JP5080399B2 - Centralizer device - Google Patents

Description

  The present invention relates to a down-the-hole drill having a mast device that is supported by a carriage so as to be raised and lowered, and more particularly to a centralizer device that guides a down-the-hole hammer of this type of down-the-hole drill so as to be slidable and rotatable.

  This type of down-the-hole drill is provided with a rotary head that can be moved forward and backward while being guided by the mast device. A rod is screwed to the tip of the rotary head, and a down-the-hole hammer is screwed to the tip of the rod. The rotary head transmits the rotational force generated by the built-in rotating mechanism to the down-the-hole hammer via the rod, and the down-the-hole hammer transmits the shock wave generated by the built-in striking mechanism to the tip bit. (For example, refer to Patent Document 1).

  This type of down-the-hole drill has a structure in which the rod diameter is thicker than that of a top hammer type crawler drill and a striking mechanism is arranged at the tip of the rod. For this reason, although it is assumed that the hole bending is relatively small, if the hole length is long, even a slight hole bending will result in a large hole error. Therefore, this type of down-the-hole drill is provided with a centralizer device as illustrated in FIGS. 5 and 6 at the tip of the mast device, thereby guiding the down-the-hole hammer so as to be slidable and rotatable.

  As shown in FIGS. 5 and 6, the centralizer device 90 includes a centralizer 100 that restricts the bending of the hole, and a rod clamp device 17 and a loosening device that have an opening / closing mechanism for adding and separating the rod 7. 20 is provided. The rod clamp device 17 includes a clamp cylinder 18 and a vise 19 as an opening / closing mechanism, and the loosening device 20 includes a clamp cylinder 21, a vice 22 and a swing cylinder 23 as an opening / closing mechanism.

In the centralizer 100, a bush 110 is fixed to the frame 130 disposed at the most advanced position of the centralizer device 90 with bolts 120. The bush 110 has an inner diameter dimension that is suitable for restricting the outer diameter of the down-the-hole hammer 6 so as to be slidable and rotatable. The reason for guiding the outer diameter of the down-the-hole hammer 6 by placing the centralizer 100 at the forefront of the centralizer device 90 is that during the counterboring hole process (state shown in FIG. 5) that is most likely to occur. This is because the object is held at a position as close as possible to the place where the vibration occurs.
JP 2007-239195 A

  Incidentally, as shown in FIGS. 5 and 6, the outer diameter of the down-the-hole hammer 6 is larger than the outer diameter of the rod 7. Therefore, the rod 7 cannot be regulated by the bushing 110 in the drilling step (the state shown in FIG. 6). It is expected that if the drilling process can be performed without shaking in the counterboring process, the subsequent drilling process can perform drilling with high accuracy by the self-guide function by the down-the-hole hammer 6 itself. Because.

However, in recent work sites, the height of a bench to be excavated at a time tends to increase, and the length of the drilling hole is further increased accordingly. Therefore, in the conventional drilling hole that relies on the self-guiding function, there is a possibility that the error in drilling accuracy may increase, and it is necessary to regulate the rod 7 not only in the counterboring hole process but also in this drilling process. It was pressed.
Here, as a measure for regulating the rod 7 in the drilling step, for example, a second centralizer having a bush having a size suitable for regulating the rod 7 so as to be slidable and rotatable with respect to the outer diameter of the rod 7 is used. It is conceivable to provide it. When such a second centralizer is provided, it is desirable that the arrangement location is the tip of the mast device in order to perform more effective anti-shake without sacrificing the stroke of the rotary head. .

However, if such a second centralizer is simply arranged immediately after the loosening device 20 (directly above in the figure), for example, there is a problem that it interferes with the down-the-hole hammer 6 at the time of counterboring holes. . Further, in order to eliminate the interference with the down-the-hole hammer 6, if the second centralizer is provided with an opening / closing mechanism using an actuator such as the rod clamp device 17 or the loosening device 20, the cost increases. Moreover, it is not preferable because the weight of the mast device increases. Furthermore, if the down-the-hole hammer 6 is pulled up with the second centralizer opening / closing mechanism closed, the opening / closing mechanism may be damaged.
Therefore, the present invention has been made paying attention to such problems, and can regulate the rod at low cost without using a special actuator, and slides and rotates both the down-the-hole hammer and the rod. An object of the present invention is to provide a centralizer device that can be guided as possible.

