanism 221. The actuating mechanism 221 includes a cam drive 265 having a driving cam 266 fixed to a shaft 267. The shaft 267 is mounted on bearings 268 which are connected to the plate 40. The shaft 267 is driven from the motor M by a chain 270 which is trained around sprockets 271, 272 fixed to the motor shaft 263 and camshaft 267, respectively.
Motion is transmitted to the elevator assembly 240 from the cam 266 by a follower assembly 275. The assembly 275 includes a cam follower 276 of the roller type which rides on the periphery of the cam 266 and a follower support 277 which extends between the roller follower 276 and a rock shaft 280 which is rotatably supported in the support plates 233. Links 281 are fixed to the rock shaft 280 at spaced locations and the outwardly extending ends of the links are articulated by a support bar 282 rotatably supported by the links.
A linkage 283 is connected between the support bar 282 and the elevators 240 to transmit motion from the cam follower assembly 275 to the elevator assembly. The linkage 283 includes a link member 284 which is rotatably and slidably supported upon the support bar 282 and a connecting rod 285. The connecting rod has a threaded end 286 screwed into the link member 284 and a bearing 287 at its opposite end connected to the body 241 of the elevator assembly.
As is best seen in FIG. 8 the cam 265 includes a cylindrical dwell surface portion 266a and a fall and rise surface portion 266b. When the web engaging member of the feeder mechanism is away from the end of its feeding stroke the follower 276 is engaged with the cam surface 266a and the sealing element 222 is elevated from the web. When the web engaging member is in the vicinity of the end of its feeding stroke the follower rides on the cam surface 266b resulting in rotation of the rock shaft 280 in a counterclockwise direction, as seen in FIG. 8, causing the links 281 and support bar 282 to move downwardly about the rock shaft. This pulls the linkage 283 and connected elevator assembly 240 downwardly to engage the sealing element with the web.
When the web engaging member nears the beginning of its feeding stroke the follower 276 is engaged with the rise portion on the cam surface 266b causing the rock shaft 280 to rotate in a clockwise direction, as seen in FIG. 8, which consequently forces a linkage 283 upwardly to move the elevator assembly 240 upwardly thereby disengaging the sealing element 222 from the web.
in the illustrated and preferred embodiment of the inven tion an air cylinder 295 maintains the follower 276 in engagement with the cam 266. The air cylinder is pivotally connected between the link member 284 and the connecting frame 287 at the upper ends of the guide rods 236. The cylinder 295 includes a cylinder forming member 296 housing a piston and a piston rod assembly 297. The piston and piston rod assembly 297 are continually urged axially away from the cylinder member and hence exert a downward force on the link member 284 at all times. The force exerted on the link member 284 by the air cylinder 295 maintains the follower 276 in positive engagement with the cam 266 at all times during operation of the apparatus.
It can now be seen that a new and improved method and apparatus for the production of mailer envelopes have been provided and that the objects theretofore enumerated and others have been accomplished. It should further be understood that the description and drawings are of a preferred embodiment of the invention and that numerous changes and modifications can be made without departing from the principles of the invention.
1. ln an apparatus for inserting material into spaced pockets in a web, the combination of:
a. web supply structure;
b. web controlling means including cooperating mechanisms for feeding, tensioning and indexing a web, said mechanisms cooperating to intermittently advance said web along a path of travel;
c. one of said mechanisms including a web engaging member extending into and engaging a part of a first container pocket to locate said part at a predetermined location on said path when said web is indexed;
d. structure defining a loading station spaced from said predetermined location in the feeding direction along said path of travel and at which matter is inserted into a second pocket; and,
e. the other of said mechanisms effective to maintain said web in tension on said path of travel during indexing to register said second pocket with said loading station.
2. In an apparatus as claimed in claim 1 wherein said drive mechanism for said web engaging member cyclically moves said web engaging member reciprocally along said path of travel between said predetermined location and a second location, said web engaging member engaging said part of a container pocket during movement from said second location to said predetermined location and said drive mechanism moving said web engaging member away from engagement with said part when said part is at said predetermined location.
