US3632250A

US3632250A - Apparatus for forming articles from thermoplastic sheet material

Info

Publication number: US3632250A
Application number: US13631A
Authority: US
Inventors: Gerald A Snow
Original assignee: UNITED IND SYNDICATE
Current assignee: United Industrial Syndicate Inc; UNITED IND SYNDICATE
Priority date: 1970-02-24
Filing date: 1970-02-24
Publication date: 1972-01-04
Anticipated expiration: 1989-01-04

Abstract

Apparatus is disclosed in which equal lengths of sheet material are advanced step by step through an article-forming station and one or more subsequent stations such as printing and blanking and stacking stations. Means are provided that establish a positive but adjustable step length with a timer-controlled dwell and a positive lock against movement of the material during a dwell. Each subsequent station is provided with means enabling its coacting members to be positioned lengthwise as required by the step length being used. In addition, the positions of the coacting members at the printing station are adjustable transversely as is the distance between the margin gripping chains of the material-advancing means.

Description

United States Patent [72] Inventor Gerald A. Snow Cumberland Foreside, Malne [21] Appl. No. 13,631 [22] Filed Feb. 24, 1970 [45] Patented Jan. 4, 1972 [73] Assignee United Industrial Syndicate, Inc.

Portland, Maine [54] APPARATUS FOR FORMING ARTICLES FROM THERMOPLASTIC SHEET MATERIAL 11 Claims, 22 Drawing Figs. [52] 425/155, 264/165, 425/290, 425/301, 425/307 [51] Int. Cl 1129c 17/02 [50] Field Search... 18/4 8,4P, 5 A, 19 R, 19 F, 19 P; 264/153, 165, 132

[56] References Cited UNITED STATES PATENTS 3,105,270 10/1963 Fibish 18/19P Primary Examiner-Robert L. Spicer, Jr. AnameyAbbott Spear ABSTRACT: Apparatus is disclosed in which equal lengths of sheet material are advanced step by step through an articleforming station and one or more subsequent stations such as printing and blanking and stacking stations. Means are provided that establish a positive but adjustable step length with a timer-controlled dwell and a positive lock against movement of the material during a dwell. Each subsequent station is provided with means enabling its coacting members to be positioned lengthwise as required by the step length being used. In addition, the positions of the coacting members at the printing station are adjustable transversely as is the distance between the margin gripping chains of the material-advancing means.

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SHEET 13UF 16 I'awezzibr PATENTEU JAN 4 I972 ZHEET lUBF 16 lzwezaiow III/II Getaid 03.15220 APPARATUS FOR FORMING ARTICLES FROM THERMOPLASTIC SHEET MATERIAL The present invention relates to apparatus for use in forming articles from a length of a fltermoplastic sheet material.

In the production of articles from thermoplastic sheet material, apparatus of the type disclosed in my copending application, Ser. No. 653,886, filed July I7, 1967, now US. Pat. No. 3,504,074, has proved effective. In such apparatus, the sheet material is advanced by steps, first through a heating station and then through a forming station and one or more subsequent stations, printing, clamping, and punching and blanking stations, for example. A dwell between steps is controlled by timing means ensuring a sufiicient between-step interval for the various operations to be performed and during each dwell, the sheet material is locked against movement.

One problem presented by such apparatus is that with article-forming molds appropriate for a particular article, the length of a step of the conveying means may be too long or too short, material waste resulting in the case of the former and inability to accept the corresponding dimension of the articles being the controlling factor in the case of the latter. In addition, the use of sheet material that is wider than necessary results in waste unless the width of the conveying means can be adjusted appropriately to ensure the marginal engagement of a narrower sheet material.

The general objective of the present invention is, accordingly, to provide a step-by-step sheet-material conveying mechanism in which the step length is adjustable without interference with the locking of the sheet material against movement during the dwells thereby to enable the step length to be adjusted as required by the dimension of the articles that extends lengthwise of the sheet material. Lengthwise adjustments of the positions of the coacting members at any subsequent station are also provided.

