US3023680A

US3023680A - Carton folding machines

Info

Publication number: US3023680A
Application number: US24301A
Authority: US
Inventors: Bayley Frederick James
Original assignee: Pembroke Carton and Printing Co Ltd
Current assignee: Pembroke Carton and Printing Co Ltd
Priority date: 1960-02-19
Filing date: 1960-04-25
Publication date: 1962-03-06
Anticipated expiration: 1979-03-06
Also published as: DE1144094B; GB928447A

Description

March 6, 1962 F. J. BAYLEY CARTON FOLDING MACHINES 3 Sheets-Sheet 1 Filed April 25, 1960 40M? I l March 6, 1962 F. J. BAYLEY 3,023,680

CARTON FOLDING MACHINES Filed April 25, 1960 5 Sheets-Sheet 2 V1. i? j? March 6, 1962 F. J. BAYLEY 3,023,680

CARTON FOLDING MACHINES Filed April 25, 1960 5 Sheets-Sheet 5 M, @ra/M TTH/VEVS United States Patent O 3,023,680 CARTON FOLDING MACHINES Frederick .lames Bayley, 'I'hundersley, England, assigner to Pembroke Carton & Printing Co., Ltd., Basildon, England, a British company Filed Apr. 25, 1960, Ser. No. 24,301 Claims priority, application Great Britain Feb. 19, 1960 13 Claims. (Cl. 93-51) The present invention relates to carton folding machines for converting carton blanks into carton form, and is concerned with machines of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides `of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish form the carton in the die after the plunger has been withdrawn from the partly formed carton.

A machine of ythe kind just described is suitable for folding cartons generally referred to as roll-over end or side lock cartons. With cartons of this kind at least one side or end forming portion of the carton blank has an extended or roll-over panel at its top edge which is folded over into the carton, into locking engagement with the bottom panel of the carton.

In order to fold the roll-over panel, the plunger must rst be withdrawn from the carton and the carton supported in the die aperture for the final folding operation. After the final folding operation the carton is then ejected through the bottom die by the next following carton being formed.

The object of the present invention is to provide for folding lidded cartons a carton folding machine of the kind described above having a die wall defining member which is movable between an operative position in which it defines with fixed wall parts of the die, the die aperture and an open position away from said fixed die parts, the movable die wall dening member being movable to its open position to expand at least the lower end part of the die to release a nish `formed carton in the die aperture for ejection from the die by the next following carton.

A further object of the invention is to provide a movable part in the die for engaging beneath the partly formed carton to support it in the die aperture ready for r the ynal folding operation, the supporting part being movable lto withdraw from beneath the iinished formed carton when the die wall defining member is moved to its open position.

Preferably two of said movable supporting parts are provided one on the xed wall parts of the die and the other on the movable wall defining member.

A further object of the invention is to control the movev ment of the movable wall defining member in dependence upon the movement of the plunger whereby the various holding operations and the eieetion are performed in proper sequence as the plunger is reciprocated.

The manner in which these and other objects of the invention may be met in accordance with the invention will now be described merely by way of example with reference to the accompanying drawings in which:

FIG. l is a side elevation of a carton erecting machine in accordance with the invention,

FIG. 2 is a front view of the machine with the die in section,

FIG. 3 is a side view in cross-section of the die,

FIG. 4 is an underneath plan view of the machine, and

"ice

FIG. 5 shows a carton blank erectable in the machine.

'I'he machine comprises a frame 10 having a pair of side frame members 11 and a cross-piece 12 at its upper end.

The members 11 have vertical slots 13 bounded on each side by guides 14 between, which is slidably mounted a reciprocable assembly 15 comprising a plunger 16. The plunger 16, which is generally of rectangular section, is carried at ythe lower end of an arm 17 depending from a cross-head 18, the arm 17 and the cross-head 18 forming part of the assembly 15.

The cross-head 1S slides in the slots 13, the two ends of the cross-head having depending stop arms 19 received one between each pair of guides 14 and also constituting parts of the assembly 15.

In the lowermost position of the plunger 16, which position the plunger reaches at the end of its advancing stroke, the lower ends of the stop arms 19 engage rubber buffers 20 to limit the stroke of the assembly 15.

