US2973610A

US2973610A - Bag filling machine

Info

Publication number: US2973610A
Application number: US744975A
Authority: US
Inventors: Ralph S Randall
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-06-27
Filing date: 1958-06-27
Publication date: 1961-03-07
Anticipated expiration: 1978-03-07

Description

March 7, 1961 R. s. RANDALL BAG FILLING MACHINE Filed June 27, 1958 4 Sheets-Sheet 1 m1n-mnnnnnnnnnnnnnnnnnnnrv EII3 z INV ENT OR. Ralph S. Randall A TTORNE Y March 7, 1961 5, RANDALL 2,973,610

BAG FILLING MACHINE Filed June 27, 1958 4 Sheets-Sheet 2 Ralph S. Ronda/l ATTORNEY March 7, 1961 s, RANDALL 2,973,610

BAG FILLING MACHINE Filed June 27, 1958 4 Sheets-Sheet 3 M W I E IE... B

INV EN TOR. Ralph S. Randall ATTORNEY March 7, 1961 R. s. RANDALL 2,973,610

BAG FILLING MACHINE Filed June 27, 1958 4 Sheets-Sheet 4 EII3 EI J 27 /83 /6 I84 /67 l INVENT OR. Ralph S. Randall A TTORNE Y I tCd tate Pgtfi BAG FILLING MACHINE Ralph s. Randall, 33 20th St., San Francisco, Calif. Filed June 27', 1958, Ser. No. 744,915

18-Claims. c1. se -18s This invention relates to bagging and packaging machinery, and more particularly to machines for inserting food products such as sliced meats and the like into plastic bags which are then sealed and marketed. V

Insertion of the food product into the plastic bags and sealing of thelatter is commonly done by hand. Because of high labor cost and the enormous number of packages required, such methods are unsatisfactory and mechanization of the operation is desirable.

Machinery for this purpose. must be rapid, while at the same time precise to insure correct packaging and to prevent costly tie-ups in production The equipment must be sturdy and-capable of high-speed operation over long periods of time and must conform to the sanitation standards of the food industry.

It is, therefore, an object of the present invention to provide a baggingmachine which will function in a foolproof manner, at high speed, and over a long 'period of time. 1

Another object of my invention is to provide a bagging machine adapted for hand loading or for automatic loading with equal efiiciency.

A further object of the invention is the provision in a bagging machine, of a novel bag supply device which will automatically and. synchronously present a single bag to a bag receiving station with its end open and in position for insertion of the product. 5

A still further object of my invention is to provide a timed rocking and reciprocating action providing troublefree insertion of the product into the bag and ejection of the filled bag from the machine. V

vAnother object of the invention is to providea bagging machine of thecharacter described in which all movement and controls are mechanical in nature and notdependent upon electrical equipment.

. Yet another object of the invention is' to providea bag magazine which will automatically advance .the stack of bags in response to demand to maintain the topmost bag. of the. stack in .a

desired plane andat a desired height.

A further object of my invention is to provide drive for a bagging machine of thecharacterdescribed which Figure 1, wlthportions brokenaway and shown in section to reveal internal mechanism; r

Figure 3 is an enlarged longitudinal sectional view of a 2,973,610 Patented Mar. 7, 1961 bag filling portion of the machine and istaken substantially on the plane of the line 3-3 of Figure 1;

Figure 4 is a fragmentary detail view of a portion of the apparatus shown in Figure 3, but in another position;

Figure 5. is a schematic view of a hydraulic drive, system forming part of the bagging machine;

Figure 6 is a cross-sectional deta.l View on an enlarged scale of a hydraulic motor forming part'of the hydraulic drive: system of Figure 5; s g i I Figure 7 is an enlarged perspective view of a bag pickup device forming part of the bagging. machine;

Figure 8 is a plan sectional view of an advancing mechanism for the bag magazine and is taken substantially on the plane of line 3-8 of Figure 2;

Figure 9 is a schematic view of a cam operated valve system forming part of the control for the drive mechanism of the bagging machine;

Figure ii) is an enlarged plan view, partially in section,

.of a typical valve employed in the system of Figure 9;

and

Figure 11 is a perspective view of a valve member forming part of the valve of Figure 10.

