US2821121A - Container forming machine - Google Patents

Description

Jan. 28, 1958 J. G. VERGOBBI 2, 1

CONTAINER FORMING MACHINE Filed Nov. 2 1954 3 Sheets-Sheet 1 INVENTOR.

k agcwquz Jan. 28, 1958 J. G. VERGOBBI CONTAINERv FORMING MACHINE 3 Sheets-Sheet 2 Filed NOV. 2. 1954 v INVENTOR. BY Q/OAn ATTORNEY Jam, 28,

-Filed NOV. 2, 1954 -J.G.VERGOBBI CONTAINER FORMING MACHINE 3 Sheets-Sheet 3 L gig .112 132 194 134 6% Qum- United States Patent CONTAINER FORMING MACHINE John G. Vergobbi, Quincy, Mass., assignor to Pneumatic Scale Corporation, Limited, Quincy, Mass 2 corporation of Massachusetts Application November 2, 1954, Serial No. 466,360

8 Claims. (CT. 93-8) This invention relates to a container forming machine.

In general the invention has for an object to provide a novel and efiicient container forming machine which among other uses may be embodied with advantage in a packaging machine for producing the inner liners for lined containers.

A further object of the invention is to improve upon the container forming machine forming the subject matter of my United States patent, No. 2,694,965, in respect to certain features thereof, as will be hereinafter pointed out.

With these general objects in view and such others as may hereinafter appear, the invention consists in the container forming machine and in the various structures, arrangements and combinations of parts hereinafter described and particularly defined in the claims at the end of this specification.

In the drawings illustrating the preferred embodiment of the invention:

Fig. l is a. side elevation of a container forming machine;

Fig. 2 is a plan view of a portion of the machine shown in Fig. 1;

Fig. 3 is a plan view detail, partly in cross section, of one of the bag opening and transferring members;

Fig. 4 is a detail view of a creasing mechanism for producing a creased line along the longitudinal side seam of a folded strip of container forming material; and

Fig- 5 is a perspective view of a partially formed lining bag produced by the presentmachine.

One feature of the present invention resides in the provision of novel and improved container opening mechanism in a container forming machine of the type shown in my United States patent above referred to.

Another feature of the present invention resides in the provision of a novel mechanism for effecting the folding of a side seam in predetermined direction with relation to the formation of an end closure of the container to insure most satisfactory folding operations incident to the formation of the end closure, as will be described.

Referring now to the drawings, the container forming machine illustrated in Fig. 1 may comprise the machine illustrated and described in my United States patent, No. 2,694,965, except as to details to be hereinafter pointed out, and as herein shown, represents a web of heat scalable bag forming material which may be withdrawn from a roll 12 by unwinding mechanism, indicated generally at 14, and in general in the formation of the bag the web is arranged to pass over the shaping mechanism comprising a generally V-shaped flared forming member 16 and between idle folding rolls 18, 20 arranged to fold the web longitudinally to present opposed upper and lower portions of the walls of the web in contiguous engagement. Thereafter, the folded strip is arranged to pass between cooperating sealing rollers 22, 24, one or both of which may be heated by any suitable heating. means, such as an electrical heating element, not shown.

In order to provide a vent opening in the bag and to. project a stream of air through said opening and into the foremost bag section which is about to be transferred' onto a mandrel, an air pipe 26 is arranged to extend vertically, as illustrated, between the side walls of the strip at a point adjacent the forming member 16 until it reaches a point midway between the upper and lower edges of the strip, and thereafter the pipe is extended horizontally and longitudinally of the strip between the side walls thereof. The air pipe 26 may be relatively small in diameter, as illustrated, in order to occupy a minimum space between the walls of the strip and may terminate at a point adjacent the endmost bag section. In order to accommodate the air pipe 26 between the strip during the forming and sealing operations, each roller 18, 20 may be provided with a grooved portion 28 arranged to straddle the pipe, and the sealing rollers 22, 24 are likewise provided with grooved portions 30 to leave an unsealed portion at the point Where the pipe passes between the walls of the strip. The coopera-ting heat sealing rollers 22, 24 are provided with cooperating sealing areas 23 for forming the longitudinal seal and with opposed sealing areas 25 for forming spaced transverse seals, the circumferential distance between the sealing areas 25 determining the spacing and length of each bag section, so that in operation there are formed a continuous longitudinal seal and successive transverse seals whereby to form a series of equally spaced bag sections.

