WO1992003038A1

WO1992003038A1 - A cutter press and a method in the making of bales

Info

Publication number: WO1992003038A1
Application number: PCT/DK1991/000228
Authority: WO
Inventors: Børge LARSEN
Original assignee: Maskinfabriken Taarup A/S
Priority date: 1990-08-14
Filing date: 1991-08-13
Publication date: 1992-03-05
Also published as: DK38390A; AU8339991A; DK38390D0

Abstract

In a cutter press having a frame (10) which carries a pickup (12) and a feed drum (13) cooperating with cutter knives (14) as well as a compressing chamber (17) equipped with a compressing plunger (21) and receiving cut material from the drum, the compressing chamber is pivotably journalled (18) at its rear end on the frame. The drum (13) presses material up into a stationary feed channel (15), and the compressing chamber (17) has an inlet opening (19) at the front end and an inlet channel (20), which is positioned opposite said opening and surrounds the feed channel (15) telescopically. When the chamber (K) in the compressing chamber between the piston and the already pressed material has been filled, the pressure of the material from the drum lifts the front end of the compressing chamber, assisted by a hydraulic cylinder (25), thereby increasing the volume of the prechamber (Q) formed by the feed channel and the inlet channel, so that the feed drum can continue to press material up into said prechamber, while the compressing plunger completes a stroke and closes the inlet opening (19).

Description

A cutter press and a method in the making of bales

The invention concerns a cutter press of the type defined in the introductory portion of claim 1. Such a cutter press can pick up cut crops lying on the ground, cut them and compress them to bales which, either tied with twine by means of a tying mechanism or wrapped in plastics by means of a mechanism adapted for the purpose, are deposited in the field-

Hydraulic presses are known, e.g. from the DE Patent Specifications 3 809 131 and 3 809 132, which are equipped with a very big prechamber for the material picked up and a rather complicated mechanical device moving the material from the prechamber to the compressing chamber when the plunger has been retracted.

The object of the invention is to provide a cutter press of the present type whose compressing section is simpler and more inexpensive to produce than the known ones, while working more efficiently.

This object is achieved in that the cutter press is constructed as stated in the characterizing portion of claim 1, since, in this structure, the feed channel and the inlet channel telescopically connected with the feed channel form a variable prechamber which is much smaller than in the known process, and which makes special transport means completely superfluous.

A particularly simple embodiment wherein the compressing chamber is pivolly journalled at the rear end is stated in claim 2.

Claim 3 defines an embodiment with a hydraulic cylinder assisting the material pressure generated by the feed drum inlifting the compressing chamber. The hydraulic pressure in this cylinder is adjustable and thus adapted that it only takes a moderate pressure in the material in the prechamber and the compressing chamber to lift it slightly, thereby activating the compressing plunger to perform a stroke.

It has been found that in the compression of straw, grass and the like the compressing action can be improved and the entire compressing process be rationalized when the pressure on the plunger is varied. The embodiment of the cutter press defined in claim 4 enables such variation.

Particularly advantageous embodiments are defined in claims 5-8.

The invention also concerns a method in the making of bales with the stated cutter press, and the unique features of the method of the invention are defined in claim 9.

Advantageous embodiments of the method are defined in claims 10-14.

The invention will be explained below with reference to drawing, in which

fig. 1 is a schematic vertical section through an embodiment of the cutter press of the invention, and

fig. 2 is a side view of such a cutter press with mounted wrapping equipment and discharge slot.

In the drawing 10 is a main frame equipped with ground wheels 30 and a drawbar 11 for coupling to a tractor. In generally known manner, the main fram carries an assembly consisting of a pickup 12, which picks up the material from the ground, and a feed drum 13, which receives the material from the pickup and moves it past cutters 14 up into a feed channel 15. This accommodates two augers 16 passing the material lying thinly in the outer edges of the swath inwardly toward the centre. This assembly 12-16 is driven mechanically from the tractor by known means (not shown).

The material is pressed from the feed channel 15 up into compressing chamber 17, which is pivotably journalled at the rear end on the main frame 10 by means of a shaft 18. In the vicinity of the front end the compressing chamber has an inlet opening 19 and an inlet channel 20 which is arranged opposite the inlet opening and whose walls surround and are telescopically movable with respect to the feed channel 15. A compressing plunger 21 is slidably mounted in the front end of the compressing chamber 17, said compressing plunger being connected partly with a hydraulic drive cylinder 22, partly with a closing plate 23 which is slidable along the bottom of the compressing chamber and closes the inlet opening 19 during the greater part of the plunger movement. The underside of the plunger mounts a rearwardly directed knife 24 which cuts free the material pressed up into the compressing chamber during the compressing movement of the plunger. One end of a hydraulic cylinder 25 is rotatably connected with the front end of the compressing chamber 17 at 26, and the plunger rod of the cylinder is rotatably connected with the main frame 10 at 27.

The compressing plunger 21 is shown in its retracted position in the drawing, and a plurality of compressed portions of material 28, produced by preceding plunger strokes, are shown in the compressing chamber 17. In this position, the feed drum 13 presses cut material up into the compressing chamber part K positioned between the plunger and front portion of material. When this chamber K has been filled, the pressure from the drum 13 tries to lift the front end of the compressing chamber 17, i.e. pivot it about the pivot shaft 18. The hydraulic pressure in the cylinder 25 is adjustable and so adapted that it only takes a moderate pressure in the chamber K from the feed drum 13 to lift the compressing chamber slightly. When the compressing chamber is lifted, a switch (not shown) is activated, causing the plunger 21 to perform a stroke, i.e. first a rearward compressing movement during which the knife 24 cuts through the material in the inlet opening 19, and the plate 23 is caused to close this opening, and immediately thereupon a forward return movement. During the movement of the plunger the drum 13 continues to press material up into the feed channel and the prechamber Q formed by said channel and the inlet channel 20. The hydraulic system keeps the adjusted pressure in the lifting cylinder 25 constant, so that the compressing chamber can still be lifted by a moderate^' pressure in the prechamber Q toward the closing plate 23 of the plunger, thereby increasing the volume of the prechamber.