The bagging machine, as illustrated in the drawings, in cludes a platform 11 for supporting the product 12 to be bagged and finger means 13 at the opposite sides of the platform formed for gripping the unsealed end of a bag 14 adjacent to its sides and spreading it open, the finger means 13 being mounted for reciprocation along the sides of the platform if so as to draw the bag 14 into enveloping relation around the platform and the product 12 thereon.

Means to is also provided for displacing the bagged product from the platform as soon as the product is inserted in the bag and the bag is released by the finger means 13. 1

Bags 14 are contained in a stack in a bag machine 17 an'dare removed fromthe stack by a transferdevice 18 and presented open end foremost to the finger means 13.

As here shown, the bagging machine includes a frame 19 supporting the various'components and formed of elongated. plates 21 supported on vertical legs 22. The finger means I15 and the platform 11 are carried on a sub-frame 23, for vertical movement toward and away fromframe E9. The platform 11 is affixed to the subframe and reciprocates therewith between the position illustrated in Figure 2 and the down position shown in Figure 3 and indicated by the phantom lines of Figure 2.

When in its down position, the platform 11 is aligned with the open hag presented by the transfer device 18, and when in its up'position is elevated so that a filled bag ejected from the platform will not strikethe transfer device. i [To provide for the vertical movement of the platform 11, the sub frame is pivoted on a pin 24 carried in an upward extension of'the frame f9. Rocking motion of the sub-frame 23 ahoutpln Z4 is provided by an eccentric 26 secured to the sub-frame and to a drive shaft 27 forming part of drive means 28, so that one revolution of the shaft will move'the platform from up to down position and back to up position.

Reciprocation of the finger means 13 along the sides of the platform 11 is effected by the same drive means 28. The finger means 13 are carried at the forward end of a carriage 31 which is mounted for endwise reciprocation upon rollers 32 journaled on the sub-frame 23.

A crank 33, on drive shaft 27, is connected to the rear end of the carriage 31 by means of a link 34, so that one rotation of the drive shaft 27 will move the finger means 13 from the rear ofthe platform 11 to its for; ward edge and back to the rear (the position shown in Figures 1 and 2), in a synchronism with the rocking motion imparted to the sub-frame 23 by the eccentric 26.

The finger means 13 is 'best illustrated in Figures 3 and 4 and includes upper and

lower finger elements

36 and 37 which are vertically movable toward and away from each other. Preferably, the finger elements 36 .and 37 are pivoted together upon a pin 38 and are urged apart by a spring 39 compressed between element 36 and a boss 41 formed on element 37. An adjustable eccentric stop 40 on element 36 will contact boss 41 to limit the opening, if no bag is present.

.The forward ends of the

finger elements

36 and 37 are tapered to a point for easy entry of the finger elements into the open end 42 of a bag 14 as they approach the bag receiving station, see Figure 3. The finger elements are urged together as they approach this point by cam means which include a roller 43 journaled at the end of an arm 44 extending from the upper finger element 36. As the finger elements approach their forward limit of travel, the roller 43 engages and is displaced upward by a cam plate 46 carried by the frame 19 of the machine. This urges the finger elements together in time to enter the open end 42 of the bag 14.

Gripping means 47 is provided on one of the finger elements preferably element 36, which is operable to grip the bag 14 during movement of the finger means 13 to the rear. As here shown, this gripping means consists of a gripping member 48 pivoted on finger element 36 by a pin 49 and having a distal end 51 movable toward the finger element for gripping the bag 14 therebetween in the manner shown in Figures 3 and 4. A rubber insert 52 may be mounted in the end 51 to provide a non-slip gripping action.

The bag 14 is released by the gripping means 47 as the finger means 13 reaches its rearmost position so that the bag may be pushed from the platform 11 by the means 16. Such release is effected by contact of a roller 53 secured to a bent arm 54 attached to member 48, with an inclined cam plate 56 mounted on sub-frame 23. The

parts are formed and arranged so that this contact willurge the gripper member 48 upwardly away from the finger element 36 against the action of a spring 57 which tends to urge the gripper closed.

To hold the gripping means 47 in open position during travel of the finger means 13 back to the forward position of Figure 3, a cocking device 58 is provided. This device consists of an arm 59 pivoted to finger eleinent 36 on a pin 61 and having, at its distal end. a small roller 62 engageable with a notch 63 formed in the edge of the gripper member 48. When roller 62 is in the notch 63, the gripping member 48 will be held away from the finger element 36 in the manner shown in Figure 2.

