US2970527A - Flange bending machine for unstayed set-up box manufacture - Google Patents

Description

c. T. FISHER Feb. 7, 1961 FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE 8 Sheets-Sheet 1 Filed March 20, 1958 INVENTORZ CHARLES T FISHER ATTYS.

8 Sheets-Sheet 2 C. T. FISHER FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE Feb. 7,1961

Filed March 20 C. T. FISHER Feb. 7, 1961 FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE Filed March 20, 1958 8 Sheets-Sheet 3 agn- INVENTOR CHARLES T. FISHER C. T. FISHER Feb 7, 1961 FLANGE BENDING MACHINE FOR UNSTAYEID SET- UP BOX MANUFACTURE 8 Sheets-Sheet 4 Filed March 20, 1958 ATTYS.

INVENTORI CHARLES T. FISHER FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE Filed March 20, 1958 I 8 Sheets-Sheet 5 INVEINTOR CHARLES T. FISHER BJWW ATTYS 8 Sheets-Sheet 6 WWW ATTYS.

C. T. FISHER FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE Filed March 20, 1958 Feb. 7, 1961 C. T. FISHER Feb. 7, 1961 ,970,5Z7

FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE I 8 Sheets-Sheet '7 CHARLES Filed March 20, 1958 ATT'YS.

Feb. 7, 1961 c. T. FISHER 2,970,527

FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE Filed March 20, 1958 8 Sheets-Sheet 8 (fig/4. (fig/5 fy/d b a /0/ M3 /0/ mg mg INVENTORI CHARLES T. FISHER BY WW AT T YS.

FLANGE BENDING MACHINE FOR UNSTAYED SET-UP BOX MANUFACTURE Charles T. Fisher, Batavia, N.Y., assignor to Harvey M. Crockett, Willow Grove, Pa.

Filed Mar. 20, 1958, Ser. No. 722,764

6 Claims. (CI. 93-51) This invention relates to a machine for forming flat sheets or blanks of paper or cardboard or other material into box form and which may subsequently be wrapped with a gummed wrap to provide a finished box.

The fiat blanks employed in the machine are die-cut to shape and are marginally pro-scored, the score measure determining the ultimate size of the box.

More particularly, the invention is adapted for use in unstayed work, wherein the Wrap alone is relied upon to secure the sides thereof with requred rigidity and strength. This is especially true of boxes in the smaller sizes where closer tolerances as to fit between the box proper and the lid preclude the use of corner stays, and furthermore, as in the manufacture of fancy boxes, where in the use of stays would cause unsightly tell-tale stay protuberances in the wrap cover, and thus adversely affect the appearance and desirability .of the finished product.

ther applications of use will be found to be particularly advantageous also, as in the manufacture of boxes or containers that are not wrapped, but have their respective side walls secured at the corners of the box with stays or strips of material other than paper. For example, a very widely used box employs a metallic angle edging at each corner of the box to secure the adjacent sides thereof.

Still another application of use would be in the manufacture of some plastic containers, and particularly boxes formed from acetate sheets or blanks, wherein the de walls of such boxes would be secured by heat-sealing.

But whatever the method employed to secure the side walls of a particular box, it is the primary purpose of the subject invention to so form the box blank that the end product will be characterized by the precision with which the flanges are bent permitting boxes and lids alike to fit with minimum practical tolerances, and providing accurately formed and squared corners that insure a finished article entirely free from any warped or buckled surface.

Heretofore, the customary practice of forming such boxes has been to bend the marginal portions of the prescored blank upwardly at the score line by hand to form the side and end flanges comprising the sides and end walls of the box proper or lid therefor, respectively. This is not only costly as to the time factor involved, but also because skilled labor is required to form boxes free from the defects mentioned above, for unless extreme care is taken in securing a bend of correct amplitude at the score line and at the same time one that is truly square, the finished box will be distorted to the degree that it will exhibit a tendency to buckle, and in the case of the more shallow types, the box proper and lid will not stay together in assembly. Insuflicient bending or inadequate and/or uneven pressure during bending will likewise adversely affect a box thus formed, in that the side walls thereof will flare outwardly in the finished article rather than maintain a truly perpendicular relationship.

These factors are critical in todays competitive market,

2,970,527 Fatented Feb. 7, 1951 particularly when new materials are being used in the manufacture of such boxes and containers, and since the degree of bend required to produce a. uniformly satisfactory box varies as to the type and thickness of the material used.

