This application is a §371 National Stage Application of International Application No. PCT/FI2008/050274, filed May 15, 2008, and claims priority under 35 U.S.C. §119 and/or §365 to Finnish Application No. 20075361, filed May 18, 2007.
The invention relates to an arrangement for employing a drill steel centralizer travelling on a feed beam of a rock drill machine, the arrangement comprising a feed cylinder for moving the drill machine in the drilling direction and back, at least one turning wheel mounted stationary in relation to the feed cylinder and a flexible feed member running around it and connected both to the drill machine and the feed beam, a drill steel centralizer mounted to travel on the feed beam and stationary in relation to the feed cylinder in the longitudinal direction of the feed beam and having a central opening for a drill rod, a transfer opening at the side of the central opening for transferring the drill rod to the central opening and away from it and means for closing the transfer opening during drilling, and pressure fluid channels for feeding pressure fluid in to and out of the pressure fluid chambers of the feed cylinder.
When using long drill rods, and especially in long hole drilling, a drill steel centralizer travelling on the feed beam is generally used to support the drill rods; the centralizer being located between the drill machine and the drill steel guide at the front end of the feed beam and travelling on the feed beam as the drill machine moves. To produce the feed and return movement of the drill machine, very often a feed cylinder is used that is connected to move a wire or chain connected to the drill machine carriage. A change in the length of the feed cylinder then produces the movement of the drill machine. In known structures the longitudinal movement of the feed beam produces a movement of twice the length for the drill machine with the same ratio for the rates of travel. Typically the centralizer in connected to move with the moving part of the feed cylinder, i.e. the cylinder tube or piston depending on the used solution. Generally the piston rod of the feed cylinder is at its end connected stationary in relation to the feed beam, and the cylinder tube moves to produce the feed movement.
In general a centralizer is used that has an opening at the location at which the drill rod is brought to the drill machine. A problem with this solution is that the drill rod at times slips away from the centralizer, which means that drilling must be stopped and the drill rod wrenched back to the centralizer.
It is an object of the present invention to provide an arrangement in which the opening of the centralizer can be automatically closed and correspondingly opened during the use of the drill machine in an easy and simple manner.
The arrangement of the invention is characterized in that the centralizer has a pressure fluid-operated actuator for closing the transfer opening, that a pressure fluid channel is connected from the feed cylinder chamber, to which pressure fluid is fed during drilling to move the drill machine in the drilling direction, to the actuator of the centralizer in such a manner that the pressure of the pressure fluid makes the actuator close the transfer opening.
An essential idea of the invention is that the centralizer has an actuator that closes the opening for bringing in and removing the drill rod during drilling. Another essential idea of the invention is that the pressure fluid-operated actuator is connected to the pressure fluid chamber of the feed cylinder so that when the drill machine feed is switched on, the pressurized medium in the pressure fluid chamber of the feed cylinder acts on the actuator and makes it transfer a dosing member to the opening.
The arrangement of the invention provides the advantage that the centralizer can be closed during drilling, which means that the drill rod cannot slip away. The closure also takes place automatically when the drill machine feed is switched on, whereby the user need not take care of it.
The invention is described in more detail in the attached drawings in which
a and 2b are schematic representations of an open and closed centralizer of rock drill equipment in the longitudinal direction of a drill rod.
a-5b are schematic representations of another embodiment of an open and closed centralizer of rock drill equipment in the longitudinal direction of a drill rod.
Inside the feed beam 1, there is a feed mechanism with a feed cylinder 7, turning wheels 8, and a flexible feed member 9. The flexible feed member 9 may be a wire, chain, or some other corresponding flexible and longitudinally sufficiently strong member. At its ends, the feed member 9 is typically connected stationary to the feed beam 1 by means of a bracket 1a, for instance, and it runs around the turning wheels 8. The flexible feed member 9 is further connected to the drill machine carriage 3 in the area between the turning wheels 8 or alternatively directly to the drill machine 2. An end of a piston rod 7a of the feed cylinder 7 is in a manner known per se connected to the feed beam 1 to be longitudinally stationary. When pressure fluid is fed to one end of a cylinder tube 7b of the feed cylinder, i.e. in the case shown in the figure, to the cylinder chamber on the drill steel guide 5 side, the cylinder tube 7b moves toward the drill steel guide 5 forcing the flexible feed member 9 to run around the turning wheels 8. As a result of this, the drill machine moves toward the drill steel guide at a rate that is twice the rate of the cylinder tube 7b. As the centralizer 6 is connected longitudinally stationary in relation to the cylinder tube 7b, the centralizer 6 correspondingly moves at half the rate of the drill machine and its position at approximately halfway between the drill machine 2 and drill steel guide 5 remains the same during the feed movement, during drilling, and during the return movement of the drill machine.
Differing from what is stated above, the feed cylinder 7 can be connected to the feed beam 1 in the opposite way so that the cylinder tube 7b is longitudinally stationary in relation to the feed beam and the piston rod 7a moves. In such a case, the centralizer and turning wheels are naturally connected to move with the piston rod 7a. The pressure fluid can then be led to the actuator 11 through the piston rod 7a and, if necessary, back again inside it.
a and 2b and 5a and 5b are schematic representations of an embodiment of the centralizer 6 as seen from the axial direction of the drill rod.
b is a schematic representation of the centralizer of
By way of example, the valve 15 is shown in such a manner that when it is in its idle position shown in
The actuator 11 may be either a single- or double-acting pressure fluid cylinder or some other single- or double-acting actuator, such as a pressure fluid motor.
In the above description and drawings, the invention is described by way of example only and it is not in any way restricted thereto. The closing member of the centralizer may be connected to move in a different manner with either a turning movement or linear movement. Further, the actuator may as described be single-acting so that its return movement is generated with a spring or the like, and the closing movement by feeding pressure fluid thereto. Alternatively, the actuator may be implemented as a double-acting actuator so that the effect of the pressure fluid on one feed cylinder chamber generates the closing movement and correspondingly in the other cylinder chamber the opening movement. The feed cylinder is above described in such a manner that the cylinder tube or piston rod is connected to the back end of the feed beam, i.e. stationary to the drill machine side end, whereby during the feed movement the piston pushes out of the cylinder tube and the total length of the feed cylinder increases. Feed may also be done in such a manner that the cylinder tube or piston rod is connected stationary to the front end of the feed beam, i.e. the drill bit side end. During the feed movement, the piston then pulls into the cylinder tube and the total length of the feed cylinder decreases. The cylinder chambers and connections between the actuator and cylinder chamber are then naturally selected in accordance with the invention.
Number | Date | Country | Kind |
---|---|---|---|
20075361 | May 2007 | FI | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/FI2008/050274 | 5/15/2008 | WO | 00 | 11/18/2009 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2008/142201 | 11/27/2008 | WO | A |
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3642075 | Wills | Feb 1972 | A |
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4207805 | Jonsson | Jun 1980 | A |
4537263 | Bjor | Aug 1985 | A |
4972911 | Rajakallio | Nov 1990 | A |
5701962 | Jantunen | Dec 1997 | A |
5884712 | Hakkinen | Mar 1999 | A |
5988298 | Cheng et al. | Nov 1999 | A |
7617884 | Rubie | Nov 2009 | B2 |
Number | Date | Country |
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1310629 | Nov 1992 | CA |
74778 | Nov 1987 | FI |
Number | Date | Country | |
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20100139941 A1 | Jun 2010 | US |