US3327618A

US3327618A - Package binding machines

Info

Publication number: US3327618A
Application number: US497575A
Authority: US
Inventors: Cook Peter Roy
Original assignee: Package Sealing Co Export Ltd
Current assignee: Package Sealing Co Export Ltd
Priority date: 1965-05-17
Filing date: 1965-05-17
Publication date: 1967-06-27
Anticipated expiration: 1984-06-27

Description

June 27, 1967 PETER ROY COOK PACKAGE BINDING MACHINES 6 Sheets-Sheet 1 Filed May 17, 1965 June 27, 1967 PETER ROY COOK 3,327,618

PACKAGE BINDING MACHINES Filed May 17, 1965 6 Sheets-Sheet 2 4/ 2/ 2m 2a {a 79.

ATTORNEYS June 27, 196 PETER ROY COOK PACKAGE BINDING MACHINES 6 Sheets-Sheet 3 Filed y 17, 1965 ATTORNEY5 June 1967 PETER ROY COOK 7 3,327,618

PACKAGE BINDING MACHINES e Sheet-Sheet 4 Filed May 17, 1965 I lit I ATTORNEYS June 1967 PETER ROY COOK PACKAGE BINDING MACHINES Filed May 17, 1965 6 Sheets-Sheet 5 L m gm m V J vw 10 A 7 76 June 27, 1967 PETER ROY COOK 3,327,613

PACKAGE BINDING MACHINES Filed May 17, 1965 e Sheets-Sheet 6 INVENTOR PETER ROY COOK sYigm zm/zwwzw ATTORNEYS United States Patent 3,327,618 PACKAGE BINDING MACHINES Peter Roy Cook, Kent, England, assignor to Package Sealing Company (Export) Limited, Maidenhead, Berkshire, England, a British company Filed May 17, 1965. Ser. No. 497,575 Claims. (Cl. 100-4) This application is a continuation-in-part of application Serial No. 236,881 filed November 13, 1962, and which issued as Patent No. 3,183,824 on May 18, 1965.

This invention is concerned with machines for binding packages with flexible metal binding material and of the kind comprising means for feeding the material endwise, a guide which receives the material and directs it to form a loop with overlapping ends, means for tightening the loop around a package, and a connecting device for i011!- ing the ends of the tightened loop.

Moreover, the invention is concerned with a machine of the above kind in which at least some of the machines components are powered or controlled by pneumatic means which operate in an automatic sequence including the loop-forming operation. This raises the problem of sensing when the free end of the material reaches or approaches its final position during the loop-forming operation, so that the automatic sequence can be stopped or continued.

According to the present invention the machine comprises a controlling air circuit which includes an air duct leading to a bleed port, the arrangement being such that as the free end of the material approaches its final position during the loop-forming operation it effects a change in flow conditions at the bleed port, and the machine also comprises means responsive to the ensuing pressure change in the air duct for at least terminating the feeding action of the feed means.

The pressure change in the air duct maybe a pressure rise or a pressure drop, according to whether the bleed port is opened or closed by the free end of the material.

The bleed port may be controlled by its own obturator which is positioned so as to be operated by the free end of the material as the latter approaches its final position. Movement of the obturator in response to actuation by the free end of the material may either open or close the bleed port.

Preferably, the bleed port is normally open and is closed by the free end of the material which itself acts as the obturator. One way of achieving this result is to provide a guide structure which contains the bleed port and which receives the free end of the material as the latter approaches its final position.

The guide structure preferably consists of two parts one of which is movable to open and close it, and the meeting faces of the two parts are formed with confronting grooves one of which, when the guide structure is closed, conducts the material into the aforesaid guide and the other of which contains the bleed port and receives the free end of the material as the latter approaches its final position.

Preferably the connecting device is a twister pinion and the binding material is flattened wire and in this case the guide structure consists of a stationary upper part formed with the groove containing the bleed port and a movable lower part formed with the other groove.