A particular objective of the present invention is to provide means by which the length of a step of the conveying means may be quickly and accurately adjusted to meet the corresponding dimensions of the articles to be formed at the forming station. Such means comprise a rotatable member drivingly connected to the conveying means and provided with a circular series of arcuately spaced seats. Seat-entering index and locking pins are employed, the index pin being carried by an actuator having its pivot axis concentric with the axis of the rotatable member and reciprocated by power operated means between reset and step-ending positions determined by stops. One stop is adjustable in a manner enabling the travel of the actuator to be increased or decreased. At the end of a step, the index pin is withdrawn from a seat and the locking pin inserted in a seat, while during a step, their positions are reversed. The control circuit by which the alternate steps and dwells are provided includes limit switches operable in response to movements of the actuator, one limit switch for each of the positions and the position of one switch being adjustable as required by the stop spacing.

Another objective of the invention is to provide means enabling the adjustments of the position of the adjustable stop and switch to be effected quickly and easily in increments determined by the seat spacing, an objective attained with a support, desirably but not necessarily common to both the adjustable stop and the adjustable switch, having an arcuate series of switch attachment sites, the series being concentric with the series of seats, each attachment site being radially aligned with a seat during a dwell.

Another objective of the invention is to provide a printing station having one or more printing units, each having one or more transversely spaced printers and their article supports, each unit being movable lengthwise of the apparatus and each printer and its article support being adjustable transversely of the sheet material.

Yet another objective of the invention is to provide for lengthwise movements of the coacting members at such other stations as punching, clamping, blanking and stacking stations to ensure their correct engagement with the articles.

A further objective of the invention is to provide means by which the spacing between the supporting and hold down chains that grip the margins of the material may be varied.

In the accompanying drawings, there is shown an embodiment of the invention illustrative of these and other of its objectives, novel features, and advantages.

In the drawings:

FIG. I is a side view of the apparatus, broken to foreshorten the drawing;

FIG. 2 is a side view, on an increased scale of the index station;

FIG. 3 is a section, on a further increase in scale, taken approximately along the indicated lines 3-3 of FIG. 2 and showing the index pin;

FIG. 4 is a like section taken approximately along the indicated lines 4-4 of FIG. 2 and showing the locking pin;

FIG. 5 is a section taken approximately along the indicated lines 55 of FIG. 2;

FIG. 6 is a plan view of one side of the chain supports at the infeed end of the conveying means;

FIG. 7 is a side view thereof;

FIG. 8 is a section taken approximately along the indicated lines 88 of FIG. 7;

FIG. 9 is a section through the forming station, on an increased scale, taken approximately along the indicated lines 9--9 of FIG. I;

FIG. 10 is a fragmentary side view of the forming station, on an increased scale, showing the detachable molds;

FIG. II is a view of the molds as seen from the infeed end of the forming station;

FIG. I2 is a side view of the printing station showing the supporting structure of the two printing units;

FIG. I3 is a section taken approximately along the indicated lines I3- 13 of FIG. 14 showing the means enabling the bases to be adjusted lengthwise of the apparatus and the adjustable supports that are to underlie the articles while they are being printed;

FIG. 14 is an end view of the printing station;

FIG. 15 is a side view, on an increased scale of one of the printers with the roll inking means omitted;

FIG. 16 is a top view thereof;

FIG. 17 is an end view of the printer;

FIG. 18 is a view of the clamping end of the clamping and blanking stations;

FIG. I9 is a partly sectioned view of those stations as seen from the blanking end thereof;

FIG. 20 is a partly sectioned side view of the clamping and blanking stations;

FIG. ZI is a fragmentary and partly sectioned view showing one of the punches of the clamping station; and

FIG. 22 is a schematic view of that part of the circuitry that is concerned with the control of the conveying means.

Apparatus in accordance with the invention, as may be seen in FIG. I, has conveying means, generally indicated at 30, operable by a drive at the generally indicated indexing station 31, to convey a sheet 32 of a thermoplastic material step by step through a heating station, generally indicated at 33, to a forming station, generally indicated at 34. where, in the illustrative embodiment of the invention shown in the drawings, two transversely aligned articles, egg cartons 35 for example, are formed as an integral part of the sheet 32. The conveying means 30 advances the sheet and its thus formed cartons to a printing station, generally indicated at 36, and thereafter feeds the sheet 32 into a clamping and punching station, generally indicated at 37, and into a final station, generally indicated at 38 where the cartons 35 are blanked out from the sheet 32 and discharged in vertical stacks.

In practice, the sheet 32 is supplied in a roll and such a roll is shown as supported by a belt 39 trained about a pair of rolls 40 in a stand 4I. One of the rolls is driven by an electric motor 42, the operation of which is under the control of a normally closed switch 43. A counterweighted unit 44, pivotally mounted adjacent the infeed end of the conveying means 30,

is disposed to be engaged by the sheet 32 if a predetermined slack develops and then to be so actuated as to open the switch 43 thereby to interrupt the unwinding of the roll until the excess slack is taken up.