3. Apparatus as claimed in claim 2 wherein said predetermined location and said second location are spaced apart a distance which is larger than the length of indexing movement of said web during a cycle of movement of said web engaging member.
4. Apparatus as claimed in claim 2 wherein said drive mechanism further includes support structure for said web engaging member which positions said web engaging member to extending generally transversely of said path of travel for nonyieldably engaging a web pocket part during movement from said second location to said predetermined location.
5. Apparatus as claimed in claim 4 wherein said support structure for said web engaging member enables said member to resiliently deflect away from said position transverse to said path of travel in response to engagement with a part of a container pocket in the vicinity of said second location, during movement from said predetermined location to said second location.
6. Apparatus as claimed in claim 1 wherein said web engaging member is disposed between said web supply structure and said web tensioning mechanism.
7. Apparatus as defined in claim 1 wherein said web tensioning mechanism includes a tensioning member having a surface engaging said web for applying a tensioning force to said web, said surface moving in the feeding direction as said web is indexed to maintain the web in tension during indexing.
8. Apparatus as claimed in claim 7 wherein said tensioning member includes a belt having a reach supporting said web, and drive means for said belt effective to move said reach at a surface speed greater than the speed of said belt during indexing whereby to establish a frictional tensioning force between said belt and said web.
9. Apparatus as claimed in claim 8 wherein said belt is intermittently driven in timed relation to indexing of said web, and means for braking motion of said belt when said web has been indexed.
l0. Apparatus as claimed in claim 7 wherein said surface frictionally engages said web and further including drive means for moving said surface at a greater speed than the indexing speed of said web.
11. Apparatus as claimed in claim 10 and further including a forming station along said path of travel and a heated container sealing device at said forming station, said sealing device engageable with a portion of said web supported by said surface at said forming station when said web has been indexed, said such supporting surface transferring heat from said forming station as said web is indexed during a succeeding indexing movement of said web.
12. Apparatus as claimed in claim 11 wherein said sealing device cuts off sealed containers from said web and said support surface moves to accelerate cut off containers away from the web and eject said containers from said forming station.
13. A method of forming packages from a web of material comprising:
a. folding the web to define coextending sides and parallel edges;
b. structurally connecting said sides at spaced locations on said web;
c. registering each structural connection with the web a predetermined distance from at least the next adjacent structural connection;
d. adjacent structural connections defining limits of a fillable space in the web therebetween;
e. feeding said web along a path of travel extending past a loading station;
f. engaging successive structural connections between said coextending sides while feeding said web;
g. locating each successive structural connection at a predetermined location on said path of travel;
h. registering successive fillable spaces at said loading station spaced in the feeding direction from the engaged structural connection while locating said connection;
i. inserting material in fillable spaces registered at said loading station; and,
j. tensioning said web while feeding said web to said loading station.
14. A method as claimed in claim 13 wherein said web is composed of plastic film.
15. A method as claimed in claim 13 and further including a closing station on said path of travel, registering loaded fillable spaced at said closing station while locating said engaged structural connection, and closing the web about said material to define a closed package.
16. A method as claimed in claim 15 wherein tensioning said web includes tensioning said web while feeding said web to said closing station.
17. A method as claimed in claim 15 and further including separating said closed package from said web while closing said web about said material.
18. A method as claimed in claim 17 and further including accelerating a separated package away from said web while tensioning said web.
19. A method of forming packages comprising:
a. printing a succession of images on a web of plastic materib. folding the web to define a fold line and coextending web sides having parallel edges;
c. structurally connecting said coextending sides at locations registered with each printed image to define a series of container blanks in the web;
d. feeding said web of container blanks along a path of travel;
e. engaging successive connections between said coextending sides and sequentially locating said connections at a predetermined location on said path;
f. tensioning said web in the feeding direction from said location along said path;
g. stopping the feed of said web of containers when a struc tural connection between said sides is fed to said location;
h. loading material into a blank container at a loading sta tion spaced from said location in the feeding direction while the feed of said web is stopped; and,
i. forming packages from loaded container blanks.