Mining or in situ disintegration of hard material – Hard material disintegrating machines – Sidewall-working
Reexamination Certificate
1999-09-17
2001-07-31
Bagnell, David (Department: 3673)
Mining or in situ disintegration of hard material
Hard material disintegrating machines
Sidewall-working
Reexamination Certificate
active
06267449
ABSTRACT:
FIELD OF THE INVENTION
The invention relates in general to mineral mining installations and, more particularly, to a guide arrangement for a drum-type mineral cutting machine usable, for example, in coal mining installations.
BACKGROUND OF THE INVENTION
In mineral mining installations it is well known to mount a drum-type cutting machine, such as a shearer, on a conveyor extending alongside a mineral, e.g. coal, face. The machine has a drive motor which rotates a toothed sprocket wheel which meshes with a stationary track, such as a chain, on the goaf side of the conveyor remote from the mineral face. As the sprocket wheel rotates the machine is driven back and forth above the conveyor to strip mineral from the mineral face with a rotating cutting drum and the conveyor then transports the mineral with a circulating scraper-chain assembly. To support and guide the machine a floor rail on the mineral face side of the conveyor supports running wheels whilst at the opposite goaf side the machine has vertically depending guide arms fitted with guide blocks which co-operate with guide projections slidably engaging in a guide rail supported on the conveyor. The guide blocks can clasp the guide rail substantially in the manner of a hook from above and/or below (see DE-PS 25 52 085, DE-PS 26 46 291, DE-OS 29 25 240).
In order to adapt the guide blocks to the course of the conveyor which is not normally horizontal, the guide blocks are mounted on the guide arms of the cutting machine so as to be pivotal in height to a limited extent by means of horizontal transverse bolts.
In order not only to provide compensation if the horizontal is not level, which is achieved by the pivotability of the guide block about a horizontal axis, but also to prevent jamming of the guide blocks when the conveyor does not extend exactly rectilinearly but adopts a curved course, for example if the individual conveyor pans snake, it is also already known additionally to make the guide blocks pivot around a vertical axis on the guide arm. Thus for this purpose the guide blocks according to DE-OS 196 33 491 are each provided with a vertical journal with which it is mounted so as to pivot rotatably to a limited extent in a journal socket on the guide arm. This known arrangement allows part rotation or pivoting of the guide block around a vertical as well as a horizontal axis in the manner of a universal joint so locking or clamping of the guide block and the guide rail can be substantially avoided. Nevertheless it has been found that, with the dimensions of the guide arm normally used, the forces occurring during cutting can barely be controlled with the known arrangement. Moreover, with a conventional material thickness of the guide arm of 120 mm and the necessary diameter of the vertical journal of 60 mm, there is a risk that the vertical bore on the guide arm will break out or deform and therefore will no longer be capable of holding the guide block with the necessary reliability.
A guide arrangement is known from DE-GM 68 02 117. In this arrangement a transverse bolt is held rigidly in the guide arm and tapers at the two outer ends projecting from the guide arm substantially frusto-conically to the ends. These frusto-conically converging portions of the transverse bolt are held in cylindrical bores in the guide block with ample play and, owing to their configuration, allow limited pivotability of the guide block relative to the guide arm of the cutting machine both vertically and horizontally. The disadvantage of this arrangement resides mainly in the fact that guide block and transverse bolt only make loose contact with one another in each direction and this results in enormously high wear of the components because the transverse bolt can only be applied after overcoming the play existing on the respectively opposed surface regions of the bores in the guide block during each change of direction of travel. A further disadvantage of this arrangement is that the guide block can move not only in the vertical direction and the desired horizontal direction transversely to the direction of travel of the cutting machine but also in a horizontal direction parallel to the direction of travel of the cutting machine. As a result, the guide projection can more easily become disengaged from the guide rail arranged on the conveyor and reliable guidance of the machine is no longer ensured.
SUMMARY OF THE INVENTION
It is an object of the invention to avoid the aforementioned disadvantages and to provide a guide arrangement of the type mentioned at the outset which ensures good vertical and horizontal guidance of the cutting machine without leading to unacceptably high wear in the connection region between the guide block and guide arm.
Another object of the invention is to avoid problems occurring as a result of the predetermined dimensions of the guide arms when using a separate vertical journal of the type known in the art.
In accordance with the invention an improved guide arrangement comprises a guide block which is pivotally connected on a guide arm of the cutting machine for movement around a horizontal and a vertical axis and co-operates with a guide rail arranged on the conveyor. The guide arm fits into a pocket on the guide block and is secured therein by means of a transverse bolt. A pivot journal head is formed at one end region of the transverse bolt and the head is received pivotally relative to the guide block around a vertical axis in a pivot journal socket in a lateral wall of the pocket. A horizontal guide in the other lateral wall of the pocket receives the other end region of the transverse bolt with lateral play.
With such an arrangement, the pivotability of the guide block around the horizontal axis transversely to the direction of travel of the machine is brought about by the transverse bolt which can be simply plugged into a bearing bore on the guide arm and is held rotatably and snugly therein. The pivotability around the vertical axis is brought about by the particular holding of the transverse bolt in the lateral walls of the pocket formed in the guide block. The end of the transverse bolt forming the pivot journal head of the transverse bolt is held rotatably around the vertical axis but otherwise substantially non-displaceably in the associated pivot journal socket, like a ball in a ball socket, whereas the other end of the transverse bolt can move to and fro in the direction of travel of the cutting machine in the horizontal guide. In contrast to the state of the art, the vertical pivot axis here does not extend through the guide arm of the cutting machine but is offset to the side of it. If the pivot journal socket is arranged on the goaf-side of the guide block in the vicinity of its guide projection, it is possible with the invention in a quite exceptionally advantageous manner to bring the vertical axis of rotation into close spatial proximity with the guide projection making guide engagement with the guide rail so that the constraining forces, which also occur with the articulated mounting of the guide block, between the conveyor and the cutting machine can be minimised.
The pivot journal head preferably comprises lateral guide faces which are curved convexly so that it can pivot freely in the pivot journal socket and therefore always has at least linear contact with one side of the pivot journal socket. The pivot journal head and the pivot journal socket are preferably flattened in each case on their upper and lower sides, in other words at the roof and floor planes to ensure that the transverse bolt cannot rotate around its axis in the journal socket itself and also to prevent pivoting around a horizontal axis parallel to the direction of travel of the machine.
The pivot journal socket can be provided on its underside with at least one outlet orifice through which fine dust entering the socket can be discharged.
The transverse bolt is expediently secured in the pivot journal socket by means of a securing element which particularly advantageously consists substantially of a locking element
Merten Gerhard
Meya Hans
Bagnell David
DBT Deutche Bergbau-Technik GmbH
Kreck John
Samuels Gauthier & Stevens
LandOfFree
Guide arrangement for a drum-type mineral cutting machine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Guide arrangement for a drum-type mineral cutting machine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Guide arrangement for a drum-type mineral cutting machine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2489353