Release ofthe cocking device 58 is accomplished by a roller 64 on an arm 66 attached to arm 59. The roller 64 engages a cam plate 67, carried by frame 19, as the finger means approaches its forward position. This urges the small roller 62 downwardly out of the notch 63, releasing the gripper member 48 which is then snapped downwardly against the bag by the spring 57.

The bag transfer device 18 incorporates a vacuum transfer means 68 consisting of a semi-cylindrical member 69 mounted for rolling movement across the topmost bag in the magazine 17. A plurality of ports 71 are formedalong one longitudinal edge of the member 69 to which vacuum is applied while the member is rolling. This action is best shown in Figure 3 of the drawings wherein it is seen that as the member 69 moves from right to left, the top bag 14 will be gripped by the vacuum ports 71 at its unsealed end and peeled from the stack to the position shown.

The peeling action is such that the bag 14 does not rub against the stack of bags. Such rubbing might tend to wrinkle up or displace certain types of bags and should be avoided. To prevent rubbing, the member 69 is mounted on a hollow shaft 72 which is supported on a pair of pinion gears 73 located at opposite sides of the magazine 17 and meshed with supporting rack gears 74. The pitch radius of the pinion gears 73 is equal to the distance from the center of shaft 72 to the surface of member 69 adjacent the ports 71.

Also, the member 69 is relieved, that is the distance from the surface to the center of the shaft 72 becomes less proceeding around. the periphery from the ports 71. This is here accomplished by making the member 69 cylindrical in form, but non-concentric with the shaft 72. As the member 69 moves from right to left, its surface will recede from the top of the stack of bags, permitting the bag 14 to movefreely to the relative position shown in Figure 3.

As an important feature of the present invention, the member 69 is formed to partially open the unsealed end 42 of the bag as it is presented at the bag receiving station for engagement by the finger means 13. This is accomplished by depressing the surface of the member 69 at the ports 71 in such a manner that the edge of the bag contacting the ports will be distorted sufficiently to cause the other edge to move away. Figure 7 of the drawings illustrates this construction.

Note that the depressed areas 76 terminate short of the ends of the member 69, so as to cause the bag end 42 to assume the position indicated in phantom lines. An air blast means 75 may be provided to supplement this opening action, if desired.

As shown in Figure 3, the ports 71 communicate with shallow depressions, having radius corners, which lead toward the front edge of the bag. The purpose of these depressions is to provide relatively large gripping surfaces for the vacuum to hold the bag without pulling it into the ports. A suitable longitudinal passage 77 and radial passages 78 communicate the ports 71 with the interior of the hollow shaft 72, which is, in turn, connected by hose 79 with a source of vacuum. The rolling motion of the transfer device in time with the rocking of the sub-frame 23 is effected by means of a crank 80 connecting the shaft 27 to shaft 72.

Means is provided for advancing the bags in the magazine 17 so that the topmost bag on the stack is always in position for picking up by the transfer device. This means includes a plate 81 underlying the stack of bags and supported on a screw means 82 to raise the plate a suitable distance to compensate as bags are removed from the top of the stack.

Because the bags are often slightly thicker at their bottom or sealed end than at the top or unsealed end, the plate 81 is pivoted on the screw means 82 so that it may assume the correct angle to make the top of the stack level, see Figure 2.

The screw means 82 consists of a vertical threaded shaft 83 outside of the magazine 17, and a follower 84 threadedly engaged with the shaft and extending through a slot in the magazine wall to a position underlying plate 81. Rotation of the threaded shaft 83 will cause the follower 84 and the plate 81 to'rise.

Such rotation is here effected by a ratchet device 86, shown in Figure 8, which consists of a ratchet gear 87 secured to shaft 83 and a link 88 carrying a pawl 89 journalled on the same shaft. Advancement of the pawl 89 to rotate the shaft 83 is effected by an air cylinder 91 pivotally secured to the frame 19 of the bagging machine.

