US3585784A

US3585784A - Automatic wrapping machine

Info

Publication number: US3585784A
Application number: US829931A
Authority: US
Inventors: Fritz F Trieber; James H Frenchy
Original assignee: Corley Miller Inc
Current assignee: Corley Miller Inc; Hobart Corp
Priority date: 1969-06-03
Filing date: 1969-06-03
Publication date: 1971-06-22
Anticipated expiration: 1988-06-22

Abstract

In an automatic wrapping machine which has means for moving a package into a sheet of wrapping film adjacent the free end of the film to cause preliminary wrapping of the film about the package with the free end of the film under the package and for banding the film about the package as the package is moved in a predetermined path to complete the wrapping of the film about the package and to overlap the free end of the film, an improvement which comprises palletlike means on which rests at least the portion of the package over which the free end of the film is wrapped for holding the film at the free end thereof against the package while the package is moved in said predetermined path to complete the wrapping of the film about the package. The palletlike means moves with the package and prevents the free end of the film from parting therefrom and thereby insures a complete wrap of the film about the package.

Description

United States Patent Inventors Fritz F. Trieber Niles; James H. Frenchy, Chicago, both of, Ill. Appl. No. 829,931 Filed June 3, 1969 Patented June 22, 1971 Assignee Carley-Miller, inc.

AUTOMATIC WRAPPING MACHINE 9 Claims, 8 Drawing Figs.

US. Cl 53/210 Int. Cl i B65b 1 1/40 Field of Search 53/210 References Cited UNITED STATES PATENTS 2,385,706 9/1945 Jensen 53/210 3,293,826 12/1966 Hansen et al. 53/228 1/1970 Hansen,Jr.et al. 53/210 Primary Examiner-Theron E. Condon Assistant ExaminerNeil Abrams Attorney-Hofgren, Wegner, Allen, Stellman and McCord ABSTRACT: In an automatic wrapping machine which has means for moving a package into a sheet of wrapping film adjacent the free end of the film to cause preliminary wrapping of the film about the package with the free end of the film under the package and for banding the film about the package as the package is moved in a predetermined path to complete the wrapping of the film about the package and to overlap the free end of the film, an improvement which comprises palletlike means on which rests at least the portion of the package over which the free end of the film is wrapped for holding the film at the free end thereof against the package while the package is moved in said predetermined path to complete the wrapping of the film about the package. The palletlike means moves with the package and prevents the free end of the film from parting therefrom and thereby insures a complete wrap of the film about the package.

/)d i T PATENTEU JUN22 IQYI SHEET 1 OF 3 I ia/e,

Ja 1 ld whwb SHEET 2 OF 3 ATENTEU JUN??? r97;

PATENTEU JUNE 2191] SHEET 3 BF 3 AUTOMATIC WRAPPING MACHINE BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to automatic package wrapping equipment and more particularly to an improvement in automatic wrapping machines of the general type shown in Treiber US. Pat. No. 3,429,098, entitled Automatic Wrapping Machine" and dated Feb. 25, I969.

Said patent relates to an automatic wrapping machine having package forming means extending along a path and with structure for preliminarily placing film around the package, including an infeed conveyor beneath the path and a transfer platform adjacent the infeed conveyor and movable toward and away from the infeed conveyor to receive a package therefrom and then move to a spaced location to permit a package elevator to move downwardly to a position adjacent the transfer platform and the infeed conveyor. The elevator has clamping means for the leading edge of the wrapping film to draw the film downwardly whereby movement of the package onto the elevator will cause preliminary wrapping of the film about the package with the free end of the film beneath the package. The package elevator is movable upwardly and the package is movable from the elevator into said path to complete the wrapping of the package as the film is banded thereabout. This invention relates to an improvement in such wrapping machines and comprises means for holding the film at the free end thereof against the underside of the package while the package is being transferred from the elevator into said path and thereby insures a complete wrap of the film about the package. I-Ieretofore, problems have been encountered in certain situations by the leading edge of the film becoming loose or tearing away from the underside of the package when the package is pushed from the elevator into said path. As a result, as the film is completely banded about the package, with the leading edge of the film torn away from the package, no overlap of the film is provided and a tight seal is prevented.

