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Publication numberUS3361612 A
Publication typeGrant
Publication dateJan 2, 1968
Filing dateNov 24, 1964
Priority dateFeb 12, 1962
Publication numberUS 3361612 A, US 3361612A, US-A-3361612, US3361612 A, US3361612A
InventorsFrancis W Rowbottam
Original AssigneeFrancis W. Rowbottam
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for screen assembly
US 3361612 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

Jan. 2, 1968 F. w. ROWBOTTAM 3,361,612

APPARATUS FOR SCREEN ASSEMBLY 2 Sheets-Sheet 1 Original Filed Feb. 12 1962 INVENTOR 541w: 1/ Fan/earn! 7 fideb,

A T 7051/6 ys Jan. 2, 1968 F. w. ROWBOTTAM 3,361,612

APPARATUS FOR SCREEN ASSEMBLY 2 Sheets-Sheet 2 Original Filed Feb. 12 1962 Rm O r E E w mm mm 8 p T M F J M Patented Jan. 2, 19%? 3,361,612 APIARATUS FDR SCREEN ASSEMBLY Francis W. Rowbottani, Gardena, tialif. (15134 S. Vermont, Los Angeies, Calif. 90044) Original application Feb. 12, 1962, Ser. No. 172,499, new Patent No. 3,214,314, dated Oct. 26, 1965. Divided and this application Nov. 24, 1964, Ser. No. 413,571

7 Claims. (Cl. 156-495) ABSTRACT OF THE DISCLOSURE Apparatus for installing screening from a roll onto framing having marginal edges provided with a fusible material. The framing is moved across a conveyor belt with the screening from the roll being positioned above the framing. A pair of parallel rollers are positioned above the conveyor belt and normal thereto to cooperate with the conveyor belt in driving the framing and the screening in the direction of movement of the belt. One of the upper rollers rotates faster than the conveyor belt to thereby tension the screening over the framing. One of the upper rollers is heated so as to fuse the fusible material to the screening and hence to the framing as the screening is maintained tensioned.

This is a division of patent application Ser. No. 172,- 499, filed Feb. 12, 1962 now Patent No. 3,214,314.

This invention relates to method and apparatus for screen assembly and is particularly concerned with automated installation of screening upon a frame, it being a general object of this invention to automatically assemble screening upon frames that vary in size and in proportion.

Screening is ordinarily installed by hand upon frames that are designed to maintain said screening in a taut planar condition. In order to properly apply screening to frames a technique must be developed whereby appropriate tautness is achieved, but without distorting the frame. The problem arises in the frailty of the frames which are of light construction and which have a rabbet groove for the reception of a retaining strip or filler that wedges the marginal portion of the screening in said rabbet groove. The filler strip is usually applied with an in strurnent adapted to apply pressure with experienced manipulation, with the screening beneath the filler strip so as to be pressed into the rabbet groove. In any case, the careful manual application of the filler strip to retain the screen in the rabbet grooves is time-consuming, and the output of a skilled Workman is rather limited, the installation of said screening being slow and tedious.

An object of this invention is to receive random sized frames and to install screening thereon without resort to manual labor.

Another object of this invention is to provide an apparatus for the purpose set forth above and which operates continuously and without interruption. That is, the method and apparatus herein disclosed does not intermittently start and stop, and on the contrary it operates at a uniform and continuous rate of speed.

it is an object of this invention to provide a method of assemblin screening upon a frame whereby tedious manual operations are eliminated and whereby said screening is anchored by means of a single easily performed step, a step that is readily performed by a machine or apparatus, when circumstances require.

It is still another object of this invention to provide a unique method whereby screening is permanently attached to a supporting frame, without the usual tedious timeconsuming manipulations that are ordinarily resorted to. With the present invention, two steps characterize the method, namely, (1) to tension the screen in place over a frame, and (2) to fuse the screening to the frame, the only requirement being that fusible materials be involved whereby the screening is fastened to the frame.

