GB2258662A - Opening device for opening fibre bales - Google Patents

Description

opening device for opening fibre bales This invention relates to an

opening device for detaching fibre tufts from compressed fibre bales such as cotton or cellulose fibre bales or the like. The opening device includes an opener means that travels along the top face of the stationary fibre bales and detaches fibre flocks therefrom. The opener means has rapidly rotating opener (detaching) rollers which have opener elements, for example, toothed discs or needles that cooperate with a grid whose grid bars are situated between the opener discs or needles.

In a known opening device the parallel axes of the opener rollers are in a horizontal alignment with one another. During the forward and return passes the opener rollers penetrate the upper surface of the fibre bale to an equal depth during the detaching operation. The opener rollers rotate in opposite directions such that in the zone of the fibre bales the circumferential part of the opener rollers move towards one another. it is a disadvantage of these constructions that as the opener rollers travel in a given direction during the detaching operation, the two opener rollers remove different quantities of fibre tufts from the fibre bales (one opening roller rotates in the direction of travel and the other rotates oppositely thereto).

in British Patent Specification No. 8917596 (the content of which is incorporated herein by reference) there is disclosed an arrangement in which a pivotal height adjustment of the two opener rollers is provided; the rollers, however, are pivoted in a vertical plane as a unit, that is, no individual pivotal adjustment is 5 possible.

British Patent No. 946,333 discloses a fibre bale opening apparatus having a series of parallel-arranged opener rollers and further wherein the fibre bales are conveyed underneath the opener rolls. Each opener roller is individually vertically linearly adjustable. As viewed in the direction of relative displacement of the rollers with respect to the fibre bales, during operation each roller is at a higher level than the roller that follows it.

is It is an object of the invention to provide an improved opening device of the above-outlined type which enables more uniform fibre removal to be achieved and, in particular, which permits the oppositely rotated opener rollers to be so arranged that they simultaneously remove substantially identical fibre flock quantities from the fibre bales during opening passes in either direction of travel of the opener means while being of simple construction.

The invention provides an opening device for opening fibre bales, comprising an opener means that is movable to and fro across an upper surface of a fibre bale, the opener means comprising a housing; first and second toothed, parallel opener rollers accommodated in the housing; first and second pivot frames carrying the first and second opener rollers, respectively; a pivot shaft for pivotally securing the first and second pivot frames to the housing to provide for a pivotal notion of each pivot frame in a substantially vertical plane relative to the housing; and first and second setting devices articulated to the first and second pivot frames, respectively, and to the housing for exerting separately settable adjusting forces to the first and second pivot frames, whereby a height level of the opener rollers relative to one another is set for effecting penetration of the opener rollers into a top bale surface to different depths thereof during the opening operation.

The construction according to the invention is particularly advantageously adapted for a fibre flock removing operation in which the leading opener roller as viewed in the direction of travel of the bale opener is at a lower level than the trailing opener roller. Such a relationship ensures a deeper penetration of the leading roller into the fibre material than the trailing roller, so that the leading roller detaches a larger quantity of fibre flocks than if it were at the same level as the trailing roller. In arrangements in which the parallel axes of the leading and trailing rollers are in horizontal alignment with one another and the direction of rotation of the leading roller is such that, at the surface of the bale. the roller circumference is moving in a direction opposed to the direction of travel of the opener means, the leading roller detaches less material than the trailing roller and a deeper positioning of the leading roller enables the quantities detached by the leading opener roller on the one hand and the trailing opener roller on the other hand to be substantially equalised. By virtue of an individual adjustability of the two opener rollers substantially.full equalisation of the detached fibre quantities may be achieved.

Preferably, a distance between a location of articulation of the first setting device to the first frame and an axis of the pivot means for the first pivot frame is greater than a distance between the axis of the first opener roller and the axis of the pivot means for the first pivot frame. Preferably, a distance between a location of articulation of the second setting device to the second frame and an axis of the pivot means for the second pivot frame is greater than a distance between the axis of the second opener roller and the axis of the pivot shaft means for the second pivot frame. The pivot means preferably comprises a first pivot shaft supporting the first pivot frame and a second pivot shaft spaced from the first pivot shaft and supporting the second pivot frame. The pivot means is preferably located be- tween the vertical planes containing the axes of the first and second opener rollers and said first and second pivot frames are oriented back- to-back.