In the uppermost position of the plunger 16 the crosspiece 18 engages rubber buffers 21.

Mounted on the cross-piece 12 is a double acting pneumatic motor 22 the piston rod 23 of which is conneoted with the assembly 15 as at 24. When the motor is operated the assembly 15 is reciprocated vertically down and up to complete a single carton forming operation as will later appear.

The motor 22 may be controlled by means of a control circuit as described in co-pending application Serial No. 24,490, filed April 25, 1960.

The plunger 16 is movable into and out of a correspondingly shaped die generally indicated at 25. The die comprises a -rear wall 26, a front wall 27 and a pair of side walls 28. The die walls bound the die aperture which receives the plunger block with clearance.

The rear wall 26 and the side walls 2S are constituted by fixed die parts mounted on the frame 10. The fron-t die wall 27 is defined by a member 3? (see FIG. 3) which is hinged transversely towards its upper edge on a hinged rod 31 journalled in the side frame members 11 as at 32 (see FIG. 1).

Springs 33 connected between the member 30 and the rear wall part of the die urge the member into its vertical position in which the die wall 27 is located for a carton forming operation abutting the fixed die parts defining the die side walls 28. The operation of the movable member '30 will hereinafter appear.

Before the motor 22 is operated to reciprocate the assembly 15, a carton blank as shown in FIG. 5 is slid forward across the surface of a feed-in tray 34 to a location over the die aperture in which it is supported on the upper surfaces 35 of the die.

The carton blank shown in FIG. 5 has a roll-over end lock at each end and comprises a bottom panel 36, which coincides substantially in shape and extent with the bottom face 37 of the plunger 16, front and rear

side forming portions

38 and 39 connected along score lines to the long sides of the bottom panel 36, and end wall forming portions 40 connected along score lines to the short sides of the bottom panel.

The front and rear portions 3S, 39 have at their side edges a pair of laterally extending retaining aps 41, connected thereto along score lines, and the end portions 40 have extended or roll-over panels 42 with tongues 43 to engage in slots 44 in the bottom panel. The rear portion 39 has in addition a lid forming panel 44 connected along a score line at its top edge, the panel 44 being formed with tuck-in flaps 45 at its side edges and a tuck-in ilap 46 at its front edge.

To erect the carton from the blank, in the sequence which is adopted by the machine as Will later appear, the

Vback of the die.

aps 41 are bent upwardly at right angles to the front and

rear portions

38, 39, and the front and rear portions are then upfolded through 90 so that the aps 41 extend across the ends of the carton. The end portions 4i? are then upfolded so as to lie against the flaps 41 and the roll-over panels are folded' in to the carton to lie against the other side of the aps 1, the tongues 43 being engaged in the slots 44. The portions 40 and the panels 42 then retain the aps `41 and hold the front and

rear portions

38 and 39 erect.

The blank is of a width which ts between guide rails 47 extending along opposite sides of the tray 34 and is slid in over the die until the top edge of the front wall forming portion 3S cornes up against a stop wall 4S at the Further positioning stops 49 are provided to position the blank laterally, these engaging the edges of the flaps 41.

The various stops position the blank with its bottom panel 36 squarely over the die aperture.

As the plunger 16 is urged downwardly by the motor it engages the bottom panel 36 and forces the blank into the die.

The flaps 41 arerst folded up by the die shoulders 50 and then the front and

rear portions

38, 39 by the shoulders 51 which are below the level of the shoulders 50. The end portions 40 are then folded up by the shoulders 52 of the die which are below Vthe level of the shoulders 51. The carton is now partially erected with its sides and ends lying against the sides and ends of the plunger, the plunger being within the partially formed carton.

The lower edge of the die wall 26 is on a level with a ledge 53,0n the member 30 which ledge lies in the path of movement of the bottom panel 36 through the die when the member 30 is in its vertical position.

As clearly shown in FIG. 4, the ledge 53 is formed by a part 54 of the member 30 which penetrates between the die side walls 28 at the lower end of the die aperture when the member 30 is vertical.