More particularly, the present invention includes a palletlike means which is mounted on the elevator for reciprocating movement toward and away from the transfer platform and toward and away from one end of said path. At least the portion of the package over which the free end of the film is wrapped rests on the pallet so that the pallet holds the free end of the film against the bottom of the package. The pallet moves with the package as the package is moved into the film from the transfer platform to the elevator and moves with the package as the package is transferred from the elevator into said path, thereby holding the free end of the film in position beneath the package so that the package is completely wrapped with the film overlapping said free end.

Other objects, features and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial front elevational view of the automatic wrapping machine of this invention, partially in section and portions thereof shown schematically, and showing the first of a series of views illustrating the sequence of operation of the machine;

FIG. 2 is a partial top plan view of the machine shown in FIG. I;

FIG. 3 is a view similar to FIG. I, on an enlarged scale and partially cut away, showing a succeeding position of certain machine components in the wrapping cycle;

FIG. 4 is a view similar to that of FIG. 3, partially cut away, showing a third succeeding position of the machine components in the wrapping cycle;

FIG. 5 is a view similar to FIG. 4 showing a fourth position of the machine components in the wrapping cycle;

FIG. 6 is a view similar to FIG. 4 showing a fifth position of the machine components in the wrapping cycle;

FIG. 7 is a view similar to FIG. 3 showing a sixth position of the machine components in the wrapping cycle; and

FIG. 8 is a vertical section taken generally along the line 8-8 of FIG. 2, but showing the final step in the wrapping cycle.

DETAILED DESCRIPTION OF THE INVENTION While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will be described herein in detail an embodiment of the invention together with a modification thereof with the understanding that the present disclosure is tobe considered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiments illustrated. The scope of the invention will be pointed out in the appended claims.

As pointed out above, the improvement of the present invention is preferably embodied in a wrapping machine similar to the type shown in Treiber US. Pat. No. 3,429,098. The wrapping machine is shown generally (partially schematically) in FIG. I and includes an infeed conveyor, indicated generally at A, at one end of the machine which receives a package of meat or the like having a tray or board, as indicated generally at B, on which the product is placed, with the infeed conveyor advancing the product onto a transfer platform, indicated generally at C, which can move between the retracted position shown in FIG. 1 and an advanced position adjacent the infeed conveyor A when it is to receive a package. After the package is received on the platform C the platform returns to the position shown in FIG. 1 for transfer of the package to an elevator indicated generally at D, with the initial wrapping occurring as the package is advanced onto the elevator and further being accomplished as the elevator is elevated from a lower position to the position shown in FIG. 1 where handing the wrapping film about the package is completed as the package is moved substantially off of the elevator. An overhead conveyor system (not shown in the drawings) advances the package through a wrapping station, indicated generally at F, where the end sections of the wrapping material are folded progressively under the package. The film layers at the underside of the package are then heat sealed on a hot plate, indicated generally at G, and the package is then discharged from the machine at an exit end opposite from the entry end.

Before proceeding with a detailed description of the improvement of this invention the general sequence of operation of the machine can best be understood by reference to FIGS. 1 and 3 through 8 which show steps or sequential positions of the various machine components and the package during the operating cycle of the machine. As shown in FIG. 1, a package advances from the initial position on the infeed conveyor A to a position on the'transfer platform C which in broken lines is shown in its advanced position adjacent the infeed conveyor. During this time the elevator D is in its upper position to provide an unobstructed path for movement of the transfer platform C. Following delivery of the package onto the transfer platform, the platform returns to its right-hand retracted position, as shown in full lines in FIG. I, to provide a gap between it and the infeed conveyor A so that the elevator D can descend to an inclined position in the space, as shown in FIG. 3. During the lowering movement of the elevator, film H is drawn downwardly by the gripping mechanism on the elevator to extend vertically across the path of a package which is pushed off the transfer platform C onto the elevator, as shown in FIGS. 4 and 5. This action of pushing the package into the film results in release of the film from the gripping mechanism on the elevator to have the leading edge of the film underneath the package as shown in FIGS. 5 through 8 and with the adjacent film extending over the package. The elevator D then ascends to its upper horizontal position shown in FIGS. 6 through 8 to substantially complete the wrapping of the film about the package. The film wrapped about the package is cut off from the supply length thereof and as the package is pushed off the elevator D the wrapping is completed and a hot 5 wire (for soft film) seals the overlapped film at the underside of the package, forming a tuck seal with opposite ends of the film extending from the package.

