GB2255949A

GB2255949A - "partial-cutting machine"

Info

Publication number: GB2255949A
Application number: GB9205111A
Authority: GB
Inventors: Helmut Brandenburg
Original assignee: AC Eickhoff GmbH
Current assignee: AC Eickhoff GmbH
Priority date: 1991-03-08
Filing date: 1992-03-09
Publication date: 1992-11-25
Also published as: GB9205111D0; DE4107434A1

Description

? 2 J, ) c: 11; ') 1 "Partial-cuttincf Machine" The invention relates to a

partial-cutting machine, such as those for driving drifts in mine or tunnel construction, with a frontal plate-like tractor shovel, which has a cavity emanating from its rearward end, into which projects the end of a continuous conveyor, such as for example, a chain or belt conveyor. Known partial-cutting machines are generally equipped with a caterpillar track and carry on their machine frame a liftable and lowerable and also laterally swivellable jib, on whose top end a rotating breaking-down tool, for example, a cutting drum or the like, is mounted. The broken- down material passes onto the platelike tractor shovel, from which it is pushed onto the conveyor with the aid of loading arms which rotate or carry out swinging movements. The conveyor conveys it on to the back of the partial-cutting machine, where it is usually ejected onto a linked conveyor means.

In partial-cutting machines provided with such loading equipment, the swift and complete removal of the material which is provided can occasionally present difficulties. The cause of this can lie in a sharply varying piece size and/or in variations of the quantity of material which is fed in per time unit. A further important prerequisite for rapid and optimal clearing of the material to the machine conveyor depends upon the utilisation of the available surface of the tractor shovel for the active loading 2 operation.

In one f orm of known partial -cutt-ing mar_h ne, two loading arms are provided for removing the material,' each of which is mounted as a twoarmed lever centrally on an axis which is fastened eccentrically to a disc which carries out a rotating movement. The rearward end of each loading arm is articulatedly connected to a single-arm lever, which at its free end is kept stationarily swivellable and f orms a type of knuckle joint with the loading arm. In each loading arm, the free part of the arm serves to shift the material in the direction of the conveyor. Loading arms of this type are also called Hummer shear loaders. During operation, essentially only the front section of the base surface of the tractor shovel which is available altogether is swept by the two loading arms, in which connection the material lying on the tractor shovel is only seized during the movement of the loading arm in the direction of the conveyor. The return movement is an empty movement on the other hand, in which even any material which has newly fallen onto the tractor shovel is moved away from the conveyor.

The object of the invention is to provide a loading appliance for a partial-cutting machine in an improved construction in which it is above all possible to be able to utilize the available surface of the tractor shovel for the active loading operation to a much greater extent than up to now and to be able to use loading tools in a construction which is simpler in regard to their design and their driving elements.

3 Accordingly this invention provides a partial-cutting machine provided with a frontal plate-11ke tractor shovel which has a rearward cavity into which the end of a continuous conveyor, such as a chain or belt conveyor, projects, the shovel being defined laterally and at the rearward end by high-standing guide plates, and wherein loading arms, which are movable parallel to the surface of the tractor shovel, are connected to a motorised drive for reciprocating swivelling movements of the loading arms, in which the loading arms alternately adopt a limit position which faces the front end of the conveyor, such that, in the vicinity of the frontal terminating edge of the cavity of the tractor shovel, a swivel shaft of a loading arm is arranged on each of its two sides, each loading arm is fixed at one end as a single-armed lever to one of the swivel shafts, and the swivelling angle of each loading arm is at least 1800.

The single-arm levers provided as loading arms can be of several designs. In a first design, each loading arm can have a sector-like layout widening from the swivel shaft, where, in the inner swivelling position, its rear longitudinal edge can run roughly parallel to the longitudinal axis of the conveyor. Furthermore, it is advantageous to allow the rear longitudinal edge to run out into an outwardly curved end section and to design the circumferential edge in accordance with a circular section which is centred on the appropriate swivelling axis.

