US2686393A

US2686393A - End tucker and folder mechanism for wrapping machines

Info

Publication number: US2686393A
Application number: US269883A
Authority: US
Inventors: Russell Alexander
Original assignee: Forgrove Machinery Co Ltd
Current assignee: Forgrove Machinery Co Ltd
Priority date: 1952-02-04
Filing date: 1952-02-04
Publication date: 1954-08-17
Anticipated expiration: 1971-08-17

Description

A. RUSSELL Aug. 17, 1954 END TUCKER AND FOLDER MECHANISM FOR WRAPPING MACHINES 5 Sheets-Sheet 1 Filed Feb. 4, 1952 A. RUSSELL Aug. 17, 1954 END TUCKER AND FOLDER MECHANISM FOR WRAPPING MACHINES 5 Sheets-Sheet 2 Filed Feb. 4, 1952 Aug. 17, 1954 RUSSELL 2,686,393

END TUCKER AND FOLDER MECHANISM FOR WRAPPING MACHINES Filed Feb. 4, 1952 5 Sheets-Sheet 3 1954 A. RUSSELL 2,686,393

END TUCKER AND FOLDER MECHANISM FOR WRAPPING MACHINES Filed Feb. 4, 1952 5 Sheets$heet 4 Aug. 17, 1954 A. RUSSELL 5 3 END TUCKER AND FOLDER MECHANISM FOR WRAPPING MACHINES Filed Feb. 4, 1952 5 sheets-sheet s Patented Aug. 17, 1954 UNITED STATES ATENT OFFICE END TUCKER AND FOLDER MECHANISM FOR WRAPPING MACHINES Application February 4, 1952, Serial No. 269,883

7 Claims. (Cl. 5313 This invention relates to Wrapping machines of the type comprising an intermittently rotating wrapping wheel having a number of articlereceiving pockets and arranged to move the pockets in succession from a receiving station, at which an article, with a wrapper folded around it in U formation, is lifted into the pocket, to a folding station, means coacting with the Wrapping wheel to fold the depending ends of the wrapper against the article in each pocket prior to its arrival at the folding station, a pair of reciprocating end tuckers at the folding station for forming a centre tuck in each projecting end of the wrapper on the article at the folding station and two pairs of opposed rotary end folders, located at opposite sides of the article at the folding station, arranged to move inwardly, after the end tuckers have completed their forward movement, to fold the projecting ends of the wrapper at each end of the article over the centre tucks.

In such a machine it has been the conventional practice to use thin steel end tuckers, fixed to a reciprocating carrier and set close to the ends of the article to ensure neat tucking and neat end folding by the rotary end folders. The end tuckers must, of course, be thin, to allow the end folders nearer to the receiving station to move close to the ends of the article prior to retraction of the end tuckers.

Where, however, the machine is employed for wrapping blocks of plastic material, such for example as hutter or margarine, difficulties are en countered. If the end tuokers are set close to the block, the contact of the soft material of the block with the tuckers often tends to spoil the shape of the block. Setting the end tuckers further away from the block to avoid this makes it necessary to set further away from the block the rotary end folders nearer the receiving station in order to avoid fouling the end tuckers, and this causes loose folding of the wrapper on the ends of the block.

With a view to avoiding this disadvantage, the invention provides a wrapping machine of the above type in which the end tuckers are hinged to a reciprocating carrier arranged at each ma chine cycle to execute a forward stroke towards the pocket of the wrapping wheel dwelling at the folding station followed by a return stroke, and comprising mechanism coacting with the end tuckers and arranged to move them gradually inwards from an open position to a partially closed position during the forward stroke of the carrier and to move them further inwards to the fully closed position after the carrier has completed its forward stroke, said tuckers remaining in the fully closed position, during the return stroke of the carrier, until the rotary end folders have completed their inward movement. In this way, the end tuckers are prevented from spoiling the shape of the block, while nevertheless allowing the rotary end folders nearer the receiving station to move up close to the end of the block and so ensure tight end folding.

Preferably, the end tuckers are spring urged towards the closed position and are controlled by linkages actuated from the driving mechanism of the end folders, the linkages allowing the end tuckers to close towards the ends of the block during forward movement of the end tuckers and the closing movement of the end tuckers being completed, under the control of cams on said driving mechanism, when the end folders begin their rotational movement toward the block.