  In order to solve the above-described problems, the present invention provides a centralizer device that is disposed in a mast device that is supported by a cart so as to be raised and lowered, and that guides the down-the-hole hammer of a down-the-hole drill, and is arranged at the tip side of the mast device. A first centralizer configured to guide the down-the-hole hammer so as to be slidably rotatable, and a first centralizer disposed behind the first centralizer to support the down-the-hole hammer so as to be slidably rotatable. The second centralizer has a bush for guiding the rod so as to be slidably rotatable. The bush is divided into a plurality of parts, and the bushes divided into the plurality are rotated. The rotating mechanism supports the divided bushes from horizontal to upward when the mast device is in a standing state. It is characterized by being pivotally supported so as to permit rotation.

  According to the centralizer device of the present invention, since the first centralizer for guiding the down-the-hole hammer so as to be slidable and rotatable is provided, the down-the-hole is used by the first centralizer in the counterboring hole process as in the prior art. The outer diameter of the hammer can be guided so as to be slidable and rotatable. At this time, the second centralizer is supported by a down-the-hole hammer because the bushes divided into a plurality are pivotally supported by a turning mechanism that allows the mast device to turn upward from the horizontal. When the bushes divided into a plurality of parts are pushed up, the bushes divided into a plurality of parts are rotated upward to avoid interference with the down-the-hole hammer.

  And in this drilling step, the second centralizer has a plurality of bushes that are supported by a pivoting pivot mechanism. Thus, the outer diameter of the rod can be guided so as to be slidable and rotatable. Further, in the drilling step, the first centralizer does not contact the rod.

  Therefore, according to the centralizer device according to the present invention, both the down-the-hole hammer and the rod can be guided so as to be slidable and rotatable. And since the 2nd centralizer mentioned above is the simple structure of supporting the bush divided | segmented into plurality with the rotation mechanism by a pivot, compared with the opening / closing mechanism of the said rod clamp apparatus or a loosening apparatus, it is special. The rod can be regulated at a low cost without using an actuator.

  As described above, according to the present invention, it is possible to regulate a rod at a low cost without using a special actuator, and to provide a centralizer device capable of guiding both the down-the-hole hammer and the rod so as to be slidably rotatable. be able to.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate. In addition, the same code | symbol is attached | subjected about the structure similar to the above-mentioned conventional centralizer apparatus.
FIG. 1 is a side view for explaining an embodiment of a down-the-hole drill equipped with a centralizer device according to the present invention.
As shown in the figure, this down-the-hole drill 1 is configured to have a dolly 2 that can travel and a mast device 4 that is supported by the dolly 2 so as to be raised and lowered. A rotary head 5 is attached to the mast device 4, and the rotary head 5 is guided by the mast device 4 and supported by a feed mechanism (not shown) so as to be able to advance and retreat.

  A rod 7 shown in FIG. 2 is screwed to the tip of the rotary head 5, and a down-the-hole hammer 6 shown in FIG. 2 is screwed to the tip of the rod 7. Further, the rotary head 5 incorporates a rotation mechanism (not shown), and the rotational force generated by the rotation mechanism is transmitted to the down-the-hole hammer 6 via the rod 7. The down-the-hole hammer 6 incorporates a not-shown striking mechanism, and transmits a shock wave generated by the striking mechanism to a bit 8 screwed to the tip of the down-the-hole hammer 6.