Energizing of cylinder 91 to raise the bags is controlled by a spool valve 92 mounted on frame 19 just below one of the rack gears 74 which support the transfer device 18. The rack gears are carried on a frame 93 which is pivoted at 94 to the main frame 19 so that the height of the right end of the frame 93, as viewed in Figure 2, will depend upon the height of the right hand side of the stack of bags, due to, the weight of the transfer device cylinder to retract for the next stroke.

The height of the left hand side=of the stack of bags-is Controlled separately by an air cylinder 101 mounted on thefscrew follower S4'and bearing against the-undersideof the plate 81. Air is supplied to the cylinderrltll by aspindle valve 102 mounted on the bag magazine- 17 i and having a feeler 103 resting on top of the'stack (see Figure 3).

If the stack rises too high, the valve-102 vents'the cyl-- inder 10-1 to atmosphere through a restricted orifice, and if the stack istoo low, the valve suppliesair to it from a supply conduit 104- The valve 102 is in more or less constant operation, while the machine is in operation hunting the correct level by alternately supplying air to and venting-air from the cylinder 101'.

The drive means 28 for the bagging machine-is designed to rotate and halt the main drive shaft 27 at the. correct position by purely mechanical action. This is accomplished by a; hydraulic drive system 106 which is illustrated schematically in Figure of the drawings.

Included in the system 106 is a positive displacement hydraulic pump 107 connected through a filter 108 to a fiuid reservoir 109*by supply and return conduits 111 and 112. The conduit 112 is split and one branch 113- communicates with a positive displacement hydraulic motor 114 which drives the-main shaft 27' through gearing 1-16. The other branch 1-17 of the conduit-112 communicates-with a valve 118. The dischargeside of the motor 114 also communicates with valve 118- through con-- duit 119.

Thevalve 118 isofany suitable lineal-operating threeway type and in one terminal position will connect the' motor 114 to the reservoir through conduit 121, and in the other terminal position, will connect-the'branch' 117 to the reservoir to by-pass the motor and halt the shaft'27.

The present machine goes through its cycle rapidly and should halt at the same rest position each time. Because of the frequency; of operation in the order of one cycle per second, ordinary c1utch-brake combinations are not suitable.

The unit muststop positively and start quickly and should not be subject to undue wear during repeatedoperation. Moreover, it is desirable tobe able tocontrol the.

speed of the motor which turns the shaft-27 in order' to control thejspeed atlwhich-the bagging machine operates. It .is desired to 'eliminate electrical components as far as: possible in order to reduce shock hazardandto providepositive mechanical action To [this end," ,the" hy-; draulic drive system 106 incorporatesanovel mechanically controlled f meansforstarting: and stopping'thef machinef,

'In accordance with the presentfinvention, the motor 11:41 will -lockthe shaft inafiked position when theval v e 118i opens branch -1 17 to the reservoir and closesoff conduit 11% Apositive' displacement vaiie' type-motor, shown in- Figure 6, is used for this purpose.- Thesemotors have sliding vanes 131 set in a hub 132 mounted eccen'tri'cally. in a-sl ightly larger bore 133 formed in the motor. housing 134. Springs 136 urge thefvanes'outwardlysothathydraulic fluid'un'der pressure; in thein-let, 137'," will press against the vanes and rotate the motor asitp'assesthrough' the crescent-shapedspace138 to theoutlet'139.

Fluid pressure on the vanes '131-is balanced so'thatithej springs-136 can hold the edges of'thevanes against the wall of the bore133i- This is accomplished by small pas-1 sages 141 formed in=the hub 132"'alongside ithe -vaneson" the upstream side thereof; and communicating the" space. 138 with the -vane-slots =interi orly of the" inner "edges of the'vanes; With this constructiomhuidpressure in" space 138 will be counter-balanced by fluid pressure at the springs 136, so that the vanes will be displaced outwardly by the springs.

This form of vane motor will not provide a positive lock for the shaft 27 because it cannot equalize fluid pressures on bothsides of the vanes 13150 as to resist rotation in both directions. I

The vane motor 114, shown in Figure 6, providesfor' equalizing the pressure'on'alternate vanes from one direction and on the remaining vanes from the other di rection. This is accomplished by forming passages 141a on the downstream side of every other vane. It is noted that the space between the inlet and

outlet ports

137 and 139 must exceed the. spacing betweenthe alternate vanes for the vane motor 114 to act as a brake when vacuum isv present in a conduit 154.