One form of wrapping machine according to the invention for wrapping blocks of plastic material will now be described in detail, by way of example, with reference to the accompanying drawings, in which:

Fig. 1 is a side elevation showing the wrapping wheel and the tucking mechanism at the folding station,

Fig. 2 is a section, on a larger scale, on the line II-II in Fig. 1,

Fig. 3 is a plan view of the upper rotary end folders,

Fig. 4 is a section, with certain parts omitted for clarity, on the line IVIV in Fig. 1,

Fig. 5 is an and elevation, on a reduced scale, looking from the left hand side of Fig. 1,

Fig. 6 is a diagrammatic view, showing the position of the end folders when closed against a block of plastic material and Figs. 7-12 are diagrammatic perspective views showing successive stages in the folding of a wrapper around a block.

Like reference numerals designate like parts throughout the figures.

The machine comprises a wrapping wheel ID, of the construction described in U. S. application Serial No. 269,884, now U. S. Patent 2,543,501, arranged to be intermittently rotated on a shaft ii. The wrapping wheel 18 has four pockets, each comprising a base plate l2 and a pair of pivoted side jaws iii. The pockets are moved in succession from a receiving station A to a folding station B, and thence to a top pressing station C and to a discharge D, each pocket dwelling at each of said stations. While a pocket is dwelling at the receiving station A a cam operated lever I4 operates to impart downward movement to a bar 15, on the end of which the base plate ll of the pocket is resiliently mounted by springs, one of which is shown at IS in Fig. 1. Downward movement of the bar [5 causes, through linkages I1, the side jaws I3 to move outwardly to the position shown in Fig. 1, as described in U. S. application Serial No. 269,884, now U. S. Patent 2,643,501. A lifting member [8 then rises to lift a block I 9 of butter or the like into the pocket at the receiving station, the block carrying with it into the pocket a wrapper 20, which has been fed along guides 2| into position above the block as described in U. S. application Serial No. 269,884, now Patent 2,643,501. As the block l9 ascends into the pocket, the base plate l2 rises and the side jaws l3 close to grip the block, thereby folding the wrapper in U formation, as indicated in Fig. 7, about the block. After the block l9 has been gripped by the side jaws 13, the lifting member 18 descends, and a blade 22 is then moved, by conventional mechanism not shown, to fold against the base of the block the depending portion H of wrapper at the right hand side of the block (see Fig. 8). Then the wrapping wheel I rotates anti-clockwise to bring the partially wrapped block to the folding station B, a fixed blade 23 folding the left hand depending portion 12 of the wrapper against the base of the block 19 during its travel from station A to station B.

Fig. 9 shows the block I9 on arrival at station B. It has been turned through 90 in relation to the position of Figs. 7 and 8 and the portions H, 12 of wrapper are shown folded against its base. As will be noted, a tubular portion of wrapper projects from each end of the block.

Opposite the folding station B is a bracket 24, fixed to a member 26 of the machine frame, in which is slidably mounted a hollow rod 25. The rod 25 is coupled by a link 21 to a bell crank 28. pivoted on a shaft 29 and carrying a follower 30 coacting with a cam 3| (see Fig. on a cam shaft 32. The cam 3i reciprocates the rod 25 to move it forwardly towards the wrapping wheel and thereafter to retract it.

On the forward end of the rod 25 is mounted a carrier 33 to which are pivoted, on vertical hinge pins 34 (Fig. 2), two end tuckers 35. A compression spring 36 tends to urge the tuckers 35 towards the closed position, but their movement is controlled by extensions 31 of the tuckers, which project beyond the hinge pins 34 and coact each with a roller 38. Each roller 38 is carried on a bell crank 39 (Fig. 4) pivoted on a fixed pin 40, and carrying a follower 4| coacting with a cam 42 on a shaft 43. The shafts 43 serve, as later described, to impart rotary movement to the upper end folders 44 (Figs. 1 and 3).

Prior to commencement of the forward stroke of the carrier 33, the cams 42 maintain the bell cranks 39 in the positions shown in Fig. 4 in which, see Fig. 2, the rollers 38 coact with the outer faces of the extensions 31 so holding the end tuckers 35 in open position. As the end tuckers 35 move in towards the block 19, the distance between the hinges 34 and the points of contact of the rollers 38 with the extensions 3'! increases. so that the end tuckers gradually close towards the ends of the block, the end tuckers 35 being nearly but not quite closed when they have completed their fqorward movement as indicated in chain dotted lines in Fig. 2. The movement of the end tuckers 35 produces a centre tuck 13 in 4 the tubular portion of wrapper at each end of the block as shown in Fig. 10.