Accordingly, another objective of the present invention is to prov.de adjustable means whereby the degree of bend imparted to the flanges of the blank, as well as the pressure applied to the flanges during the bending operation is controlled precisely in order to insure a uniform end product regardless of material characteristics.

It is also customary in the method of hand forming, to stack the formed boxes in readiness .for the operator of the machine performlng the finishing operation. Such stacking permits the boxes to nest in each other to the extent that they stick together, with the resultant loss of time on the part of the operator in separating the boxes thus nested and consequent loss of production.

For the purposes of this application, the invention will be illustrated in conjunction with a wrapping machine, although it will be understood that there are other types of machines for purposes other than wrapping to which the present machine would be a valuable adjunct. In such a combination the operation of the box-forming ma.- chine of the subject invention would be timed or synchronized with the machine performing the end operation.

Accordingly, another object of the invention is the provision of means for controlling the machine of the subject invention for sequential operation conjunctively with a second machine, such as a wrapping machine, so that a forming operat on is completed for each cyclic operation of said second machine. Through this arrangement, each time a box is completed in the wrapping machine there will be a formed box in readiness for continued operation of the wrapper. In event of wrapper machine stoppage, the forming machine will also be shut down with no accumulat on of boxes resulting. Operation in this manner also eliminates the need of stacking formed boxes prior to wrapping or finishing, and the attendant handling thereof.

.Still another object is the provision of an automatic box-forming machine that will have the capacity to supply completely formed boxes directly to the wrapp ng machines equipped with high-speed automatic feed devices at a rate consistent with the maximum operational speed of said feed devices.

A further object of the invention is the provision in a machine of the character descrbed of a one revolution clutch controlling each cycle of operation.

Another object of the invention is the provision of means for feeding flat paper blanks to a flange-bending station, and means for sequentially bending the side and end flanges to form an unstayed box suitable for application to the forms of a box-wrapping machine without further condltioning.

A still further object of the invention is the provision of plunger means for preforming a flat blank into box forms and means for bending the side and end flanges or panels of the box inwardly to produce a definite fold at the score line of the blank.

Still another object of the invention is the provision in a box forming means of means for sequentially bending the side and end panels of the box inwardly and means for preventing panel interference during such bending.

A further object of the invention is the provision in a box machine of the character described of suction means for holding the blank firmly in position during bending.

Another object of the invention is the provision in a box machine of the character described of means for directirig air-blast against formed sides to prevent panel interference during bending of the panels or flanges.

A still further object of the invention is the provision in a box machine of the character described of cam means for actuating the blank feeding means and the box forming means, motor means for driving the cam means, and a one-revolution clutch between the motor means and the cam means. 4

Other objects of the invention have to do with the adjustability of various devices of the machine to en able the'forming of boxes of different sizes.

Other objects and advantages will be apparent from the following description of the preferred embodiment of the invention illustrated in the accompanying drawings, in which:

Fig. 1 is a more or less diagrammatic side elevation of a box forming machine constructed in accordance with the invention;

Fig. 2 is a fragmentary end elevation of the lower portion of the machine as viewed from the right in Fig. 1;

Fig. 3 is an enlarged fragmentary end elevation taken as indicated by the line 3-3 in Fig. 1;

Fig. 4 is an enlarged side elevation of the upper portion of the machine;

Fig. 5 is a plan view of Fig. 4;

Fig. 6 is a still further enlarged sectional elevation taken substantially on the line 6-6 of Fig. 5;

Fig. 7 is a transverse sectional plan view taken as indicated by the line 7-7 in Fig. 6;

Fig. 8 is an end elevational View as viewed from the right in Fig. 6; i

Fig. 9 is a fragmentary vertical section taken on the line 99 of Fig. 5;

Fig. 9a is a fragmentary vertical sectional view taken on the line 9a, Fig. 6;

Figs. 10 to 13 inclusive, are longitudinal sectional views taken substantially on the line 66 of Fig. 5 and illustrating various steps in the operation of the machine;

Figs. 13a and 13b are enlarged fragmentary views illustrating details of the bending operation.