As shown in FIG. 7, the film is cut ofi from the supply length by cutting mechanism in part carried by the elevator and simultaneously the leading edge of the film supply is inserted between gripping mechanism on the underside of the elevator. By this time, a succeeding package has been placed on the transfer platform C and the platform has returned to its retracted position awaiting the next descent of the elevator D for wrapping the next package.

For a general description of the film feed mechanism, reference is made to FIG. I where it is seen that the film is supplied to the wrapping machine from a roll of film indicated generally at R which is supported at the periphery thereof by a pair of relatively large driven rollers and 11. An idler or dancer roller 12 is mounted on spaced pivot arms I4 and positioned within a loop of the film H. A clutch which controls rotation of the rollers 10 and 1 1 is controlled by a limit switch 16 mounted on the frame of the machine whereby the normally closed limit switch is held open when the loop of film is relatively large as shown in FIG. 1 and is permitted to close when the loop shortens. The operation of switch I6 is controlled by an actuator plate 18 carried on the lower end of one of the idler support arms 14. When the loop shortens, the limit switch 16 closes and a clutch (not shown) engages to drive the rollers 10 and 11 to add additional film to the loop in which the idler 12 engages. The loop of film in which the idler l2 rests is defined by a pair of rollers 18 and I9 fixed to the frame of the machine and extending transversely thereof. The film travels from roller 19 over a pair of

rollers

20 and 21 spaced from each other to provide a gap therebetween in which an intermediate film loop can be formed in which a back speed roller 22 rests to exert tension on the film intermediate the loop at the supply roll and the wrapping station having elevator D. The film then passes between rollers 24 extending transversely of the frame and the film partially wraps about one or the other of these during the wrapping operation. For additional support of the film through the machine, a pair of

support plates

26 and 27 are mounted to the frame with the plate 26 spanning the space between the

rollers

20 and 24 and the plate 27 spanning the space between the

rollers

19 and 21. In order to prevent the retrograde movement of the film, a nonrotating snubbing roll 28 is mounted on a pivoted arm 30 disposed at an angle whereby film can readily travel from right to left as viewed in FIG. I but any tendency for movement in the opposite direction will be prevented by the wedge action of the snubbing roll 29.

The transfer platform C has a platform pusher 32 which overlies a platform base 34 and is cycled to be in a rearward position as shown in FIG. I in full lines when a package is received on the transfer platform and subsequently to push a package off the transfer platform onto the elevator D as shown in FIGS. 4 and 5. Reference can be made to the aforementioned Treiber patent for structure details of the platform pusher and its cycling in the operation of the machine.

The package elevator D embodies an elevator base 36 which is generally rectangular in plan view and which operates at a wrapping station between an upper package discharge level as shown in FIGS. 1, 7 and 8 where the elevator is generally horizontal and a lower package receiving position at which the elevator is in an inclined position to receive a package from the transfer platform C as shown in FIGS. 3 through 5. The elevator is mounted for movement between the positions on a four-arm linkage system having upper arms 38 and lower arms 40, shown schematically in FIG. 1. Details of construction of the elevator may be ascertained by reference to the aforesaid patent. It should be pointed out that the elevator D has mounted along the edge thereof and beneath the base 36 a transversely extending knife member 42 which coacts with a cyclically movable knife 44 movably mounted on the frame of the machine and cycled in a manner later to be described. The elevator also has film gripping structure for gripping the leading edge of the film with this structure including an upper gripper member extending transversely of the elevator and defined by the undersurface of the knife blade 42 carried by the elevator. The other part of the gripping structure includes a transversely extending plastic rib 46 mounted at the ends of a pair of spaced arms 48 which extend beneath the elevator. The gripping member 46 is urged against the knife member 42 by spring means (not shown in the drawings).