Vacuum is applied in the system by a suitable vacuum pump 156 mounted on the frame 19 of the bagging machine, see Figure 2. This vacuum is supplied to the vacuum cylinder 151 through a starting valve 157 which is shown in Figures 1, 2 and 9 of the drawings.

The operation of my bagging machine is controlled by

cams

161, 162 and 163, mounted on the shaft 27, which. operates the mechanism in synchronism, so that the various movements take place in the correct sequence. These cams and their relation to each other and to their associated valves are best shown in Figure 9 of the drawings'. v

Cam 162 is formed to actuate a valve 164 to connect the vacuum pump 156 to the vacuum transfer hose 79 and to the starting valve 157 when the machine is at the rest period illustrated in Figure 2, and while the vacuum transfer device 18 is moving a bag to the bag receiving station. Note that the vacuum to hose 79, and to valve 157 is supplied by the same conduit. If no bag is present at-the ports 71 of transfer member 69, not enough vacuum will be available to start the machine.

Cam 1 63 is formed to actuate a shut-off valve 166 which is connected to the valve 152 by conduit 167. When the machine reaches its rest position, the cam 163 causes shut-off valve 166 to connect the conduit 167 to the atmosphere. ,This dumps the air from the cylinder 15'1 actuating the valve 118 to its terminal position to shut off fluid-flow through thevane motor 114 and halt the machine.

1 When starting valve 157 is actuated to actuate the valve 152"and supply air to the cylinder 151, the cam 163 reverses the valve 166 and connects the conduit 167 to an air supply conduit 168. .This supplies air tothe cylinder 151 during the rest of the cycle after the starting valv 157is no longer open.

Means 16 is provided for displacing the bagged product from the platform 11 as soon as it is released by the finger means 13 and just before the machine reaches its,

rest! position. This means consists of an air cylinder 171: having ,an extension 172 secured to its piston rod which terminates in a pusher plate 173. When air is.

supplied to the cylinder 171, the plate 173 advances across charged the package.

174 to supply air to the cylinder when'the shaft 27 reaches the platform pushing the bagged product in.

It is desirable to push the bagged product with controlled speed from the platform, depending upon the natureof the product, and then to return the plate 173 as quickly as possible to retracted position after it has dis- The cam 161 operates a valve which. is especially suitable, is shown in Figures 10" and 11 of'the drawings. Such valve includes a" bong 1&1"

having a chamber-182 inwhich the valvemember 183 is reciprocated by member 184. Formed in the valve body are

ports

186, 187, 188 and 189. The port 186 is connected to a source of airunder pressure. The valve member 183 is formed with a groove 185 in its face which confronts the ports and is movable between first and second terminal positions. 7 f

In the first terminal position, the groove 185

interconnects ports

187 and 188 and uncovers port 189 for communication with air supply port 186 which is never covered by the valve member 183. In the second terminal position,

ports

188 and 189 are connected by groove 185 while port 187, is uncovered to receive air from port 186. Normally,

ports

187 and 189 are connected to opposite ends of an air actuated cylinder and vport 188 is vented to atmosphere. Of course, the connections may be varied and the valve can be used with vacuum or hydraulic fluid where desired.

The bagging machine of the present invention may be readily adapted for use with bags and products of various sizes. For this purpose the platform 11, the vacuum transfer member 69, and the finger means 13 are preferably split longitudinally of the machine into two units which may be spread apart or brought together, as desired. For instance, the

finger elements

36 and 37 are here pivoted on block members 191 which have a wedgeshaped tongue 192 slidably engageable in a groove 193 formed in the end of the sub-frame 23 and are held in position by manually operated screws.

In operation, the product 12 to be bagged is placed on the platform 11. This may be done manually, or by any suitable feed mechanism, not shown. 157 is then actuated by pressing down on the member 196. This starts the machine which swings the platform down from the position shown in Figure 2 to the bag receiving position indicated in phantom lines.

At the same time, the finger means 13 advance to the position shown in Figure 3 where they are inserted in the open end 42 of a bag 14 which has been peeled from the stack in the bag magazine 17 and presented by the transfer device 18.