Fig. 14 is a perspective view of one of the blanks employed in the machine;

Fig. 14a is a perspective view illustrating a step in the forming operation;

Figs. 15 to 19, inclusive, are similar views illustrating various steps in the formation of a box from the blanks of Fig. 14a;

Fig. is a schematic view illustrating a machine of the present invention associated with a well-known type of box wrapping machine for applying gummed wraps to the formed boxes;

Fig. 21 illustrates the timed relation of the earns located on one cam shaft; and

Fig. 22 illustrates the timed relation of the cams located on a second cam shaft.

Referring to the drawings the machine comprises in general suitable framework F, a drive motor M, a magazine A for a stack of cardboard blanks B of the form illustrated in Fig. 14, a feed table FT, a blank pusher bar P, feed rolls R, guide rails G for guiding the blanks from the feed rolls to a box forming station S, an upper box forming plunger U, an associated lower box forming plunger L, a pair of opposed side slides or flange benders SS and 85-1, a pair of end slides or flange benders ES and ES-1, a cam shaft CS, a one-revolution clutch RC of well-known type, such as a Hilliard clutch, associated with the cam shaft CS, and a second cam shaft CS-Z in one to one drive relationship with the cam shaft CS, a pressure valve V and a suction valve SV.

One of the blanks B employed in the machine is illustrated in Fig. 14 and it will be seen that it has corner notches a at the ends of the marginal portions b and that it is scored as indicated by the broken lines c. These score lines are referred to in this art as denoting the score measure of the blank. e marginal portions of the blank when bent into upright position form the sides and ends of the box and are hereinafter referred to as side and end flanges.

The drive motor M has a pulley and belt driving connection 5 with a countershaft 6, mounted in bearings 6a supported on the cross-members 7 of the framework F. The countershaft 6 has a pulley and belt driving connection 8 with a lay shaft 9.

The lay shaft 9 has a sprocket and chain driving connection 9a with the lower feed roll R, and this lower feed roll is drivingly connected with the upper feed roll by gear train 10. The lay shaft 9is drivingly connected to a second lay shaft 11 by means of gear train 12 and this second lay shaft is drivingly connected to the one revolution clutch RC by means of gear train 13.

The one revolution clutch RC is mounted coaxially with the cam shaft CS and this cam shaft is drivingly connected to the cam shaft CS2 by the sprocket and chain driving connection 14.

A suitable starting switch controls the motor M, and a clutch device such as the hand lever operated jawclutch 15 is provided to drivingly connect and disconnect the motor from the lay shaft 9. Whenever the motor is running with the clutch 15 engaged, the feed rolls R, R are rotated as is also the driving element of the one-revolution clutch. However, when the trip disc 16 of the one-revolution clutch is held in latched position by the latch 17, as shown in Figs. 6 and 7, the clutch is disengaged from the cam shaft CS and no rotation is imparted to the cam shafts CS and CS-2.

The latch 17 is actuated by a solenoid 18 which is activated by a control switch 19 which, as shown diagrammatically in Fig. 20, is associated with a moving part, such as the plunger 20 of a box-wrapping machine of well known type. This plunger operates to close the switch 19 once for each box wrapped with the result that each time a box is wrapped the solenoid 18 is energized to trip the one-revolution clutch. This causes rotation of the cam shafts CS and CS-2 through one revolution to complete a cycle of operation of the machine in which a box is formed in readiness for application to the forms of the wrapping machine.

It will be seen from the foregoing that through this arrangement for each box wrapped in the wrapping-machine a new box is formed in the machine of the present invention, or stated in another way, the two machines are synchronized for what may be termed a one for one operation.

It is to be understood that in instances where independent operation of the machine of the present invention is desirable the control switch 19 can be coriveniently located for manual actuation.

The magazine A is provided with upright side plates 24 carried by brackets 25 which are adjustable along the upright face plate 26 of the machine framework thus enabling adjustment of the width of the magazine to accommodate blanks of different widths (Figs. 4 and 5). A vertically adjustable gauge bar 27 is mounted in the face plate 26 whereby the gap 27a (Fig. 11) for the passage of blanks may be adjusted to suit the thickness of blanks being used. This adjustment is made by means of an adjusting screw 28 mounted in a bracket secured to the face plate 26. An adjustable upright guide post 29 engageable in a corner notch of the blanks is provided to stabilize the stack of blanks.