It is a further advantage of the invention that the lifting or suspension force needed for the setting device to hold the opener roller may be less than the weight of such opener roller in view of the force arm (torque) relationships between the weight of the opener roller and the suspension force of the setting device related to the pivotal axis of the pivot frame. In the opening device of the invention, the arrangement may advantageously be such that the adjusting forces to be applied by the setting devices are less than those that would be required if linear adjusting mechanisms were used.

One embodiment of the invention will be described in detail with reference to the accompanying drawing, in which there is shown a schematic side elevational view of a fibre-opening device having individually pivotable take-off rollers.

In the drawing there is illustrated a preferred embodiment of the invention which may be incorporated in a travelling bale opener (opening device), such as a BLENDOMAT BDT model, manufactured by TrUtzschler GmbH & Co. KG, M6nchengladbach, Germany. The fibre bales 1 are freely supported on the ground and are arranged in a series along which the bale opener trolley travels back and forth on rails (neither shown). The bale opener has a vertically shiftable opener means generally designated at DD, essentially comprising an opener housing 2, two grids 3 and 4 (each formed of a series of grid bars) articulated to the housing 2 at 3a and 4a, respectively, two rapidly rotating opener (detaching) rollers 5 and 6 - 6 as well as a suction duct 7 for removing, by a vacuum stream V, the fibre flocks detached from the upper surface of the fibre bales. During the fibre flock removing (detaching) operation, the opener means DD travels either in the direction A (forward pass) or in the direction B (reverse or return pass). The grids 3 and 4 are so arranged that their grid bars extend into the clearances between the axially spaced teeth 5a, 6a. of the disc series of rollers 5 and 6. The grids 3 and 4 engage the top face la of the fibre bales and thus constitute a hold-down device.

The direction of rotation of the opener rolls 5 and 6, designated with arrows C and D, is oriented inwardly in the zone of the upper face la of the fibre bales 1.

In operation, the opener means DD, together with the opener rollers 5 and 6 travels back and forth above the freely standing fibre bales 1 while the teeth 5a, 6a of the respective opener rollers 5 and 6 extend through the grid gaps defined by the grid bars of the grids 4 and 5 and penetrate into the fibre bale surface. The fibre flocks torn out from the upper face la of the fibre bales 1 are thrown inwardly by the opener rollers 5 and 6. The fibre flocks are immediately introduced into the vacuum stream V and conveyed thereby through the suction duct 7 and removed from the bale opener by the air stream in a known manner for further processing.

Each opener roller 5 and 6 has its own heightadjusting assembly generally designated at 10 and 11, - 7 respectively. The two height-adjusting assemblies 10 and 11 are of identical construction; in the description which follows, the height- adjusting assembly 10 will be explained in detail.

The opener roller 5 has a shaft 5b which is rotatably held in a pivot frame 12. The pivot frame 12 is secured to the housing 2 by a pivot shaft 13 for'pivotal notion in a vertical plane as designated by the doubleheaded arrow E. A setting device 14 is, at one end, pivotally secured to the housing 2 by means of an articulation 14a and is, at its other end, pivotally secured to the frame 12 by means of an articulation 14b. The setting device 14 may be a turn buckle-type assembly or it may comprise a power cylinder to exert an adjusting force and a holding force on the frame 12 along a line connecting the pivots 14a and 14b. The force is applied as a torque to the axis 13a of the pivot shaft 13; such torque is composed by the product of the force exerted by the setting device 14 and the shortest distance (arm) between the line along which the force is exerted by the setting device 14 and the axis 13a. Such distance equals the distance a between the axis of the articulation 14b and the axis 13a when the direction of the force exerted by the setting device 14 is p erpendicular to the line connecting 13a with 14b. Thus, by applying a pulling force on the frame 12 by the setting device 14, the frame 12 and thus the opener roller 5 is pivoted clockwise about the axis 13a to thus raise the opener roller 5. Conversely, a release of the holding force by the setting device 14 will cause the frame 12 and thus the opener roller 5 to pivot, by its own weight, counter- clockwise about the axis 13a resulting in a lowering of the opener roller 5. Thus, the force required of the setting device 14 to maintain the roller carrying frame 12 in balance may be less than the weight of the'opener roller: such force/weight relationship is essentially determined by the b:a ratio, where D_ is the distance between the axis 5c of the shaft 5b and the axis 13a of the pivot shaft 13.

