GB2100766A

GB2100766A - Device for opening thread bales

Info

Publication number: GB2100766A
Application number: GB08215491A
Authority: GB
Inventors: Georg Goldammer
Original assignee: Schubert und Salzer Maschinenfabrik AG
Current assignee: Rieter Ingolstadt GmbH
Priority date: 1981-05-27
Filing date: 1982-05-27
Publication date: 1983-01-06
Also published as: DE3121030A1; FR2506793A1; IT8221320A0; IT1190829B

Abstract

Apparatus for opening fibre bales comprises a plucking roller (2) which acts from above the bales and a restraining device (6) which is pivotally mounted and associated with the plucking roller (2). The restraining device (6) rests on the bales and extends along the whole working width of the bales. The apparatus is improved in that the free end of the restraining device (6) which extends towards the point (A) at which material is removed from the bale, lies outside the impact circle of the plucking roller (2). <IMAGE>

Description

SPECIFICATION Apparatus for opening thread bales The invention relates to apparatus for opening fibre bales, with a plucking roller which acts on the bales from above, and with a restraining device which is associated with the plucking roller and is pivotably mounted, this restraining device resting on the bale and extending along the plucking roller over the whole working width of the latter.

It is known to provide, for co-operation with the plucking roller which removes fibre material from the surface of the bales a restraining device which presses against the upper layer of fibres of the bale so as to hold this upper layer down (US-PS 4297767). In this way it is ensured that the plucking roller will not tear some lumps of fibres out of the bales. In this known apparatus, which constitutes the prior art of the present invention, a pivotably mounted grid or grating is provided as a device for restraining the fibrous material, the pins or teeth of the plucking roller passing through this grating. The bars of the grating are open at their ends lying in the range of engagement of the plucking roller, thereby ensuring that the grating will not prevent the removal of tufts of fibre from the surface of the bale.This entails the drawback, that when the pins or teeth of the plucking roller move along the bale, they leave behind furrow-like grooves on the surface of the bale while, at the points at which bars of the grating lie on the bale, these pins or teeth form raised portions or ridges, which must be subsequently removed by the plucking roller. In the case of the known apparatus, for this purpose, adjacent grating bars are so mounted that they can turn independently of one another, or two opposed gratings are arranged in front of and behind the plucking roller, the bars of these gratings engaging, in offset fashion, into the gaps between the pins of the plucking roller; on the occasion of each forward or reverse stroke of the apparatus for the removal of material from the bale a set of grating bars, or one of the two gratings, are alternatively pressed onto the surface of the bale.In addition to the fact that in this way the apparatus is rendered more expensive and elaborate, the ridges on the surface of the bale cannot be removed satisfactorily and rapidly, as the pins do not engage directly on these ridges and it cannot be reliably ensured that these ridges, or parts thereof, are torn away by the fibrous material which has been removed from the area adjacent the ridges.

Accordingly, it has already been proposed to shift the grid and the plucking roller laterally relative to the bale of fibres, after each removal of material from the bale or during this removal of material from the bale (US-PS 4281437).

This known apparatus enables the pins or teeth of the plucking roller directly to engage the ridges of material on the bale, and to remove these ridges, but this apparatus is of a considerably complicated and expensive nature.

The object underlying the present invention is, therefore, that of providing an apparatus which is of the type defined at the outset of this specification and which enables, in a simple fashion, material to be uniformly removed from the whole width of the bale of fibres without the formation of any ridges on the surface of the bale.

A further object underlying this invention is that of holding down the material over the whole width of the bale in a uniformly satisfactory manner.

This object is intended to be achieved by arranging that the free end of the restraining device, which extends in the direction of the point at which material is removed from the bale, lies outside the impact or working circle of the plucking roller. In this way, firstly, the fibrous material is efficiently held down and, secondly, it then becomes possible for the pins or teeth to be so arranged on the plucking roller that they remove fibrous material from the surface of the bale completely, that is to say without gaps.