The cam shaft CS has secured thereon a pusher cam 30 for actuating the pusher P through the medium of a cam follower 31 carried by the pivoted lever 32 which is connected at its free end 33 to one end of a link 34. The other end of the link 34 is connected to one arm 35 of a compound lever pivoted at 36 in a block 37 carried by the framework F. The other arm 38 of the lever is connected by a link 39 to the depending lug 40 of the pusher slide bar 41. The bar 41 is slidably nested in a '5 channel shaped guide member 42 secured to the underside of a table plate 43. The plate 43 is fixedly secured to the side plates 44 of the framework F by side bars 45. The pusher bar P is adjustably secured, adjacent its right hand end, to the slide bar 41 by a block 46 and clamp plate 47.

By means of the above connections reciprocatory movement is imparted to pusher bar P, it being pointed out that in each cycle of operation, i.e., in a complete revolution of the pusher cam 30 from its normal rest position, the pusher bar first moves inwardly from the position of Figs. 4 and 6 to the position of Fig. and then returns outwardly to the position of Figs. 4 and 6.

Also secured on the cam shaft CS is a feed cam 50 for actuating the feed table FT through the medium of a cam follower 51 carried by an arm 52 which is connected at 53 to a pivoted lever 54. The bifurcated end 55 of the link 52 guidingly embraces the cam shaft CS. A link 56 is connected at one end to the free end of the lever 54 and at its other end to a pin 57 carried by a bracket 58 secured to the feed table by a screw 59 (Fig. 5).

By means of the above connections reciprocatory movement is imparted to the feed table FT, and in each cycle of operation, i.e. in a complete revolution of the feed cam 50 from its normal rest position, the feed table moves first outwardly from the position of Fig. 6 to the position of Fig. 11, and then returns inwardly to the position of Figs. 6 and 13.

The feed table FT has a stripper blade 60 adjustably secured on its upper face by a clamp or strap 61 which overlies the blade 60 and secures said blade in clamping relationship to said table on the side guides 62 by screws 63, 63 (Figs. 3 and 5). Since the feed-stroke of the table remains the same regardless of blank size, the screws 63, 63 provide readily accessible means for adjusting the blade 69 relative to the stack.

When the machine is in its neutral or rest position, i.e. at the end of a cycle of operation, the stack of blanks B rests supported at its forward lower edge on the feed table and on a pad 43a, said pad being secured to the fixed table plate 43 and confined in a recess provided in the forward edge of the feed table. The pad 43acomplements the gauge bar 27, the top surface thereof coextensive with the surface of the feed table providing a datum point when making an adjustment of the gauge bar 27. The gap between the two as prescribed by the gauge bar setting and designated 27a is usually adjusted to one and a half times the thickness of a blank to preclude the passage of more than a single blank therebetween at any one time. At a point adjacent the rear of the stack, additional support is provided by the stripper blade 66'. (See Figs. 6 and 10.)

When the clutch RC is tripped to initiate cyclic operation of the machine, the feed table with associated blade 61 begin a retractive movement relative to the stack B, tothe position of Fig. ll in which the shoulder 64 of the stripper blade is moved out from beneath the stack to an extent clearing said stack. Return of the feed table, terminating the feed stroke, effects engagement between said shoulder 64 and lower blank of stack, stripping said blank from the bottom of the stack and passing it into the nip of the constantly rotating feed rolls R, R. The rolls advance the blank, discharging it onto the supporting ledges 65, 65 of a pair of spaced parallel longitudinally extending guide rails G, G to a "position of rest immediately in front ofthe retracted pusher bar P. (See Fig. 13.) This completes a cycle of feed table operation.

It will be noted that in the retractive position of the feed table and associated stripper blade 60, the relatively fixed pad 43a supports the forward edge of the stack B independent of the feed table, maintaining the gap 27a constant with respect to the gauging bar 27. Also during this retractive movement of the feed table, the guide post 29 serves to retain the stack within the confines of the face plate 26 and the side plates 24, 24 of the magazine.

Since the pad 43a is relatively narrow the feed table in its return stroke supplements the action of the stripper blade due to the frictional contact between the table surface and the forward edge of the stack which lies to either side of the gauging pad 43a. (See Fig. 9a.) Such supplemental action reduces the contact pressure between the shoulder 64 of the blade and edge of blank being fed and eliminates consequent damage to said edge when blanks are formed of very thin or fragile material.