Housed in a recess 55 immediately beneath the lower edge of the die wall 26 is a Vlever 56 pivoted on a vertical pivot 57 intermediate its ends and to one side of the die aperture. The lever 56 has one lever arm part 58 which extends across the lower end of the die aperture and a coiled spring 60 engaged between the rear wall of the recess 55 and the other lever armV 59 of the lever urges the part 58 from a projected position in which it forms a ledge, corresponding with the Vledge 53, along the lower edge of the die wall 26, -to a retracted position within the recess. The front edge of the part 58 is protiled as shown in FIG. 4 to limit the swinging movement required to retract it into the recess.

In its projected position the part 58 lies in the path of movement of the bottom panel 36 of the blank through the die. Y v

A push rod 61, pivoted to the lever arm 59, extends forwardly into abutting relation with the member 30, when the member 30 is in its vertical position, to hold the part 58 in its projected position as described above. The Vpush rod 61 slides in a xed support 63 intermediate its ends.

Attached to a depending part of the member 30, below the level of the bottom of the die aperture, is a transverse spindle 64, the ends of which pass through slots 65 in 'the side frame members 11, and carry rollers 66.

The rollers 66 co-operate with cams 67 mounted on the depending arms 19 to swing the member 30 about its hinge 32 away from the fixed die parts defining the die side walls 28.

As the plunger block 16 continues to descend through the die with the partially formed carton thereabout the cams 67 engage the rollers 66 and swing the member 30 as just described. y Y

Movement of the member '30 permits the springs 60 to retract the part 58.

The stroke of the plunger is just sufficient to carry the bottom panel of the partially formed carton to the level of the lower end of the die aperture.

Referring to FIG. 3, the die wall 26 is undercut as at 67 to form a downwardly facing lip 68 which is spaced from the lower end of the die aperture kby a little more than the height of the front wall portion 38 of the carton. In a similar way the die Wall 27 is recessed as at 69 to form a downwardly facing lip 70 which is spaced from the lower end of the die aperture by a little more than the height h of the front edge of the tuck-in ap 46 on the lid panel of the carton.

In this connection it will be understood that as so far erected the tuck-in

flaps

45, 46 have remained flat in the plane of the lid panel 44 andthe lid panel has remained upstanding in the plane of the rear wall portion 39 of the carton.

The tuck-in aps 45 to each side of the lid panel are accommodated in vertical slots 71 in the die side walls 28 and side downwardly through these slots as the carton blank is moved through the die.

When the plunger block reaches the end of its advancing stroke an upper edge part of the front wall portion 38 engages under the lip 68 and the front edge of the tuck-in flap 46 engages under the lip 70. As far as the wall portion 38 is concerned this occurs because the` portion tends to spring away from the plunger when in its upfolded position and accordingly bows itself suiciently on reaching the undercut 67 to engage an intermediate part of its upper edge beneath the lip 68.

The lid panel 44 is bracedby the tuck-in Vaps 45 engaged in the slots 71 to bow outwardly, and suiiicient clearance is left between the plunger 16 and the wall 27 to allow the wall portion 39 of the carton to spring away from the plunger to carry an intermediate part of the front edge of the tuck-in flap 46 beneath the lip 70 despite the fact that the member 30 is now swung out of its vertical position.

When the plunger block commences to withdraw the partially formed carton is retained by the

lips

68 and 70 which accordingly strip the partially formed carton oft the plunger as the plunger moves upwardly towards its starting position.

During the withdrawal stroke of the plunger the cams 67 run off the rollers 66 and the springs 33 return the member 30 to its vertical position in which the ledge 53 engages beneath the bottom panel 36 of the carton along its side edge with the front wall portion 38.

The member 30 in moving back to its vertical position operates the push rod 61 to project the part 58 to engage beneath the bottom panel 36 along its side edge with the rear wall portion 39.

The partially formed carton is now supported in the die aperture and the final folding operation of the rollover panels 42 is ready to be undertaken. At the present time the panels 42 are upstanding on the end portions 40 at against the die walls 28.

Mounted on spindles 72 and in recesses 73 in the die walls 2S are fingers 74.

