JPS603189Y2 - downhole hammer - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in a part of a hammer in a downhole drill for drilling underground holes.

Conventional downhole drills have a part of the pneumatic hammer that makes the bit hit back and forth at the bottom of the drill shaft that rotates on the ground side, and that part of the hammer has a built-in automatic valve to make the bit move back and forth. Because the mechanism was complicated, expensive, and prone to failure; ■The automatic valve was sophisticated, so water in underground holes,
They tend to stop working due to the intrusion of soil particles, and since they are suspended deep underground, they are prone to dry firing, and there is no mechanism in place to prevent this.

The conventional drill bit of this type was Utility Model 51-219.
Although the one described in the No. 2 publication is known, there is no mechanism to prevent the bit head from being hit dry, and the drawback (2) has not been solved.

The present invention aims to provide a downhole hammer that eliminates these drawbacks.

In this invention, a Ryogawa piston rod 3 is inserted into a cylinder chamber 2 formed in a hammer body 1, and the bit head is placed in a bit upper storage space 4 provided at a position of the hammer body 1 where it is struck by the lower end of the piston rod. A bit 6 having a wider width than the piston rod 3 is inserted into the bit 6 so as to be able to rise and fall freely, and an air chamber 8 is provided in the upper extension of the bearing portion 7 of the upper shaft portion of the piston rod 3, and the air chamber and the upper part of the cylinder chamber 2 are communicated with each other. Also, an air introduction passage 10 from an air introduction port 9 provided at the upper end of the hammer body 1 is connected to an opening 11 below the cylinder chamber and in the middle of the bearing part.
12, an exhaust port 13 is opened in the center of the cylinder chamber 2, and is communicated with the bit upper storage space 4 located below, and a slot 14 is provided slightly above the piston portion 3' of the piston rod. This relates to a downhole hammer provided with an exhaust passage 15 that communicates the slightly lower outer circumferential wall of the head 5 with the outside air side of the bit blade.

In addition, in the figure, 16 is a passage that communicates the upper part of the cylinder metal 2 with the air chamber 8, and 17 is the exhaust port 1 of the cylinder chamber 2.
3 and the bit upper storage space 4, an exhaust passage 1
8 beam chainer ring, 19 indicates an auxiliary passage.

In this device, as shown in the drawings, air is first introduced through the air inlet 9, passes through the air inlet passage 10, is introduced into the lower chamber of the cylinder chamber 2 through the opening 11, and the drawing piston rod 3 is lifted upward by the air pressure.

Until the middle of lifting, the air in cylinder chamber 2 is exhausted from exhaust port 1.
3. It is discharged from the blade part of the bit 6 via the exhaust passage 17, the upper bit storage space 4, and the exhaust passage 15.

If the piston rod 3 rises to the extent that the piston portion 3' of the piston rod 3 closes the exhaust port 13, the air in the cylinder chamber 2 will escape from the exhaust port 13 to the atmosphere side, and on the other hand, the air in the cylinder chamber 2 will escape from the opening 12 of the air introduction path 10 to the nusumi 14. High-pressure air is introduced above the cylinder chamber 2 and through the passage 16 into the air chamber 8 through the cylinder chamber 2, and acts to rapidly push the piston rod 3 downward, causing the piston rod 3 to descend while gaining speed. The head 5 of the bit 6 is struck by the lower end of the piston rod 3, and the bit 6 is struck downward.

Next, the bit 6 is struck and bounces back due to the reaction force from the ground, while the piston rod 3 returns to the state shown in the drawing, and after the above process, the piston rod 3 is lifted again and the reciprocating movement is repeated. be.

If the bit 6 is fired, the bit 6 remains downward, and the bit head 5 closes the lower opening of the exhaust passage 17, stopping the reciprocating movement of the piston rod 3.

As described above, according to the present invention, the cylinder chamber 2, the drawing piston rod 3, the air passage, and the air chamber 8 skillfully allow the piston rod 3 to reciprocate without an automatic valve, and the bit head 5 allows the exhaust passage 17 to move. Closing the system eliminates dry firing, and since the structure is simple, it has the effect of not becoming inoperable due to water or earth and sand.

[Brief explanation of drawings]

The drawing is a longitudinal sectional view of the downhole hammer of the present invention. 1: Hammer body, 2 cylinder chamber, 3: Piston rod, 4: Bit upper storage space, 5: Head, 6: Bit, 7: Bearing section, 8: Air chamber, 9: Air inlet, 10: Air introduction path, 11, 12: opening, 13: exhaust port, 14: slip, 15: exhaust path.

Claims (1)

[Scope of utility model registration request] The Ryokawa piston rod 3 is inserted into the cylinder chamber 2 formed in the hammer body 1, and the head 5 is expanded into the bit upper storage space 4 provided at the position of the hammer body 1 where it is struck by the lower end of the piston rod. In addition, an air chamber 8 is provided in the upper extension of the bearing portion 7 of the upper shaft portion of the piston rod 3, and the air chamber and the cylinder chamber 2
and an air introduction passage 10 from the air introduction port 9 provided at the upper end of the hammer main body 1 to the lower part of the cylinder chamber and in the middle of the bearing part.
In addition, an exhaust port 13 is opened in the center of the cylinder chamber 2 and communicates with the lower bit upper storage space 4. Furthermore, a slot 14 is provided slightly above the piston portion 3' of the piston rod, and the head 5 of the bit 6 This down hole hammer is provided with an exhaust passage 15 that communicates the slightly lower outer peripheral wall with the outside air side of the bit blade.