The conveying means consists of upper and lower transversely aligned pairs of

chains

45 and 46 whose proximate courses travel in the same direction and grip between them the margins of the sheet 32. At the infeed end of the apparatus. the

conveyors

45 and 46 are trained around

sprockets

47 and 48, respectively, see FIGS. 6-8. The

sprockets

47 and 48 are mounted on shafts 49, each supported by a pair of bearings 50 mounted in a housing 51. As the housings 51 are identical, only one is shown.

At the indexing station 31, see FIGS. 2-5, the upper chains are trained about sprockets 52 and under the rolls 53. The lower pair of chains 46 are trained about relatively large sprockets 54 and over rolls 55. The proximate courses of the chains are held in sheet gripping relation intermediate their ends and the intermediate stations by a series of pairs of spring-backed shoes 56, see FIG. I, attached to the upper pair of the side rails 57.

At the index station 31, see FIG. 2, there is a pair of spaced, parallel transverse slideways 58 mounted on the framework 59, the slideways 58 being shown as U-shaped and opening towards each other to receive marginal runners 60 on the lower portions of the

housings

61 and 62. As the housings 6] and 62 are identical, the same reference numerals are used to indicate corresponding parts.

The vertical, lengthwise walls 63 of both housings have bearing units 64 rotatably supporting a shaft, see FIG. 5, generally indicated at 65 and having a first section 66 and a second station 67, each shaft section having a sprocket 54 and a gear 68 fixed thereon, each gear 68 being within a housing. The shaft section 67 has a cylindrical portion 69 slidably receiving the shaft section 66 with a spline connection 70 between their overlapping ends to permit the shaft 65 to be shortened or extended.

Each housing wall 63 also has a bearing unit 7 I which, with a bearing unit 72 secured to a plate 73 mounted within the housing, support a stub shaft 74. Each stub shaft has a sprocket 52 and a gear 75 fixed thereon, each gear 75 being located within the appropriate housing and meshing with the gear 68 housed thereby.

Each housing has a nut 76 fixed to its bottom wall 77, the nuts 76 being oppositely threaded to receive oppositely threaded

portions

78A and 78B of a shaft 78 held captive by a yoke 79 fixed on the framework 59 at one side of the apparatus where the exposed end of the shaft 78 may have a crank, not shown, attached thereto to enable the shaft to be turned in one direction or the other to vary the spacing between the

housings

61 and 62, and, accordingly, the spacing both between the supporting chains 45 and between the holddown chains 46 as required by the width of the material being conveyed through the apparatus for its being marginally gripped.

The drive for the chains is at the index station 31 and includes a lever or actuator 80 supported within the housing 61 on the shaft section 66 by a bearing unit 81 for rotation independently thereof and located between the proximate gear 68 and a bearing unit 82 secured to an outer housing wall 83. One end of the actuator 80 carries a fluid pressure operated unit generally indicated at 84, an air-operated, double-acting piston-cylinder unit in the embodiment of the invention being described, best seen in FIG. 3, and operable to extend or retract an index pin 85 connected to its stem 86.

The other end of the actuator 80 is pivotally connected as at 87 to the stem 88 of a generally indicated, double-acting hydraulic ram 89 pivotally connected as at 90 to a subframe 9I depending from and secured to the bottom of the housing 6I. As the ram 89 is operated to extend or retract its stem 88, it causes the actuator 80 to swing first in one direction and then the other with the path of the index pin 85 having a predetermined arcuate path including a substantial number of a concentric circular series of uniformly spaced seats 92 in the outer face of the gear 68 within the housing 61 the index pin 85 being disposed and positioned to enter, when extended, any one of the seats 92 in axial alignment therewith.