At this point, the cocking mechanism 58 releases the gripping members 48 causing them to grip the upper edge of the bag. The finger means 13 then travel toward the rear of the platform, opening up and spreading apart the bag as shown in Figure 4 as they proceed. Therbag is thus drawn into enveloping relation around the platform and the product thereon.

i As. the machine approaches the resti position of Figure 2, the gripping members 4am opened and cocked by the cam 56, thus releasing the bag. At this point, the air cylinder 171 suddenly displaces the plate 173 across the platform 11, pushing the product and enveloping bag therefrom. By this time, the platform is. again elevated above the transfer device 18. The bagged product may then slide down a chute 197 or be received on a suitable conveyor (not shown) for transporting to a packing station.

Iclaim:

l. A product bagging machine comprising a platform for supporting the product to be bagged, finger means at opposite sides of said platformformed for releasably gripping the unsealed end of a bag adjacent to its sides and spreading it open, said finger means being reciprocable along the sides of said platform so as to draw said bag into enveloping relation around said platform and the product thereon, a magazine adaptedto contain a stack of bags, and a transfer device adapted to remove. the topmost bag from said stack with its unsealed end. presented toward said finger means for gripping thereby.

2. A product bagging machine comprising a platform for supporting the product to be bagged, finger means mounted for reciprocation along the opposite sides of said platform between a forward bag receiving station at one end of said platform and a-rearward bag releasing station at the other end of said platform, said finger means being formed for releasably gripping the unsealed end of the bag at said bag receiving station and spreading it open upon movement toward said bag releasing station so as to draw said bag into enveloping relation around said platform and the product thereon, a magazine adapted to contain a stack of bags, vacuum transfer means formed to remove the topmost bag from said stack and present its unsealed end to said finger means when the latter is at said bag receiving station, and means for displacing the bagged product from said platform after said finger means have reached said bag releasing station and released said bag.

3. A product bagging machine comprising a frame, a

subframe having a platform for supporting the product The starting valve to be bagged mounted for vertical movement on said frame, finger means mounted for reciprocation along the opposite sides of Said platform between a forward bag receiving station at one end of said platform and a rearward bag releasing station at the other end of said platform, said finger means being formed for releasably gripping the unsealed end of a bag at said bag receiving station and spreading it open upon movement toward said bag releasing station so as to draw said bag into enveloping relation around said platform and the product thereon, drive means for effecting said vertical movement of said platform and said reciprocation of said finger means in synchronization whereby said platform will be in down position when said finger means are at said forward bag receiving station and said platform will be in up position when said finger means are at said rearward bag releasing station, a magazine adapted to contain a stack of bags, vacuum transfer means formed to remove the topmost bag from said stack and present its unsealed end to said finger means when the latter are at said bag receiving station.

4. A product bagging machine as described in claim 3 wherein said drive means includes a driven shaft, and an eccentric on said shaft connected to said subframe for moving the latter from said up to said down and back t; sfaid up positions upon one complete revolution of said s a t. a

. 5. A product bagging machine as described in claim 4 wherein said drive means'also includes a crank formed on said shaft, and a link connected between said crank and said finger means for reciprocating the latter from said rearward to said forward and back to rearward stations upon one complete revolution of said shaft.

6. A product bagging machine as described in claim 5 wherein said drive means includes a positive displacement hydraulic pump, a reservoir for hydraulic fluid, supply and return conduits connecting said pump and reservoir to provide a closed recirculating system, a constant speed motor driving said pump, a hydraulic motor in said return conduit and having an operative connection to said shaft for driving the latter while fluid is circulated through said hydraulic motor, a by-pass conduit connected to said return conduit between said pump and said hydrau- 11c motor, and valve means in said return conduit operable between terminal positions for selectively connecting said hydraulic motor and said bypass conduit to said reservoir whereby said hydraulic motor will rotate said shaft in one terminal position of said valve means and will act as a brake to halt said shaft when said valve means is moved to the other of said terminal positions.

7. A product bagging machine comprising a frame, a subframe pivotally mounted for rocking movement above the said frame, a platform for supporting the product to be bagged mounted at one end of said subframe for vertical movement relative to said frame, a carriage mounted for reciprocation longitudinally of said subframe, finger means mounted on said carriage for movement therewith along the opposite sides of said platform between aforward bag receiving station at one end of.