The pusher cam 30 and the feed cam 50 are so relatively positioned on the cam shaft CS, as will be seen from Fig. 21, that when the clutch RC is tripped for the next cycle the pusher bar P is actuated to transfer the blank just fed to the guide rails and along the said guide rails from the position P-l of Fig. 6, to the position P2 of Fig. 10 to the box forming station S where it comes to rest between the upper and lower box forming plungers U and L respectively.

In order to prevent the blank from over-shooting the station S, adjustable stops 66, 66 engageable by the notched forward corners of the blank, are provided on the guide rails G, G. The blank is thus positioned at the station S in proper relation to the box forming plungers V and L and to the slides SS, SS-L Es, and ES-l.

It is here noted that when the blank approaches the station S it pushes the previously formed box away from the station as shown in Fig. 10. In order to prevent any possibility of hook-up of the discharging box, a supporting strip 48 is provided for guiding the box as it is moved out of the machine, since a formed box is no longer supported on the guide rails 65.

Upon continued rotation of the pusher cam 30 the pusher bar is returned to its starting position to com- .plete a cycle of operation of the pusher bar. It will be noted that the lower feed roll is grooved at 67 to enable the pusher bar to pass between the feed rolls.

When the pusher bar has completed its cycle of operation the feed table has also completed its cycle thus depositing the next blank on the guide rails ready to b fed along the rails when the clutch RC is next tripped.

The cam shaft (IS-2 has secured thereon a cam 70 for vertically reciprocating the upper box preforming plunger U through the medium of a cam follower 71 carried by an upwardly extending telescopic spring-loaded actuating rod 72 having a bifurcated lower end 73 adapted to embrace the cam shaft and having its upper end connected at '74 to one end of a lever 75 pivoted at 76 in a fixed bracket 77.

The bracket 77 is secured to a table plate 78 of the machine framework by screws 79. The opposite end of the lever 75 is connected to the plunger U by a suitable vertically adjustable swivel connector d9. A tension spring 81 maintains the cam follower 71 in contact with the cam 70.

The plunger U is provided at its lower end with a flat platen 82 the dimensions of which as to length and width are preferably slightly less than the score dimensions of the blanks. The bracket '77 is provided with an upright bearing portion 83 in which the plunger U has a sliding fit.

Reverting now to the cam shaft CS it will be seen that a cam 85 is secured thereon for vertical reciprocation to the lower box preforming plunger L through the medium .121 carried on the respective slides.

The plunger is hollow and has sliding fit in the upright support 95 which is secured to the bottom table plate 89 by bolts 96. 'A stop lug 97 having an adjusting screw 98 engageable with the table plate 89 is provided on the plunger L to limit the upward movement thereof. A

. hose 99 connects the hollow plunger to the vacuum valve SV for a purpose hereinafter appearing.

The upper plunger cam 7 and the lower plunger cam 85 are so relatively positioned on their cam shafts, as will be seen from Figs. 21 and 22,that in a cycle of op eration thereof, i.e., in one revolution of the cams from neutral or rest position, the upper plunger is first moved downwardly by its cam 70 from the position of Fig. 6 until it clamps the blank, at position P-2 in Fig. 10, between its platen and the suction head of the lower plunger. When the upper plunger arrives at this clamping position the plunger yields because of the spring loading of the actuating rod 72.

Then the upper plunger continues in its downward movement as the lower plunger is also moved downwardly by its cam 85, thus causing both plungers to move downwardly together with the blank clamped therebetween. In this downward movement the marginal or flange portions of the blank are turned upwardly because of their engagement with the side and end slides SS, SS-l, Es and ES-l, thus forming side and end flanges or panels 100, 101, 102 and 103 of the box as clearly shown in Fig. l1.

Next the upper plunger is moved upwardly to its top position but the lower plunger dwells in its down position until after the side and end slides have performed their bending operations in the manner to be hereinafter described. It should be noted here that the lower limit position of the plunger L is prescribed by the collar 91 which, when moved to said lower position by the plunger cam 85, comes to rest lightly against the opposed upper end face of the plunger support member 95. In this lower position the top or working surface of the suction head 93 should lie in a plane intersecting the under surfaces or ironing faces of the nose elements 120, This relationship thus established is zero setting.

7 Any adjustment of the suction head from this position to compensate for thickness of the blank or to regulate the pressure applied thereto, at the time of setting up the machine for a run, is provided by means generally indicated at 93a; Such means may be calibrated in obvious manner to facilitate adjustment.

