GB2184392A - Apparatus for binding bales - Google Patents

Abstract

An apparatus for binding bales 4, which are produced in a baling press 1, with an upper wire 10 and a lower wire 6, which are twisted together, has a binding needle 12 for forming a wire loop or band 18 around the bale, a binding head 30 which is movable in a frame 26 into and out of an operative position and which has a twisting wheel 33 having a slit for producing two twists situated one behind the other between the two wires and a cutting device 39 for cutting through the wires between the twists. The apparatus can be operated with reduced mechanical complication and expense without the risk of wire breakage and is suitable for the binding of bales 4 of short residual lengths, owing to the provision of a head pulley 14, which is mounted on the binding needle 12 and has a single common groove 25 for receiving both the wires 6, 10. The deflected upper wire 10 is supplied to the groove 25 as viewed in the direction of pressing, from the same side of the needle 12 as the lower wire and a knife beam 16, which is mounted fixed in the frame 26 above the binding head 30, has an opening for the binding needle which is movable up and down in the direction of its longitudinal axis. The knife beam 16 cooperates with the binding head 30, when the head is withdrawn from its operative twisting position to cut the wire. <IMAGE>

Description

SPECIFICATION Apparatus for binding bales This invention relates to an apparatus for binding bales produced in a baling press by means of an upper wire and a lower wire, which are twisted together to form a band around the bale, the apparatus comprising a binding needle for forming a loop in the wires, a binding head, which is movable into and out of an operative position and has a twisting wheel for forming two twists spaced apart from each other and connecting the wires to each other in spaced apart positions, and a cutting device for cutting through the wires between the two twists.

An example of such an apparatus is disclosed in German Patent Specification No. 2 419 151. This apparatus avoids overstressing of the binding wire and consequent frequent breakages by swinging the twisting and cutting device into the vicinity of the wire during the twisting operation. Nevertheless, occasional wire breakages still cannot be avoided.

During the twisting together of the two wires, two twists, one extending above and one extending below the twisting wheel for a certain length are formed. A twisting wheel which comprises a slit which receives the two wires but has a narrower width than the thickness of the twists is used. Above the twisting wheel both a bending die and a feed fork for the wires are disposed. The bending die bends the twist, which extends above the twisting wheel after cutting, over and around.

This prevents opening of the twisted wire.

The feed fork, which lies in a common vertical plane with the twisting wheel, is necessary firstly to ensure a defined length of the twist and secondly, when the binding needle is in a lowered position at the bottom of the bale, to move the wire loop raised by a capture hook of the binding needle by a pivotal movement about a pivot pin out of the region of the binding needle. This enables the needle to travel back into its raised, waiting position.

The fork nevertheless, sometimes causes wire breakages because the upper twist which connects together the upper and lower wires into an endless wire after the wires have been cut between the twists is pulled into the slit of the fork when a bale to be bound is fed forwards and jams there, which leads to wire breakage. As soon as one binding loop or band, of which there are several around each bale, fails, the resultant inadequately bound bale must be removed from continuous production. This leads to loss of production and time-consuming operating faults in the operation of the baling press.

The components in the existing baling presses, which are necessary for maintaining production and are situated above the binding head, such as the bending die, cutting devices and especially the feed forks, which are each disposed at a distance above the binding head, therefore necessitate a relatively large constructional expense. This must however be accepted in order to make possible at all the automatic binding of bales, because this comprises at least both the aforementioned, defined twisting together of the wires and also the cutting through of the wires between the twists and the release of the capture hook of the binding needle from the wire loop by means of the feed fork and by inwardly pivotal movement of the cutting device.

Furthermore, because these components are situated one above another, it is also necessary to raise the binding needles during twisting of the wires to a position situated well above the forks, in order reliably to prevent the upper twist above the cut failing to enter the region of the binding device when the connected wires are pulled forward by the feed movement of the bale. This large distance of movement of the needle has the result that minimum lengths of the bales to be bound of approximately 1000 mm must be present and shorter bales cannot be bound.

This is a disadvantage especially where materials of high value are being pressed.