The various objects and features of this invention will be fully understood from the following detailed description of the typical preferred form and application thereof, through which description reference is made to the accompanying drawings, in which:

FIG. 1 is a perspective view of a typical screen unit;

FIG. 2 is an enlarged sectional view taken as indicated by line 22 on FIG. 1, and showing the characteristic features of the present invention as initially prepared;

FIG. 3 is a view similar to FIG. 2, and shows the installation thereon of the screening;

FIG. 4 is a schematic plan view of the apparatus provided to carry out the steps of the present invention; and

FIGS. 5, 6 and 7 are enlarged sectional views taken substantially as indicated by lines 55, 66, and 7-7 on FIG. 4.

For a proper understanding of this invention it is necessary to have in mind the nature of the frame 10 involved and of the finished screen 11 that is produced. The frame 10 is a light weight structure made up of right angularly related rails 12, adjoining in abutted relationship at mitered corners 13. The rails 12 are tubular and formed of sheet metal, and a right angle fitting (not shown) enters abutt ng rails to join them at said corners, a friction fit being provided. In order for the rail 12 to receive and retain screening S a rabbet groove 15 is provided at the inner marginal portion of the rail, and in the construction of the groove the sheet metal is overlapped and connected. in making this connection at groove 15, the outer plane of metal is turned to form a complete two-sided channel with a bottom, and the edge plane of metal is turned over the marginal portion of the metal forming the outer side of the channel. In any case, the overlapping of metal occurs at one side wall of the channel, at the inner side thereof, and the edge of the exposed overlap terminates at a downwardly faced step spaced from the bottom of the channel.

With the foregoing usual practice in mind, concerning frame construction, it is usual to force screening S into the channel forming the rabbet groove 15 using a strip or filler, this being a manual operation as hereinabove described. However, with the present invention a strip or tiller is not applied as a mechanical key to wedge the screening S in the groove 15. On the contrary, a fusible material F is initially installed in the groove 15, to occupy the same and to be connected by fusion to the screening S. In the preferred form of this invention the fusible material F is vinyl, a plastic material that is readily fused to the material forming the screening S. It is preferred, also, that the screening be made of vinyl, the same plastic material. It is to be understood, however, that a wide range of equivalent materials can be utilized and that it is possible to fuse to or around metal screening S, or other dissimilar materials, using the fusible material F. This invention is characterized by the connection of screening S onto a part of the frame 10, preferably a fusible strip of material F carried by the frame. Although said fusion can be carried out in various ways, it is preferred to employ the direct application of heat, it being understood that chemical action, for example, can be applied, if so desired.

In accordance with the invention, a frame It is acquired in assembled condition, having four rails 12 suitably joined and with a body of fusible material F, initia'lly lodged in the rabbet groove 15. Of course, the groove 15 opens in one direction exposing the material F at the face plane of the frame 10, and thus the screening S contacts the said fusible material F when brought into flat engagement with said face plane of the frame.

3 Said material F is of tubular cross-section so as to be compressed into the groove 15, it has a lip 16 to engage under the edge of metal exposed in the channel groove, and it has a projecting rib 17 to be fused into the mesh of the screening S. As shown, the rib 17 projects from the said face plane of the frame 11.

The method of this invention is practiced by: firstly stretching screening S over the frame 1%), and secondly engaging the screening with said fusible material and fusing the same together. Thirdly, the excess screening S outside of the joint made by fusion is eliminated by trimming with a sharp cutting instrument.

The first step of the method involves stretching of the screening S in a manner to maintain a flat plane thereof, and this requires the engagement of opposite marginal edges of the screening and pulling the same taut. It is usually suflicient to tension the screen from two opposite edges, and in extreme circumstances, as with large screens 11, it is feasible to tension the screen from all four edges. In any case, it is required that the screening S be at least coextensive with the frame 10, and by this it is meant that the margins of the screening 3 overlie the fusible material F to which it is to be attached.

The second step of the method involves bringing of the screening S into engagement with the fusible material F and fusing the same together. In practice, heat is the preferred means of causing the desired fusion, and there are various ways and means suitable for the application of said heat. For example, heat lamps, electronic heat generation or heat applicating irons are all feasible. Since the least complicated is the latter, the ironing means is preferable and is shown in the form of invention illustrated. Thus, a heated iron element 18 is placed in contact With the screening S at the fusible material F, and one or both (S and/or -F) are fused into engagement. Said ironing element 18 can be manipulated or mechanically controlled to press against the parts to be joined and to contact, wipe or roll over them, as circumstances required.