Referring particularly to Figs. -13, the four slides above-mentioned function to bend the side and end flanges or panels of the box inwardly so as to produce definite folds 'at the score lines of the blanks. This folding produces definite corner bends at the score lines which cause the side and end flanges of the box to spring into upright position upon retraction of the bending slides thus resulting in the production of an unstayed box having substantially vertical side and end walls which can be readily applied to the forms of a wrapping machine without further conditioning.

It should be noted here that the action of the slides ineffecting a correct and desirable bend, is accomplished by turning the flange of the box back upon itself to a degree suflicient that the inherent resistance of the blank material'to bending, will return the said flange to a truly vertical position when freed. (See Fig. 19.)

However, the degree to which a flange is bent to attain this result is not the same for all kinds of materials. It will vary also as to the thickness of the material used. Degree of pressure applied at the hinge point of the bend is also a factor. In some instances it has been found necessary to bend the flange back until it lies flat upon the main panel of the blank itself, or through an arc of at least l80, and in more stubborn cases to iron the bend flat under substantial pressure, applied between the nose 10f slides and the blank supporting plunger L..

'a suction head 93 having a plurality of suction holes 94. I

-: Figures 13:: and- 13b illustrate two-different settings or adjustments of the slide and plunger relationship to demonstrate this point, each set for different operational conditions, but each result in an end product as exemplified by the showing of Fig. 19. v

In order to hold the box in place during the flange bending operation suction is applied to the suction head 93 and in order to prevent flange interference during the bending operation air blasts are directed against the side flanges to insure of their remaining in upright position. The manner of applying the suction and air blasts and the manner in which the slides are actuated in sequence will now be described.

In and out movement is imparted to the side slides SS by a cam secured on the cam shaft CS2 through the medium of a cam follower 111 carried at one end of a spring biased lever 112 pivotally mounted at 113 on a bracket 114 secured to the table plate 78 by bolts 115. The other end of this lever is connected to the slide SS by a link 116.

The slide SS as well as the three other slides employed (Figs. 9-13) each comprises a top and bottom plate 117 and 118 adjustably secured together by a screw and slot connection 119 and a nose member 120 having a rounded flange engaging face 121. The slides are slidably mounted in a plane directly below the plane of the guide rails G in slideways provided by slots in the table plate 78 and by the gibs 122. The bottom plates 118 have depending ears 123 for attachment of slide actuating links.

In and out movement is imparted to the other side slide SS1 by a cam 125 secured on the cam shaft CS-2 through the medium of a cam follower 126 carried at one end of a spring biased lever 127 pivotally mounted at 128 on a bracket 129 secured to the table plate 78 by bolts 130. The other end of this lever is connected to the slide SS-l by a link 131.

In and out movement is imparted to the end slide ES by a cam secured on the cam shaft CS-2 through the medium of a cam follower 136 carried at one end of spring biased lever 137 pivotally mounted at 138 on a bracket 139 secured to the bottom table plate 89 by bolts 140. The other end of this lever is connected to the slide ES by a link 141.

In and out movement is imparted to the other end slides ES-l by a cam secured on the cam shaft CS through the medium of a cam follower 146 carried at one end of a spring biased lever 147 pivotally mounted at 148 on a bracket 149 secured to the upper table plate 78. The other end of this lever is connected to the slide ES-l bya link 150.

By referring to Figs. 21 and 22 it will be seen that the slide actuating cams 110, 125, 135 and 145 are so relatively positioned on the cam shafts that the slides .are actuated in the following sequence SS, SS-l, ES and ES-l.

It is to be observed that when the slides move inwardly to perform their flange-bending operation the nose members 120- thereof fold the flanges tightly against the bottom of the box as shown in Figs. 12 and 13 so as to produce the definite folds above referred to which are essential to the production of a properly formed unstayed box suitable for use in a wrapping machine without further conditioning.

.The holding of the boxes in place and the directing of air blasts against the sides of the boxes during the above bending operations are accomplished in the following manner.

The suction head 93 is connected by means of the hollow plunger L and hose 99 to the suction valve SV of a dual vacuum and pressure pump of a wellknown standard type. A hose line 154 connects the suction valve to the vacuum side of the dual pump 155.