With the index pin 85 entrant of a seat 92, the gear 68 and the actuator 80 are locked together so that, as the ram 89 is operated to extend its stem 88, the

sprockets

52 and 54 are turned to a predetermined extent in a clockwise direction as viewed in FIG. 5, advancing the chains and the sheet 32 held between them by one step. The predetermined step is established by stops and one of these may be a limit imposed by the construction of the ram 89 on the distance its stern may travel in one direction, in a step-producing direction with the indexing means being detailed or a stop 93 threaded in a support 93A and engageable by the end of the actuator 80 to which the stem of the ram 89 is connected. In this case, the stop determines the end of a step with the reset position being established by a stop 94 engageable by the end of the actuator 80 carrying the air operated unit 84. The stop 94, threaded in a mount 94A detachably attached to the support 95 which is arcuate with respect to the shaft 65 and located in the housing 51 close to the periphery of the gear 68. The mount 95A has an arcuate series of threaded seats 96, each in radial alignment with an appropriate one of the seats 92 during a dwell. The mount 94A is secured as by attaching it by bolts 97 threaded into a pair of seats 94 selected to place the stop 94 in the reset position defining with the step-ending stop the desired step length.

A power operated unit, generally indicated at 98, a hydraulically operated piston-cylinder unit in the embodiment of the invention being described, is supported by a mount 99 on a sidewall of the housing 61 and is operable to extend or retract a locking pin I00 secured to its stem [01, see FIG. 4. The unit 98 is so located and positioned that when its locking pin I00 is driven into its locking position, it enters an axially aligned seat 92 remote from the path of the index pin 85 and of the proximate end of the actuator 80.

By means subsequently described, the index pin 85 is withdrawn and the locking pin I00 operatively positioned at the end of a step and the valve means in control of the ram 89 operated to cause it to reset the actuator 80. The index pin is then rescaled. The operative position of the locking pin 100 is timer-controlled thereby to provide a dwell during which the operations at the several stations are performed with any movement of the conveying means positively prevented. At the end of the timed dwell, the locking pin is withdrawn. The timer is indicated at I02 and is shown only in FIG. 22.

The power-operated units at the indexing station 3I and the rams there and elsewhere are conventional as are the valves which control the fluid to effect their operation, the valves being operated by solenoids as is also conventional in the operation of such devices. The valves are, accordingly, not herein shown and while the switches are conventional, some of them are shown.

The control of the step-by-step advance of the conveying means is effected by

limit switches

103 and 104, see FIG. 2, in the housing 61 adjacent the periphery of the gear 68 therein, the limit switch I03 carried by the mount 94A to be engageable by the shoulder I05 of the air-operated unit 84 at the reset position of the actuator 80 and the limit switch I04 engageable by the proximate side of the actuator 80 at the stepending position of the actuator 80. The position of the limit switch I03 is, accordingly, adjusted with the stop 94 thus to enable the length of each step to be quickly and easily adjusted as required by the length of the articles to be fonned in the sheet material 32.

Adjustment of the spacing between the

sprockets

47 and 48 at the infeed end of the apparatus is necessary whenever the width of the sheet material 32 is to be changed. To this end, see FIGS. 6-8, each housing 51 for the

sprockets

47 and 48 has marginal flanges I07 supported in transverse tracks I08 supported on the framework 59 and shown as U-shaped and opening towards each other. Each housing SI has a threaded bore 109, the bores being of opposite hand thus to receive oppositely threaded portions 110 of a shaft 111. The shaft 111 is supported adjacent its ends by bearings 112 fixed on the framework 59 to be turned as by means of a crank thus to move the two housings 51 towards or away from each other as required by the width of material 32 that is to be used.

As shown in FIGS. 9-11, the forming station 34 has a base 113 supporting a pair of vertical, transversely aligned posts 114 connected at their upper end by a head 115. The head 115 pivotally supports a hydraulic ram 116 whose stem 117 is connected to an upper platen 118 slidably guided by the posts 114. The base 113 has a hydraulic ram 119 similarly connected thereto with its stem 120 connected to a lower platen 121 slidably guided by the posts 114.

The platen 118 has right and left upper molds 122 detachably attached thereto and complemental right and left lower molds 123 are detachably attached to the lower platen 121 and the platens carry stops 124 that become engaged when they are closed together thus to precisely space apart the upper and lower molds. Upper and

lower heat shields

125 and 126 are attached to each of the

molds

121 and 122, respectively, at the infeed end thereof. The bottom edges of the heat shield 125 are in the form of a tongue 127 disposed to enter the groove or channel 128 in the proximate edge of the heat shield 126 as will be apparent from FIG. from which and from FIG. 1 it will also be apparent that the heat shields separate the forming station 34 from the heating station 33 and that when the upper and lower molds are brought together, a transverse channel 129 is formed in the sheet 32 at the trailing ends of the cartons. The heat shields and the molds are water-cooled, water inlets and outlets being indicated, see FIG. 11 at 130 and 131.