The guide structure is preferably opened and closed by an air cylinder and means are provided inlthe air circuit for causing this air cylinder to open the guide structure at the end of the twisting action of the twister pinion and for closing'it after the ejection of the tie.

The feeding means preferably comprises a driving roller, a bodily movable pressure roller and an air cylintier controlled by a pressure-responsive valve for bringing the pressure roller into wire-feeding relationship with the driving roller.

The machine according to the invention also includes other novel features which are set forth in the appended claims and which are exemplified in a specific embodiment described with reference to the accompanying drawings. In the drawings:

FIGURE 1 is a front elevation of a machine in accord. ance with the invention,

FIGURE 2 is a section through the twister pinion and associated parts in the binding plane,

FIGURE 3 is an enlargement of part of FIGURE 2,

FIGURE 4 is a diagram of the air circuit,

FIGURE 5 is a rear elevation of the machine,

FIGURE 6 is a section on the line 66 in FIGURE 1,

FIGURE 7 is a section on the line 7-7 in FIGURE 1,

FIGURE 8 is a section similar to FIGURE 7 but showing the guide ring in the open position.

The machine comprises a foundation plate 10 which carries the chief working components. This plate is mounted vertically on a frame (not shown) consisting of a base, two pillars at the sides of the plate and a cross beam connecting the tops of the pillars. The plate is secured to the frame by any suitable means.

The chief components mounted on the plate are a guide ring 11 which surrounds an aperture 12 for the package; a twister pinion gear box 13 which is located in a deep slot in the plate below the package aperture; a reversible feed 14 and an extra-tension device 15. An electric motor 16 for driving the reversible feed is also mounted on the plate.

A reel 17, carrying a coil of flattened wire, and a slack take-up device 18 are mounted in one corner of the frame.

The guide ring 11 is a metal bar bent into an approximate rectangle with rounded corners, a gap being left between the ends. The ring is disposed in front of the plate and its rear surface has a groove 11a in it which constitutes the loop-shaped part of the wires fiow path. The ring is movable into and out of contact with the plate by four double-acting air cylinders A which are fixed to the back of the plate and the piston rods 19a of which pass through holes in the plate to connect with lugs 19 attached to the ring. The ring is closed, that is to say held in contact with the foundation plate, during the loop-forming operation when the forward feed drives the free end of the wire round the ring. The ring is opened to permit reverse feed and the application of extra tension.

The twister pinion gear box is topped 'by anose plate- 20 which provides a support for the packages. The pinion 20a is mounted in the box on bored pivots 21 fixed to the underside of the nose. In the resting condition the slot in the twister pinion is horizontal and points forwards. When the pinion is operated to twist together the ends of the loop it performs three revolutions to apply the twist and a further fraction of a revolution to apply the overtwist, after which the pinion is turned back through the angle of overtwist to bring the slot into its resting position to allow ejection of the twist. This motion is accomplished by two double-acting air cylinders and two unidirectional driving mechanisms as follows.

The twister pinion is driven through an idler 22 by a gear wheel 23 which rotates on a transverse shaft 24 jour'nalled in the sides of the gear box, the speed ratio between the gear wheel and the pinion being 9:1 so that of gear wheel movement produces three revolutions of the pinion. The gear wheel is large enough to project through apertures in the front and rear walls of the gear box and it carries on its flanks two ratchet discs 25, 26.

28 which has two limbs terminating in hubs 29. These hubs are keyed to the shaft by two common keys which are covered in the middle by a sleeve 30 on which the gear wheel is mounted by a bush bearing. The outer end of the arm carries a double-toothed pawl 31 engaging with the edges of the two ratchet discs and forming unidirectional clutch means.

