GB2038706A

GB2038706A - Mechanical system for distributing thread in the tying of bales in rotary baling machines

Info

Publication number: GB2038706A
Application number: GB8001014A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-01-11
Filing date: 1980-01-11
Publication date: 1980-07-30
Also published as: FR2446065A1; DE3000908A1; ES476762A1

Abstract

A mechanical system for the distribution of thread (18) used for tying bales in rotary baling machines includes a pulley (1) driven through a clutch (9) from the motive system of the machine. The pulley has an eccentric pivot (12) on which is articulated a tube (13) which guides the tying thread (18) and is automatically reciprocated to feed the tying thread during rotation of the bale so that a greater density of turns are obtained at the ends of the bale than at the centre of the bale. A thread cutting mechanism (16), (17) is actuated by a lever (14) and cable (15). <IMAGE>

Description

SPECIFICATION Mechanical system of distributing thread in the tying of bales in rotary baling machines This invention relates to a mechanical system forthe distribution of th read in the tying of bales in rotary baling machines.

As is already known, conventional rotary baling machines make up the bale without contact with the soil, so that the hook pick-up device continuously deposits the fodder or straw in a container and the belts or rolling drums build up the cylindrical bale until it reaches a predetermined size which may be governed by the actual size of the container, causing the bale to rotate in order that upon completion the bale can be tied.

The process of tying the bale in such machines is carried out in the following manner. As soon as the bale has reached the desired size, the bale is encircled by a series of passes using sisal or similar thread. The reel or thread located in its housing supplies thread via a reciprocating guide tube situated in the front portion of the machine and controlled by the driver from the tractor seat. During baling, the said tube is displaced to one side and in order to tie up the bale, it is essential to pull a cable which causes reciprocation of the guide tube so that the latter turns towards the centre, the thread being retained by the rotating bale around which it becomes wound in a spiral. A thread brake ensures that there is sufficient drag and two lateral limiters prevent the thread escaping at the sides.

Once the thread has been wound around the bale a sufficient number of times, the thread guide tube is again turned to the starting position, by further operation of the pulling cable, at which time the thread is cut, so that the bale is finished and can be ejected from the machine and left on the field.

There are also electrical systems which are based on the use of an electric motor which gives a cyclic reciprocating movement to the guide tube which, in spite of everything, has the disadvantage that it does notsynchronise revolutions of the machine with those of the electric motor so that tying is irregular and it is not possible accurately to assess the number of turns of string applied to each tying operation.

The object of the present invention is to resolve the problems which are currently experienced in the tying of cylindrical bales, using a mechanical system forthe distribution of the thread during the tying of bales in rotary baling machines and is based on the idea of distributing the thread automatically over the bale so that the distance between the turns of string increases progressively towards the centre of the bale and is a decreasing progression towards its two ends.

On the other hand, as has been previously stated, the tractor driver has to pull on a cable to operate the guide tube and has no opportunity to establish where the string is located because he cannot see how it is being distributed over the bale since the latter is not accessible to view from the tractor seat.

In addition, he has to pull a second cable to operate a system which cuts the sisal thread which is wound around the bale.

All this means that the tractor driver is under tension during his work which causes him considerable fatigue and has its repercussions on the efficiency and quality of his work.

Four a better understanding of the invention, one embodiment of the invention will be described with reference to the accompanying drawings, in which: Figure 1 shows a diagrammatic side view of a rotary baler fitted with the system according to the invention; Figure 2 is a front view of said baler; Figure 3 is a plan view of said baler; Figure 4 illustrates the movement of the tying system; and Figure 5 shows the disposition of turns around a bale.

As will be evident from the drawings, the system which is the subject of the present invention, includes a pulley 1 mounted on a shaft suitably mounted on a support which is located in the forward part of the rotary baling machine. The pulley 1 is rotated by a belt 2 provided with a tensioning device, which links it to a pulley 3 which enables the position of the belt to be changed in order to vary the number of turns used in tying a bale.

This pulley 3 is driven by a gearbox or reduction system 4 provided with a pinion 5 which transmits movement by means of a chain 6 to a secondary pinion 7 situated on a shaft 8 suitably supported in bearings in the aforesaid support.

This shaft 8 is connected by a clutch 9 to another shaft 10 which is suitably supported and carries a pinion 11 which is driven from the rotary baling machine through a suitable transmission.

The pulley 1 has an eccentric pivot 12 on which is articulated a guide tube 13 through which passes the tying thread 18. This articulated connection between the two elements is what ensures the reciprocating movement of the guide tube 13 illustrated in Figure 4.

Under these conditions, starting from the position A, Figure 4, when the pulley 1 starts to move in a clockwise direction, the guide tube 13 describes a rapid movement until it reaches the point B and since, from this point until it reaches C, the tube 13 virtually does not move, a greater number of turns of thread are made at the end of the bale, Figures. In its movement from the position C to D, the speed of translatory movement of the tube 13 increases progressively towards bottom centre position E producing a progressive increase in distance between turns. Once position E has been passed, the cycle is repeated in the opposite direction so that there is a decreasing progression between the separation of turns in the direction of the opposite end.

The reason why the turns of tying thread are closer to one another at the ends of the bale is due to the fact that there are the weaker zones which have to be protected so that they do not become segregated during handling of the bale, the same amount of protection not being needed in the central zone which is why the turns are farther apart.

By virtue of the construction and method of operation which have just been described, tying takes place by automatic winding of the thread around the bale in the manner and in the circumstances described, with the advantage that the tractor driver is completely releived of stress throughout the tying up process and can devote his attention to other needs of his job, including the cutting of the thread, because this is effected mechanically through the medium of a lever 14 mounted at its centre on said support and operating a cable 15 which moves a lever 16 to introduce the thread between two blades 17 which are moved by the cable 15, the thread being cut at the moment when the guide tube 13 has reached the starting point A, Figure 4.

It should be pointed out that when the thread is cut, all the mechanism is paralysed, the clutch 9 is disengaged and the whole mechanism is ready to commence a fresh cycle.

Claims

1. A mechaical system forthe distribution of thread used for tying up bales in rotary baling machines, characterised in that a support which is mounted in the front part of the baling machine carries a pulley driven thrugh a clutch from the motive system of the machine, said pulley having an eccentric pivot on which is articulated a tube which guides the tying thread, so that said guide tube is automatically reciprocated to feed the tying thread during rotation of the bale, means being provided to vary the speed of reciprocation of the guide tube so that a greater density of turns may be obtained at the ends of the bale and that the turns are farther apart from one another at the centre of the bale.

2. A system according to Claim 1, characterised in that said pulley is connected by a further pulley to reduction gearing which is in turn, operated by a pinion mounted on a shaft which, by means of a clutch, can be coupled to another pinion which is driven through a transmission from the baling machine so that when the reduction gearing is operated, the number of turns of the tying thread can be varied.

3. A system according to Claim 1 or 2, characterised by a control cord which, after production of a bale, causes the system to engage and commence tying, and a rocker lever which, when tying is completed, is operated to transmit a movement via a cable to another lever which introduces the tying thread between two blades operated by said cable, the thread being cut at the moment when the guide tube has completed the tying cycle and disengagement of the transmission which operates the guide tube operating pulley occurring simultaneously.

4. A mechanical system for the distribution of thread for tying bales in rotary baling machines, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.