The object of the present invention is so to improve a binding apparatus as initially described that the aforementioned disadvantages no longer arise and, in particular, automatic operation with reduced constructional expense is possible without, or with reduced, risk of wire breakages occurring. Furthermore, the apparatus preferably also makes it possible to bind even short residual bale lengths of less than 1000 mm.

To this end, according to this invention, in apparatus for binding bales as initially described, a head pulley is mounted on the binding needle and has a single peripheral groove for receiving both the wires, means is provided for supplying the upper wire to the pulley from the same side of the needle as the lower wire, considered in the direction in which the bales are pressed from the press, and a knife beam is mounted in a fixed position in a frame, in which the binding head is movably mounted, above the binding head, the knife beam having an opening for the binding needle which moves up and down in the direction of its longitudinal axis, and the binding head cooperating with the knife beam when the head is in its operative, twisting position.

It has surprisingly been found that with the arrangement in accordance with the invention the feed fork in particular which requires considerable space above the binding head in existing bale binding apparatus, is no longer necessary when the groove of the head pulley is sufficiently deep and has space for receiving both the wires.

After the cutting through of the wires be tween the twists, the upper twist which connects together the wires fed from the same side can run over the head pulley, so that no additional disengagement movement of the wires from the needle is any longer required.

This means that the pulley releases the wire without its being caught and thereby leading to breakage. By the omission of the feed fork, the distance of the binding needles, when fully raised, above the binding head can be greatly reduced, so that even short residual bale lengths of, for example, approximately 500 mm can be bound. The upper twist, which is limited by the head pulley of the binding needle immediately above the binding head, immediately moves out of the region of the binding device when the wire is pulled through by the bale because the twist is only a short distance from the binding head.

The considerable space saving which is also achieved, enables the stationary knife beam in the frame to cooperate with the adjustable binding head when this is in its operating position, i.e. the twisting position. Therefore, an actuating cylinder for traversing a cutting beam equipped with knives, which has been necessary in the existing apparatus in addition to a cylinder for moving the binding head into and out of its operative position, can be dispensed with. So also can slide guides and lever linkages for the cutting beam which were also previously necessary. This is because the return stroke of the binding head, which has been moved into its operative position for the twisting operation, can be utilised without an additional operation for cutting through the wires between the twists by means of the stationary cutting beam.For this purpose the wires enclosed by the slit of the twisting wheel are cut through between the twists at the instant at which the binding head arrives in the region of the knives of the stationary knife beam. The opening in the stationary knife beam ieaves sufficient room for the passage of the binding needle for seizing and threading the lower wire which is supplied beneath a pressing duct of the baling press in which the bales are formed.

The deep groove of the head pulley of the binding needle which receives both the wires thus not only permits independent running through of the upper twist which connects the wires together without requiring auxiliary equipment, which would if present increase the risk of wire breakage, but also equally makes possible the combination of the operation of cutting through the wires with the twisting or with the return movement of the binding head. It also makes possible the binding of short residual bale lengths.

The slit in the twisting wheel advantageously has sharp cutting edges, these being in the region of the radially innermost edges of the slit. The twisting wheel may then fulfil a twofold function, namely in addition to the twisting it also acts as a counterknife for cutting the wires in cooperation with the fixed cutting beam. The twisting wheel is, for this purpose, rotated through 1800 from its threading-through position in which the slit is open towards the wires.

Preferably, the twisting wheel has, on its upper side facing towards the knife beam, a rotary knife which is disposed coaxially with the twisting wheel and extends over it. In this case the rotary knife, which like the twisting wheel is slit and, in the threading position, forms with the slit of the twisting wheel a common slit seating for the wires, performs the function together with the counter-knives of the knife beam of cutting through the wires between the twists. The twisting wheel may advantageously be releasably connected to the rotary knife.

The advantage of this two-piece construction lies especially in the fact that, not only can the rotary knife having cutting edges be simply replaced by a new knife, for example when worn, but also that by pulling out the twisting wheel upwards, the engagement position of the wire twist can be made accessible.