The shaft also carries a pinion 32 driven by a rack 33 which is attached to linearly reciprocable driving means formed by the piston rod of twist cylinder D. The arm is caused to drive the gear wheel through a little more than 120, by the upstroke of cylinder D and is recovered by the downstroke. The stroke of the twist cylinder is limited by an adjustable trip valve T which is arranged to reverse the upstroke of the twist cylinder. This sensing valve is operated by a cam 34 mounted on the shaft outside the boX. The sensing valve is adjustably mounted so that its position can be altered to increase or reduce the stroke of the twist cylinder, that is to say to increase or reduce the amount of overtwist.

When the gear wheel has been turnedfor twist and overtwist it must be returned through the angle of overtwist so as to bring the twister pinion into a position in which the tie can be ejected. The ejection position of the gear wheel is defined by a stop pawl 35 which is mounted on the front of the gear box in contact with the far side ratchet disc. The far side ratchet disc is driven back against this pawl by second unidirectional driving means comprising the overtwist return cylinder B. The stop pawl. is mounted on an eccentric for the purpose of allowing it tobe adjusted to compensate for wear of the gear teeth.

The stop pawl is mounted on two

vertical plates

36, 37 which are positioned on the front of the box on the far side of the aperture through which the gear wheel projects. These two plates are formed with identical slots 38 which are adapted to guide a striker pin 39 into and out of the recesses 27 in the far side ratchet disc. The striker pin is connected to the piston rod of overtwist return cylinder B by a link member 40 which runs between the plates. The pivot pin which connects the link member to the piston rod of cylinder B also runs in the slots. During the driving stroke of the overtwist return cylinder the striker pin is guided into that recess in the far side ratchet disc which is presented at the front of the gear box, engages the upper end of the recess and then pushes the disc back against the stop pawl. The driving stroke of the overtwist return cylinder is tripped by the trip valve T and so is performed during the downstroke of twist cylinder D.

The pawl on the driving arm operates the ejectors during the downstroke of twist cylinder D. The ejectors are two bars 41 which flank the twister pinion and slide backwards and forwards in guides beneath the nose plate. The rear ends of the ejectors are connected by a pivoted frame 42 which is biased to the rear by a spring and embraces a roller n the upper end of a lever 43 pivoted to the back of the box. The lower end of the lever carries another roller 44 which lies near the arc of movement of the pawl 31. During the upstroke of the twist cylinder D the pawl 31 is sunk in its notches and misses the roller 44. During the downstroke however the pawl rises onto the lands of the ratchetdiscs and its arc of movement intersects the resting position of roller 44.

The driving arm also carries a cam 45 which operates a trip valve U during the downstroke of the twist cylinder D. This trip valve carries a lever and pivoted tooth arrangement 46 which enables cam 45 to actuate the trip valve U on the downstroke but not on the upstroke of twist cylinder D. The trip valve U is arranged to continue the sequence of operations as will be described later.

The gear box also contains a holding gripper on the near side of thetwister pinion. The gripper comprises a body 47 which is arranged to slide up and down inside a tube 48.'The top of the body carries a head 49 which co-operates with the underside of the nose plate in gripping the free end of the loop of wire. The head is penetrated by a through bore 50'through which 'the wire between the twister pinion and the reversible feed extendsThe top portion of the grippers head therefore acts as a spacer which limits the twist on the near side of the twister pinion. The gripper is raised and lowered, to grip or release the wire, by a lever 51 which is pivoted inside the box and extends forwards, through slots in the tube, the grippers body and the front wall of the box to the outside, where it is connected by a connecting rod 52 to the piston rod of double-acting air cylinder E.

The tube carries a wire-severing knife 53' which slides against the head of the gripper. The bottom of the tube carries a roller 54 which is urged into contact with a cam 53a on the transverse shaft by a spring between the body of the gripper and the tubes bottom. The cam 53a is shaped to raise the knife above the far side and of the bore 50 in the holding grippers head just before the upstroke of the twist cylinder D is reversed. The wire is severed under tension.

On the far side of the twister pinion is a pseudo-gripper, so called. This consists of a body 57 able to slide up and down in bearings. The body is topped by a head v 58 which co-operates with the underside of the nose plate. The pseudo-gripper is raised and lowered by a lever 59 which is pivoted inside the box and extends forwards through slots in the body 57 and the front of the box to the outside, where it is connected by a connecting rod 60 to the double-acting air cylinder F.