By rotating the spindles '72, the lingers 74 may be Vswung round from the retracted position, as shown in chain-dotted line in FIG. 2, to engage and fold inwardly the roll-over panels. The tips of the ngers engage the roll-over panels adjacent the tongues 43 along the line of the side edge of the panels from which these tongues project. The ngers, as they are swung round, carry the tongues 43 into engagement with the bottom panel 36 and then across the bottom panel which deects slightly to allow the passage of Vthe tongues until iinally the tongues snap into the slots 44. K

The spindles 72 are journalled in the die parts and eX- tend from the die to the back of the machine where they carry sprocket wheels 75 which are driven one each by chains 77 from a further pairof sprocket wheels 76. Fast with each sprocket wheel 76 is an arm 78 having a slot 79.

Each arm 19 carries, above its cam 67, a plate 8l) having a pair of spaced upstanding lugs 81 in which are xed rearwardly extending pins 82, and the rear ends of the pins 82 engaging in the slots 79 and making sliding pin-and-slot connections therewith.

The arrangement is such that movement of the assembly 15, and hence the arms 19, to withdraw the plunger from the die angularly adjusts the arms 78, through pinand-

slot connections

79, 82, to rotate the sprocket wheels 76 and hence the sprocket wheels 75 to rotate the spindles 72 to swing the fingers 74 from their retracted position within the recesses 73 to their operative position fully folding the roll-over panels 40 of the carton supported in the die aperture on the part 54 and the part 58.

The gearing between the

sprocket wheels

75 and 76 is selected so that the fingers 74 reach their final position fully folding the roll-over panels at the instant that the plunger reaches the end of its withdrawal stroke.

The machine is now ready to erect the next carton blank, hereinafter referred to as the second carton blank, which is slid into position over the die aperture as before.

As the plunger is again urged downwardly, the fingers 74 commence to swing back to their retracted position. After about one half of the advancing stroke of the plunger has been completed, the cams 67 engage the rollers 66 and swing the member 30 out of its vertical position thus withdrawing the part 54 from beneath the bottom panel of the now finish-formed carton in the bottom of the die aperture. At the same time the spring 60 withdraws the part 58 from beneath the bottom panel of the finish-formed carton, the part 58 being retracted into the recess 55 as previously explained.

The finish-formed carton is thus freed for ejection through the bottom of the die aperture and the carton is ejected by the second carton the bottom panel of which, backed by the plunger block, cornes up against the top edge of the front and side walls of the finished carton to push it out of the die as the second partially erected carton is moved by the plunger block into position with the top edge of its front wall portion engaging under the lip 68 and the front edge of its tuck-in flap 46 engaging under the lip 70. Y

At this time, the lingers 74 have been moved back to their fully retracted position.V

On the subsequent withdrawal stroke of the plunger the second, now partially formed carton is stripped from the plunger block, the member 30 returns to its vertical position thus engaging the

parts

54 and 58 under the bottom panel of the carton and the fingers 74 are swung round to fold the roll-over panels all as previously described.

It is to be noted that the length of the plunger stroke is governed by the requirement that the ngers 74 shall be retracted within the recesses 73 before the bottom panel of a carton being formed in the machine reaches the level of the top of the finger recesses assuming that the fingers just clear the tops of the recesses.

This is because the angular 'position of the fingers is directly dependent on the position of the plunger.

When the plunger reaches the end of its advancing stroke and commences to withdraw, the

parts

54 and 58 are not in position to support the partially formed carton. The carton is however drawn up against the

lips

68 and 70 by the plunger block and is prevented from falling out of the bottom of the die. The side walls 28 of the die also grip the roll-over panels which ex outwardly against the side walls 2S and assist in preventing the partially formed carton from falling out.

As soon as the cams 67 clear the rollers 66 the

parts

54 and 58 move in under the carton and this action takes place as the plunger block leaves the mouth of the carton whereafter the carton cannot then fall out in any case.

When the carton is finally ejected by the next carton, the bottom panel of the next carton and the plunger block are able to move down past vthe lid panel of the carton 6 to be ejected by virtue of the recess 69 which accommodates the lid panel out of the path of the bottom panel of the next carton.

It is to be noted that the various operations of the moving parts of the machine are timed in the required sequence directly or indirectly by the movement of the plunger.