The strip of bag forming material iscontinuously drawn through the shaping and sealing devices by a pair of driven feed rolls 32, 34 provided with correspondingly grooved portions 36 to straddle the air pipe 26 and to continue the vent opening in the transverse portion of the strip. The feed rolls 32, 34- are arranged to advance the strip continuously at a substantially constant rate, and when the endmost bag section is extended a pre determined distance beyond the feed rolls 32, 34, and while air is being projected between the bag walls through the air pipe 26 to facilitate opening of the bag, the opposed side walls at the forward end or mouth portion of the bag section are grasped and spread apart slightly by opposing suction members 38 of a reciprocal bag opening and transferring device indicated generally at 40, arranged to travel forwardly at the same rate as the strip during this portion of its cycle. After the bag walls have been spread apart slightly, as described, a reciprocating cutter, indicated generally at 42, is also arranged to be bodily moved forwardly at the same speed as the strip and operates to sever the endmost bag section from the strip, and simultaneously therewith or immediately thereafter, the air vent opening is sealed by heat sealing elements 44, 46 carried by and movable with the severing mechanism 42. The cut is preferably made along a line immediately to the rear of each transverse seal whereby the latter forms the end or bottom closure for the endmost bag section, and the severed portion adjacent thereto forms the opening for the mouth of the succeeding bag section, thus forming individual bags open at the forward end and completely sealed at the trailing end or bottom of the bag. The air pipe 26 may terminate at a point beyond the feed rolls 32, 34 and immediately in front of the severing mechanism 42 in its maximum retracted position. After severance of the bag section from the strip the speed of the bag opening and transferring mechanism 40 is increased and the mouth of the bag is spread apart further to permit the bag to be drawn over an expansible mandrel 48, the latter preferably forming one of a plurality thereof carried by an intermittently rotatable spider 50 of the carton forming machine. The reciprocal bag opening and transferring device 40 and the reciprocal cutting and sealing unit 42 are then quickly returned to their initial positions at an increased speed in time to open and sever a succeeding bag section of the continuously moving strip of connected bag sections.

In' general the machine thus far described comprises the machine forming the subject of my United States patent, No. 2,694,965, to which reference may be made for additional details of its structure and operation.

- cam operated reciprocating mechanism, indicated generally at 62, and which is fully illustrated and described in my copending application above referred to. The lower ;end of each shaft 54 is provided with an arm 64 fast thereon having a cam roll 66 for cooperation with a centrally disposed cam piece 68. The lower ends of the suction members 38 are provided with studs 70 .ro-

'tatably mounted in the arms 52, and in order to control the movement of the suction members to efl ect substantially lateral separation of the side walls of the bag,

during the rocking movement of the arms 52, each suction member is provided with a parallel linkage including arms 72, 74 and link 76, the arms 72, 74 being fast on the studs 70 and shafts 54 respectively. Suitable springs, not shown, may be provided to urge the suction units inwardly and to hold the cam rolls 66 against their cam piece 68.

As shown in Fig. l and in detail in Fig. 3, each suction -member 38 is provided with a plurality of suction openings 78 in communication with a vertical passageway 80 formed in the suction member, each suction opening being defined by a small tube 82 fixed in the suction :member'and extended through a rubber or like insert 84, the outer end of the tube being flush with the outer face of the rubber insert and provided with cutouts around the outer end thereof, as shown. The vertical passageway 80 may be connected by a nipple and a flexible tube 86 to the slide bracket 56 which is provided with a passageway operatively connected by a pipe to a suction chamber formed in a piston slidably mounted in the supporting shaft 58,'the latter having a slot in its :underside for passage of the connecting pipe during reciprocation of the slide bracket 56. The outer end of the piston may be connected by a pipe 88 leading to a cam operated valve 90 which may be connected by a pipe 92 to any usual or preferred source of suction.