The shafts 43 (see Fig. 5) carry gears 45 which mesh with one another and with a gear 46 meshing with a horizontally reciprocable rack 4'! coupled by a link 48 to a bell crank 49 pivoted on a fixed stud 50. The bell crank carries at its lower end a follower 5| coacting with a cam 52.

As soon as the end tuckers 35 have completed their forward movement the cam 52 rocks the bell crank 49 to draw the rack 41 to the left, as seen in Fig. 5, thereby rotating the shafts 43 in the direction to rotate the upper end folders 44 towards the block [9. The rollers 41 (Fig. 4) consequently ride off the high portions of the cams 42, thereby enabling the spring 36 (Fig. 2) to close the end tuckers on the block. The end tuckers 35 remain so closed during their return movement, and are opened again only when the end folders 44 have later returned to their initial position.

One of the gear wheels 45, (i. e. that shown to the left in Fig. 5) meshes with a gear 53 (Fig. l) rotatably mounted on the bracket 24 and meshing with one of a pair of gears 54. The gears 54 are splined, each to one of a pair of shafts 55. The shafts 55 are coupled together by a cross head 56 and carry the bottom end folders 51.

The bottom end folders 51 need to be initially retracted, so that they do not foul the wrapping wheel pocket approaching the folding station. The cross head 55 connecting the shafts 55 is coupled, by a link 58, to a bell crank 59 pivoted on the shaft 29. The bell crank carries a follower 60 coacting with a cam 6|, which causes the bottom end folders 51 to move forward towards the block with the end tuckers 35. The shafts 55 dwell in the forward position while the bottom end folders 51 rotate inwards, this action taking place during the retraction of the end tuckers 35. Conse quently the bottom end folders 51 can fold the ends of the wrapper closely against the block l9 as shown in Fig. 6. They remain in their inwardly rotated position as the block l9 moves on to the top pressing station. The bottom end folders 51 begin to rotate back to their initial position after the block I9 has cleared them, and the shafts 55 carrying them are then retracted to their initial position. The bottom end folders 51 produce a fold 14 (Fig. 11) at each end of the block and the top end folders 44 produce a fold 75 at each end of the block.

The top end folders 44 are set so that, in their extreme position of inward rotation, their faces 62 (see Fig. 6) are not quite in contact with the ends of the block l9. Therefore they do not foul the bottom end folders 51. The top end folders, however, have extensions 63 which, in the position of extreme inward rotation, extend above and close to the ends of the block. As, therefore, the block travels up between these extensions 63 on its way to the top pressing station, the top end folds 15 are pressed down on to the ends of the block.

The carrier 33 for the end tuckers carries a pressure plate 64 (Fig. 2) attached to a rod 65 housed within the tubular shaft 25 and urged outwardly by a spring 65. Another rod 6'! fixed to the pressure plate is mounted to slide in a bracket 68 on the carrier 33 and nuts 69 on the rod coact with the bracket 68 when the pressure plate is in its extreme outward position as shown in Fig. 2. When the carrier 33 moves forward towards the block IS, the presser plate is brought into contact with the longitudinal fold 10 (see Fig.

6) in the outwardly facing face of the block, and is maintained in pressure contact with this fold by compression of its spring 65 during the further forward movement of the carrier 33.

As the result of the action, at the folding station 3, of the end tuckers 35 and the rotary end folders M, 57 a triangular wing 16 (Fig. 11) of wrapper only is left projecting from each end of the block. These wings are folded down, in conventional manner, by slots in stationary end plates (not shown) as the block moves on to the top pressing station C. Fig. 12 shows the block at station C and with the wings 16 of wrapper folded down. Here a top presser (also not shown) descends on the block to press it. Finally, at the discharge station D the block is discharged from the pocket in a direction parallel to the axis of the wrapping wheel.

