JPH063907Y2 - Reverse hit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a reverse hammering device for a rock drill, which transmits a reverse impact to the rod to facilitate pulling out of the rod.

[Conventional technology]

When drilling into bad rock, the bit may get into the cracks in the rock or the clay layer, making it difficult to pull out the rod. Therefore, in order to facilitate such pulling out of the rod, it is possible to adjust the play of the shank rod 2 in front of the shank rod 2 of the rock drill 1 (the same applies to the left and below in the figure) as shown in FIG. A bushing 3 is provided and an oil chamber 4 is formed in front of the bushing 3. When the rod is pulled out, play is eliminated by hydraulic pressure so that the piston 5 can hit the shank rod 2 forward, or a hitting device is hit. The rod holder is attached to the holder frame that is supported so that it can be displaced relative to each other and is hit in the opposite direction by the striking piston when the rod is pulled out, and the impact can be transmitted to the rod via the rod holder, making it easy to pull out the rod. A reverse striking device (Japanese Patent Laid-Open No. 61-95885) has been proposed.

[Problems to be solved by the device]

Originally, hitting the rod at the time of non-drilling is not preferable because it causes fatigue of the rod and causes loosening of screws and the like due to mechanical vibration. Therefore, it is desirable that the action such as the reverse hit is effectively performed in the shortest possible time.

However, since the above-described right hitting device hits the ball toward the front, it has little effect on pulling out, the impact force applied to the rod is large, and the life of the rod is shortened.

On the other hand, the above-mentioned reverse striking device that is hit to the rear side always operates when the rod is pulled out, so there is a problem that the holder frame is hit by the piston even when it is unnecessary.

This invention solves the above-mentioned problems, and it is possible to apply a rearward impact that is effective for pulling out only when necessary, making it easy to pull out the rod and improving the durability of the rock drilling machine. It is an object to provide a reverse striking device.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, in a reverse striking device of the present invention, a striking body to which a piston of a rock drill is applied in the opposite direction at the time of pulling out a rod, and a transmission body for transmitting the impact received by a non-striking body to a rod And a non-striking body is a striking piston that can be selectively displaced between a striking position and a non-striking position.

[Action]

With the above configuration, when pulling out is easy, wasteful reverse stroke is not performed by setting the hit piston to the non-hit position. When it is difficult to pull out, the impact piston is impacted by setting the impact piston to the impact position,
The impact is transmitted to the rod via the transmission body, which facilitates pulling out of the rod.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical cross-sectional view of a rock drill provided with a reverse hitting device according to an embodiment of the present invention.

The rock drilling machine 11 is basically constructed in the same manner as a conventionally known rock drilling machine, and a piston 13 is fitted in a cylinder 12, and the piston 13 reciprocates back and forth by a hydraulic drive mechanism. Is given. A front head 14, a front cover 15, and a front cap 16 are connected to the front of the cylinder 12, and a shank rod 18 is supported by a chuck bushing 17 and a front cap 16 mounted inside the front head 14. A chuck driver 20 having a gear 19 on the outer circumference is fitted between the front head 14 and the chuck bushing 17.
Rotation is provided by the drive gear 22 rotated by 1. A chuck 23 is fitted inside the front of the chuck driver 20, and the chuck 23 spline-engages with the shank rod 18 to transmit rotation.
A back head 24 is connected to the rear of the cylinder 12. 25 is a thrust washer.

The rock drill 11 is fixed on a carriage 26, and a housing 28 in which a hit piston 27 is inserted is fixed to the rear portion of the carriage 26. From the hydraulic power source 31 to the front and rear chambers 29 and 30 of the hit piston 27, the switching valve 3
2 are connected to switching pipes 33 and 34 for selectively displacing the hit piston 27 between a non-hit position and a hit position, and the switching pipe 34 on the rear chamber 30 side is hit by a hit. An accumulator 35 for preventing excessive pressure fluctuation is provided. 36 is a tank and 37 is a dust cover.

Front chamber 2 when drilling or when pulling out is easy and reverse stroke is not required
By supplying pressure oil to 9 and retracting the hit piston 27 to hold it in the non-hit position, the reverse hit is not performed. When it is difficult to pull out, the pressure oil in the front chamber 29 is discharged and the rear chamber 3
0 is supplied with pressure oil to advance the hit piston and hold it in the hit position. This position switching can be operated remotely. Here, the impacted piston 27 is impacted by the piston 13, and the impact is transmitted to the thrust washer 25 through the housing 28, the carriage 26, the front head 14, the front cover 15, and the front cap 16. When the rod is pulled out, a rearward thrust is applied to the rock drill 11, and the spline portion of the shank rod 18 abuts the thrust washer 25. Therefore, the shank rod 18 is impacted by the thrust washer 25. It is easy to pull out.

[Effect of device]

Since the reverse striking device of this invention is configured as described above,
It is possible to apply a rearward impact that is effective for pulling out to the rod only when necessary to facilitate pulling out of the rod and improve the durability of the rock drill and rod.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a rock drill equipped with a reverse hitting device according to an embodiment of the present invention, and FIG. 2 is an explanatory view of a conventional hitting device. In the figure, 11 is a rock drill, 12 is a cylinder, 13 is a piston, 14 is a front head, 15 is a front cover, 1
6 is a front cap, 25 is a thrust washer, 26
Is a carriage, 27 is a hit piston, and 28 is a housing.

Claims (1)

[Scope of utility model registration request] 1. A reverse striking device comprising a striking body to which a piston of a rock drill is striking in a reverse direction at the time of pulling out a rod, and a transmitting body for transmitting an impact received by the striking body to a rod. A reverse striking device wherein the striking body is a striking piston which can be selectively displaced between a striking position and a non-striking position.