When the strip of connected bag sections has been advanced a predetermined distance beyond the strip acl vancing rolls 32, 34 the mouth portion of the endmost 'bag section is spread apart slightly by the opposed suction members 38 of the bag opening and transferring mechanism 40 arranged to travel along with the strip, and during this time air is projected from the pipe 26 through the vent opening into the bag to facilitate separation of the side walls by the suction cups. It will be understood that in operation the suction members are spaced from the side walls of the mouth portion, and the suction 'effects separation of opposed walls of the mouth and causes them to be brought into engagement with the suction members, the air which is being blown between the side walls of the bag assisting such separation. The air to the pipe 26 may be controlled by a cam operated valve, indicated generally at 27, which may be connected to any usual or preferred source of compressed arr.

While the open mouth portion of the bag is thus supported by thesuction members 38 the severing mech- -August 10, 1948. bag opening and transferring mechanism 40 the mandrel :is expanded to form a rectangular bag having a project.-

anism 42, also arranged to travel along with the strip, is operated to sever the endmost bag section from the strip, and the heat sealing elements 44, 46 carried by the severing mechanism operate to seal the vent opening in the bag whereupon the suction members are spread apart during their advance to transfer the bag onto the expansible mandrel 48, the latter being in its collapsed form at this time.

From the description thus far it will be seen that in operation when the slide member 56 is in its fully retracted position the suction members 38 are disposed in spaced relation on opposite sides of the endmost bag section, and as the slide member starts forward the vacuum valve may be operated to efifect adherence of opposed side walls of the bag to the suction members. Thereafter, upon severance of a bag section from the strip by the cutting mechanism 42 the opposed suction members 38'are spread apart as the bag is advanced toward the expansible mandrel 48. At this time, when the bag is partially opened, provision is made for engaging the interior of the side walls adjacent the mouth portion of ,the bag for maintaining the bag material fiat in engagement with the suction members whereby to prevent kinking or buckling of the side walls being spread apart. As herein shown, this operation maybe accomplished by a pair of flat spring blades 94 mounted on arms 96 fast on the upper ends of vertical rods 98.

The rods 98 may be rotatably mounted in bearings 100 attached to and movable with the suction members 38, as shown, and the lower ends of the rods 98 may be provided with similar arms 162 having cam rolls 104 arranged to cooperate with opposed elongated stationary cam pieces 105, 106 supported on uprights 108 mounted in brackets 109 attached to the machine frame, as shown. A spring 110 is arranged to rock the flat blades 94 in wardly into engagement with the inner surfaces of the side walls of the partially opened bag and to resiliently press the side walls against their respective suction members 38, the cam pieces 105, 106 operating to rock the spring blades outwardly.

In the operation of the machine, during continued advance of the suction members 38 they are spread apart 'further to fully open the mouth of the bag by engagement of the rollers 66 with the central cam piece 68, and the bag is transferred onto the mandrel 48, the opposed cam pieces 105, 106 being arranged to rock the spring blades 94 out of engagement with the side walls of the bag as the suction members approach the end of their stroke. Thereafter when the suction members 38 are in their fully extended position the suction is opened to the atmosphere by operation of the valve 90 to release the bag from the suction members, whereupon the latter are quickly returned to their initial retracted position in readiness to open and transfer the next succeeding bag section severed from the strip.

The expansible mandrels 48 shown in Fig. 2 may comprise the expansible mandrels illustrated and described in my United States patent, No. 2,446,798, issued In operation upon retraction of the ing side seam 112, a projecting bottom seam 114, and extended triangular tabs 116, as shown in Fig. 5. Thereafter, during the intermittent movement of the mandrel to the next station of operation the expanded bag is arranged to engage a stationary rail unit for folding the projecting side and bottom seams 112, 114 in a predetermined direction flat against the bag and for subsequently folding the triangular extended tabs inwardly, as fully illustrated and described in my United States patent, No. 2,446,798.