Conveniently, the restraining device extends so far in the direction of the point at which fibres are removed that the free end of this restraining device lies on the bale in an area defined by two vertical planes, one of these vertical planes lying at a tangent to the impact circle of the plucking roller, and the other of these two planes passing through the centre of the plucking roller. For enabling this restraining device to accommodate to differing levels of the bale surface, the restraining device consists of individually movable elements.Due to the provision of the individually movable elements each portion of the surface of the bale acted on by these movable elements is subjected to a uniform pressure, so that the manner in which the fibrous material is restrained over the whole width of the bale is uniformly satisfactory, and it is ensured, with a high degree of reliability, that clusters of fibres will not be torn away from the bale.

In the case of a particularly simple form of construction the restraining device consists of leaf springs. A further expedient for ensuring a simple form of construction of the restraining device consists in mutually spacing the leaf springs. In accordance with another form of construction the restraining device consists of rigid, spring loaded bars. By limiting the pivoting range of the restraining device by stops, the force with which the restraining device presses against the fibre material is restricted to predetermined limits and, also, it is ensured that the restraining device will not pivot so far in the direction of the plucking roller that the free end of the restraining device comes into contact with the tips of the roller teeth.

It is possible to remove material from the surface of the bale fibres by means of a relatively small number of pins or teeth by arranging the pins or teeth in rows which extend helically round the axis of the plucking roller.

Embodiments of the invention are described below with reference to the accompanying drawing, in which: Figure 1 is a side view of a plucking roller, with a restraining device arranged outside the impact (contact) circle of the plucking roller; Figure 2 is a front view of a restraining device consisting of leaf springs; Figure 3 illustrates a plucking roller with a row of teeth which extends helically round the axis of the plucking roller; Figure 4 is a perspective view of a restraining device consisting of spring loaded bars.

Figure 1 shows a plucking roller 2 which lies above a bale 1 of fibres and is equipped with teeth 20, or with pins, studs or the like. The plucking roller 2, which serves as a device for the removal of material and is driven in the direction of the arrow P by a motor (not shown), is, in a known manner, rotatably mounted in a housing 3, and can travel with this housing 3 along the fibre bale 1 or along a row of such bales of fibres. In the housing 3, two driven toothed rollers 4 and 5 are also mounted. These extend axially parallel to the plucking roller 2 and press into the surface of the bale of fibres.

Associated with the plucking roller 2 is a restraining device 6, which presses downwardly the layer of fibres in the vicinity of the plucking roller 2, and in this way ensures that parts of this fibre layer will not be torn out during the process of removing the material. The restraining device 6 is fixed at one of its ends to a pivot pin 7, which is mounted for swivelling movement without the housing 3 and extends substantially parallel to the plucking roller 2. This restraining device 6 extends from the pivot pin 7 in the direction of the point A at which fibres are removed, although only for a distance such that the free end 60 of the restraining device 6 abuts the bale 1 of fibres at a point outside the impact circle S of the plucking roller 2.It suffices, for the required restraining action, if the free end 60 rise (as is shown in Figure 1) in an area which is delimited by a vertical plane V, which is tengential with the impact circle S, and a vertical plane V' passing through the centre of the plucking roller 2, preferably however in the last third portion of this area (as considered in the direction of rotation V of the plucking roller).

A tension spring 8, which engages a lever arm 9 which is attached to the rotatable pin 7, presses the free end 60 of the restraining device 6 onto the surface of the fibre bale. Adjustable stops 90 and 91 determine the range of swivelling movement of the lever arm 9, and hence that of the restraining device 6. It is possible, by suitably adjusting the stop 90, to determine and limit the force with which the restraining device 6 holds down the fibrous material, whereas the stop 91 ensures that the free end 60 of the restraining device will not come into contact with the tips of the teeth 20 as a result of external influences.In order to increase the area of contact of the restraining device 6 on the fibre bale, this device 6 is, at least in the area of its free end 60, convexly curved in the direction of the fibre bale; or the end of the restraining device 6 may be correspondingly bent, so that it lies approximately parallel to the surface of the bale of fibres. The tension spring 8 may be replaced by another device for biasing the restraining device, for example by an hydraulic biasing device.

