US 2284792 A
Description (OCR text may contain errors)
Juneiz, I N. A. ANDERSON BLANK HANDLING MACHINE Filed Jan. 29, 1946 4 Shee ts-Sheet 1 BY 6M 454 m: ATTORNEY J une 2,1942. N. A. AYYNDEIIRSON, 2,2
BLANK HANDLING MACHINE Filed Jan. g9, 1940 4 Shees-$het 2 INVENTOR NZ fl- ANDERSON 6142. J54,
H/5 ATTORNEY June 2, 1942- N. A." ANDER$ON FLANKHANDLING MACHINE Filed Jan. 29, 1940 4 Sheets-Sheet s .m/ 2 VBMzHII.
INVENTOR NELS f?- ANDERSON BY mjmk FU E:
H/.5 ATTORNEY Junez, 1942. ANDiERSQN r 2,284,792 f BLANK HANDLINQMAQfl INE F'iled Jan; 29, 1940 4 Sheets-Sheet 4 INVENTOR NEZS A. ANDERSON H45 ATTORNEY Patented June 2, 1942 BLANK HANDLING MA HINE Nels A. Anderson, Stockton, Calif., assignor to Fibreboard Products Inc., San Hancisco, Califl, a corporation of Delaware Application January. 29, 1940," Serial No. 316,170
v 11 Claims.
My invention relates to a machine for folding a box blank and for securing portions of the lapsed box which when 'set up has square corners and properly registered sealing flaps. A further object is to provide a folding and conveying mechanism coacting with a stitching device to maintain the blank edges properly squared-up during the stitching operation.
Another important object of my invention includes the provision of a-safety device for stopping a stitcher after a predetermined number of stitches have been made to prevent injury to the stitcher head in event a blank becomes jammed in the mechanism.
The invention possesses other objects and features of advantage, some of which, with the fore going, will be set forth in the following description of my invention. I do not limit myself to this disclosure of species of my invention, as I may adopt variant embodiments thereof within the scope of the claims.
Referring to the drawings:
Figure 1 is a plan view of a box blank upon which my machine operates; and
Figure 2 is a similar view of the blank folded and stapled in collapsed position.
Figure 3 is a side elevational view showing half of the machine; and
Figure 6 is a fragmentary perspective view of folding and fastening operations; and means for' It is to be understood that Figures 10 to 16, inclusive, are-sectional and plan views showing the blank and coacting elements at operative positions in the machine.
In the past it has been the practice to fold slotted and creased fiber box blanks, such as shipping case blanks, by hand, and feed them manually into a stitcher mechanism. Aside from the labor problem and slowness of pro duction, one of the chief difficulties was to get a uniform, properly stitched product. If a folded blank is not stitched square with edges accurately aligned, the box when finally set up willnot have square corners, or, if the untrue box is forced into square positiona gap will occur between flaps which should. otherwise abut. In order to overcome these problems I have developed a machine which automatically handles the blank material and insures the production of uniformly folded blanks, each cf which is stitched square. I
In termsof broad inclusion, my blank handling machine comprises means for feeding and conveying the blanks; means for folding the blanks while traveling through the machine; means for aligning and squaring-up the blanks during the fastening portions of a folded blank together. The latter means preferably comprises an ordinary stitcher .(or driving staples through lapping portions of the blank. A safety device is also preferably provided for the stitcher to. prevent damage to the stapling headin event ablank 1 becomes jammed in the stitcher. v ,1
In greater detail, and referring .to Figures 1 and 2 of the drawings. my preferred machine is designed to fold and stitch a fiber blank such as used for shipping cases. For example Figure 1 shows a creased-and slotted blank 2 having closure flaps 3 and a fastening tab 4. Such a blankis folded along the crease lines 6 to the collapsed position shown inFigure 2 with tab 4 underlappingt-he adjacent end wall, and the parts are secured together as by metallic staples I. The user. receives the cases in this collapsed condition' It is understood that this blank is shown merely for purposes of illustration, and
the blank engaging shoe into which the blank slides after leaving the folding mechanism.