The operation of the elevator in handling the film can now be described more completely. It will be seen that in FIG. 1 the leading edge of the film H has been inserted between the gripping members. The elevator D then lowers to the position shown in FIG. 3 with the film being drawn downwardly by the gripping members on the elevator. In FIGS. 4 and 5 the package is shown as having been moved by the platform pusher 32 onto the elevator into engagement with a front plate 50a of a package pusher block 50 (to be described in greater detail hereinafter) with the film being released from the gripping members. In FIGS. 7 and 8, the film has been completely wrapped around the package and the package is being moved from the elevator by an elevator pusher 51, which pushes against the pusher block 50, with the film about the package being cut off by the knife 44 coacting with the knife blade 42 on the elevator and at the same time the new leading edge of film is inserted between the gripping members for the next operation. Reference may be made to the aforementioned patent for structural details of the elevator pusher SI and its cycling in the operation of the machine.

I-Ieretofore, problems have been encountered in certain situations by the leading edge of the film becoming loose or tearing away from the underside of the package when the package is pushed from the elevator by the elevator pusher 51, as set forth in the preceding paragraph. This is caused to an extent by meat and fat particles coating the top surface of the elevator and making the surface sticky. The particles many times are carried by the underside of the packages B. To solve these problems, means have been provided for holding the free end of the film against the underside of the package while the package is being transferred from the elevator D into the path defined by wrapping station F and hotplate G to prevent the film from contacting the elevator surface and thereby insure a complete wrap of the film about the package by overlapping the ends of the film as shown in FIG. 8. This means comprises a palletlike support member, generally designated 52, which is mounted on the upper surface of the elevator base 36 for free reciprocating movement toward and away from the transfer platform C and the wrapping station F. The palletlike support member 52 includes a generally flat base 54 which overlies a portion of the elevator base 36, and upstanding latch portions 56 at the left end of the base 54, as seen in the drawings (the end of the base furthest away from the transfer platform C and wrapping station F). Referring to FIGS. 2 and 8, the elevator base 36 has a slot 58 through which extends a pair of bushings 60 which are secured to the base 54 of the pallet for guiding the pallet in its free reciprocating movement.

Referring to FIG. 8, the pusher block 50 on which is secured an abutment in the form of the package engaging front plate 50a is mounted on top of the pallet base 54 for reciprocating movement relative to both the pallet 52 and the elevator base 36. The pusher block 50 is a two-part block which has a portion 62 positioned below the elevator base 36 to sandwich the elevator base and the pallet base 54 therebetween under compression by means of a compression spring 64 and a threaded bolt member 66 having a nut 68 threaded on the bolt to adjust the resiliency of the spring 64 and thus the pressure (and resulting friction) between the pusher block 50, pallet base 54 and elevator base 36. A partially threaded screw 70 extends through the slot 58 in the elevator base 36 and an aligned slot 66 in the pallet base 54.

As best seen in FIGS. 7 and 8, an L-shaped locking lever generally designated 72, (which cooperates with the latch portions 56 of the pallet 52 as set forth below) is pivotally mounted on the pusher block 50 by means of a horizontal axis pin74. A cam plate 76 is mounted on the machine frame and is disposed below the elevator base 36 for engagement by the downwardly depending leg 72a of the locking lever 72, as seen in FIGS. 3 and 8. The horizontal leg 72b of the lever has a hook portion 72c for locking behind the latch portion 56 of the pallet, as seen in FIGS. 4 and 7.

For reasons to be described below, the pusher block 50 is fabricated of nylon or other plastic material so that there is less friction between the pusher block and the pallet base and elevator base than there is between the pallet base and the elevator base, both of which preferably are fabricated of metal.

The operation of the pallet and the related components will now be described. Referring to FIGS. 3 through 8, as the platform pusher 32 moves a package B onto the elevator A and into the sheet of film H the forward end of the package abuts against the front plate 501: of the pusher block 50, with the front plate 50a holding the film against the forward end of the package (see FIG. 3). Continued pushing by the platform pusher 32 causes the pusher block 50 to move relative to the pallet 52 to a position shown in FIG. 4 where the depending leg portion 72a of the locking lever slides off of the cam plate 76 to permit the hook portion 72c of the locking lever 72 to lock behind the latch portions 56 of the pallet 52. This relative movement of the pusher block 50, without causing movement of the pallet 72 relative to the elevator base 36 is permitted because, as mentioned above, lesser friction is afforded by the nylon or plastic material which comprises the pusher block. Further movement of the platform pusher 32 will move the package B completely onto the elevator base 36 and the package, in turn, moves the pallet and pusher block as a unit relative to the elevator base to a position shown in FIG. 5, with the right-hand end (as viewed in FIG. 5) of the pallet base 54 holding the film at the free end thereof against the underside of the package. The pallet base has a length (the right to left dimension in the drawings) approximately equal to the length of film initially wrapped under the package, at the free end of the film, whereby the pallet base never comes into contact with the underside of a package and thus the pallet base does not become sticky from water, meat juices, or meat and fat particles which might adhere to the underside of the packages.