As a result of the two simple steps above-described, and as they are applied to the particular elements involved, a piece of screening S is readily applied to and fastened securely on a frame 10, with the screening tensioned but not in excess, all without undue strain on the frame. Further, the installation of the screening is done in one movement of attachment, said heat being applicable to the entire screen at one short time interval, for example, during but a fraction of a second.

Apparatus is provided to carry out the method hereinabove disclosed, whereby a continuous mechanized production of screens 11 is obtained. As shown in the drawings, the apparatus involves, generally, a frame feeder A, a screening feeder B, a conveyor C, a fusing means D, a trimming means E, and cutting means K. The means A through K are supported on a base indicated in the drawings shown as 20 and interrelated as later described. In order to carry out the method involved; the means A supplies random sized and/ or various shaped frames, the means B supplies screening S in a taut and continuous manner, the conveyor C operates to move the frames with screening S thereon, the fusing means D operates to attach the screening S to the frames 10, the trimming means E operates to dress the final product in the form of a screen, and the cutting means K operates to sever the screens from the supply of screening.

The frame feeder A that supplies all sizes and forms of frames 10 is not limited to any particular dimension of frame and it is such as to deliver any size frame 10, within limits and one at a time. The feeder A involves a conveyor supported stack or supply 21 of frames 10, and it involves right angularly related fences 22 and 23 to place a given corner of each of the frames being handled. The fences 22 and 23 are spaced above the supporting surface of a table 24, so as to permit delivery of one frame at a time, in'a lateral direction parallel to one of the said fences. In order to deliver the frames 10 there is a drive motor 25 that operates chains 26, and a cleat 27 extends between the chains 26 to engage and move each successive lowermost frame 10. The two chains 26 move together, between spaced shafts, to maintain alignment of the cleat 27. The motor 25 operates through a slip clutch 28 so that the frame being delivered can be held in pressured engagement with a stop rail 29. Then, as soon as each frame is removed from said pressured engagement between cleat 27 and stop rail 29, the chains are free to deliver the next successive frame 10.

The screening feeder B that continuously supplies taut screening S involves two pairs of screeen driving rollers 30-31 and 32-33. The rollers 30-31 receive screening A S therebetween from a roll R thereof, with means such as spring means to pressure the rollers into driving engagement with the screening S. The rollers 32-33 are spaced from the rollers 30-31 a distance substantially greater than-the largest screen dimension to be handled, with a spring means to pressure the rollers into driving engagement with the screen S and frame therebetween. In carrying out the invention, the rollers 32-33 are driven somewhat faster than the rollers 30-31, whereby the screening S is pulled taut between the said rollers.

In accordance with the invention, the frame feeder A delivers frames 10 intermittently and one at a time in a direction transversely .of the screening feeder B and intermediate the two pairs of driving rollers 30-31 and 32-33. As shown, the feeder A is at one side of the feeder B and with the stop rail 29 at the opposite side of the feeder B. Thus, the frames 10 are stopped in pressured engagement with the rail 29 at the said opposite side of the feeder B.

The conveyor C that moves the frames 10 with screening thereon is incorporated in the lowermost rollers 30 and 32, there being a belt 35 extending over these rollers. The belt 35 is rather narrow and located adjacent to stop rail29. The top section of belt 35 is in a plane to slidably receive and then support the frames 10 delivered by the feeder A, and it operates continuously to deliver frames with screening S superimposed thereon, issuing from the rollers 32-33.

As clearly shown, the roll R of screening S is sufficiently wide to include all screen frames 10 to be handled, that is, to overlie the material F of said frames.

The fusing means D that attaches the screening- S to the frames 10 is incorporated in the uppermost roller 33, and the roller 33 is therefore a heated roller that is thermostatically controlled. Thus, as the frames 10 pass between the rollers 32-33 pressure is applied and heat is absorbed into the metal frames 10 from the roller 33. As a result of this heat transfer there is the presence of heat to fuse the material F into the screening S, or vice versa, as the case may be. Thus, every part of the frames 10 passing between the rollers 32-33 is affected, so that both transverse and longitudinal joinders are made.