The twisting wheel may be driven by a rotary or reciprocating hydraulic motor, preferably via a transmission composed of gear wheels. The hydraulically driven motor, which may be mounted centrally on the binding head, can be continuously rotated so that the number of turns in the twists can be made as large as desired and is no longer limited, as in the existing apparatus, by the stroke of a hydraulic cylinder which rotates the twisting wheel by means of a rack. This means that the number of turns can be increased, for example by means of a selector switch in a central control console of the binding apparatus, for instance to 8 or 10 turns. This is sufficiently high to prevent slipping of the twisted connections after the cutting through of the wires between the twists. An additional bending device for bending over the twists to lock them is then no longer necessary.

The hydraulic motor may be connected with a gear wheel of a trip cam which controls the starting and stopping positions of the twisting wheel by means of initiators, for example proximity switches. Preferably, in this connection a gear wheel of the trip cam has the same pitch circle diameter as a gear ring of the twisting wheel, and the initiators are displaced by 1800 from one another. The first initiator then determines the threading-in position of the twisting wheel and the second initiator determines the cutting position of the twisting wheel with the rotary knife. In this manner, both the slit of the twisting wheel and that of the rotary knife can be exactly aligned for threading in the wires and also accurately stop in the cutting position, rotated from the threading position by 1800. This is achieved by the gear rings having the same pitch circle diameters as each other and both being driven by the same output gear wheel of the hydraulic motor so that the twisting wheel rotates with the rotary knife through the same angle as the trip cam. As soon as the trip cam and either the one or the other initiator lie centrally adjacent each other, the location of the twisting wheel and the cutting wheel in either the threading-in or the cutting position is ensured.The exact positioning can be effected by an inching movement, brought about for example by a sensitively adjustable throttle disposed in a hydraulic supply line to the hydraulic motor.

An example of an apparatus in accordance with the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a side view of a baling press incorporating the example of the apparatus in accordance with the invention; Figure 2 is a view to a much larger scale of the lower part of a binding needle, including a head pulley, which forms a part of the apparatus; Figure 3 is a section on the line Ill-Ill in Figure 2; Figure 4 is a diagrammatic representation of a phase of the operation of the apparatus after completion of twisting of the binding wire; Figure 5 is a plan view partly in section of a binding head which forms part of the apparatus and is moved in a slide frame of the apparatus into a twisting position; Figure 6 is a section on the line VI-VI in Figure 5;; Figure 7 is a detail of the apparatus showing a twisting wheel with a rotary knife, as seen in section on the line VII-VII of Figure 5, but with a knife beam, which is disposed above the twisting wheel, omitted; Figure 8 is a plan view of a rotary knife forming a part of the apparatus; and, Figure 9 is a section on the line IX-IX of Figure 8.

The baling press has a pressing duct 1 of rectangular section in which a pressing ram 2 is slidably mounted and is moved by a drive, which is not illustrated. When the pressing ram 2 is retracted, material to be pressed into bales is introduced by a filling shaft leading from above into the pressing duct 1. To produce each bale, several workjng strokes of the pressing ram are necessary. In the pressing duct 1, as shown in Figure 1, three pressed bales of waste paper 4 are already situated, of which the central and righthand bales have already been bound with wire, while the lefthand bale is just about to be bound. A lower binding wire 6 runs from a lower storage reel 5 beneath the pressing duct 1, around a deflecting roller 7 and up the front end face 8 of the bale just about to be bound.It is connected with an upper wire 10, which is drawn from an upper storage reel 11, at the upper side of this bale at a twist position 9. The production of the twist connection is described later.

A binding needle 12 moves up and down in the direction of its longitudinal axis with a head pulley 14 journalled in a captive hook 13. The needle 12 is able to pass through an opening 15 of a stationary knife beam 16, which is disposed above the pressing duct 1, and through the pressing duct 1 via a groove 17 which is formed in the head of the pressing ram 2. The needle 12 pulls up a loop 18 from the lower wire 6 as far as the upper side of the pressing duct.

The lower and upper wires 6, 10 are fed to the binding needle 12 from the same side, namely from the front side of the binding needle as viewed in the pressing direction of an arrow 19, the upper wire 10 being guided in an S-shape between two guide sheaves 20, 21 and then being fed to the head pulley 14.

The head pulley 14, which is enclosed within the capture hook 13 itself secured by a bolt 22 to the binding needle 12 and is rotatably journalled between these components on a pin 23 and bush 24, has a circumferential groove 25 of such a depth that the wires 6, 10, lying one above another, can be received in it (see Figures 2 and 3).

