JPS61282587A - Underground drill - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an underground drilling machine, and more specifically, by displacing the position of a middle cylinder relative to a fixed cylinder, - retracting the main body of the drilling machine; This invention relates to an underground penetrating machine that can be switched into operation. This is used in the field of small-diameter propulsion methods that penetrate underground, for example, for underground pipe work.

[Prior art]

A safe and economical small-diameter propulsion method is being considered for promoting the undergrounding of cables and underground pipe work such as water supply and sewage construction projects, and underground penetrators are attracting attention for this purpose.

An underground drilling machine operates a blower using compressed air, which applies intermittent impacts to the main body of the drilling machine, and uses this force to penetrate underground. Several examples of underground drilling machines have been proposed, but in all of them, the impact force of the striker colliding with the inside of the tip of the drilling machine body advances the penetrating machine body, and the outer diameter of the main body is large. The hole can be penetrated.

When penetrating underground with such an underground drilling machine, if there is an obstacle that makes it impossible to advance or if the hole is to be stopped in a blind hole, it is necessary to move the underground drilling machine backward inside the hole. . The backward operation is performed by applying an impact force in the opposite direction to the forward movement to the main body of the perforating machine by means of a striking element. For this purpose, a fixed member is attached to the rear of the perforating machine body, and although it does not touch the fixed member during reciprocating motion during forward operation, it is designed so that the rear edge of the striker hits the fixed member with an impact during backward operation. There is.

For example, Japanese Patent Publication No. 54-25721 describes a self-propelled device in which the direction of impact can be switched by a striking element. In this example, by changing the front and back position of the sleeve that slides in the rear variable volume chamber formed at the rear of the striker, air is supplied and discharged appropriately from the rear variable volume chamber to which air is constantly supplied. The timing of communication with the front variable volume chamber can be varied.

This is because the repositioned sleeve changes the air passage position of the communication hole provided in the striker, but in order to move the sleeve and maintain its position, A screw-type rotation and stop mechanism is employed for the nut. A passage for supplying air to the rear variable volume chamber is formed inside the sleeve, and an air supply hose is connected to the rear end. Therefore, when rotating the sleeve in order to change the position of the sleeve screwed into the nut integrated into the main body of the piercing machine, the operator must twist the air supply hose to transmit the twist to the sleeve. There is. Even though a highly rigid air supply hose is used, if the hole-piercing machine is deep underground, the hose may be extending underground. Yes, the hose must be twisted considerably to rotate the sleeve. Moreover,
Since the hose remains twisted when the sleeve is moved, there is a problem that the hose is seriously damaged. Further, since the twisting operation requires time and effort, it takes time to prepare for the reversing operation, resulting in problems such as a significant decrease in work efficiency.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned problems, and its purpose is to be able to quickly and easily switch from a forward operating state to a backward operating state when reversing an underground penetrating machine; Moreover, it is an object of the present invention to provide an underground drilling machine that can increase the efficiency of the entire drilling operation without causing major damage or wear and tear to the components related to its operation.

[Structure of the invention]

The features of the underground penetrating machine of the present invention will be explained with reference to FIG. 1. Air is supplied to a rear variable volume chamber 4 formed at the rear of the striker 3 and a front variable volume chamber 5 that can communicate with the rear variable volume chamber 4. By doing so, it is an underground drilling machine that reciprocates the striking element 3 within the piercing machine main body 2, and has two striking element sliding parts 8A on which the inner wall of the rear variable volume chamber 4 slides in an airtight manner. 8B is formed, and a fixed cylindrical body 9 is provided which is fixed to the perforator main body 2 via the cylinder shoulder part 12 at the rear position of the striking element 3, and between the two striking element sliding parts 8A and 8B. A middle cylindrical body 1 having an air supply hole 16 that can communicate with an air hole 14 formed in a narrow body portion 10a.
5 is fitted so as to be slidable within the fixed cylinder 9, and a retreat position holding means 17 that can be bonded to the inner peripheral surface of the fixed cylinder 9 is provided at the front end of the middle cylinder 15. That's true.

[For production]

When the middle cylinder 15 inside the fixed cylinder 9 is pulled through the air supply hose 7, the front end of the middle cylinder 15 engages with the inner surface of the striker sliding part 8A by the retreating position holding means 17. Middle cylinder body 1
The relative positional relationship between the fixed cylinder 5 and the fixed cylinder 9 is changed, and the position thereof is fixed.

The air supply hole 16 of the middle cylinder body 15 is the striking element sliding portion 8A.

Since it communicates with the air hole 14 formed in the narrow body part 10a between 8B and
6. Air flows into the front variable volume chamber 5 from the air hole 14. The striker 3 retreats due to the difference in force acting on both chambers 8A and 8B, and its rear edge 3b collides with the one-cylinder shoulder 12 of the fixed cylinder 9. The impact force causes the drilling machine main body 2 to receive a retreating force, and the underground drilling machine 1 repeats a retreating operation within the hole it has penetrated to the entrance.

〔Example〕

Hereinafter, the present invention will be explained in detail based on examples thereof.

FIG. 1 is an overall sectional view of an underground drilling machine 1 to which the present invention is applied, in which a reciprocating striker 3 is interposed in a long cylindrical drilling machine main body 2. A rear variable volume chamber 4 forming a cylindrical space is formed at the rear of the striker 3, and a rear end edge 3b that slides airtightly with the piercing machine main body 2 is formed around the rear of the chamber. There is. A front variable volume chamber 5 is formed between the striker 3 and the piercing machine main body 2, that is, in the front part and around the striker 3, and both chambers 4 and 5 are filled with air that expands and contracts as the striker 3 moves. It is a room. The front variable volume chamber 5 and the rear variable volume chamber 4 can be communicated with each other through a communication hole 6 opened in a part of the rear peripheral wall of the striking element 3, and the front variable volume chamber 5 and the rear variable volume chamber 4 can communicate with each other through a communication hole 6 opened in a part of the rear peripheral wall of the striker 3. By supplying compressed air from the air supply hose 7 through the cylindrical body 15, the blower 3 can be reciprocated within the piercing machine main body 2.