When the compressing plunger 21 has returned to its shown starting position, the material can freely slide from the prechamber Q up into the compressing chamber section K, and the compressing chamber 17 falls back to the shown starting position, and then a new cycle can begin.

Tying of the bales can be performed in a known manner by means of needles arranged on hydraulically activated swing arms 31, and the knotter mechanism 32 when the plunger 21, whose compressing face is formed with grooves (not shown) for the passage of the needles, is in its extreme position.

All the functions of the compressing section are carried out hydraulically with oil from the tractor or from a separate pump on the cutter press via a hydraulic system (not shown), which is capable of controlling the pressure of the material in the compressing chamber in a known manner, as desired. The most compact bales are achieved when the pressure is kept at a maximum value for a certai time of the order of one to a few seconds at the termi¬ nation of each compressing stroke. However, this advantag is obtained at the expense of the time it takes to make a bale. A less time-consuming, but still efficient method consists in maintaining the maximum pressure for a period of time after the termination of each of the compressing strokes completing the compression of a bale.

Also the plunger rate can advantageously be varied, and it will generally be expedient to control the oil pressure such that the plunger initiates both the compressing stroke and the return stroke at a high speed and terminates at a low speed.

The controlling parameter of the hydraulic system may e.g. be the output signal from a bale measuring wheel or from a counter mechanism or the like.

The amount of material left in the prechamber Q at the termination of the operation, is moved up into the compressing chamber by means of a sector 34 fitted on a rotatable shaft 33, said sector consisting of a plurality of parallel plates which, upon rotation of the shaft, protrude into slots in the walls of the feed channel 15 and the inlet channel 20 facing the shaft. This sector 34 is operated by a hydraulic cylinder (not shewn). In fig. 2, a cutter press according to the invention is shown with mounted equipment for automatic wrapping of the bales in plastics bags. The equipment consists of a feed roll 35 mounted above the rear part of the compressing chamber and on which there is wound a carrier band 36 with four-sided openings corresponding to the cross-section of the compressing chamber and with the edges of folded plastics bags 37 attached along the edges of the openings, as well as of a roll 38 arranged below the compressing chamber to receive the carrier band freed of bags. The • rear end of the main frame 10 mounts an inclined rolling chute 39 along which the wrapped bales 40 can slide down on to the ground.

The details of the cutter press shown and described can be modified in many ways within the scope of the invention. For example, the compressing chamber may optionally be parallel-slidable instead of pivσtable.

Claims

P a t e n t C l a i m

1. A cutter press with a frame carrying an assembly consisting of a pickup and a feed drum, which cooperates with cutters and from which cut material can be moved up into a compressing chamber, arranged on the frame, throug a feed channel forming a prechamber, c h a r a c t e r ¬ i z e d in that the compressing chamber is so arranged o the frame that at any rate its front part can move in a direction toward and away from the feed channel and has o this part an inlet channel which is telescopically connected with the feed channel.

2. A cutter press according to claim 1, c h a r a c t e r i z e d in that in the vicinity of its rear end the compressing chamber is pivotally journalled on the frame about a substantially horizontal pivot shaft.

3. A cutter press according to claim 1 or 2, c h a r a c t e r i z e d in that a hydraulic cylinder is placed between the frame and the compressing chamber, preferably at the front end of said chamber.

4. A cutter press according to claim 1, 2 or 3, wherein the compressing chamber contains a hydraulically driven plunger and receives hydraulic oil from a hydraulic system, c h a r a c t e r i z e d in that the hydraulic system is adapted to control the plunger pressure in the compressing chamber in a predetermined manner.

5. A cutter press according to claim 4, c h a r a c t e r i z e d in that the hydraulic system is adapted to control the plunger pressure such as to maintain a maximum pressure for a predetermined period of time at the termination of selected compressing strokes.

6. A cutter press according to claim 4 or 5, having needles for passing tying twine up in front of a com¬ pressed bale to a tying mechanism positioned above the bale, c h a r a c t e r i z e d in that the compressing face of the plunger is formed with channels for the passage of the needles.

7. A cutter press according to claim 5 or 6, c h a r a c t e r i z e d in that the period of time during which the pressure is kept at a maximum value is adjustable.

8. A cutter press according to any of claims 4-7, c h a r a c t e r i z e d in that the hydraulic system is adapted to control the pressure such that the plunger moves at various speeds during the compressing stroke and/or the return stroke.

9. A method in the making of bales with the cutter press according to any of claims 4-8, c h a r a c t e r i z e d by keeping the hydraulic oil at a maximum pressure for a certain time after the termination of each compressing stroke which terminates compression of a bale.

10. A method according to claim 9, c h a r a c t e r ¬ i z e d in that the tying operation is carried out while the maximum pressure is maintained.

11. A method according to claim 8, 9 or 10, c h a r a c t e r i z e d in that the maximum pressure is maintained for a time after the termination of each compressing stroke.

12. A method according to claim 9, 10 or 11, c h a r a c t e r i z e d in that the compressing stroke begins at a high speed and terminates at a lower speed.

13. A method according to claim 12, c h a r a c t e r ¬ i z e d in that the return stroke begins at a high speed which rapidly declines to a lower speed.

14. A method according to claim 13, c h a r a c t e r ¬ i z e in that the lower speed of the return stroke corresponds to the high speed of the compressing stroke.