In another advantageous specific embodiment, each 4 loading arm is designed as a straight beam whose length corresponds roughly to the width of the cavity of the tractor shovel. In this construction, the swivelling angle of one loading arm can amount to approximately 2700. If in the inner limit position the loading arm runs roughly parallel to the frontal terminating edge of the cavity, the outer limit position can in this way be placed so far that the loading arm runs roughly in the direction of the longitudinal axis of the conveyor and in the outer limit position is therefore immediately adjacent to the longitudinal edge of the cavity.

During the loading movement of the loading arm, namely during the movement in the direction of the inner limit position, the material lying on the surface of the tractor shovel is seized and pushed to the front end of the conveyor from the commencement of the swivelling movement. In the subsequent return movement also, material newly added by the loading arm is seized and fed via the side edge of the cavity to the conveyor. As a result of this shaping and spatial arrangement of the loading arms, a large part of the available surface of the tractor shovel can therefore be used for the active loading.

According to another development, the tractor shovel in the rearward area on both sides of the cavity and also the guide plates can be adapted to the contour of the circular path of movement of the free ends of the loading arms whilst giving adequate clearance.

The performance of the reciprocating swivelling motions of the loading arms is brought about here with simple swivel shafts, which pass through the tractor shovel in a bore from the underside and carry the inner end of one loading arm in a fixed connection at their outer end.

In order to drive the swivel shaft, directionreversible hydraulic or electric motors, in necessary with intermediate gearings, can advantageously be used, and the drive of the swivel shafts can just as well be produced by hydraulic cylinders, where, in one advantageous construction, a hydraulic cylinder acts in each case on the end of a common chain train, which is led over a toothed wheel of a swivel shaft.

Enlarging the tractor shovel beyond the standard width at its two sides also presents no difficulties, in which connection, one auxiliary loading arm in the form of a single-armed lever is arranged in the area of each enlargement, which feeds the material from the extended area to the swivelling area of the adjacent loading arm.

In a tractor shovel of a larger width than the standard width, loading discs of a known form can also advantageously be combined in each case with an outer loading arm. Here a rotating loading disc is arranged on each side of the conveyor in the central area of the tractor shovel. In the area of the outer enlargement is arranged in each case a loading arm in the form of a single-armed lever with an axis of rotation which is perpendicular to the tractor shovel, which lever carries out a reciprocating swivelling movement between an inner and an outer limit position, in which the 6 loading arm is roughly tangentially adjacent to the appropriate loading disc.

The invention may be performed in various ways and specific embodiments will now be described, by way of example, with reference to the accompanying drawings, in which:- Figure 1 shows a side view of a partial-cutting machine; Figure 2 shows a top plan view of a loading device in a first specific embodiment; Figure 3 shows a top plan view of a loading device in a further specific embodiment; Figure 4 shows a top plan view of a loading device with a tractor shovel which is laterally widened as compared with the standard width; and Figure 5 shows a top plan view of a loading device corresponding to Figure 4 with loading discs and loading arms.

The partial-cutting machine 1 rests with its machine body 2 against a caterpillar track 3. On the machine body 2 is mounted a forwardly extending jib 4, which is swivellable vertically and horizontally and has a rotating breaking-down tool 5 at its free end. Underneath the jib 4 extends a tractor shovel 6 which is connected to the machine body 2. The shovel pushes the broken-down material onto an endless conveyor 7 which conveys it on to the back of the partial-cutting machine 1.

The tractor shovel 6 with the load-ing arms can be 7 variously shaped. Figure 2 shows a first specific embodiment, and in this the tractor shovel 6.1 has a substantially rectangular layout with bevelled corners at the front. The surface 8 of the tractor shovel is defined on the longitudinal sides and at the rearward end as far as a central cavity 9 by high-standing guide plates 10 and 11. The cavity 9 encloses the front end of the conveyor 7, which is illustrated as a chain conveyor in the drawing.