The top of the head is inclined and is crossed by an open ended groove 61 which extends in the direction of wire movement. This groove is deeper at the near side end andits bottom at this end is rounded.

A second groove 62, which is open at the near side end only, is present in the nose plate. This upper groove 62 is exactly opposite to andexten-ds in the same direction as the lower groove.

During forward feed the pseudo-gripper is up and the holding gripper is down. The free end of the wire is fed from the holding gripper, through the twister pinion and the notches in the ejectors and into the groove 61 in the head of the pseudo-gripper. This groove directs the free end of the wire upwards into the ring. After going round the ring, the free end of the wire passes between the holding gripper and the nose plate, through the ejectors and twister pinion a second time and into the upper groove 62. The loop of wire thus formed lies in one plane and the overlapping portions thereof are in face-to-face relationship. The pseudo-gripper locates the overlapping portions of the wire on the far side of the twister pinion without gripping them and also limits the progress of the twist on that side.

The arrangement also includes a means for sensing when the free endof the wire approaches or arrives at its final position and for terminating the forward feed.

As shown in FIGURE 2 the nose plate on the far side is penetrated by an air duct 63 which communicates through a bleed port 63a with the upper groove 62. As. the free end of the wire approaches the pseudo-gripper for the second time air is being discharged through the bleed port. The entry of the free end of the wire into the upper groove stops this discharge of air and causes a pressure rise in air duct 63. This pressure rise actuates a valve controlling the forward feed and thereby terminates forward feed as will be explained later. The upper groove 62 includes a stop 65 for the free end of the wire.

The head of the pseudo-gripper and the adjacent portion of the nose plate in fact constitute the lower and upper parts of a guide structure which elfects the guiding of the free end of the wire into a desired final position, locates the overlapping portions of the wire on the far side against relative rotation during the twist and limits the progress of the twist on the far side. Furthermore this guide structure is openable to permit ejection.

In the arrangement described the free end of the wire itself acts as the obturator of the bleed port but, although this is the preferred arrangement, it is not necessary that it should do so and alternative arrangement may be found to function satisfactorily.

The reversible feed comprises forward and reverse driving

rollers

66 and 67 the shafts of which are geared together and mounted in a carrier plate 68 bodily movable about a pivot 69 on a fixed bracket depending from the foundation plate. Above the driving rollers are two pressure rollers 70 and 71 which are mounted in a tilting holder 72. This holder has two operative positions and a neutral position. In either of the operative positions one of the pressure rollers is down to engage the wire with the associated driving roller. In the neutral position both pressure rollers are out of action. The holder is adapted to be tilted in a clockwise direction by the piston rod of reverse-feed air cylinder G and in an anticlockwise direction by the piston rod of forward-feed air cylinder H. Each of these air cylinders contains a piston which is urged upwards by a spring and is adapted to be urged downwards by air pressure. The shaft of the forward-feed drive roller is continually driven through a friction clutch and a belt and pulley by an electric motor 16 which is mounted on the foundation plate.

The carrier plate 68 on which the reversible feed is mounted lies adjacent to a trip valve V mounted on the back of the foundation plate. The plate 68 is normally biassed away from this trip valve in a direction opposite to the reaction of the wire on the reverse-feed rollers by a spring 74.

' During forward feed compressed air is admitted to the top of forward-feed cylinder H and the forward-feed pressure roller 70 is held down to grip the wire between itself and the associated driving roller. The wire is consequently fed towards the binding plane. Between the reversible feed and the holding gripper, the wire is conducted by a grooved bar 75 which is fixed to the foundation plate. The compressed air is cut off from the cylinder H when the free end of the wire closes the bleed port in the nose plate.