The package elevator is then moved upwardly to permit the package to be moved from the elevator to the wrapping station F. Referring to FIGS. 6-8, the elevator pusher 51 is moved into engagement with the side of the pusher block 50 opposite the package B and continued movement of the pusher 51 moves the package, the pallet 72 and its related components from the position shown in FIG. 6 (with the package B still resting completely on top of the elevator base 36 and the pallet base 54) to a position shown in FIG. 7 with the package B partially moved from the elevator base toward the package wrapping station. During this movement, in the direction of arrow X (FIG. 6), the locking lever 72 is still in engagement with the latch portions 56 of the pallet 52 so that the pallet and the pusher block 50 move as a unit from the position shown in FIG. 6 to that shown in FIG. 7. At this point, the depending leg portion 72b of the locking lever 72 engages the cam plate 76 which causes the lever to pivot about pin 74 and move the hook portion 72c out of its locking position behind the latch portions 56 of the pallet. This permits the pusher block 50 (by reason of its lesser friction) to continue moving toward the wrapping station from the position shown in FIG. 7 to the position shown in FIG. 8 without similar movement of the pallet 52 relative to the elevator base. At the edge of the elevator base, the pusher block is positively stopped by an abutment 86 (FIG. 8). The package is thus moved off of the elevator and the pallet to the wrapping station F with the free end of the film H overlapped as seen in FIG. 8.

It can be seen that the pallet base 54 holds the free end of the film H against the underside of the package B when the package is moved across the elevator base 36 in the direction of arrow X from the position shown in FIG. 6 to that in FIG. 7,

thereby insuring that the free end of the film will not be torn away form the package as the package moves along the top of the elevator base. The pallet base does not become sticky because it does not contact the underside of the package.

We claim:

1. In an automatic wrapping machine which has package forming means extending along a path and with structure for preliminarily placing wrapping film from a supply roll around the package prior to the package entering said path, said structure including a transfer platform movable in a direction generally coplanar with the surface of the transfer platform between a package receiving position and a position remote therefrom, a package elevator movable between a lower position adjacent said transfer platform when the latter is in said remote position and an upper position at the level of said path, means for transferring a package from said transfer platform to the elevator in its lower position thereby moving the package into the film adjacent the free end of the film to cause preliminary wrapping of the film about the package, and means for transferring the package from the elevator into said path to complete the wrapping of the film about the package, the improvement comprising a package support member movably mounted on said elevator for receiving the package and having an abutment for engagement by the package, the package support member having a length approximately equal to a length of film initially wrapped under a package and not extending beyond the end of the length of the film whereby the support member does not come into contact with the underside of the package and whereby the film is disposed between the support member and package while the package is being transferred from the elevator into said path so that the film is positively carried by said package support member to insure a complete wrap of the film about the package.

2. In an automatic wrapping machine which has package forming means extending along a path and with structure for preliminarily placing wrapping film from a supply roll around the package prior to the package entering said path, said structure including a transfer platform movable in a direction generally coplanar with the surface of the transfer platform between a package receiving position and a position remote therefrom, a package elevator movable between a lower position adjacent said transfer platform when the latter is in said remote position and an upper position at the level of said path, means for transferring a package from said transfer platform to the elevator in its lower position thereby moving the package into the film adjacent the free end of the film to cause preliminary wrapping of the film about the package, and means for transferring the package from the elevator into said path to complete the wrapping of the film about the package, the improvement comprising a palletlike member mounted on said elevator for reciprocating movement relative to the elevator toward and away from said transfer platfonn and said path and on which rests at least the portion of said package over which the free end of the film is wrapped to prevent contact between the free end of the film and the elevator during relative movement therebetween and to hold the free end of the film against the package as the package is moved into the film from said transfer platform to said elevator and to move with the package as the package is transferred from the elevator into said path, and a package pusher member mounted on said pallet for reciprocating movement relative to the pallet and the elevator in the same direction as the reciprocating movement of the pallet relative to the elevator, said pusher member being fabricated of material to provide lesser friction between it and the pallet than between the pallet and the elevator whereby movement of the package from the transfer platform onto the elevator and the pallet against the friction member will cause the pusher member to move to a locking position on the pallet before the pallet is moved with the package and to permit the pusher member to move relative to the pallet to transfer the package from the pallet and the elevator into said path to complete the wrapping of the film about the package.