Figure 7 is a plan view of the intermediate portions of the machine, showing the foldingv dethat my machine may be employed for folding box blanks of other kinds and in conjunction with fastening means other than a stitcher, as
will be apparent from the following description of the machine. Feeding and conveying mechanism Referring particularly to Figures 3 and 9, the fiat blanks are stacked in the machine in a hopper 8 mounted at one end of the main frame 9.
. drop varying distances.
This'hopper lies below the bed of the ;machine and has a head plate ll against which the leading edges of the blanks abut, although accurate alignment of the blanks in the stack is not necessary.. The blanks are stacked with flaps 3 leading and trailing, and with tab 4 at the back side of the machine, considering the side shown in Figure 3 to be the front.
Means are provided for lifting the top blank from the stack and for positioning its forward edge in the elevated plane of the machine bed. For this purpose a series of say four suction devices are arranged above the stack, each having a vacuum cup I! mounted at the base of a hollow stem I3 slidable within a hollow supporting tube l4. Air is withdrawn from the cup through a flexible suction hose I attached to the top of tube l4. By this telescoping arrangement the vacuum cup may drop to the level defined by the upper blank of the stack, which level of course recedes with each blank removed. Up and down movement of stem I3 is controlled by a lever ll fixed to a shaft l8 extending transversely of the frame,'and carrying a pin 19 engaging slot 2| in a link 22 pivoted to the lower .end of the stem. The lever thus elevates cup H to a predetermined level but allows the cup to After the cup has been elevated it is caused to swing forwardly about the axis of an overhead shaft 23 to which supporting tube I4 is fixed. Shafts l8 and 23 are turned by suitable crank linkages 24 and 25 actuated by cams 26 and '21 mounted on a cross shaft 23 journaled on the main frame. The latter shaft is driven by a chain, 28 extending forwardly along the frame to a shaft 31, which in turn is driven by a chain 32 from a suitable motor 33.
Suction hoses ii are connected to risers 34 from a manifold 33, and the latter is connected to a suitable vacuum pump 31 by a duct 38. A separate motor 30 drives the pump. Vacuum is impressed and released in the cups by a valve disc 4| covering an opening in the manifold; the valve being lifted by a lever 42 actuated by k ge 25 through a slotted link 43. When the valve is up and the manifold ported to the atmosphere there is no suction at the cups, as will be readily appreciated. The timing of course is such that valve 4| closes when the cups are loweredagainst a blank in the hopper.
These suction devices are preferably arranged to engage the four leading flaps of the blank, leaving a margin of flap material ahead of the vacuum cups for engagement by starter feed rolls 44 and 45 which function to advance the blank into the nip of main feed rolls 46 and 41. Lower starting roll 44 is positively driven through gears 48 from shaft 48, while upper roll 45 is freely Journaled and is mounted for up and down movementon an arm ll. This arm is pivoted on a vices have deposited the leading edge of a blank between the rolls. Fixed bars 55 having upcaught between the latter rolls the upper starter roll 45 is lifted from the blank. There are a plurality of sets of these various feed rolls spaced across the machine, say two pairs of each, to provide positive feed for the blank. After the vacuum has been released at the cups, shaft 23 turnsback to reposition tubes l4. and shaft It turns to lower the vacuum cups upon the stack. Valve 4| then closes to reestablished the vacuum at the cups.
Rolls 46 and 41 advance the blank upon a conveyor comprising a pair of chains 56 running on suitable sprockets on shafts 40 and 3|. Lugs 51 spaced along the chains engage the trailing edge of a blank and advance it along the machine bed. The pusher lugs are accurately aligned in pairs on the chains to square the trailing edge of the blank with the center line of the machine.
' Since the rear conveyor sprockets are on shaft 3| the chains are driven by motor 33; and inasthe feed rolls, roll shafts 49 and 52 being preferably geared together.
