JPH0530292U - Perforator - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] In a drilling machine that ejects fluid from the tip during drilling work, prevents muddy water and the like from flowing back into the fluid ejection path of the drilling machine when fluid is not ejected. .. [Constitution] A check valve 28 is provided at the tip of the fluid ejection passage.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a drilling machine for drilling holes in rock, ground, and the like.

[0002]

[Prior Art]

 In the construction of tunnels such as waterways, power lines, sidewalks, and roadways, it is necessary to carry out ground improvement such as ground injection as an auxiliary method for excavation of soft ground and soft-hard alternating ground. In this case, a hole is first drilled in the ground by an excavator, and then a hardening agent or the like is injected into the hole drilled. A drilling machine used for this type of drilling, for example, causes the tip bit to be driven by compressed air, and at the same time ejects compressed air from the opening at the tip to eject chestnut powder crushed by the air flow to the outside of the hole. I try to discharge it.

[0003]

[Problems to be solved by the device]

 In the above-mentioned conventional drilling machine, for example, when drilling the ground where groundwater exists, when the supply of compressed air is stopped in the middle of the drilling work, muddy water, slime, etc. flow backward from the opening at the tip and enter the drilling machine. It had the drawback of intruding. Once muddy water penetrates into the drilling machine, the work must be stopped and the drilling machine disassembled and cleaned each time, which significantly reduces work efficiency. The present invention has been made in view of the above circumstances, and an object thereof is to provide a perforator that prevents backflow of muddy water or the like and improves work efficiency.

[0004]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the boring machine according to the present invention has a bit at the tip, and in the boring machine in which a fluid ejection passage opening at the tip is provided, the tip of the fluid ejection passage is provided. A check valve was provided to prevent backflow from the opening to the fluid ejection passage.

[0005]

[Action]

 When the fluid is ejected, the check valve allows the fluid to be ejected, while when the fluid is not ejected, the check valve closes the fluid ejection passage to prevent the backflow from the outside into the fluid ejection passage.

[0006]

【Example】

 FIG. 1 is a vertical sectional view of a punching machine according to an embodiment of the present invention. As shown in FIG. 1, the back head 2 is screwed to the rear end of the outer tube 1, while the chuck 3 is slidably fitted to the front end of the outer tube 1 along the longitudinal axis direction of the outer tube 1. It is worn. A bit 5 having a tip 4 attached to the tip thereof is detachably screwed to the chuck 3.

A compressed air supply path 6 is formed in the center of the back head 2. A valve receiver 7 is fixed in the outer tube 1 adjacent to the back head 2, and a check valve 9 is pressed against a valve seat 10 of the supply passage 6 by a spring 8 held by the valve receiver 7. That is, when compressed air is not supplied, the check valve 9 closes the supply passage 6 of the back head 2, while when compressed air is supplied to the supply passage 6, the pressure of the air causes the spring 8 of the spring 8 to spring. The check valve 9 is moved against the force to open the supply path 6.

A valve seat 11 is fixed in the outer pipe 1 adjacent to the valve receiver 7, and a partition ring 12 is provided in the outer pipe 1 on the front end side of the valve seat 11 with a space therebetween. It is fixed. An inner cylinder 13 is fixed to the valve seat 11 and the partition ring 12 so as to bridge the valve seat 11 and the partition ring 12 to form a cylinder chamber 14. A piston 15 is slidably inserted in the cylinder chamber 14 in the longitudinal axis direction.

On the other hand, the valve receiver 7 is provided with a communication hole 16 that communicates the front and rear thereof. Further, the valve seat 11 is provided with supply holes 17 and 18, and one supply hole 17 communicates the front and rear of the valve seat 11, that is, the valve receiver 7 side and the inside of the cylinder chamber 14 with each other. The supply hole 18 connects the valve receiver 7 side and a port 19 provided on the side surface of the valve seat 11. A butterfly valve 20 is provided at the opening of both of these supply holes 17 and 18 on the valve receiving 7 side. The butterfly valve 20 is swingably attached to the valve seat 11, and the swinging operation causes the openings of the supply holes 17 and 18 to be alternately opened and closed.

A nozzle 21 that projects into the cylinder chamber 14 is formed in the center of the valve seat 11. On the other hand, a through hole 22 is formed in the center of the piston 15 along the longitudinal axis, and the nozzle 21 is projected and retracted in the through hole 22 by the movement of the piston 15. The tip end side of the piston 15 has a small diameter, and this small diameter portion is slidably fitted into the partition ring 12. The small diameter portion of the piston 15, the partition ring 12, and the inner cylinder 13 form a closed space 23, and the inner cylinder 13 is provided with a port 24 for communicating the space 23 with the outside of the inner cylinder 13. It is being touched. A gap 25 is formed between the inner cylinder 13 and the outer pipe 1, and the port 24 communicates with the port 19 of the valve seat 11 via the gap 25.