At this point, attention is directed to the fact that until the sheet has cooled to a predetermined extent, it is easily deformed and the function of the channels 129 is to provide a narrow area where deformation can occur as the sheet 32, with its formed cartons, is stepped from the forming station 34, such deformation being illustrated in FIG. 10 at the outfeed ends of the molds.

It will be noted that the upper and lower platens I18 and 121 carry

actuators

132 and 133, respectively, the actuator 132 operating the limit switch 134 when the upper platen 118 is in its raised position and the actuator 133 operating the limit switch 135 when the lower platen 121 is in its lowered positron.

It will be appreciated that the interval in which the molds are closed against the sheet 32 must be such to ensure the formation of the egg cartons and their cooling to an extent ensuring against deformation and this interval is controlled by the timer 102.

The timing interval is relatively short due to the heat shields and to the provision of channels 129 that take any lengthwise stresses in the sheet and become deformed thereby without injury to the cartons.

It is, of course, the length of each article that is to be molded that determines the length of each step without waste of material and the width of the articles determined the width of the sheet material with the adjustment of the spacing of the two sets of chains making the use of different widths possible.

Cartons formed in the sheet material at the forming station 34 are stepped forwardly to the printing station 36 where indicia, if desired, is applied to the cover of each carton or to desired portions of other articles, see FIGS. 12-17. Even as the change in molds usually requires a change in the length of a step, the transverse spacing of the conveyor chains, or both, so are corresponding adjustments of the printers made necessary. For that reason, the printing station 36 has a pair of printing units 136 for printing a different color, for example, each unit being adjustable lengthwise of the apparatus and shown as including a pair of printers, one for each article that is to be formed during a dwell. Each printer is generally indicated at 137 and includes a printing plate 138 reciprocable into and out of printing contact with the desired portion of an article. As the printers 137 are identical, only one is detailed in the drawings. Each unit 136 also has a support 139 for each printer 137 reciprocable into and out of a position supporting that portion of an article to be printed while the printing plate 138 of that printer is in contact therewith, the supports 139 being shaped and dimensioned for use with the articles being produced. Each printer 137 and its support 139 are adjustable transversely of the apparatus, each independently of the other.

As may best be seen in FIG. 13, the sides of the framework 59 have slideways 140 in the form of channels opening towards each other and slidably supporting the margins of the baseplate 141 of each unit 136. Below the plane of each plate 141, there is a transverse shaft 142 supported at each end in a bearing mount 143 secured to the framework 59. Each shaft 142 has a pair of bevel gears 144 each in mesh with a bevel gear 145 on a shaft 146. Each shaft 146 is supported at one end in a bearing mount 143 and has its other end threaded and extending through a fixed nut 147 secured to the undersurface of the plate 141. Both ends of each shaft 142 are exposed and formed to enable a crank, not shown, to be fitted thereto thus to move the associated baseplate 141 and, accordingly, the appropriate unit 136 lengthwise into its correct position as determined by the step length which the indexing means has been set to provide.

Each unit 136 has a leg 148 secured to one side of the baseplate. The upper ends of the legs 148 of each unit are interconnected, see FIG. 14, by upper and lower transverse tracks 149 and 150 in slidable support of mounts 151, one for each printer 137, the mounts 151 of the rearward unit 136 extending rearwardly and those of the forward unit 136 extend ing forwardly, see FIG. 12. Each mount 151 includes an upwardly disposed support 152.

The upper part of each leg 148 has a bearing supported shaft 153 having an end 153A exposed and shaped for the attachment of a crank thereto. The other end 1538 of each shaft 153 is threaded through a nut 154 fixed on the proximate mount 151 thus to enable each printer mount 151 to be moved transversely to bring the printing plate 138 into a position in which, during a dwell, it may be brought into correct contact with the portion of the article that is to receive printing.

Each mount 151 has a pair of vertical gibs 155 for a slide 156 having spaced ears 157 in support of a pivot 158 connected to the stem 159 of an air-operated ram 160 pivotably secured to the upper end of the support 152.

Each slide 156 includes

bottom plates

161 and 162. The plate 161 has side bars 163 secured thereto and the plate 162 has an outwardly and upwardly inclined arm 164. On the inner surfaces of the side bars 163 there are flanges 165 which, with the undersurface of the plate 161 define a slideway for the printing plate 138, see FIG. 15. At the rear end of the slideway there is a stop I66 and, at its front end, a pivoted, plate-retaining latch 167. Rear or inner cam plates 168 are adjustably attached to the side bars 163 and front or outer cam plates 169 are attached to the sides of the plate 162.