The trimming means E that dresses the final product, screens 11, is adapted to sever excess marginal portions of screening from the frames 10. Although the cutter means K operates within the functions of the trimming means E, said means B will be first described. Note that two pairs of parallel and right angularly related margins of screening S must be trimmed from each of the rectangular frames 10 handled by the apparatus. In practice, this trimming is done just outside of the line of joinder, as clearly indicated in FIG. 3 of the drawings. As shown in FIG. 4 there is a pair of right angularly related shafts 36 and 36 carrying cutters 37-37a and 38-38a, respectively. The cutter 37 follows the rollers 32-33 and is substantially aligned with the stop rail 29, so as to press onto the frame 10 at the line indicated in FIG. 3. The

cutter 37a is slidably carried on shaft 35 and is positioned therealong by means of a cam-shaped feeler 39 that engages the edge of frame 10 opposite and parallel with the edge guided by stop rail 29. A spring means 40 yieldingly urges the feeler 39 into said engagement, whereby the cutter 37a is aligned so as to press onto the frame at the line indicated in FIG. 3.

A continuation of the conveyor C follows the cutters 37 and 37a, there being a pair of driving guide rollers 41-42 to receive the screens and move them forwardly through the cutter means K later described. Said continuation of the conveyor C comprises spaced rolls 43 and 44 with a belt operating thereon to support and move the frames with screening. In order to establish tranverse right angular movement of screens, a transversely moving stop 51) is provided and which comprises a pair of transversely spaced rolls 48 and 49 with a drive belt 51 therebetween. The belt 51 can be provided with cleats, or the like, for sutficient frictional engagement with the forwardmost rail of the advancing frame it to move the screen frames laterally. In order to trim the remaining margins of the screening 5, drive rollers 52-53 are provided to receive the laterally moved frames with the screening thereon. The rollers 5253 are placed at the side of the conveyor C opposite the stop rail 29 and parallel thereto.

The cutter 38 follows the rollers 5253 and is substantially aligned with the stop 50 that moves, so as the press onto the frames 10 at the line indicated in FIG. 3. The cutter 38a is slidably carried on shaft 36 and is positioned therealong by means of a cam-shaped feeler 54 that engages the edge of the frames 10 opposite and parallel to the stop 50. A spring means 55 yieldingly urges the feeler 54 into engagement with the frame, whereby the cutter 38a is aligned so as to press onto the frame 10 at the line indicated in FIG. 3.

The cutting means K that severs the frames 10 with screening S thereon from the supply roll R is preferably a shears located intermediate the right angularly related trimming functions of the previously described means E. As shown, the cutting means K follows the cutters 37-37a just ahead of the continuation of the conveyor C, and it is adapted to slice through the screening S following passage therethrough of the frames 10. An electrical switch 56 is indicated and which electrically controls operation of the cutter K. Thus, each time a frame 10 passes the cutter means K a slicing operation is performed, thereby severing the frames 10 from the supply roll R. The frames It) with screening S thereon are then free to be moved laterally for the remainder of the trimming operation.

From the foregoing it will be seen that the method herein disclosed can be performed manually or by an apparatus such as is shown. The feasibility of the method is inherent in either case and is such as to eliminate the tedious manual application of a Wedging strip into the rabbit groove. It is clear that this invention deviates from the usual practice by employing material, fusible material, initially installed in the rails, and said installation of fusible material is readily performed by automated processes, not shown. It will be apparent that suitable drive means can be provided to rotate the chains, rolls, rollers, and various gearing hereinabove described, and in a synchronous manner whereby the apparatus operates in unison.

As a result, random sized frames, rectangular in form, are 0 handled entirely without manipulation during the process involved, namely, the installation of screening S upon frames 10 and including the removal of excess marginal portions of screening S.

Having described only a typical preferred form and application of my invention, 1 do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any modifications or variations that may appear to those skilled in the art and fall Within the scope of the following claims.