Foldina mechanism Asa blank advances along the bed it is supported adjacent the center by a T-bar '58 and adjacent the sides of the chains by angle bars 59. See Figures '7 and 10. The projecting end portions of the blank are. supported by an angle bar BI and a T-bar 62, the former having-an upstanding flange against which the edge of the blank may bear. Angie bars 63, shown in Figures '7 and 11. are. also provided above the blank to form straightedges about which the blank is folded on the crease lines .6- These latter bars are supported at their head ends only on a cross beam 64 so that the folded blank may slide off the tail ends of the straightedges.
Means are also provided on the bed to register creases 6 accurately with the straightedges. This is accomplished by a tapered strip 68 placed in the'angle of bar 6| to shift the blank laterally into proper alignment. As the blank travels along the bed it is thus gradually eased over by the tapered strip until accurate registration obtains with the overhanging straightedges. See Figure 11.
Means are provided for folding the end portions of the blank over the intermediate portions thereof. This is done while the blank is in motion by pairs of pivoted folding arms 61 having elongated nose pieces 33 therebetween for engaging the blank alongside straightedges 63. These arms swing from retracted positions underlying the path of the blank to extended positions overlying the blank, thus folding the end portions of the blank over the straightedges. As shown in Figure 8, shaft 09 of an arm in each pair has a'pinion Ii engaging a rack 12 which is reciprocated by a follower I3 riding on a cam i4 on a stub shaft 16. The latter is driven through gears "from a second stub shaft 13 carrying a turned ends function to guide the blank between I and 82 respectively. As soon as the blank is sprocket l9 meshed with a conveyor chain. A spring ll holds the ,follower against the cam; This driving of the folding mechanism from the conveyorchains simplifies the timing of, these parts.
As the blank portions are folded the portion carrying tab 4 is moved down-ahead of the other portionto obtain the underlying tab relationship. The blank portions. are guided in this lapping order by bars 32 and 33 hung by heavy springs l4 frombeam '4 to give a yleldable strucmovement.
ture. See Figures 3 and 12. These bars slope downwardly and converge in the direction of blank movement to bring the folded portions of the blank together. After being folded by arms 61 the blank passes under fixed rods 85 which keep the turned-over portion from springing up.
Thefolded blank is also confined laterally at this time by flanges 90.
In order to accommodate blanks of different size, the supporting angle bar 6| is mounted for transverse adjustment by screws 81; and the conveyor chains 56 and adjacent supporting bars 59 are mounted for like adjustment by screws 80. The folding arms, being mounted on the chain rider bars 89 as shown in Figure 8, are likewise adjusted by screws .88. Naturally the straightedges must also be adjustable, and this is provided for by slidably mounting bars 63 on cross beam 64 as illustrated in Figure 3.
Stitcher mechanism Means are provided for feeding and guiding the folded blank toward a stapling head 90 of the stitcher mechanism. As the leading edges of the folded blank leave the conveyor they are caught between pairs of feed rolls 9| and the blank is moved ahead faster than the conveyor speed to pull the blank away from the conveyor lugs so that the latter may rotate downwardly over the sprockets. As shown in Figure 4, the lower rolls are mounted on a shaft 92 drivably connected with shaft 3| by a chain 93; the upper rolls being mounted on a spring pressed shaft 94 geared to the lower roll shaft. Guide bars 82 and 83 underlying the folded portions of the blank terminate in an S-shaped channel 96 forming a pair of guideways through which the lapping edges of the blank slide. This channel is suitably fastened to the frame of the machine and thus provides support for the tail ends of the-guide bars without interfering with the blank See Figures 6 and 14. The upper and intermediate plates of the channel have upturned extensions 91 and 98 at the forward ends to insure engagement of the blank edges with the channel. The lower plate of the channel terminates in a rearwardly projecting extension 99 forming a clincher bar for the staples. This bar overlies an anvil IOI for support against the stapling blow.