, 9 aid p atform, andia rearward asre as g tatiqn'at the, h r n of aid p rm,fsaid-finger ntieans."b in -v formed for releasably gripping the unsealede'ndof a bag.

atsaid bag receiving station and spreading it open upon movement toward said bag' releasing station 7 so. as to drawjsaidbag into envelopingrelationaround said platsaid stack and present itsunsealed end to said finger means.

when the latter are at said bag receiving station; and means for displacing the baggedproduct from said platform after said finger'means has reached said bagre: leasing station and released'said bag.

8. A product bagging machine comprising a platform, for supporting the product to 'be baggedyfinger means mounted for reciprocation along the opposite sides of. said'platform between a forward, bag receiving station. at one end of said platform and a, rearward bag releasing. station at the other end of said platform, said finger. means being formedffor releasably gripping the unsealed, end of a bag at said bag receiving station andsprea'dingit open upon movement toward saidbag releasing station. so as to draw said bag into enveloping relation around. said platform and the product thereon, a magazine adapted. to containa stack of bags, and a transfer means mounted over said magazinefa'nd having a row of suction openings. movable. from a first position engaging the upper surface, ofthe topmost of said bagsadjacent its unsealed'edge to afsecond position presenting said unsealed edge to's'ajid':

1 finger means at said bag receiving station.

'10 a sub-frame havingja platform frame, fingermeans mounted for reciprocation along the oppositefsides of said platform between aforward bag receiving station at one end of said platform and a rearward'bag releasing station at the-other end of said platform, said finger means 'beingformed for releasably gripping the unsealed en'dof a bag at saidbag receiving station and spreading it open upon movement towardsaid bag releasing station so'as jto draw said bag into enveloping relation around said platform and the product thereon, drivemeans for effecting said vertical movement of said platform and said reciprocation of said finger means in synchronization whereby said platform will be in down position when said finger means are'at said forward bagreceiving station and said platform will be in upposition when said finger means are at said rearward bag releasingstation, a magazine adapted to contain a stack of bags, a shaft mounted in horizontal relation above said stack of bags, a semi-cylindrical member mounted on said shaft and having a row of ports adjacent to one longitudinal edge, a pinion gear on said shaft, a rack gear engaged with said pinion gear and positioned for supporting said shaft and member for rolling movement of the latter across the uppermost of the bags, and means providing a vacuum at said ports at a terminal position of said member where said ports contact the upper side of an unsealed end of said uppermost v bag, said shaft and said gears being proportioned so as to 95A product bagging machine comprising a frame,.

a sub-frame having a platform for supporting the prod net to be. bagged. mounted for vertical movement on said framdfihge'r' means mounted for reciprocation along the opposite sides of said' platform between a forward row of suction openings movable from a first position engaging the upper surface of the topmost of said bags adjacent its unsealed edge to a second position presenting said unsealed edge to said finger means at said bag.

receiving station, drive means for effecting said vertical movement of said platform and said reciprocation of said finger means in synchronization whereby said platform will be in down position when said finger means are at said forward receiving station and said platform will be in up position when said finger means are at said rearward bag releasing station, said drive means being formed for effecting movement of said transfer means suction openings to said second position as said finger means approach said bag receiving station, and means for displacing the bagged product from said platform after said finger means has reached said bag releasing station and released said bag.

10. A product bagging machine as described in claim 70 9 wherein said means for displacing the bagged product from the platform is operated in synchronism with said drive means so as to displace said bagged product as said finger means reach said bag releasing station.

presentsaid unsealed end of the bag to said finger means at said bag receiving station when said member is at its, other terminal position.

12. In a bag'supply device having a magazine for containing a vertical stack of open end bags, a plate for snpporting said stack of bags mounted for vertical movement' in said magazine, screw means pivotally supporting said plateadjacent to the end thereof underlying the open ends of said bags, hydraulic means having'an ele-' ment positioned forengagement by the uppermost bag onsaid 'stack and being operative to advance said screw meansand raise the top of said stack to a predetermined height as bags are removed therefrom, a lifting means mounted on. said screw means and connected to said plate, and valve means having a feeler contacting'the upper surface of said uppermost bag remotefrom saidopen end and operable to energize said lifting means whereby.

the top of said stack will be maintained at a predetermined level as bags are. removed therefrom.