What I claim as my invention and desire to claim by Letters Patent is:

l. A wrapping machine comprising an intermittently moving conveyor for traversing in succession to a folding station partially wrapped articles, each of which is enclosed by a wrapper having tubular portions projecting from each end of the article, said conveyor having a plurality of pockets each for holding one of said partially wrapped articles, a reciprocating carrier at the folding station, means operative at each machine cycle to impart to said carrier a forward stroke towards the pocket at the folding station followed by a return stroke, a pair of end tuckers hinged to said carrier for movement towards and away from the ends of the article at the folding station, said end tuckers serving to form a centre tuck in each tubular projecting end of the wrapper on the article at the folding station, two pairs of rotary end folders, located on opposite sides of the article at the folding station, said end folders being rotatable about axes at right angles to the hinge axes of said end tuckers, actuating means for rotating said end folders inwardly towards the end of the article, after said end tuckers have completed their forward stroke, to form over said centre tucks superposed end folds in the projecting ends of the wrapper, springs urging said end tuckers in the direction to close on the ends of the article at the folding station, a fixed structure, members mounted on said fixed structure and coacting with said end tuckers to allow them to close gradually to a partly closed position during the forward stroke of said carrier, and means controlled by the actuating means of said end folders for actuating said members to cause movement of said end tuckers to the fully closed position during the inward movement of said end folders and after the carrier has completed its forward stroke, said end tuckers remaining in the fully closed position, during the return stroke of the carrier, until said rotary end folders have completed their inward movement.

2. A wrapping machine as claimed in claim 1, wherein said members coacting with said end tuckers are bell cranks pivoted on said fixed structure and comprising cam mechanism operable by the actuating means of said end folders, followers on said bell cranks coacting with said cam mechanism, and rollers on said bell cranks coacting with extensions on said end tuckers at the sides of the hinges thereof remote from said tuckers, said bell cranks allowing of gradual closing movement of the end tuckers as said hinges move away from said rollers during the forward stroke of the carrier and being movable by said cam mechanism, after the carrier has completed its forward stroke, to allow of movement of the end tuckers to the fully closed position.

3. A Wrapping machine, comprising an intermittently rotating wrapping wheel having a number of article-receiving pockets, said pockets being movable to traverse partially wrapped articles in succession from a receiving to a folding station, each article on arrival at the folding station being enclosed in a wrapper havin tubular portions projecting from each end of the article, a reciprocating carrier at the folding station, means operative at each machine cycle to impart to said carrier a forward stroke towards the pocket at the folding station followed by a return stroke, a pair of end tuckers hinged to said carrier for movement towards and away from the ends of the article at the folding station, said end tuckers serving to form a centre tuck in each tubular projecting end of the wrapper on the article at the folding station, two pairs of rotary end folders at the folding station, one pair of which is nearer to said receiving station than the other pair, and is mounted for reciprocation in a direction parallel to that in which said carrier reciprocates, said end folders being rotatable about axes at right angles to the hinge axes of said end tuckers, means for rotating said end folders inwardly towards the ends of the article, during the return stroke of said end tuckers, to form over said centre tucks superposed end folds in the projecting ends of the wrapper, mechanism coacting with the end tuckers and arranged to move them gradually inwards from an open position to a partially closed position during the forward stroke of the carrier and to move them further inwards to the fully closed position after the carrier has completed its forward stroke, said end tuckers remaining in the fully closed position, during the return stroke of the carrier, until said rotary end folders have completed their inward movement, and means for moving said nearer end folders forwards with the end tuckers and retaining them in the forward position, as the carrier performs its return stroke and said end folders move inwardly, until the wrapping wheel has withdrawn the article to be wrapped from position between the end folders.

4. A wrapping machine, comprising an intermittently rotating wrapping wheel having a number of article-receiving pockets, said pockets bein movable to traverse partially wrapped articles in succession from a receiving to a folding station, each article on arrival at the foldin station being enclosed in a wrapper having tubular portions projecting from each end of the article, a reciprocating carrier at the folding station, means operative at each machine cycle to impart to said carrier a forward stroke towards the pocket at the folding station followed by a return stroke, a pair of end tuckers hinged tosaid carrier for movement towards and away from the ends of the article at the folding station, said end tuckers serving to form a centre tuck in each tubular projectin end of the wrapper on the article at the folding station, two pairs of rotary end folders at the folding station, one pair of which is nearer to said receiving station than the other pair, said end folders being rotatable about axes at right angles to the hinge axes of said end tuckers, means for rotating said end folders inwardly towards the ends of the article, during the return stroke of said end tuckers, to form over said centre tucks superposed end fold in the projecting ends of the wrapper, and mechanism coacting with the end tuckers and arranged to move them gradually inwards from an open position to a partially closed position during the forward stroke of the carrier and to move them further inwards to the fully closed position after the carrier has completed its forward stroke, said end tuckers remaining in the fully closed position, during the return stroke of the carrier, until said rotary end folders have completed their inward movement, said rotary end folders remote from the receiving station bein shaped so that, when in their extreme position of inward rotation, their faces are clear of the other pair of end folders, said remote rotary end folders having extensions which, in said extreme position of inward rotation of said folders, are effective to press down the end folds against the article on movement of the wrapping wheel to carry the article forward from the folding station.