strip for fi reasing the side seam along the inner edge thereof. As herein shown, this operation may be effected by a rotary creasing member 118 in cooperation with a stationary guide or backing member 120 disposed intermediate the sealing rollers 22, 24 and the feed rollers 32, 34 as shown in Fig. 1. As illustrated in detail in Fig. 4, the guide member 120 may be secured to a bracket 122 attached to the machine frame and may comprise an angle piece having a curved .and inclined portion 124 for engaging and guiding the longitudinal seam of the strip onto the backing member 120 and into operative engagement with the creasing roll 118, the crease being preferably formed adjacent the inner edge of the seam. The creasing member 118 may be rotatably mounted on a stud 12d threadedly engaged in the end of an arm 12S pivotally mounted on a stud 130 carried by a bracket 132 attached to the underside .of the guide member 129. As shown in Fig. 4, the creasing member 118 is urged into engagement with the inner edge of the seam by a spring 134 connected between the arm 128 and a depending portion 136 of the bracket 132. An upward extension from the bracket 132 carries a stop screw 138 cooperating with a stop member 140 extended from the arm 128 for adjusting the creasing pressure against the seam, and a second stop screw 142 carried by a lateral extension from the bracket 132 is arranged to cooperate with the stop member 140 when the roller is manually rocked into an inoperative position for the purpose of initially inserting the leading end of the bag strip into the creasing mechanism. The creased seam subsequently passes between the feed rolls 32, 34 with the seam in its normally extended position, as shown. Thus, in operation when the fiat bag is subsequently transferred to the mandrel and expanded into rectangular form the longitudinally extended creased side seam will naturally bend in the precreased direction which is consistent with the subsequent folding operations performed during the movement of the mandrel to the next station of operation.

From the above description it will be seen that the present structure of container forming machine is prov vided with improved bag opening and transferring mechanism particularly adapted to handle relatively rigid or multiple ply bag material and wherein provision is made for assuring retention of the bag by the transferring mechanism during the transfer operation. It will also be seen that the present container forming machine is provided with mechanism for precreasing the longitudinal seam of the bag strip during the formation of the bag whereby to facilitate subsequent folding of the bag after being transferred to a mandrel and expanded into rectangular form.

While the preferred embodiment of the invention has been herein illustrated and described, it will be understood that the invention may be embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed 1s:

1. In a container forming machine, in combination, an expansible mandrel, means for supporting a fiat bag having an open mouth portion in alignment with said mandrel, means for opening and transferring the bag onto said mandrel including bag opening members engageable with the outer faces of opposed side walls of the flat bag adjacent the mouth portion, and means cooperating with said bag opening members and engageable with the inner faces of opposed side walls of the bag for maintaining the side walls flat against their respective bag opening members during the transfer operation, said cooperating means being engageable with said inner faces in gripping relation with said bag opening members to assure retention of the bag by the opening and transferring members during the transfer operation.

2. In a container forming machine, in combination, an expansible mandrel, means for supporting a fiat bag having an open mouth portion in alignment with said mandrel, means for opening and transferring the bag onto .said mandrel including a pair of suction members .engageable with the outer faces of opposed side walls of the flat bag adjacent the mouth portion to spread thes'ide Walls apart, means for moving said suction members to effect opening of the bag and for transferring the bag onto said mandrel, and means cooperating with said suction members and engageable with the inner faces of opposed side walls of the bag for maintaining the side walls fiat against their respective suction members during the transferring operation, said cooperating means being engageable with said inner faces in parallel and gripping relation with said suction members to assure retention of the bag by said suction members during the transferring operation.

3. A container forming machine of the character described having, in combination, a plurality of expansible mandrels, means for folding, sealing and severing a strip of bag forming material to form individual fiat bags having an open mouth portion, reciprocable means for opening and transferring successive fiat bags onto successive mandrels including a pair of suction members engageable with the outer faces of opposed side walls adjacent the mouth of the bag, means for operating said suction members to effect opening of the bag and transfer of the same onto a mandrel, and means cooperating with said suction members and engageable with the inner faces of opposed side walls in parallel and gripping relation with said suction members for maintaining said side walls fiat against their respective suction members whereby to assure retention of the side walls by the suction members during the transferring operation.

4. A container forming machine of the character described having, in combination, a plurality of expanzsible mandrels, means for folding, sealing and severing a strip of bag forming material to form individual flat bags, each having an open mouth portion and a sealed bottom portion provided with an air vent, reciprocable means for opening and transferring successive flat bags onto successive mandrels including a pair of suction members engageable with the outer faces of opposed side walls adjacent the mouth portion of the bag, means for operating said suction members to effect opening of the bag and transfer of the same onto a 'mandrel, means for directing a stream of air through said vent and between the side walls of the bag to facilitate separation thereof during the opening operation, means for thereafter closing said vent, and means cooperating with said suction members and engageable with the inner faces of opposed side walls in parallel and gripping relation with said suction members for maintaining the side walls flat against their respective suction members whereby to assure retention of the side walls by the suction members during the transferring operation.