13. In a bagging machine having a platform for sup porting a product-to bebagged. and a device for supply! ingla bag with its open ends confronting. said platform,

bjagfilling means. comprising finger means mounted for;

'of a bag when at the forward end of said platform and for urging said finger elements apart to open said bag as said finger means moves toward the rear'end of said platform, gripping means operable to grip said bag during the movement of said finger means from said forward to said rearward ends of said platform whereby said bag will be drawn into enveloping relation around said platform and the product thereon, each of said upper and lower finger elements being provided with a pivotal connection, a spring urging said upper and lower finger elements apart, and said bag opening means including cam means on one of said finger elements responsive to said reciprocation of said finger means for urging said finger elements together against the action of said spring as the finger means approach the forward end of the platform.

14. In a bagging machine having a platform for sup- 1 1. A product bagging machine comprising a frame, porting a product to be bagged and a device for supplyforisupporting the 'prodpcti to be bagged mounted for vertical movementon said ing a bag with its open end confronting saidrplatfom, bag filling means comprising finger means mounted for reciprocation along the opposite sides of the platform and including upper and lower finger elements movable vertically toward and away from each other, means for reciprocating said finger means between the opposite ends of said platform, bag opening means for urging said finger elements together for insertion into the open end of a bag when at the forward end of said platform and for urging said finger elements apart to open said bag as said finger moves toward the rear end of said platform, gripping means operable to grip said bag during the movement of said finger means from said forward to said rearward ends of said platform whereby said bag will be drawn into enveloping relation around said platform and the product thereon, said gripping means including a member pivoted to one of said finger elements and having a distal end movable toward such finger element for gripping a bag therebetween, spring means urging said member toward said finger element, and cam means responsive to said reciprocation of said finger means for urging said member away from said finger element during movement of said finger means from the rear to the forward end of said platform.

15. In a bagging machine having a platform for supporting a product to be bagged and a device for supplying a bag with its open end confronting the platform, bag filling means comprising finger means mounted for reciprocation along the opposite sides of the platform and including upper and lower finger elements movable vertically toward and away from each other, means for reciprocating said finger means between the opposite ends of said platform, bag opening means for urging said finger elements together for insertion into the open end of a bag when at the forward end of said platform and for urging said finger elements apart to open said bag as said finger means moves toward the rear end of said platform, gripping means operable to grip said bag during the movement of said finger means from said forward to said rearward ends of said platform whereby said bag will be drawn into enveloping relation around said platform and the product thereon, said gripping means including a member pivoted to one of said finger elements and having a distal end movable toward such finger element for gripping a bag therebetween, spring means urging said member toward said finger element, and cam means responsive to said reciprocation of said finger means for urging said member away from said finger element during movement of said finger means from the rear to the forward end of the platform, said c'am means being formed to urge said member away from said finger element as said finger means approaches the rear end of said platform to thereby release said,

' rolling movement across said magazine in spaced parallel relation to the uppermost bag therein, a semi-cylindrical member formed with ports along one longitudinal edge adapted for connection to a source of vacuum for picking up the unsealed end of the uppermost bag, said semi-cylindrical member being mounted in non-concentric relation on said shaft with the longitudinal edge containing said ports furtherest from the shaft so as to relieve the periphery of said member from pressing against the stack of bags as it moves across the magazine whereby the uppermost bag will be supported in an are as its open end is brought up and over and with such bag out of sliding contact with the next bag in the stack.

17. In a bagging machine, a bag supply device as described in claim 16 and wherein said shaft is supported for said rolling movement across said magazine in spaced parallel relation to the uppermost bag upon pinion gears having a pitch diameter equal to the distance from the center of said shaft to said longitudinal edge containing said ports, said pinion gears being enmeshed with and running upon straight rack gears having their pitch line lying in the same plane as the upper surface of said uppermost bag. V v

18. In a bagging machine, a bag supply device as described in claim 16 and wherein said semi-cylindrical member is formed with a' depressed area at said ports terminating short of the ends of said member whereby the edge of the bag contacting said ports will be pulled down from the plane of the bag for effecting an opening of the bag across substantially its entire width.

References Cited in the file of this patent UNITED STATES PATENTS oirun Sept. 9, 1958