Guide rails or bars of a slide frame 26 are mounted on the pressing duct 1 behind the plane of action of the binding needle 12 considered in relation to the pressing direction 19. A binding head 30, which is assembled from an upper plate 28 and a lower plate 29 (Figure 7) and is illustrated in Figure 5, can be moved in the frame 26 from a retracted, inoperative position into the twisting position shown by means of a hydraulic adjustment ram 27. The limiting positions of the inding head 30 are monitored by an initiator 3 1 for the noperative position and an initiator 32 for the twisting osition. The binding head 30 has a number of cylindrical twisting wheels 33, equal to the number of loops or bands of binding wire applied to the bale by the apparatus, the loops or bands being disposed parallel to each other and spaced apart.In this example, five twisting wheels are present, and it should be mentioned that for each bale a plurality of loops, disposed parallel to one another, are usually provided, the number depending upon the dimensions of the bale. For simplicity, however, in Figure 1 only one binding needle for one wire loop is illustrated, although in practice several will be disposed in alignment perpendicular to the plane of the drawing.

Each twisting wheel 33, which has a gear ring 34, is provided with a radial slit 35 for receiving the wires 6, 10. The twisting wheels 33 are driven by gear wheels, which are themselves driven by a reciprocating hydraulic motor 36 to twist the upper and lower wires 10, 6 together. As shown in Figure 4, starting from the two flat faces of the twisting wheels 33, a lower twist 9 and an upper twist 38 are produced. These are separated from one another by cutting the wires between them in a manner, which will be described, by means of the stationary knife beam 16. After cutting, the upper twist 38 runs through the groove 25 of the head pulley 14 and releases the binding needle 12, so that the latter can be moved to a raised, waiting position until the renewed threading in of the lower wire 6 has taken place.

For cutting through the twisted wire midway between the upper twist 38 and the lower twist 9, the twisting wheels 33 are releasably connected, at their upper sides towards the knife beam 16, with pot-shaped, rotary knives 39 which fit over them, i.e.

which are concentrically inverted on the twisting wheels 33. The rotary knives 39 have, like the twisting wheels 33, a slit 40, which is Vshaped at its entrance to assist in threading in of the wires. The slit 40 has, at least at its radially innermost region, sharp cutting edges 41 (Figures 8 and 9). The installed position of the twisting wheel 33 with the rotary knife 39 in the plates 28, 29 or hollow profile of the banding head 30 is shown in Figure 7. A lower rotary disc 42 as well as the twisting wheel 33 and the rotary knife 39 are here held together with a connecting bolt 43 which passes centrally through these components.

The rotary knife 39 and the rotary disc 42 are also secured by pins 44 against rotation. The twisting and cutting unit is supported by bearing bushes 45, 46, of which the upper bearing bush 45 is connected only by a pin 47 with the upper plate 28 of the binding head 30 for ease of removal. The lower bearing bush 46 is secured by bolts 48 to the lower plate 29.

To drive the twisting wheels 33, the motor 36 has an output gear wheel 49, illustrated in Figure 5, meshing both with the gear ring 34 of the central twisting wheel and also with two intermediate wheels 50, 51, which have the same pitch circle diameter as the gear wheel 49 of the motor 36 and each of which meshes with gear rings 34 of the two outer most twisting wheels. In order that the exact threading-in positions of the slits 35 and 40 of the twisting wheels 33 and the rotary knives 39 respectively, which open towards the wires, can be monitored, the intermediate wheel 51 meshes also with a pinion 52 of a trip cam 53. The pinion 52 has the same pitch circle diameter as the gear rings 34 of the twisting wheels 33, so that the trip cam is turned exactly by the same angular distance as the twisting wheels 33.Two initiators 54, 55 are associated with the trip cam 53 and lie in alignment opposite each other, i.e. they are displaced by 1800 from each other, with the trip cam 53 between them. The initiator 54 monitors the threading-in position, shown in Figure 5, the trip cam 53 being exactly adjacent the initiator 54 when this position is reached.