5. A c ntainer forming machine of the character described having, in combination, a plurality of expansible mandrels, means for folding, sealing and severing a strip of bag forming material to form individual fiat bags having an open mouth portion and provided with a longitudinal face to face side seam and a similar bottom seam, means for opening and transferring successive flat bags onto successive mandrels, said mandrels being adapted to be expanded to form a rectangular bag with the face to face seams extended from the body of the bag, and means for forming a crease line along the inner edge of said longitudinally extended seam during the formation of the bag strip whereby to cause said seam to bend in a predetermined direction against the body of the bag when the same is subsequently expanded into rectangular form, said creasing means including a stationary backing member and a freely rotatable creasing roller cooperating with said stationary backing member.

6. In a container forming machine, in combination, a plurality of expansible mandrels, means for folding, sealing and severing a strip of bag forming material to form individual fiat bags having an open mouth portion and provided with a longitudinal face to face side seam and a similar bottom seam, reciprocable means for opening and transferring successive fiat bags onto successive mandrels including a pair of suction members engageable with the outer faces of opposed side walls adjacent the mouth of the bag, means for operating said suction memofthe bag for maintaining the side walls flat against their respective suction members, and means for forming a crease line along the inner edge of said longitudinally extended seam during the formation of the bag strip whereby to cause said seam to bend in a predetermined direc tion against the body of the bag when same is subsequently expanded into rectangular form, said means co operating with said suction members comprising a pair of rockingly mounted resilient blades engageable in parallel and gripping relation With said suction members, and said creasing means including a stationary backing member, and a freely rotatable creasing roller cooperating with said backing member.

7. A container forming machine of the character described having, in combination, a plurality of expansible mandrels, means for folding, sealing and severing a strip of bag forming material to form individual fiat bags having an open mouth portion, reciprocable means for opening and transferring successive flat bags onto successive mandrels including a pair of suction members engageable with the outer faces of opposed side walls adjacent the mouth of the bag, means for operating said suction members to effect opening of the bag and transfer of the same onto a mandrel, and means cooperating with said suction members and engageable with the inner faces of opposed side walls for maintaining said side walls flat against their respective suction members whereby to assure retentionof the side walls by the suction members during the transferring operation, said means cooperating with said suction members comprising a pair of rockingly mounted resilient blades carried by said reciproca'ble bag opening and transferring means, and means for operating said resilient blades to effect rocking of the same into engagement with the inner faces of the side walls after the mouth of the bag has been'partially opened during the transferring operation and for rocking the blades out of engagement with the side walls when the transferring means approaches the end of its transfer stroke. 7

8. A container forming machine of the character described having, in combination, a plurality of expansible mandrels, means for folding, sealing and severing a strip of bag forming material to form individual fiat bags having an open mouth portion, reciprocable means for open ing and transferring successive fiat bags onto successive mandrels including a pair of suction members engageable with the outer faces of opposed side walls adjacent the mouth of the bag, means for operating said suction members to effect opening of the bag and transfer of the same onto a mandrel, and means cooperating with said suction members and engageable With the inner faces of opposed side walls for maintaining said side walls flat against their respective suction members whereby to assure retention of the side walls by the suction members during the transferring operation, said means cooperating with said suction members comprising a pair'of rockingly mounted resilient blades carried by said reciprocable bag opening and transferring means, and means for operating said resilient blades to effect rocking of the same into engagement with the inner faces of the side walls after the mouth of the bag has been partially opened during the transferring operation and for rocking the blades out of engagement with the side walls when the transferring means approaches the end of its transfer stroke, said suction members comprising vertically elongated and rockingly mounted members having a plurality of suction openings, said resilient blades preventing buckling of the side walls relative to the suction openings during the transferring operation.

References Cited in the file of this patent UNITED STATES PATENTS 1,298,586 Sidebotham Mar. 25, 1919 2,689,073 Twigg Sept. 14, 1954 2,694,965 Vergobbi Nov. 23, 1954

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