' Means are also provided for squaring the folded blank under the stapling head 90 to bring adjacent edges ofthe' folded blank into registration and thereby square the folds along the crease lines. As the trailing edges of the blank leave rolls 9| these edges are engaged by a pair of pusher feet I02 each freely pivoted to a crank arm I 03 oscillated by a cam I04 through a linkage I06; the cam shaft I01 being driven from shaft 3| by a chain I05. The lower ends of pusher elements I02 rest freely on the ,bed of the machine and ride over and drop behind a blank traveling under the pusher devicesr Feet I02 then advance the folded blank against a trip I08 located in the path of the blank. Trip I08 is an element commonly associated with stitcher mechanisms and moves forwardly under the pressure of the advancing blank to start the stitcher, after which the trip is depressed to clear the blank.
Trip I09 and pusher feet I02 have normally upright opposing faces of sufiicient height to engage both layers of the folded blank, and since trip I09 offers some resistance to movement the wise compression, sufficient to true up ,the'edges if they are not in absolute vertical alignment. As shown in Figure 15, pusher feet I02 are spaced to engage the trailing edge of each overlying blank portion, and trip I09 is centrally disposed to engage the leading edges of both overlying portions. Upon driving of the first staple, trip I08 is depressed by the stitcher mechanism to clear the leading edge of the blank. A
stapling head and associated trip I09 may be of any suitable construction, and may comprise parts of the well-known "Latham stitcher mechanism. Other parts of the Latham stitcher are also preferably employed, such as trigger I09, stitch spacing feed roll III and discharge rolls H2. The stitcher partsare normally mounted on a sub-frame II3 which I preferably slidably mount on an extension II4 of my main frame, whereby the stapling head may be adjusted longitudinally of the main frame to determine the position of the first stitch relative to the blank. In accordance with the usual operation of a stitcher mechanism of this kind, the advancing blank first depresses trigger I09 which conditions the mechanism' for operation, and then pushes trip I08 which engages a clutch to start operation of the stapling head. Other mechanism of the stitcher then comes into play to rock an arm H6 and lower the upper stitch spacing feed roll II-I against the folded blank. These rolls are driven intermittently to advance the blank between stitches. -After the trailing edge'of the blank rides off trigger 'I 09 the stapling head stops and arm H6 is rocked to lower upper discharge roll H2 against the stitched blank to deliver it from the'machine.
Safety mechanism In using the Latham stitcher I have found that if a blank becomes jammed in the mechanism so as to hold trigger I09 down, the stapling head continues to drive staples in the same place and causes damage to the head. To avoid. this I provide a safety device which stops the head after a predetermined number of staples have been driven. In order to orient this device with the stitcher mechanism, Figure 5 shows trigger I09, latch arm II'I, stapling head shaft II8, cam I I9 and control lever I2I, all of which are standard parts of the Latham stitcher.
When trigger I09 is depressed by a blank it causes latch arm II! to bear against the roller end of lever I2I. Subsequent movement of trip I09 by the blank then starts the stapling head, one stitch being made for each revolution of its shaft II9. Upon rotation of shaft II8 the cam II9 depresses lever I2I and the notch of latch arm III engages over the lever roller to hold the lever down. Depression of lever I2I keeps the stapling head in operation and brings other mechanism into play to lower the stitch spacing roll III against the blank. When the trailing edge of the blank rides oil trigger I09 the latter retracts latch arm I H to release lever -I2I, which stops the stapling head and causes discharge roll II2 to be lowered against the blank.
My safety device comprises an arm I22 piv- 1 oted abouta shaft I23 journaled in the sub-frame H3. At one end of shaft I23 is fixed a ratchet I24 engaged by a pawl I26 carried by arm I22. A cam plate I2! is removably secured to the ratchet and has a series of peripheral lobes I28 adapted to engage a catch I29 on latch arm III for releasing lever I2I when a lobe rides under the catch. A suitable brake III on the other end of the shaft prevents the ratchet from overrunning.
By this arrangement arm I22 is oscillated by cam H9 and cam plate I21 is turned through an arc defined by one ratchet tooth for each revolution of shaft l l8. Thus, the distance between lobes I28 limits the number of stitches that can be made before the'stapling head is stopped, should a blank become stuck in the mechanism. With the twelve lobed cam shown in Figure 5 the stapling head'will be stopped after five staples have been driven. By replacing cam plate I21 with one of the same diameter but having a different number of lobes, the stapling head may be stopped after a greater or less number of stitches, depending upon the spacing between the lobes.