3. The automatic wrapping machine of claim 2 including a latch means to hold said pusher member in said locking position with a portion of the pallet underlying the package with the free end of the film between said pallet and the package.

4. The automatic wrapping machine of claim 3 including a cam member in the path of said latch means when the latch means is moved on the elevator toward said path to cause the latch means to become unlocked and to permit the pusher member to move relative to the pallet and push the package from the pallet into said path.

5. In an automatic wrapping machine, a package elevator movable between a package receiving position and a package discharg'e position, a package support member having a length approximately equal to a length of film initially wrapped under a package and not extending beyond the end of the length of film whereby the support member does not come into contact with the underside of the package, the support member being movably mounted on said elevator and having an abutment for engagement by a package, means for moving a package onto said package support member and into a length of film with the leading end of the film under the package, continued movement of said package causing said package to engage said abutment and move the package support member with the package, and means operative when the package elevator is in said package discharge position to move said package support member and package in a direction to move the package off the elevator whereby the film is disposed between the support member and package while the package is being transferred from the elevator so that the film is positively carried by said package support member to insure a complete wrap of the film about the package.

6. An automatic wrapping machine which has package forming means extending along a path and with structure for preliminarily placing wrapping film from a supply roll around the package prior to the package entering said path, said structure including a transfer platform movable in a direction generally coplanar with the surface of the transfer platform between a package receiving position and a position remote therefrom, a package elevator movable between a first position adjacent said transfer platform when the latter is in said remote position and a second position vertically spaced from said first position at the level of said path, means for transferring a package from said transfer platform to the elevator in said first position thereby moving the package into the film adjacent the free end of the film to cause preliminary wrapping of the film about the package, means for transferring the package from the elevator into said path to complete the wrapping of the film about the package, and a package support member movably mounted on said elevator for receiving the package and having an abutment for engagement by the package, the package support member having a length approximately equal to a length of film initially wrapped around a package and not extending beyond the end of the length of the film whereby the support member does not come into contact with the underside of the package and whereby the film is disposed between the support member and package while the package is being transferred from the elevator into said path so that the film is positively carried by said package support member to insure a complete wrap of the film about the package.

7. An automatic wrapping machine which has package forming means extending along a path and with structure for preliminarily placing wrapping film from a supply roll around the package prior to the package entering said path, said structure including a transfer platform movable in a direction generally coplanar with the surface of the transfer platform between a package receiving position and a position remote therefrom, a package elevator movable between a first position adjacent said transfer platform when the latter is in said remote position and a second position vertically spaced from said first position at the level of said path, means for transferring a package from said transfer platform to the elevator in saidfirst position thereby moving the package into the firm adjacent the free end of the film to cause preliminary wrapping of the film about the package, means for transferring the package from the elevator into said path to complete the wrapping of the film about the package, a palletlike member mounted on said elevator for reciprocating movement relative to the elevator toward and away from said transfer platform and said path and on which rests at least the portion of said package over which the free end of the film is wrapped to prevent contact between the free end of the film and the elevator during relative movement therebetween and to hold the free end of the film against the package as the package is moved into the film from said transfer platform to said elevator and to move with the package as the package is transferred from the elevator into said path, and a package pusher member mounted on said pallet for reciprocating movement relative to the pallet and the elevator in the same direction as the reciprocating movement of the pallet relative to the elevator, said pusher member being fabricated of material to provide lesser friction between it and the pallet than between the pallet and the elevator whereby movement of the package from the transfer platform onto the elevator and the pallet against the friction member will cause the pusher member to move to a locking position on the pallet before the pallet is moved with the package and to permit the pusher member to move relative to the pallet to transfer the package from the pallet and the elevator into said path to complete the wrapping of the film about the package.