5. A wrapping machine comprising an intermittently moving conveyor for traversing in succession to a folding station partially wrapped articles, each of which is enclosed by a wrapper having tubular portions projecting from each end of the article, said conveyor having a plurality of pockets each for holding one of said partially wrapped articles, a reciprocatin carrier at the folding station, means operative at each machine cycle to impart to said carrier a forward stroke towards the pocket at the folding station followed by a return stroke, a pair of end tuckers hinged to said carrier for movement towards and away from the ends of the article at the folding station, said end tuckers serving to form a centre tuck in each tubular projecting end of the wrapper on the article at the folding station, two pairs of rotary end folders, located on opposite sides of the article at the folding station, said end folders being rotatable about axes at right angles to the hinge axes of said end tuckers, mechanism coacting with the end tuckers and arranged to move them gradually inwards from an open position to a partially closed position during the forward stroke of the carrier and to move them further inwards to the fully closed position after the carrier has completed its forward stroke, said end tuckers remaining in the fully closed position during the return stroke of the carrier, and actuating means for rotating said end folders inwardly towards the ends of the article during the return stroke of said end tuckers to form over said centre tucks superposed end folds in the projecting ends of the wrapper.

6. A wrapping machine, comprising an intermittently rotating wrapping wheel having a number of article-receiving pockets, said pockets being movable to traverse partially wrapped articles in succession from a receivin to a folding station, each article on arrival at the folding station being enclosed in a wrapper having tubular portions projecting from each end of the article, a reciprocating carrier at the folding station, means operative at each machine cycle to impart to said carrier a forward stroke towards the pocket at the folding station followed by a return stroke, a pair of end tuckers hinged to said carrier for movement towards and away from the ends of the article at the folding station, said end tuckers serving to form a centre tuck in each tubular projectin end of the wrapper on the article at the folding station, two pairs of rotary end folders at the folding station, one pair of which is nearer to said receiving station than the other pair, said end folders being rotatable about axes at right angles to the hinge axes of said end tuckers, mechanism coacting with the end tuckers and arranged to move them gradually inwards from an open position to a partially closed position during the forward stroke of the carrier and to move them further inwards to the fully closed position after the carrier has completed its forward stroke, said end tuckers remaining in the fully closed position during the return stroke of the carrier, and actuating means for rotating said end folders inwardly towards the ends of the article during the return stroke of said end tuckers to form over centre tucks superposed end folds in the projecting ends of the wrapper.

7. A wrapping machine comprising an intermittently moving conveyor for traversing in succession to a folding station partially wrapped articles, each of which is enclosed by a wrapper having tubular portions projecting from each end of the article, said conveyor having a plurality of pockets each for holding one of said partially wrapped articles, a reciprocating carrier at the folding station, means operative at each machine cycle to impart to said carrier a forward stroke towards the pocket at the folding station followed by a return stroke, a pair of end tuckers hinged to said carrier for movement towards and away from the ends of the article at the folding station, said end tuckers serving to form a centre tuck in each tubular projecting end of the wrap per on the article at the folding station, two pairs of rotary end folders, located on opposite sides of the article at the folding station, said end folders being rotatable about axes at right angles to the hinge axes of said end tuckers, mechanism coactin with the end tuckers and arranged to move them gradually inwards from an open position to a partially closed position during the forward stroke of the carrier, actuating means operating when the end tuckers have completed their forward movement for rotating said end folders inwardly towards the ends of the article to form over said tucks superposed end folds in the projecting ends of the Wrapper, and means operated by said actuating means for moving said end tuckers to the fully closed position during the initial stage of inward rotation of said end folders, said carrier thereafter retracting said closed end tuckers from the article prior to completion of inward rotation of said end folders.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,026,356 Lee May 14, 1912 1,545,513 Peters et a1 July 14, 1925 1,940,375 Smith Dec. 19, 1933 2,110,815 Parsons Mar. 8, 1938