The suction valve is controlled by means of a cam 156 secured on the cam shaft CS2 which actuates' the springbi'ased valve'stem 157 through the medium of a cam follower 158 carried by a lever 159 pivotally mounted at 160 on the side plate 44 of the machine framework. The suction valve is of standard form operating when the valve stem is depressed to disconnect the suction line 99 from the source of suction and when the valve stem is released to connect the suction line with the source of suction.

The suction cam 156 is so positioned on the cam shaft .CS-Z with relation to the plunger and slide actuating cams that suction is applied to the suction head just prior to the time that the upper platen contacts the blank and prior to the time that the first slide SS is actuated. The suction cam then holds the suction on until after the fourth slide ES-l has completed its bending operation and until just before the suction head is returned to its uppermost position.

The admission of air pressure to the nozzles 165 and 166 for the purpose of directing air blasts against the side flanges of the box is controlled by the air pressure valve V which is actuated by a cam 167 secured on the cam shaft CS2. The cam 167 actuates the valve V by means of a cam follower 168 carried at the upper end of the spring loaded valve stem 169. The cam profile is such that the valve is moved to three operative positions, namely, a central or neutral cut-off position, an upper position in which air pressure is admitted to the nozzle 165 and a lower position in which air pressure is admitted to the nozzle 166.

Referring in particular to Figs. 6 and 8, it will be seen that when the cam follower 168 operates on a concentric cam surface 170 the valve is in the cut-off position of Fig. 8. In this position the pressure lines 171 and 172 leading to the nozzles 165 and 166, respectively, are blanked off to prevent admission of air under pressure thereto. As the cam rotates in counterclockwise direction the cam follower will move to the low point 173 of the cam thus moving the hollow slide valve 174 upwardly to bring its port 175 into registry with the pipe line 171 so as to admit air under pressure to the nozzle 165. Thus a sharp blast of air is directed against the previously upwardly bent box side flange 100 to insure of its standing in upright position. As the cam continues in its rotation the high lobe 176 of the cam moves the slide valve 174 downwardly to bring its port 177 into registry with the pipe line 172 so as to admit air under pressure to the nozzle 166. Thus a sharp blast of air is directed against the previously upwardy bent box side flange 101 to insure of its standing in upright position. As the cam continues in its rotation the cam follower again rides the concentric cam surface 170 thus moving the slide valve back to cut-oflf position. The hollow slide valve 174 is connected to the pressure side of the dual pump 155 by a hose line 178. The dual pump has belt and pulley drive connections 153 to the motor M.

The feature of directing air blasts in the manner just described is particularly advantageous when boxes having relatively high flanges or walls are being formed. Directing of an air blast against the first side flange prior to bending the second side flange prevents any possibility of flange overlap when bending the second side, and by then directing an air blast against the second side flange, flange interference when bending the end flanges is prevented.

Referring to Figs. '21 and 22 it will be seen that the cam 167 is so positioned on its cam shaft with respect to the other cams above described that the air blast is directed against the first side flange 100 as its slide SS moves outwardly and that the air blast is directed against the second side flange 101 as its slide SS-I moves outwardly.

Reverting now to the adjustability of the various parts in order to readily adjust the machine to produce boxes of different sizes it has been pointed out above that the sides of the magazine can be adjusted as to width, that 10 the guide post 29 is adjusable to suit the length of the blank and that the gauge bar 27 is vertically adjustable to alter the height of the gap 27a to suit the thickness of the blank.

By loosening the clamp plate 47 and adjusting the pusher bar P on the pusher slide bar 41 the point at which the front edge of the pusher bar stops in its forward travel can be adjusted.

By loosening the strap 61 and adjusting the position of the feed blade 60 on the feed table FT the point to which the stripper blade shoulder 64 is retracted in the outward travel of the feed table can be adjusted.

The guide rails G, G are adjustable as to lateral spacing by loosening the screws 68 and adjusting. the rail carrying plates 69 inwardly or outwardly, it being noted that the plates and guide rails are maintained in parallel relationship by means of the parallel transverse tongue and grooves 69a.

The spaced relation of the side slides SS and 88-1 and the end slides ES and ES-l can be adjusted by means of the screw and slot connections 119. This adjustment not only enables adjustment for producing boxes of different sizes but also enables adjustment of the amount the slide noses overlap the blank in the flange bending operations. Thus the amount of pressure transmitted to the flanges can be adjusted. For example, when employing heavy or poorly scored blanks the noses are adjusted more closely together than for lighter well scored blanks.