After rotation through 1800, the trip cam 53 is adjacent the initiator 55 and the twisting wheels 33 with the rotary knives 39 then adopt their cutting positions for cutting through the wires 6, 10. This situation is illustrated in Figure 5 for the twisting wheel and rotary knife in the encircled region marked "X". Here, the slits 35, 40 are oriented inwards, i.e. the wires are enclosed and lie against the sharp cutting edges 41 of the rotary knife 39. If the adjustment cylinder 27 is reversed, causing the binding head 30 to be moved in the slide frame 26 in the pressing direction 19 backwards into its inoperative position, the wires 6, 10 meet cutting knives 56, which are mounted by screws 57 in the stationary knife beam 16.The stationary knife beam 16 is secured by fixing bolts 58 to the front end of the slide frame 26 above the plane of the binding head 30, so that the binding head, when in its advanced operative or twisting position, is situated underneath the cutting beam 16. The retraction of the binding head 30, into its inoperative position, which is in any case necessary, is thus simultaneously utilised for cutting through the wire between the twists, so that a further cutting device, which would need to be operated by a separate drive, becomes unnecessary.

During twisting, a shortening of the wires takes place at the twist positions. This can be compensated in the case of the upper twist 38 quite simply by pulling further lengths of wire from the feed reels 5, 11. In contrast, pulling through of wire for the lower twist 9 is not possible, because the slit 35 in the twist wheel 33 has only the width of one wire thickness, so that the upper twist 38, which accordingly is at least twice as thick as the width of the slit, cannot be pulled downwards through the slit 35. Pulling of wire through the slit 35 would, moreover, also be undesirable because in such a case reliable twisting would no longer be ensured. To compensate for this difference in length, the slide frame 26 is therefore made of resilient construction. For this purpose, it rests in rear guides 59 and also bears by forwardly situated bolts 60 and compression springs 61 situated therebetween resiliently upon the pressing duct 1. The force of the springs 61 can be so designed that a movement of the binding head 30 and thus of the slide frame 26 does not occur until a specific tensile force in the binding wire portions has been exceeded, so that the necessary wire tension is always present for binding.

Claims (10)

1. Apparatus for binding bales produced in a baling press by means of an upper wire and a lower wire which are twisted together to form a band round the bale, the apparatus comprising a binding needle for forming a wire loop in the wires, a binding head which is movable into and out of an operative position and has a twisting wheel with a slit for -forming two twists spaced apart from each other and connecting the wires to each other in spaced apart positions, and a cutting device for cutting through the wires between the two twists, wherein a head pulley is mounted on the binding needle and has a single peripheral groove for receiving both the wires, means is provided for supplying the upper wire to the pulley from the same side of the needle as the lower wire, considered in the direction in which the bales are pressed from the press, and wherein a knife beam is mounted in a fixed position in a frame in which the binding head is movably mounted, above the binding head, the knife beam having an opening for the binding needle which moves up and down in the direction of its longitudinal axis and the binding head cooperating with the knife beam when the head is in its operative, twisting position.

2. Apparatus according to Claim 1, in which the wire-receiving slit of the twisting wheel has a sharp cutting edge.

3. Apparatus according to Claim 1 or Claim 2, in which the binding head includes a rotary knife, extending over the twisting wheel on its upper sides facing towards the knife beam, the rotary knife being concentric with the twisting wheel.

4. Apparatus according to Claim 3, in which the twisting wheel is releasably connected to the rotary knife.

5. Apparatus according to any one of Claims 1 to 4, further comprising a reciprocating hydraulic motor for driving the twisting wheel.

6. Apparatus according to Claim 5, in which the motor drives the twisting wheel through gear wheels.

7. Apparatus according to Claim 5 or Claim 6, in which the motor also drives a pinion of a trip cam which controls the starting and stopping position of the twisting wheel by means of initiators.

8. Apparatus according to Claim 7 in which the pinion of the trip cam has the same pitch circle diameter as a gear ring which is fixed to the twisting wheel, and the initiators are displaced by 180O one from the other around the centre of rotation of the trip cam.

9. Apparatus according to Claim 7 or Claim 8, in which a first initiator determines a threading-in position of the twisting wheel in which the wires are fed into the slit of the twisting wheel, and a second initiator determines a cutting position of the twisting wheel with the rotary knife.

10. Apparatus according to Claim 1, substantially as described with reference to the accompanying drawings.