At each side of the slide 156 there is a bracket 170 fixed to the mount 151 with each rotatably supporting a shaft 171. Adjacent one bracket 170, one end of a bellcrank 172 is fixed on the shaft 171 with its other end pivotally connected to the stem 173 of an air operated ram 174 pivotally connected to the upper end of the appropriate support 152.

An arm 175 is secured to the shaft 171 adjacent each of its ends. Each arm 175 slidably supports a pair of parallel rods 176 with the lower ends of corresponding rods rotatably supporting opposite ends of transverse, parallel ink rolls 177 yieldably urged upwardly for inking engagement with the printing plate 137 and provided with rollers 178 held in engagement with the front and

rear cam plates

168 and 169, respectively, by springs 179.

When air is delivered to the ram 174 of any printer to turn its shaft 171, the ink rolls 177 are swung upwardly away from their inking position into contact with the ink platen 180 rotatably supported adjacent the outer end of the arm 164 of that printer. Each printer has a rotatable ink roll 181 and an

Claims

1. In apparatus for forming articles from a roll of sheet material in a plastic state, a row of stations including an article forming station and at least one subsequent station, a conveyor extending through the stations and including a pair of supporting chains and a pair of hold down chains, the proximate chain courses gripping the margins of the sheet material, said article forming station including detachable, coacting forming members receiving the material between them, means operable to advance the conveyor a predetermined distance and reciprocable between reset and step-ending positions, a means operable to lock said conveyor against movement, control for operating said advancing and said locking means alternately to provide steps and dwells and spaced stop members whose spacing determines the step length and which are engageable by the advancing means, means supporting one of said members for movement relative to the other member to vary the extent to which the advancing means may travel thereby to enable the step length to be varied in relation to the length of the articles to be formed by the coacting members at the forming station, and a limit switch associated with each member and operated when that member is operative.

2. The apparatus of claim 1 in which the advancing means includes a rotatable driving member having a concentric series of equally spaced seats, an actuator coaxial with said driving member and rotatable independently thereof, an index pin supported at one end of said actuator for movement into and out of a seat-entering position, means connected to the other end of the actuator and operable to swing said actuator reciprocably between reset and step-ending positions, and the locking means includes a locking pin movable into and out of a seat-entering position.

3. The apparatus of claim 2 in which the supporting means for the movable member includes a series of positions for the second member disposed in sucH relation to the seat spacing as to enable the step length to be varied only by a distance ensuring pin seating.

4. The apparatus of claim 3 in which the supporting means for the movable member includes an arcuate series of equally spaced, threaded seats concentric with the seats of the driving member and establishing the positions of the movable member, each threaded seat being in radial alignment with a seat of the driving member when the actuator is in either its reset or its step-ending position, and a pair of threaded members threaded in appropriate threaded seats detachably attach the movable member to the supporting member.

5. The apparatus of claim 2 in which the locking pin and the index pin are both on the same side of the driving member with the locking pin located beyond the maximum arc the index pin may travel.

6. The apparatus of claim 5 in which the supporting means for the locking pin is a fluid pressure operated piston-cylinder unit, the end of the actuator to which the operating means therefor is attached is sufficiently short to have a path inwardly of the seats of the driving member, and the locking pin is located with said path between it and the axis of the driving member.

7. The apparatus of claim 1 and a pair of housings, supporting structure to which both housings are connected for sliding movement towards and away from each other transversely of the direction of travel of the material, a connection between the housings and mounted on the structure and operable to effect their equal movement, either towards or away from each other, chain supporting sprockets supported by the housings, a telescoping drive shaft on which the sprockets for one set of chains and the driving member are fixed, and driving connections between the shaft and the sprockets for the other set of chains.

8. The apparatus of claim 7 in which one driving connection includes the rotatable driving member.

9. The apparatus of claim 1 in which the subsequent station includes coacting members receiving the material between them, means to bring said members into coacting relationship during a dwell, and means operable to move said members lengthwise of the conveyed sheet material to place them in position to engage with an article formed at the forming station when it has advanced to the subsequent station.

10. The apparatus of claim 9 in which the coacting members of the subsequent station are movable transversely separately.

11. The apparatus of claim 9 in which the coacting members of the subsequent station are movable lengthwise as a unit.