I claim:

1. Apparatus for installing screening on framing having marginal fusible material, comprising:

a horizontal conveyor belt;

means for feeding framing onto said conveyor belts;

means for feeding said screening above said conveyor belt over said framing;

a pair of upper parallel rollers, one being disposed parallel with and adjacent one end of said belt and the other being disposed parallel with and adjacent the opposite end of said belt, said pair of rollers cooperating with said conveyor belt to drive said framing and screening in the direction of movement of said belt, and one of said upper rollers rotating faster than said conveyor belt to thereby tension said screening over said framing;

and heating means for fusing said fusible material to said screening as said screening is maintained tensioned.

2. Apparatus as set forth in claim 1 wherein said heating means is associated with one of said upper rollers.

3. Apparatus as set forth in claim 2 wherein said heating means includes an additional heated horizontal roller rotatable about an axis of rotation parallel to said conveyor belt that moves across said framing and screening normal to the direction of movement of said conveyor belt.

4. Apparatus as set forth in claim 1 wherein said screening is arranged in a roll, and said apparatus further includes cutter means adjacent said conveyor belt that severs the portion of said screening overlying the margins of said framing.

5. Apparatus as set forth in claim 2 wherein said screening is arranged in a roll, and said apparatus further includes cutter means adjacent said conveyor belt that severs the portion of said screening overlying the margins of said framing.

6. Apparatus as set forth in claim 4 wherein said cutter means includes a pair of horizontal right-angularly related shafts, one of which is parallel with said rollers, each of said shafts carrying cutters engageable with the margins of said framing.

7. Apparatus as set forth in claim 6 wherein the spacing of said cutters on said shafts is adjustable.

References Cited UNITED STATES PATENTS 783,786 2/1905 Hoffman et al. -109 2,343,037 2/1944 Adelman l6l-44 2,695,445 11/1954 Johnson et al. 1401()9 DOUGLAS J. DRUMMOND, Primary Examiner,

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US783786 *Mar 25, 1904Feb 28, 1905William A HoffmanMachine for stretching wire-cloth on door or window frames.
US2343037 *Feb 27, 1941Feb 29, 1944William I AdelmanFrame
US2695445 *Jul 20, 1950Nov 30, 1954Detroit Steel Products CoMethod of screening frames by a continuous process using screening rolls
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3661188 *May 8, 1970May 9, 1972Gaug Harold EMachine for inserting wire screening
US4978414 *Dec 31, 1985Dec 18, 1990Nippon Cmk Corp.Apparatus for stretching silk including means to move cramp members independently of each other
US5272081 *Feb 4, 1991Dec 21, 1993Bar-Ilan UniversitySystem and methods for cell selection
US5310674 *Jul 29, 1991May 10, 1994Bar-Ilan UniversityApertured cell carrier
US5506141 *May 9, 1994Apr 9, 1996Bar-Ilan UniversityApertured cell carrier
US6990900Oct 17, 2003Jan 31, 2006Anderson John TMethod and apparatus for stretching and mounting a screen printing screen
US20050081726 *Oct 17, 2003Apr 21, 2005Anderson John T.Method and apparatus for stretching and mounting a screen printing screen
EP0213901A2 *Aug 22, 1986Mar 11, 1987Bar Ilan UniversityMethod for securing a microsieve to a support member and supported microsieve
EP0213901A3 *Aug 22, 1986Oct 26, 1988Bar Ilan UniversityMethod for securing a microsieve to a support member and supported microsieve
EP1068942A1 *Jul 15, 1999Jan 17, 2001Aichi Co., Ltd.Method of spreading a sheet on a frame member and method of manufacturing a chair by the sheet spreading method
Classifications
U.S. Classification156/495, 156/522, 156/583.5, 160/354, 140/109
International ClassificationB29C65/64, B29C65/00, B29C37/00
Cooperative ClassificationB29C2793/00, B29L2031/737, B29C65/7861, B29C37/0082, B29C66/534, B29C2793/009, B29C65/64, B29K2705/00, B29L2007/008, B29C66/30223, B29L2012/00, B29L2031/14, B29C66/841
European ClassificationB29C65/78M2, B29C66/534, B29C66/841, B29C65/64, B29C37/00K2