In this construction the loading arms 12 are plate-like in design with a substantially sector-like layout, and at their rearward ends are connected to a swivel shaft whose axis 13 stands perpendicularly to the surface 8 of the tractor shovel 6.1. The drawing shows the left loading arm 12 in the inner swivel position and the right loading arm 12 in the outer swivel position; the swivelling angle is almost 180. During operation, the loading arms 12 carry out movements in mutually opposite rotational directions. The drive of the swivel shafts occurs in known manner from the underside of the tractor shovel 6.1.

In the inner swivelling position the rear longitudinal edge 14 of the loading arms runs roughly parallel to the longitudinal axis of the conveyor 7. The front longitudinal edge 15 forms an acute angle with the f ront edge of the cavity 9. The outer circumferential edge 16 of the loading arms 12 runs on an arc which is centred on the appropriate swivelling axis 13. At its free end the rear longitudinal edge 14 passes into an outwardly curved end section 17.

From the illustration in Figure 2, lt becomes clear 8 that each individual loading arm 12 performs active loading work during the to and fro reciprocating movement, a large part of the available surface 8 of the tractor shovel 6.1 being swept and therefore being usable for loading. The thickness of the loading arms 12 is selected according to the type of debris which is to be expected.

Figure 3 shows a modified construction of a tractor shovel 6.2, in which the narrow sides are straight and are designed in quadrant form at the rearward end. In this case also, the tractor shovel is defined at the sides by high- standing guide plates 10 and 11. In this construction, loading arms 18, each in the form of a straight beam, are used. Each of these beams at its inner end is fixed to a swivel shaft, the axes 19 of the swivel shafts being spatially arranged in front of the front edge of the cavity 9. The drawing shows the left loading-arm 18 in the inner swivelling position and the right loading arm 18 in the outer swivelling position; The swivelling angle of each loading arm is 2700. 20 In this construction also, the loading material is moved in the direction of the cavity 9 and therefore towards the conveyor 7, during the to and fro movement of the loading arms 18. The swivelling movements of the loading arms 18 also move in mutually opposite directions here. Each loading arm sweeps almost three quarters of the surface of the circumcircle of the swivelling movement. Two piston-cylinder drive units 20 are provided, whose piston rods 21 are connected at their ends by a chain train 9 22. Underneath the tractor shovel, a chain wheel 23 is fixed to each of the swivel shafts. The chain train 22, as illustrated in Figure 3, is led over the two chain wheels 23. The piston-cylinder units 20 are alternately driven in 5 order to drive the loading arms 18.

The tractor shovel 6.3 shown in Figure 4 corresponds in its basic construction in the central area to the tractor shovel of Figure 3 in a standard width. What is different is that the tractor shovel 6.3 is widened on both sides beyond the standard width and that an auxiliary loading arm 18.1 in the form of a single-armed lever is arranged in the area of each of the extensions. The same reference numbers as in Figure 3 are provided in Figure 4 for the coinciding components. The outer loading arms 18.1, just like the inner loading arms 18, carry out to and fro swivelling movements with a swivelling angle of almost 2700. The drawing shows the left loading arm 18.1 in the outer swivelling position and the right loading arm 18.1 in the inner swivelling position. The outer loading arms 18.1 serve to a certain extent to support the movement of material in towards the inner loading arms 18. Of the outer guide plates, the rearward guide plates 11 are adapted to the circumcircles of the paths of movement of the loading arms 18 and 18.1. The drives for the loading 25 arms 18 and 18.1 can be differently designed, for example, as single drives or common drives via suitable gearing elements. Figure 5 shows a modified construction of a tractor shovel 6.4 with a larger width than the standard width. In variance f rom the construction of Figure 4, loading discs 24 of known design are provided here in the inner area instead of loading arms.