The restraining device is preferably formed from a row of elements which are individually movable, so that these elements can accommodate to the different levels of the bale surface (the bale surface is usually irregular). In one simple form of construction these elements are in the form of leaf springs 61 which, mutually spaced, are fixed on the pivot pin 7 (Figure 2). Also, the leaf springs 61 may possibly be juxtaposed without mutual spacing. Other forms of construction of the restraining device 6, are, however, possible. For example, the restraining device may consist of rigid bars, which are curved or bent at their free ends, these rigid bars being fixed to the swivel pin 7 and being pressed, by the spring 8 against the surface of the bale of fibres or - and this is preferred -- may be individually movable.As shown in Figure 4, the bars 62 are individually pivotably mounted on a swivel pin 70; each ot these bars 62 can be pressed, at its free end, onto the bale of fibres by a respective tension spring 81. In this way, the bars 62 can individually accommodate the different levels of the irregular surface of the fibre bale. In each case it will be convenient if the restraining device 6 is positioned (in the direction of rotation P of the plucking roller 6) before the point A at which material is removed from the bale, so that the device 6 does not prevent fibre tufts, which have been removed from the bale, being thrown off and discharged through a suction tube 30.

As the restraining device 6 lies outside the working range of the plucking roller 2, this device 6 has no effect on the disposition of the pins or teeth 20 on the plucking roller 2. The teeth 20 are, therefore, juxtaposed so close to one another that, during each working stroke of the plucking roller 2 in the direction of the arrow P 1 , they remove fibrous material from the whole of the bale surface, no raised portions or ridges of fibrous material being left behind on the surface of the bale. It is not absolutely mandatory that the teeth 20 be juxtaposed without mutual spacing. The teeth 20 may be mutually spaced in the longitudinal direction of the plucking roller; however, this spacing must not be so great that fibrous material will not be entrained between two adjacent, spaced teeth. Further, the rows of teeth may be disposed in any desired way. In one example, which requires a relatively small number of teeth 20 and is therefore preferred, the teeth 20 form rows which extend helically round the axis of the roller (Figure 3).

The invention has been described with reference to a plucking roller which is mounted in a housing which can travel along the bale.

Naturally, however, the housing may also be stationarily arranged, the fibre bales being moved relative to the plucking roller.

Claims

1. Apparatus for opening fibre bales, with a plucking roller which acts on the bales from above, and with a restraining device which is associated with the plucking roller and is pivotably mounted, this restraining device resting on the bales and extending along the plucking roller for the whole working width of the latter, wherein the free end of the restraining device, which extends towards the point at which material is removed from the bale, lies outside the impact circle of the plucking roller.

2. Apparatus according to claim 1, wherein the free end of the restraining device lies on the bale over an area defined by two vertical planes, one of these planes lying at a tangent to the impact circle of the plucking roller, and the other of these planes passing through the centre of the plucking roller.

3. Apparatus according to claim 1 or claim 2, wherein the restraining device consists of individually movable elements.

4. Apparatus according to any of claims 1 to 3, wherein the restraining device consists of leaf springs.

5. Apparatus according to claim 4, wherein the leaf springs are mutually spaced.

6. Apparatus according to any of claims 1 to 3, wherein the restraining device consists of rigid, spring loaded bars.

7. Apparatus according to any of claims 1 to 6, wherein the range of pivotal movement of the restraining device is limited by stops.

8. Apparatus according to claim 1, wherein rows of pins or teeth are arranged on the plucking roller, and extend helically round its axis.

9. Apparatus for opening fibre bales and constructed substantially as hereinbefore described with reference to, and as shown in, the accompanying drawing.