The identically constructed adjusting assembly 11 is mounted in a mirror image fashion relative to the adjusting assembly 10 such that the pivot shaft 13 of the adjusting assembly 10 and the pivot shaft 15 of the adjusting assembly 11 are in an adjoining, side-by-side relationship, that is, the two adjusting assemblies 10, 11 are arranged back-to-back. The individual pivotal suspension of the two opener rollers 5, 6 ensures a sufficient free space therebetween for accommodating, for example, a toothed idling pressing roller (not shown) which extends parallel to the opener roller and which is supported by the housing 2. Such pressing roller penetrates with its teeth into the bale surface and assists the grids 3 and 4 in stabilising the fibre bales 1.

During operation, when the bale opener performs its forward opening pass while travelling in the direction A, - 9 the adjusting assemblies 10 and 11 are set in such a manner that the opener roller 6 is at a lower level than the opener roller 5. At the end of the forward opening pass, while the directions of rotation C and D of the opener rollers 5 and 6 remain the same, the adjusting assemblies 10 and/or 11 are switched such that the opener roller 5 will be at a lower level than the opener roller 6 so that the opener roller 5 penetrates deeper into the fibre bale than the roller 6 as the bale opener travels in the direction B during its reverse opening pass. Such a switching operation of the two adjusting assemblies 10, 11 may be effected from a central control of the bale opener. The individual, separate heightadjustability of the two opener rollers 5 and 6 makes it possible to set the height of the two rollers 5 and 6 relative to one another in such a manner that the distance of one roller from a horizontal reference plane which connects the axes of the two pivot shafts 13 and 15 is other than the distance of the other roller from that horizontal reference plane. This, in turn, allows the relative height position between the two rollers 5 and 6 to be adjusted such that a substantially full equalisation of the fibre flock quantities removed simultaneously by the two rollers 5, 6 is ensured.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

11 - !glaims 1. An opening device for opening fibre bales comprising an opener means that is movable to and fro across an upper surface of a fibre bale, the opener means compris5 ing (a) a housing; (b) first and second opener rollers accommodated in the housing, the opener rollers being rotatable about substantially horizontal roller axes spaced from one another in a travelling direction of the opener means, and the roller axes being orientated transversely to said travelling direction; (c) first and second pivot frames carrying said first and second opener rollers, respectively; (d) pivot means for pivotally securing said first and second pivot frames to said housing to provide for a pivotal motion of each said pivot frame in a substantially vertical plane relative to the housing; and (e) first and second setting devices articulated to the first and second pivot frames, respectively, and to the housing for exerting separately settable adjusting forces on said first and second pivot frames, so that the opener rollers can be so positioned relative to one another that each roller penetrates the upper surface of the bale to a different depth during the opening opera tion.

- 12 2. An opening device as claimed in claim 1, wherein a distance between a location of articulation of the first setting device to the first frame and an axis of the pivot means for the first pivot frame is greater than a distance between the axis of the first opener roller and the axis of the pivot means for the first pivot frame. 3. An opening device as claimed in claim 1 or tlaim 2, wherein a distance between a location of articulation of the second setting device to the second frame and an axis of the pivot means for the second pivot frame is greater than a distance between the axis of the second opener roller and the axis of the pivot shaft means for the second pivot frame. 4. An opening device as claimed in any one of claims 1 to 3, wherein the pivot means comprises a first pivot shaft supporting the first pivot frame and a second pivot shaft spaced from the first pivot shaft and supporting the second pivot frame. 5. An opening device as claimed in any one of claims 1 to 4, wherein the pivot means is located between the vertical planes containing the axes of the first and second opener rollers and said first and second pivot frames are oriented back-to-back. 6. An opening device for opening fibre bales comprising an opener means substantially as described herein with reference to and as illustrated by the drawing.