In adjusting the machine for different sizes of blanks, platens 82 and suction heads 93 of proper size are employed. Blanks of diflerent thickness can be accommodated by means associated with the lower plunger head 93. It is pointed out that no change of the various cams is necessary when adjusting the machine for boxes of different size.

Referring to Figs. 15-19 it will be seen that Fig. 15 illustrates the first flange-bending step, by the slide SS, in which the side flange is bent inwardly with a definite fold 100a at the score line. Fig. 16 illustrates the second flange bending step, by the slide 88-1, in which the opposite side flange 101 is bent inwardly with a definite fold 101:: at the score line and in which the flange 100 has sprung to its upright position. Fig. 17

illustrates the third flange-bending step by the end slide ES, in which the end flange 102 is bent inwardly with a definite fold 102a at the score line and in which the side flange 101 has sprung to its upright position. Fig. 18 illustrates the fourth flange bending step, by the end slide ES-l, in which the opposite end flange 103 is bent inwardly with a definite fold 103a at the score line and in which the end flange 102 has sprung to its upright position. Fig. 19 illustrates a completely formed box.

It has been found from actual experience that unless such definite folds are made, an unstayed box suitable for effective use in a box wrapping machine will not be produced.

Having completed a description of the operation of the subject machine, it will be obvious from the foregoing that it is capable of producing formed boxes in a variety of sizes and materials that will be entirely free from such defects as buckling, flared side Walls and the like, that ordinarily are not consistently obtainable when formed manually. And that such a machine is capable of delivering such work at a rate consistent with the high productivity of modern wrapping machines and the like, to the extent that it may be coupled thereto to form an integrated unit of the manufacturing battery, thus elimiating the handling and storage of blanks that characterlze present operations.

While certain constructions have been employed in the machine for accomplishing a desired result it will be obvious that others might equally well be used for the purposes set forth. Accordingly the invention as del -1 scribed-and illustrated is not -to'be limited except as to the scope of the claims appended hereto.

I claim:

1. A box forming machine comprising means for feeding flat blanks to a box forming station, plunger means for preforming the blanks into a box having a base and side and end flanges, means on said plunger means to support the base of said box blank, a pair of opposed slides for bending-the side flanges inwardly into overlying relation with said base, a second pair of opposed slides for bending the end flanges inwardly into overlying relation with said base, said slides cooperating with said support means to provide definite folds for the flanges, a movement-imparting means adapted to reciprocate said side flange slides into said .overlying relation when said end flange slides are out of overlying relation, and adapted to reciprocate said end flange slides into said overlying relation when the said side flange slides are out of said overlying relatiom 2. A box forming machine according to claim 1 Wherein said plunger means comprises upper and lower box forming plungers, said upper plunger having a flat platen substantially of the score dimension of the blanks, and said lower plunger having a flat suction head, means to impart up and down strokes to said upper plunger, means for imparting up and down strokes to said lower plunger, said upper plunger in its down stroke being adapted to first clamp the blank between said platen and said suction head and then to continue in down stroke with the clamped blank and suction head so as to cause the marginal portions of the blank to engage said slides and bend upwardly to form side and end box flanges, means for applying suction to said suction head to hold the flanged blank in place, and control means to initiate the upstroke of the upper plunger prior to operation of said movement-imparting means.

3. A box forming machine according to claim 2 including means to adjust the lower position of said suc- 12 tion head to .vary theclearance between said headand said slides in the overlying position of the latter.

4. A box forming'machine ina ccordance with claim 1 in which said movement imparting means includes an actuating cam for one side 'slide, an actuating cam for the opposed side slide, an actuating cam for one end slide, and an actuating cam for the opposed end slide, said cams being timed to effect sequential operation of the slides in the order named.

5. A box forming machine comprising a stack of fiat paper blanks, means for feeding blanks from said stack to a box forming station, plunger means for pre-forming the blanks into box form, means for sequentially inwardly bending the side and end flanges of the preformed boxes to provide-definite folds therefor, means for directing an air blast against one side flange after bending thereof toinsure its beingin upright position, and means for similarly directing an air blast against-the opposed side flange after bending thereof, said air blasts References Cited in the file of this patent UNITED STATES PATENTS 101,354 Crosby Mar. 29, 1870 2,228,932 Thompson Jan. 14, 1941 2,743,651 Wilcox Q. May 1, 1956 2,844,077 Buhrke July 22,

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