Here, the down-the-hole drill 1 includes a centralizer device 9 for guiding the down-the-hole hammer 6 and the rod 7 supporting the down-the-hole hammer 6 at the distal end portion of the mast device 4.
Specifically, as shown in FIGS. 2 and 3, the centralizer device 9 adds and separates the first centralizer 10 and the second centralizer 14 that restrict the bending of the hole, and the rod 7. A rod clamp device 17 and a loosening device 20 are provided. The rod clamp device 17 includes a clamp cylinder 18 and a vise 19 as an opening / closing mechanism. In addition, the loosening device 20 includes a clamp cylinder 21, a vise 22, and a swing cylinder 23 as an opening / closing mechanism.

  In the first centralizer 10, a bush 11 is fixed by a bolt 12 to a frame 13 arranged at the most advanced position of the centralizer device 9. The bush 11 has a size suitable for restricting its inner diameter to be slidable and rotatable with respect to the outer diameter of the down-the-hole hammer 6 (see FIG. 4B). The down-the-hole drill 1 may replace the down-the-hole hammer 6 depending on the work specifications. In such a case, the bush 11 is replaced in accordance with the outer diameter of the replaced down-the-hole hammer 6.

  On the other hand, the second centralizer 14 is disposed at the rear end of the centralizer device 9, that is, at a position immediately after the loosening device 20 (directly above in the drawing). The second centralizer 14 has a rotating bush 15 as a bush for regulating the rod 7. The rotating bush 15 is divided into a plurality of parts, and in the example of the present embodiment, it is divided into two parts left and right. The rotating bush 15 is slid relative to the outer diameter of the rod 7 so that the inner diameter of the bushing 15 can be regulated by the two bushings 15a, 15b facing each other in a horizontal position. The dimensions are suitable for restricting movement and rotation (see FIG. 4A).

  Furthermore, the rotating bush 15 is configured such that a pivot mechanism is supported by the bushes 15a and 15b, which are divided into left and right parts, supported by the pins 16 so as to be rotatable. When the mast device 4 is in the standing state and the force in the push-up direction is applied to the bushes 15a and 15b, the rotating mechanism rotates the bushes 15a and 15b divided into a plurality from the horizontal to the upward direction. When the movement is allowed (see FIG. 2) and no force in the push-up direction is applied to the bushes 15a and 15b, the plurality of bushes 15a and 15b return to their horizontal positions by their own weight (see FIG. 2). (See FIG. 3).

Next, a case where a drilling operation is performed using the down-the-hole drill 1 equipped with the centralizer device 9 will be described.
The drilling operation is divided into a counterboring process and a subsequent drilling process. In any process, a shock wave is generated by the striking mechanism of the down-the-hole hammer 6, a rotational force is generated by the rotary mechanism of the rotary head 5, and the shock wave and the rotational force are transmitted from the bit 8 to the rock mass R by the feed mechanism. Crush the bedrock R. Note that the flour that has been crushed in the drilling step is discharged to the ground surface through the space between the outer diameter of the rod 7 and the inner wall of the drilling hole by the exhaust that has driven the striking mechanism.

  The counterboring process is to form a guide for the drilling process, and punctures the surface of the unstable rock R. Therefore, it is necessary to work carefully while suppressing the impact force. Here, the centralizer device 9 has the first centralizer 10 that guides the down-the-hole hammer 6 so as to be slidable and rotatable. Therefore, in the countersinking hole process, as shown in FIG. The centralizer 10 can guide the outer diameter of the down-the-hole hammer 6 so as to be slidable and rotatable. At this time, the rotating bush 15 of the second centralizer 14 is pivotally supported so that the two divided bushes 15a and 15b can rotate upward from the horizontal when the mast device 4 is in a standing state. Therefore, it is pushed up by the down-the-hole hammer 6 and pivots upward, thereby avoiding interference with the down-the-hole hammer 6. Therefore, in the counterboring process, the down-the-hole hammer 6 held near the bit 8 by the first centralizer 10 can minimize shaking even during unstable counterboring. , Good countersink holes can be made.