8. The automatic wrapping machine of claim 7 including a latch means to hold said pusher member in said locking position with a portion of the pallet underlying the package with the free end of the film between said pallet and the package.

9. The automatic wrapping machine of claim 8 including a cam member in the path of said latch means when the latch means is moved on the elevator toward said path to cause the latch means to become unlocked and to permit the pusher member to move relative to the pallet and push the package from the pallet into said path.

Claims

2. In an automatic wrapping machine which has package forming means extending along a path and with structure for preliminarily placing wrapping film from a supply roll around the package prior to the package entering said path, said structure including a transfer platform movable in a direction generally coplanar with the surface of the transfer platform between a package receiving position and a position remote therefrom, a package elevator movable between a lower position adjacent said transfer platform when the latter is in said remote position and an upper position at the level of said path, means for transferring a package from said transfer platform to the elevator in its lower position thereby moving the package into the film adjacent the free end of the film to cause preliminary wrapping of the film about the package, and means for transferring the package from the elevator into said path to complete the wrapping of the film about the package, the improvement comprising a palletlike member mounted on said elevator for reciprocating movement relative to the elevator toward and away from said transfer platform and said path and on which rests at least the portion of said package over which the free end of the film is wrapped to prevent contact between the free end of the film and the elevator during relative movement therebetween and to hold the free end of the film against the package as the package is moved into the film from said transfer platform to said elevator and to move with the package as the package is transferred from the elevator into said path, and a package pusher member mounted on said pallet for reciprocating movement relative to the pallet and the elevator in the same direction as the reciprocating movement of the pallet relative to the elevator, said pusher member being fabricated of material to provide lesser friction between it and the pallet than between the pallet and the elevator whereby movement of the package from the transfer platform onto the elevator and the pallet against the friction member will cause the pusher member to move to a locking position on the pallet before the pallet is moved with the package and to permit the pusher member to move relative to the pallet to transfer the package from the pallet and the elevator into said path to complete the wrapping of the film about the package.

5. In an automatic wrapping machine, a package elevator movable between a package receiving position and a package discharge position, a package support member having a length approximately equal to a length of film initially wrapped under a package and not extending beyond the end of the length of film whereby the support member does not come into contact with the underside of the package, the support member being movably mounted On said elevator and having an abutment for engagement by a package, means for moving a package onto said package support member and into a length of film with the leading end of the film under the package, continued movement of said package causing said package to engage said abutment and move the package support member with the package, and means operative when the package elevator is in said package discharge position to move said package support member and package in a direction to move the package off the elevator whereby the film is disposed between the support member and package while the package is being transferred from the elevator so that the film is positively carried by said package support member to insure a complete wrap of the film about the package.

7. An automatic wrapping machine which has package forming means extending along a path and with structure for preliminarily placing wrapping film from a supply roll around the package prior to the package entering said path, said structure including a transfer platform movable in a direction generally coplanar with the surface of the transfer platform between a package receiving position and a position remote therefrom, a package elevator movable between a first position adjacent said transfer platform when the latter is in said remote position and a second position vertically spaced from said first position at the level of said path, means for transferring a package from said transfer platform to the elevator in said first position thereby moving the package into the firm adjacent the free end of the film to cause preliminary wrapping of the film about the package, means for transferring the package from the elevator into said path to complete the wrapping of the film about the package, a palletlike member mounted on said elevator for reciprocating movement relative to the elevator toward and away from said transfer platform and said path and on which rests at least the portion of said package over which the free end of the film is wrapped to prevent contact between the free end of the film and the elevator during relative movement therebetween and to hold the free end of the film against the package as the package is moved into the film from said transfer platform to said elevator and to move with the package as the package is transferred from the elevator into Said path, and a package pusher member mounted on said pallet for reciprocating movement relative to the pallet and the elevator in the same direction as the reciprocating movement of the pallet relative to the elevator, said pusher member being fabricated of material to provide lesser friction between it and the pallet than between the pallet and the elevator whereby movement of the package from the transfer platform onto the elevator and the pallet against the friction member will cause the pusher member to move to a locking position on the pallet before the pallet is moved with the package and to permit the pusher member to move relative to the pallet to transfer the package from the pallet and the elevator into said path to complete the wrapping of the film about the package.