Thus the member 30 is movable directly in dependence upon the position of the plunger and likewise the angular position occupied by the lingers 74 at any instant depends directly on the position of the plunger.

The part 58 is moved in dependence on the movement of the member 30 and therefore indirectly in dependence upon the movement of the plunger.

I claim:

l. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish-form the carton in the die after the plunger has been Withdrawn from the partly formed carton; a movable wall member which forms a wall section of the die which extends completely across one side of the die aperture, said wall member being movable between an operative position in which it denes, with xed Wall sections of the die, the die aperture, and an open position away from said lixed wall sections thereby to expand at least the lower end part of the die, and means for moving said wall member to its open position to release, for ejection through the bottom of the die by the next following carton being formed, a carton linish-formed in the die aperture.

2. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a movable wall member which forms a wall section of the die which extends completely across one side of the die aperture, said wall member being movable between an operative position in which it defines, with xed wall sections of the die, the die aperture, and an open position away from said fixed wall sections thereby to expand at least the lower end part of the die, a movable part in the die for engaging beneath the partly formed carton to support the partly formed carton in the die aperture, said movable part being operatively connected with said wall member to move to withdraw from beneath a carton finish-formed in the die aperture when said wall member is moved to its open position, and means for moving said wall member to its open position to release for ejection by the next following carton being formed a carton finish formed in the die aperture.

3. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, vand means in the die for folding at least one further panel of the blank thereby to finish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a movable wall member which forms a wall section of the die which extends completely across one side of the die aperture, saidwall member being movable between an operative position in which it defines, with fixed lWall sections of the die, the die aperture, and an open position away from said fixed -wall sections thereby to expand at least the lower end part of the die, a movable part in the die for engaging beneath the partly formed carton to support the partly formed carton in the die aperture, said movable part being xed to said Wall member to move to Withdraw from beneath a carton finishformed in the die aperture when the wall member is moved to its open position, and means for moving said die-wall-detining member to its open position to release for ejection by the next following carton being formed a carton finish formed in the die aperture.

4. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a Withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of `a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby lto finish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a movable wall member which forms a wall section of the die which extends completely across one side of the die aperture, said wall member being movable between an operative position in which it denes, with fixed wall sections of the die, the die aperture, and an open position away from said fixed wall sections thereby to expand at least the lower end part of the die, and means operab'ly interconnecting said wall member with said plunger to move said wall member to its open position when the plunger is moved through a latter part vof its advancing stroke to release for ejection by the next following carton on the plunger the carton finish formed in the die aperture.

5. In a carton folding machine of the kind comprising a generally rectangular Isectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die yby the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a movable Wall member which forms a wall section of the die which extends completely across one side of the die aperture, said wall member being movable between an operative position in which it defines, with fixed wall sections of the die, the die aperture, and an open position away lfrom said fixed wall sections thereby to expand at least the lower end part of the die, and cooperating cam and cam follower means one on the plunger and the other on said wall member for moving said wall member to its open position when the plunger is moved through a latter part of its advancing stroke to release for ejection by the next following carton on the plunger the carton finish formed in the die aperture.

6. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a Withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a movable vwall member which forms a wall section of the die which extends completely across one side of the die aperture, said Wall member being movable between an operative position in which it defines, with fixed wall sections of the die, the die aperture, `and an open position away from said fixed wall sections thereby to expand at least the lower end part of the die, spring means connected with said Wall member and urging the member to its operative position, and co-operating cam and cam follower means one on the plunger and the other on said wall member for moving said wall member to its open position against the action of said spring means when the plunger is moved through a latter part of its advancing stroke to release for ejection by the next following carton on the plunger the carton finish formed in the die aperture. Y

7. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish-form the carton inthe die after the plunger has been withdrawn from the partly formed carton; a movable wall member which forms a wall section of the die which extends completely across one side of the die aperture, said wall member being movable between an operative position in which it defines, with xed wall sections of the die, the die aperture, and an open position away from said fixed wall sections thereby to expand at least the lower end part of the die, amovable part pivoted on one of said fixed wall sections and movable from a retracted position to a projected position to engage beneath the partly formed carton to support the partly formed carton in the die aperture, spring means urging said movable part to its retracted position to withdraw said part from beneath a carton finish-formed in the die aperture, means engaged by said wall member when the wall member is in its operative position to hold said movable part in its projected position against the action of said spring means, and means for moving said wall member to its open position to release for ejection by the next following carton being formed a carton finish formed in the die aperture.

8. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a movable wall member which forms a Wall Section of the die which extends completely across one side of the die aperture, said wall member being movable between an operative position in which it defines, With xed wall sections of the die, the die aperture, and an open position away from said fixed wall sections thereby to expand at least the lower end part of the die, a movable part pivoted on one of said xed wall sections of the die and movable fromy a retracted position to a projected position to engage beneath the partly formed carton to support the partly formed carton in the die aperture, spring means urging said movable part to its retracted position to withdraw said part from beneath a carton finish-formed in the die aperture, a push rod supported from one of said yfixed wall sections and operable by said wall member when it is moved to its operative position to move said movable part to its projected position, spring means connected with said wall member and urging the wall member to its operative position, and means for moving said wall member to its open position to release for ejection by the next following carton being formed a carton huish formed in the die aperture.

9. In a carton folding machine of the kind comprising a generally rectangular sectioned plunger reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to nish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a movable wall member which forms a wall section of the die which extends completely across one side of the die aperture, said wall member being movable between an operative position in which it defines, with fixed wall sections of the die, the die aperture, and an open position away from said xed wall sections thereby to expand at least the lower end part of the die, a movable part pivoted on one of said xed wall sections and movable from a retracted position to a projected position to engage beneath the partly formed carton to support the partly formed carton in the die aperture, spring means urging said movable part to its retracted position to Withdraw said part from beneath a carton finish-formed in the die aperture, a push rod supported from one of said xed wall sections and operable by said wall member when it is moved to its operative position to move said movable part to its projected position, spring means connected with said wall member and urging said wall member to its operative position, and means operatively interconnecting said wall member with said plunger to move said wall member to its open position when the plunger is moved through the latter part of its advancing stroke to release for ejection by the next following carton on the plunger the carton nish formed in the die aperture.

10. In a carton folding machine of the kind comprising a generally rectangular sectional plunger vertically reciprocable through an advancing stroke and a withdrawal stroke, a die having an aperture of a size to receive the plunger, the plunger being movable into the die on its advancing stroke to upfold in the die against the sides of the plunger the side forming panels of a carton blank forced into the die by the plunger thereby partly to form the carton, and means in the die for folding at least one further panel of the blank thereby to finish-form the carton in the die after the plunger has been withdrawn from the partly formed carton; a Wall member which forms a wall section of the die which extends completely across one side of the die aperture, said wall member being horizontally hinged towards its upper end so as to be movable between a vertical position in which it deiines, with fixed wall sections of the die, the die aperture, and an open position in which the wall member is swung away from said xed wall parts thereby to expand the lower end part of the die, and means for moving said wall member to its open position to release, for ejection by the next following carton being formed, a carton nish-formed in the bottom of the die aperture.

1l. A carton folding machine as claimed in claim l0, wherein said wall member carries at its lower edge a part to engage beneath a partly formed carton in the bottom of the die aperture to support the carton during the nish-forming operation, said part being withdrawable from beneath the huish-formed carton by movement of said Wall member to its open position.

12. A carton folding machine as claimed in claim 10, wherein said Wall member is undercut to form a downwardly facing lip to engage over an upstanding panel of the partly formed carton to retain the partly formed carton in the bottom of the die when the plunger is withdrawn from the die.-

13. A carton folding machine as claimed in claim 12, wherein the xed wall section of the die opposite said wall member is also undercut to form a downwardly facing lip to engage over a further upstanding panel of the partly formed carton to retain the partly formed carton in the bottom of the die aperture when the plunger is withdrawn from the die.

References Cited in the iile of this patent UNITED STATES PATENTS 2,819,660 Johnson Ian. 14, 1958 2,848,926 Gachwind et al. Aug. 26, 1958 2,921,506 Johnson Jan. 19, 1960