The tip end surface of the piston 15 faces the rear end surface of the bit 5 described above, and when the piston 15 moves in the tip end direction, the piston 15 strikes the bit 5. A through hole 6 is formed in the center of the bit 5 along the longitudinal axis, and the tip of the through hole 26 opens at the tip of the bit 5 to serve as an air outlet 27. The hole 26 and the through hole 22 of the piston 15 form an air jet passage.

A check valve 28 is provided at the tip of the through hole 26 of the bit 5 to prevent backflow from the air outlet 27 to the through hole 26. The check valve 28 includes a valve body 30 that engages with a valve seat 29 of the through hole 26, a spring seat 31 fixed to the bit 5, and a spring seat 31 held by the spring seat 31 to press the valve body 30 against the valve seat 29. It consists of a spring 32. When compressed air is not supplied, the valve body 30 closes the tip of the through hole 26, while when compressed air is supplied to the through hole 26, the pressure of the air causes the spring 32 of the spring 32 to spring. The valve body 30 is moved against the force to open the through hole 26.

In such a configuration, the back head 2 is connected to a boring rod (not shown), and compressed air is supplied from the supply passage 6 of the back head 2. The supplied air opens the check valve 9, passes through the communication hole 16, and enters the supply hole 17 or 18 on the side opened by the butterfly valve 20. Assuming that the supply hole 17 is open as shown in FIG. 1, air enters the cylinder chamber 14, moves the piston 15 toward the tip side, and hits the bit 5. This striking force is transmitted to the bedrock and crushes it.

On the other hand, when the piston 15 moves toward the tip side, the pressure in the void 23 increases, and the pressure is transmitted to the supply hole 18 through the port 24, the gap 25, and the port 19 to operate the butterfly valve 20. Let As a result, the butterfly valve 20 opens the supply hole 18 and closes the supply hole 17. Therefore, after that, the air passes through the supply hole 25, is supplied to the void 23 through the port 19, the gap 25, and the port 24, and moves the piston 15 to the rear end side.

When the piston 15 moves to the rear end side, the nozzle 21 fits into the through hole 22 of the piston 15 and closes it in the process. Then, the pressure in the cylinder chamber 14 increases with the movement of the piston 15, and the pressure is transmitted to the supply hole 17 to operate the butterfly valve 20 in the opposite direction to the above. Then, the butterfly valve 20 returns to the state of FIG. 1, and the above-described operation is repeated.

On the other hand, when the nozzle 21 is pulled out from the hole 22 of the piston 15, the air is opened from the cylinder chamber 14 through the through holes 22 and 26 forming the air ejection passage and opens the check valve 28. At the same time, it is injected forward from the injection port 27. The injected compressed air pushes the chestnut powder generated by the perforation through the perforator and the perforated wall to the outside of the perforation.

Here, when the supply of the compressed air is stopped to stop the perforation, the valve element 30 closes the through hole 26 by the spring force of the spring 32 of the check valve 28. Therefore, it is possible to prevent muddy water, slime, etc. in the drilled holes from entering the drilling machine through the injection port 27.

[0018]

[Effect of the device]

 As described above in detail with reference to one embodiment, according to the present invention, since the check valve for preventing backflow is provided at the tip of the fluid ejection passage, the fluid ejection is stopped during the drilling operation. In addition, muddy water does not flow back into the drilling machine and intrudes, and the drilling work that interrupts fluid ejection can be performed efficiently.

[0019]

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a punching machine according to an embodiment of the present invention.

[Explanation of symbols]

 1 Outer tube 3 Chuck 4 Bit 15 Piston 28 Check valve

Claims (2)

[Scope of utility model registration request] 1. A drilling machine having a bit at its tip and having a fluid jet opening at the tip thereof provided therein, for preventing backflow from the opening to the fluid jet at the tip of the fluid jet passage. A punching machine characterized by being provided with a check valve. 2. An outer tube, a chuck slidably attached to a distal end portion of the outer tube in a longitudinal axis direction thereof, a bit removably attached to the chuck, and a bit internally provided in the outer tube. A piston that strikes the rear end of the bit, a flow path of compressed air that drives the piston back and forth, an air ejection path that opens at the tip of the bit and guides the compressed air to the opening, and the air ejection path And a check valve which is provided at a tip portion of the check valve and prevents a backflow from the opening to the air ejection passage.