During reverse-feed compressed air is admitted to the top of reverse-feed cylinder G and reverse-feed pressure roller 71 is held down. Reverse feed continues until the tension in the wire is equal to the pull of the reversefeed rollers, whereupon the reverse-feed rollers climb the wire, shifting the plate 68 against the action of its spring. Consequently, the trip valve V is operated. The trip valve V is arranged to trip the operation of the extra-tension device and disengage the reverse feed drive. The controlling air circuit is so arranged that the air supply to the reverse feed cylinder G is not cut oil until after the extratension device has been actuated.

The extra-tension device consists of a lever 76 which is pivoted to the foundation plate. The lever is in two parts pivoted together at 79. The upper part is slotted at its lower end and the slot contains the fixed jaw 80 and the pivoted jaw 81 of an extra-tension gripper. The lower part of the lever is also slotted, the slot receiving the lower end of the upper part and containing a roller 82 which engages a cam surface on the pivoted jaw of the extra-tension gripper. The gripper is normally held open by a spring 83. The lower part of the lever is connected by a connecting rod to the piston rod of d0uble-acting air cylinder C. The cylinder C is pivoted to the frame of the machine.

When the extra-tension cylinder C is tripped by trip valve V its piston rod extends and drives the lower part of the extra-tension lever away from the reversible feed. This movement causes the roller 82 to close the extratension gripper, after which the whole lever moves away from the reversible feed pulling the wire with it. Since the extra tension device is applied just before the release of the reverse feed there is no loss of tension in the wire. The final tension in the wire is determined by the air pressure in cylinder C. The lower part of the extra-tension lever has an upwardly projecting finger 84 which moves between two stops 85 on the upper part. This device limits the gripping force of the extra-tension gripper.

The wire is taken from a reel and is engaged between the reel and the reversible feed by a slack take-up device 18. The slack take-up device comprises a lever 87 which is pivoted to a fixed block 88 at its lower end and carries wire guiding rollers at its upper end. A spring 90 acts between the lever and a valve plate 91 also pivoted to the block. The spring is supported by a curved rod 89 which is attached to the valve plate and slides through a hole in the lever. The valve plate controls a bleed port 108 in the block 88. During the first part of forward feed, the feed rollers remove the slack from the wire and the lever 87 is raised towards the block. The spring is thus caused to drive the valve plate against the bleed port to stop the flow of air which at this time is being discharged from it.

The pressure signal thus developed in the air duct leading to the bleed port 108 is utilised to operate doubleacting air cylinder K, which is adapted to rotate the reel.

The reel is mounted on a sleeve which is rotatably mounted on a fixed shaft 92. The sleeve carries a disc 93 to which the reel is drivably connected by an axially extending pin (not shown) which fits into a socket in the disc. The cylinder K is pivoted to a brake lever 94 carrying a brake pad 95 and the piston rod is pivoted to a driving lever carrying a driving pawl 96. The driving lever is pivoted to the reel shaft and the brake lever is pivoted to a fixed pin which is eccentric of the shaft. When the.

reel cylinder extends its rod, the pawl kicks the disc and thus rotates the reel, which pays off wire. When the reel cylinder retracts its rod the brake pad re-engages the disc and thus stops the reel.

The various operations of the machine are carried out in an automatic sequence. FIGURE 4 shows the air circuit and the positions of the components at the beginning of a cycle. The ring is closed and loaded with wire, the free end limb of the loop being anchored by the holding gripper. The pseudo-gripper is up, the piston of the overtwist return cylinder B is up and the piston of the twist cylinder D is down. The reversible feed is in neutral, the extra-tension piston is retracted and the reel brake is on. There is a clamping cylinder J for clamping packages during the binding operation. This cylinder is idle at the beginning of the cycle.

The machine is controlled by three mechanically-operated valves, which have already been described, and a number of air-operated valves which are enclosed in a box 99. A compressed air line conducts compressed air from a source through a filter 101 a pressure regulator 102 and a lubricator 103 to an emergency stop valve 104 which, in the position illustrated, allows this air to pass toall the valve air inlets, each of which is denoted by a circle. The valve air outlets are denoted by arrows.