  Then, in the subsequent drilling step, the rotating bush 15 of the second centralizer 14 is divided into the two divided bushes 15a and 15b, and the push-up force acts on the bushes 15a and 15b. When it is not, it is pivotally supported so as to return to the horizontal position by its own weight, so it returns to its horizontal position by its own weight and guides the outer diameter of the rod 7 so as to be slidably rotatable. As a result, in the drilling step, the rod 7 near the hole opening can be held by the second centralizer 14, so that the down-the-hole drill 1 is coupled with the self-guide function of the down-the-hole hammer 6, so It can be performed. Therefore, even in the drilling work with a long drilling length, the countersinking hole to the main drilling hole can be performed stably and a highly accurate drilling hole is possible. The first centralizer 10 does not come into contact with the rod 7 during this drilling step.

  As described above, according to the centralizer 9, both the down-the-hole hammer 6 and the rod 7 can be guided so as to be slidable and rotatable. The rotation mechanism of the second centralizer 14 has a simple structure in which the bushes 15a and 15b divided into a plurality are pivotally supported by the pins 16, so that the rod clamp device 17 and the loosening device 20 are opened and closed. Compared to the mechanism, the rod 7 can be regulated at a low cost without using a special actuator.

The centralizer according to the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, if the total length of the mast device 4 is sufficient, the pair of the first centralizer 10 and the second centralizer 14 is not changed unless the positional relationship between the first centralizer 10 and the second centralizer 14 is changed. A pair of the rod clamp device 17 and the loosening device 20 may be arranged behind the rear. Moreover, there is no problem even if the bushing 11 of the first centralizer 10 is divided.

  Furthermore, for example, in the above-described embodiment, each of the bushes 15a and 15b that are pivotally supported has been described as returning to the horizontal position by its own weight when the force in the push-up direction is not acting. The rotating bush 15 (each bush 15a, 15b) of the second centralizer 14 may be provided with a biasing means for biasing downward (for example, a torsion coil spring provided by being fitted around the pin 16). With such a configuration, the number of parts is increased as compared with the case where the rotating bush 15 is returned to the horizontal position by its own weight, but it is suitable for stabilizing the rotating operation and the horizontal posture.

It is a side view of a down the hole drill carrying a centralizer device concerning the present invention. It is a front view of the principal part of the centralizer apparatus shown in FIG. 1, The figure is the figure which showed the counterboring hole process. It is a front view of the principal part of the centralizer apparatus shown in FIG. 1, The figure is the figure which showed this drilling process. It is sectional drawing of a centralizer apparatus, The figure (a) shows the AA cross section in FIG. 3, The same figure (b) has shown the BB cross section in FIG. It is the figure which showed the counterboring hole process in the conventional centralizer apparatus. It is the figure which showed this drilling process in the conventional centralizer apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Down the hole drill 2 Bogie 3 Boom 4 Mast device 5 Rotary head 6 Down the hole hammer 7 Rod 8 Bit 9 Centralizer device 10 First centralizer 11 Bush 12 Bolt 13 Frame 14 Second centralizer 15 Rotating bush 16 Pin 17 Rod Clamping device 18 Clamp cylinder 19 Vise 20 Loosening device 21 Clamp cylinder 22 Vise 23 Swing cylinder R Rock

Claims (1)

A centralizer device that is disposed on a mast device that is supported in a undulating manner on a carriage and guides the down-the-hole hammer of a down-the-hole drill,
A first centralizer disposed on a distal end side of the mast device to guide the down-the-hole hammer so as to be slidably rotatable; and a rod disposed behind the first centralizer to support the down-the-hole hammer. A second centralizer for guiding sliding and rotation;
The second centralizer has a bush for guiding the rod so as to be slidable and rotatable. The bush is divided into a plurality of parts, and the bushes divided into the plurality are respectively supported via a rotation mechanism. And the pivoting mechanism pivotally supports each of the divided bushes so as to allow the pivoting from the horizontal to the upward when the mast device is in a standing state. apparatus.

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