On the surf ace of the loading discs 24 are arranged several curved shovels 25, which extend from the outer circumference towards the centre. The loading discs 24 rotate in the direction of the arrows shown. Outside the loading discs 24 is arranged one loading arm 18.2 in each case, corresponding to the loading arms 18.1 of the construction of Figure 4. Here also, the loading arms 18.2 during operation act to assist movement of material in towards the inner loading discs 24.

Claims

1. A partial-cutting machine provided with a frontal plate-like tractor shovel which has a rearward cavity into which the end of a continuous conveyor, such as a chain or belt conveyor, projects, the shovel being defined laterally and at the rearward end by high-standing guide plates, and wherein loading arms, which are movable parallel to the surface of the tractor shovel, are connected to a motorised drive for reciprocating swivelling movements of the loading arms, in which the loading arms alternately adopt a limit position which faces the front end of the conveyor, such that, in the vicinity of the frontal terminating edge of the cavity of the tractor shovel, a swivel shaft of a loading arm is arranged on each of its two sides, each loading arm is f ixed at one end as a single-armed lever to one of the swivel shafts, and the swivelling angle of each loading arm is at least 1800.

2. A partial-cutting machine as claimed in Claim 1, wherein the loading arms in each case have a sector-like layout widening f rom the swivel shaf t, wherein the rear longitudinal edge of each loading arm runs roughly parallel to the longitudinal axis of the conveyor in the respective inner swivelling positions.

3. A partial-cutting machine as claimed in Claim 2, wherein the rear longitudinal edge of the loading arm finishes in an outwardly curved end section.

4. A partial-cutting machine as claimed in Claim 2 or 12 Claim 3, wherein the circumferential edge of the loading arms in each case is formed as a circular segment which is centred on the appropriate swivelling axis.

5. A partial-cutting machine as claimed in Claim 1, wherein the loading arms are designed as straight beams whose length roughly corresponds to the width of the cavity.

6. A partial-cutting machine as claimed in Claim 5, wherein the swivelling angle of each loading arm is approximately 270.

7. A partial-cutting machine as claimed in Claim 5 or Claim 6, wherein the tractor shovel, in the rearward area on both sides of the cavity, and also the respective guide plate is adapted to the contour of the circular path of movement of the f ree f ront edge of the loading arm and is adjacent to this contour with clearance.

8. A partial-cutting machine as claimed in any one of Claims 1 to 7, wherein direction-reversible hydraulic or electric motors, if necessary with intermediate gearings, are used for driving the swivel shafts.

9. A partial-cutting machine as claimed in any one of Claims 1 to 7, wherein piston-cylinder units are used for driving the swivel shafts.

10. A partial-cutting machine as claimed in any one of Claims 1 to 7, wherein hydraulically or electrically driven swivel gears are used for driving the swivel shafts.

11. A partial-cutting machine as claimed in any one of Claims 1 to 7, wherein a common chain train, which acts on a toothed wheel of a swivel shaft in each case, and piston- 13 cylinder units which are connected in each case to one end of the chain, are used for driving the swivel shafts.

12. A partial-cutting machine as claimed in any one of Claims 1 to 11, wherein the tractor shovel is extended beyond the standard width on its two sides and that an auxiliary loading arm in the form of a single-arm lever is arranged in the area of each of the extensions.

13. A partial-cutting machine provided with a frontal plate-like tractor shovel, which has a rearward cavity into which the end of a continuous conveyor, such as a chain or a belt conveyor projects, the shovel being defined laterally and at the rearward end by high-standing guide plates, and wherein a rotating loading disc is arranged on each side of the cavity, the tractor shovel being extended beyond a standard width on its two sides and having an auxiliary loading arm in the form of a single-armed lever arranged in the area of each of the extensions, which arm carries out a reciprocating swivelling movement between inner and outer limit positions, in which the loading arm is tangentially adjacent to the circumferential edge of the appropriate loading disc.