The sequence is started by depressing the push button of manual start valve 105 or the trip lever of auto-trip valve 106. The latter is actuated by placing a package within the loop. On actuation of either of these valves air passes from the inlet of ring cylinder valve A through pressure drop valve Z and the starting valve to the right hand side of pilot valve L. Pilot valve L reverses and sends its own air through pilot valve M to cylinder valve J,

ring cylinder valve A and overtwist return cylinder valve D all of which are reversed. Consequently the ring opens, the package clamp 115 (see FIGURE 4) comes down and the striker pin is retracted from one of the recesses in the far side ratchet disc. The reversal of the cylinder valve A cuts the air supply to the starting valves, which are now inoperative.

The reversal of cylinder valve A also exhausts the front ends of the ring cylinders and the resulting pressure drop enables pressure drop valve 2.; to reverse and send its own air through pilot valve P to reverse-feed cylinder valve G G reverses against its spring and sends its own air to the reverse-feed cylinder G. Reverse-feed thereupon begins and continues until the loop has contracted so tightly onto the package that the tension in the wire equals the pull of the reverse feed rollers, whereupon the rollers climb the wire and effect operation of the trip valve V.

Trip valves V ends its own air to pilot valve P. Valve P reverses and first diverts the signal from pressure drop valve Z, to extra-tension cylinder valve C subsequently exhausting reverse-feed cylinder valve C which is reset by its own spring to stop the reverse feed. Cylinder valve C now reversed, sends regulated pressure to the extratension cylinder C which applies extra tension to the wire round the pack. The regulated pressure is also applied through an adjustable orifice to the twist cylinder valve D The orifice can be adjusted to vary the extra-tension/ twist sequence. The cylinder valve D reverses and the twist cylinder D commences its upstroke. Twist and overtwist are thereby applied to the overlapping ends of the loop. At the top of the upstroke the trip valve Tis actuated in the manner already described. Trip valve T sends a signal to pilot valve M. Pilot valve M reverses and diverts the signal from valve L to pilot valve N, package clamp cylinder valve 1,, and twist cylinder valve D It is also exhausts cylinder valve B which is reset by its spring. Thus, the overtwist return cylinder B returns the twister pinion through the angle of overtwist, the package clamp is released and the stroke of twist cylinder D is reversed. It would appear impossible for the signal from valve L to reset cylinder D since the reversing signal from valve C, has not yet been removed from that valve. However valve D is controlled by two pistons working in separate chambers and air can be admitted to these chambers on both sides of each piston. The resetting signal from valve L not only applies a resetting pressure to one of these pistons but also cancels the reversing signal on the other. The air diverted to pilot valve N is applied to cylinder valves B and F These valves reverse and the pseudogripper and the holding gripper go down to permit ejection of the tie. The loop, it will be remembered, was severed from the supply of wire during the overtwist.

Near the bottom of its downstroke, after ejection of the tie, the twist cylinder D actuates trip valve U which thereupon sends a signal to pilot valve N. Pilot valve N reverses and diverts air to cylinder valve A at the same time as it exhausts cylinder valves B,, and F.,. F is reset by its spring and the pseudo-gripper goes up in readiness for the forward feed. A is reset and the ring is thereby closed. Resetting of A leads to resetting of 2.; to remove the signal from extra-tension cylinder v-alve C This valve is reset by its spring and the extra-tension cylinder retracts the extra-tension lever.

As well as applying air to cylinder valve A pilot, valve N also applies air to pressure drop valve Z which cannot pass through until the twist cylinder has completed its down-stroke. When this is so pressure drop valve Z is reset and the signal passes through to pressure drop valve Z This valve is not reset until the pseudo-gripper is fully up. When this is so the signal passes through to reverse the forward-feed cylinder valve H H sends air to the forward-feed cylinder H and forward feed commences.