While I have chosen to show a stitcher mechanism in conjunction with my blank feeding and folding mechanism it is understood other fastening means, such as a taping device, may be employed for securing the edges of the folded blank together.
The operation of my machine has been described largely in connection with a single blank, but it is understood that blanks follow each other in rapid succession through the machine. Conveyor chains 56 move continuously and lugs 51 are spaced therealong to engage the blanks as fast as they are deposited upon the conveyor by the feeding mechanism, the spacing of the lugs being such that they engage the trailing edge of a blank upon emergence from the nip of feed rolls 46 and 41. -While a blank has'an intermittent motion in the stitcher the seriesof stitches are made very rapidly in the Latham unit. Furthermore, the speeding up of the blank by rolls 9| prior to entering the stitcher allows for a certain amount of lost time in the stitching unit before the next set of conveyor lugs bring up another blank. The conveyor chains are thus enabled to move continuously.
l. A machine for handling a blank, comprising means for folding the blank, elements between which the folded blank is compressed for registering adjacent edges of the blank, and means controlled by one of said elements for fastening portions of the folded blank together.
2. A machine for handling a blank, comprising means for folding the blank, means for stitching the folded blank, a trip engageable by the blank for actuating the'stitching means, and means associated with said trip for squaring the fold prior to stitching,
3. A machine for handling a blank, comprising a conveyor chain for moving the blank, means adjacent the conveyor for folding the blank, and means actuated by a drive sprocket meshed with the conveyor chain for operating the folding means. i
4'. A machine for handling a blank, comprising means for moving the blank, means for folding portions of the blank into lapping relation, and an S-shaped element. providing a g-uideway tlgrough which the lapping portions are slida le.
5. A machine for handling a blank having a crease, comprising means for moving the blank along a path, a straight edge, means for shifting the blank transversely of said path while the blank is in motion to register the crease with the straightedge, and means for folding the blank over said straightedge.
6. A machine for handling a blank having a crease, comprising means for moving the blank along a path, a, fixed member having a surface angularly disposed to said path and engageable with an edge of the blank for shifting the blank transversely of said path while the blank is in motion to register the crease with the straightedge, and means for folding the blank over said straightedge.
7. A machine for handling a blank having portions adapted to be folded over the body of the blank with the ends of said portions overlapped, comprising means for moving the blank along a path, means for folding said portions, means for guiding said portions into predetermined lapping relation, means for applying pressure across opposite edges of the folded blank to square the folds, and means for fastening the lapping portions together.
8. A machine for handling a blank having portions adapted to be folded over the body of the blank with the ends of said portions overlapped, comprising means for moving the blank along a path, means for folding said portions, a pair of guide bars above said path for guiding said portions into predetermined lapping relation and spring means for resiliently suspending said bars.
9. A machine for handling a blank having portions adapted to be folded over the body of the blank with the ends of said portions overlapped, comprising means for moving the blank along a path, means for folding said portions, and a pair of angularly disposed guide bars arranged above the path and converging toward one end of the machine for guiding said portions into predetermined lapping relation.
10. A machine for handling a blank having portions adapted to be folded over the body of the blank with the ends of said portions overlapped, comprising means for moving the blank along a path, means for folding said portions, a pair of separate guide bars arranged above the path for guiding said portions into predetermined lapping relation, means for supporting the bars at one end, and a terminal element connected with the other ends of said bars and providing a guideway along which the lapping ends of said portions are slidable.
11. A machine for handling a blank, comprising means for moving the blank along a path, means adjacent the path for folding the blank, an element pivotally mounted above the path and arranged to be lifted by said blank and to ride over the blank and drop behind the trailing edges thereof, and means for moving the element forwardly against said edges to square the fold.
NELS A. ANDERSON.