At this moment air is bleeding through the bleed port 63a in the nose plate and also through the bleed port 108 controlled by the valve plate 91 which is associated with the slack take-up device. When the Wire is fed forward, the slack is removed and thus, as already explained, leads to closure of port 108 in the block 88. Pressure builds up in the air duct leading to port 108 and reverses relay valve R, which sends its own air to reverse the cylinder valve K. Consequently, reel cylinder K kicks the reel and wire is paid off to prevent the feed rollers pulling- W-ire off the reel. When the wire is fed fully round the ring it blocks the wire bleed port 63a. Pressure builds up in the air duct '63 and this operates relay valve S, which sends a signal to reset pilot valve L. Pilot valve L sends air to reset cylinder valves E and H thus stopping the forward feed and closing the holding gripper. It also resets pilot valves- M, N and P for the next cycle of operations. The air that drives up the holding gripper also resets the cylinder valve K to prevent more Wire being fed off the reel. This ends the cycle.

When the ring is closed, air is sent to pressure drop valve Z which cannot pass until the holding gripper is fully up. When this is so Z is reset and the signal passes through to the starting valves in readiness for the next cycle.

The circuit also includes an emergency stop button 109, depression of which reverses the emergency stop valve 104. Reversal of the emergency stop valve exhausts the air from the control system and also supplies air to the appropriate places to reset all valves to the starting position. Depression of the reset button 110 now resets the emergency stop valve, thus re-applying air to the control system, now in the starting position.

When it is desired to load thernachine with wire the emergency stop button must first be depressed. Air is then fed to the wire load push button 111, which when depressed applies air at a limited rate to keep the ring closed, the holding gripper down, the pseudo-gripper up, the piston rod of the overtwist return cylinder extended and the forward feed pressure roller down. It also operates cylinder K which takes off the brake and kicks the reel. When wire has been fed round the ring, the wire load push button can be released and the system reset. The machine is then ready for operations.

I claim:

1. A feed drive mechanism for controlling'the feeding and retraction of binding material in a package binding machine, comprising a forward driving roller and a reverse driving roller rotatably mounted in a support, common driving means coupled to said forward and reverse driving rollers and operative to drive said rollers continuously in opposite directions of rotation, a forward drive pressure idler rotatably carried adjacent said forward driving roller, a reverse drive pressure idler rotatably carried adjacent said reverse driving roller, said pressure idlers being rotatably mounted in a tilting holder pivoted on said support, fluid pressure motor means being provided mounted between said tilting holder and said a support and selectively operable to pivot said tilting holder in one direction to move one pressure idler into running engagement with its corresponding driving roller and in the opposite direction to move the other pressure idler into running engagement with its corresponding driving roller, the tilting holder having an intermediate in-v operative position in which neither pressure idler is in running engagement with its corresponding driving roller.

2. A feed drive mechanism according to claim 1 wherein said support is pivotally mounted on a package binding machine and is biassed into a normal operative position, and further comprising an extra-tension device carried on said machine and operable on retraction of said binding material onto a package to be bound to engage said 'binding material and apply an additional tension thereto, actuating means for said extra-tension device mounted on said machine adjacent said support, said actuating means being operable by said support, on pivotal movement thereof on completion of retraction of said binding material by said feed drive mechanism, to actuate said extra-tension device.

3. A feed drive mechanism according to claim 2 Wherein said extra-tension device comprises, a pivot on said machine, a lever mounted on said pivot, 21 gripper on said lever for engaging said binding material, fluid pressure motor means connected between said lever and a fixed part of said machine, said actuator means comprising a valve mounted on said machine and operable on pivotal movement of said carrier to actuate said fluid pressure motor means to pivot said lever thereby causing said grip. per to engage and apply a tension to said binding material.

4. A feed drive mechanism for controlling the feeding and retraction of binding material in a package binding machine, comprising a forward driving roller and a reverse driving roller rotatably mounted in a support, common driving means coupled to said forward and reverse driving rollers and operative to drive said rollers continuously in opposite directions of rotation, a forward drive pressure idler rotatably carried adjacent said forward driving roller, a reverse drive pressure idler rotatably carried adjacent said reverse driving roller, actuating means alternatively operable to move each pressure idler into running engagement with its corresponding driving roller to efiect movement of said binding material, said support being pivotally mounted on said machine and biassed into a normal operative position, in combination with an extratension device mounted on said machine and operative in response to pivotal movement of said support on attainment of a predetermined tension in said binding material during retraction thereof, to engage said binding material and apply an additional tension thereto.

r BILLY J. WILHITE,

5. The combination according to claim 4 wherein said extra-tension device comprises a pivot on said machine, a lever mounted on said pivot, a gripper carried on said lever and operative to engage said binding material, fluid pressure motor motor means connected between said lever, and a fixed part of said machine and operative to pivot said lever, actuator means comprising a valve mounted on said machine adjacent said suport and operative in response to pivotal movement of said support on attainment of said predetermined tension to actuate said fluid pressure motor means to pivot said lever, engage said gripper and apply said additional tension to said binding material.

References Cited UNITED STATES PATENTS 2,136,225 11/ 1938 Williams 26 2,195,043 3/1940 Wright 100-26 2,215,121 9/1940 Harvey et a1 IOU-26 X 2,707,430 5/1955 Leslie et a1. 100-26 X 2,812,707 11/1957 Cheesman IOU-31 2,880,666 4/1959 Rogers 100-31 X 3,012,497 12/1961 Fryer 10026 3,046,871 7/1962 Cheesman et al 100-26 3,057,289 10/1962 Luthi 100-26 3,086,451 4/1963 Van Der Wal 10026 3,116,681 1/1964 Van De Bilt 100'26 3,146,695 9/1964 Van De Bilt 1004 3,179,037 4/ 1965 Cranston et a1. 100-4 3,196,779 7/1965 Embree 100-4 Primary Examiner.

Claims

1. A FEED DRIVE MECHANISM FOR CONTROLLING THE FEEDING AND RETRACTION OF BINDING MATERIAL IN A PACKAGE BINDING MACHINE, COMPRISING A FORWARD DRIVING ROLLER AND A REVERSE DRIVING ROLLER ROTATABLY MOUNTED IN A SUPPORT, COMMON DRIVING MEANS COUPLED TO SAID FORWARD AND REVERSE DRIVING ROLLERS AND OPERATIVE TO DRIVE SAID ROLLERS CONTINUOUSLY IN OPPOSITE DIRECTIONS OF ROTATION, A FORWARD DRIVE PRESSURE IDLER ROTATABLY CARRIED ADJACENT SAID FORWARD DRIVING ROLLER, A REVERSE DRIVE PRESSURE IDLER ROTATABLY CARRIED ADJACENT SAID REVERSE DRIVING ROLLER, SAID PRESSURE IDLERS BEING ROTATABLY MOUNTED IN A TILTING HOLDER PIVOTED ON SAID SUPPORT, FLUID PRESSURE MOTOR MEANS BEING PROVIDED MOUNTED BETWEEN SAID TILTING HOLDER AND SAID SUPPORT AND SELECTIVELY OPERABLE TO PIVOT SAID TILTING HOLDER IN ONE DIRECTION TO MOVE ONE PRESSURE IDLER INTO RUNNING ENGAGEMENT WITH ITS CORRESPONDING DRIVING ROLLER AND IN THE OPPOSITE DIRECTION TO MOVE THE OTHER PRESSURE IDLER INTO RUNNING ENGAGEMENT WITH ITS CORRESPONDING DRIVING ROLLER, THE TILTING HOLDER HAVING AN INTERMEDIATE INOPERATIVE POSITION IN WHICH NEITHER PRESSURE IDLER IS IN RUNNING ENGAGEMENT WITH ITS CORRESPONDING DRIVING ROLELR.