In such an underground drilling machine 1, when the striker 3 reciprocates, there are two striker sliding parts 8A on which the inner wall of the rear variable volume chamber 4 mentioned above slides in an airtight manner.

A fixed cylindrical body 9 in which 8B is formed is provided.

In the illustrated example, this constant cylinder body 9 consists of a front cylinder body 10 and a rear cylinder body 11 that is fitted into the rear part of the front cylinder body and integrally connected. A cylindrical peripheral portion 12 is formed which is fixed to the piercing machine main body 1 at a rear position.

A number of atmospheric communication holes 13 are opened on the same circumference in this cylindrical peripheral part 12, and the cylindrical peripheral part 12 itself is connected to a screw 2b carved in a part of the inner peripheral wall of the piercing machine main body 2. They are attached by screwing together, and are fixed so as not to move when the underground penetrating machine 1 performs a drilling operation.

In the fixed cylinder body 9, the above-mentioned two striker sliding parts 8
A and 8B are large diameter parts, and a small diameter narrow body part 10a is formed between both sliding parts, and an air hole 14 is opened in a part of the body part 10a. The narrow body portion 10a supports a middle cylindrical body 15 connected to the air supply hose 7 so as to be able to slide and displace in an airtight manner.
is opened.

At the front end of the middle cylinder 15, there is a retreating position holding means 17 that can be engaged with and detached from the inner peripheral surface of the striker sliding part 8A of the fixed cylinder 9.
is provided. In this example, the retreated position holding means 17 includes a collar body 18 that is fitted onto and fixed to the tip of the middle cylinder body 15, and a spring 19 that biases the collar body forward. . The diameter of the collar body 18 is tightly fitted into and engaged with the inner circumferential surface of the striking element sliding portion 8A, and the spring 19 is engaged with the inner circumferential surface of the striking element sliding portion 8A. It has a function of applying force so that the cylinder body 15 does not engage with the fixed cylinder body 9.

Note that the spring 19 may be omitted depending on the situation,
Further, other known engaging/disengaging mechanisms may be used to constitute the retreating position holding means 17.

In an embodiment with such a configuration, the underground penetrating machine 1 can be operated as follows.

First, the forward movement of the underground penetrating machine 1 will be explained. The middle cylinder body 15 shown in FIG. 2 is positioned toward the front with respect to the fixed cylinder body 9, and the collar body 18 of the retreating position holding means 17 is removed from the striking element sliding part 8A, and the positional relationship is adjusted by the spring 19. Retained. In this state, communication between the air hole 14 and the air supply hole 16 is cut off, and the compressed air supplied from the air supply hose 7 is introduced into the rear variable volume chamber 4 through the passage 15a in the middle cylinder 15. As a result, the pressure within the rear variable volume chamber 4 increases, and the force causes the striking element 3 to move as if being rapidly pushed forward. When the tip of the striker 3 collides with the front inner surface 2a of the perforator main body 1 shown in FIG. 1, the perforator main body 1 advances underground due to the impact force. Penetrating machine body 1
Since it receives the surrounding ground pressure, it remains in its forward position when the impact force disappears, but the striking element 3 is repelled by the front inner surface 2a and retreats. Not only due to this repulsive force, but also due to the difference in the area of air pressure acting on the front and rear surfaces of the head 3a of the striking element 3 L)
The retreat of the striking element 3 is assisted by the aerodynamic force generated by this. That is, as the striking element 3 moves forward, the communication hole q is removed from the striking element sliding part 8A as shown in FIG. 3, and the air in the rear variable volume chamber 4 is led out to the front variable volume chamber 5. . When the striker 3 is moved back to the position shown in FIG. It is led out from the atmosphere communication hole 13 which is opened in the air. As a result, the pressure in the front variable volume chamber 5 drops to atmospheric pressure, and the striker 3 is moved again by the aerodynamic force acting in the rear variable volume chamber 4, which is continuously supplied with air and maintains a constant pressure. It moves forward and applies an impact force to the piercing machine main body 2.

Next, when the underground penetrating machine 1 which is in the forward operating state is to be operated backward, the operator should pull the air supply hose 7 extending from the rear of the underground penetrating machine 1 underground to the penetration port. And the 5th vi! As shown in J, the middle cylinder 15 is moved back relative to the fixed cylinder 9. A flange body 18 protruding from the tip of the middle cylinder body 15 fits into the inner circumferential surface of the striker sliding portion 8A against the elastic force of the spring 19. The engagement is tight, and the engagement force is set equal to or greater than the elastic force of the spring 19. In addition, when the collar body 18 can receive a rearward force due to the air pressure in the front variable volume chamber 4, the engaged state is maintained also by the pressing force. In this state, the air supply hole 16 of the middle cylinder 15
Since the positions of the respective holes are selected so that they communicate with the air holes 14 of the fixed cylindrical body 9, the air supplied to the rear variable volume chamber 4 flows through the air supply holes 16. The air is led out to the front variable volume chamber 5 through the air hole 14 and the communication hole 6 of the striker 3. The striker 3 moves backward as shown in FIG. 6 under the same aerodynamic force as the backward movement of the striker during forward movement. Due to the force of the retreat, the rear end edge 3b of the striking element 3 is pushed against the shoulder part 12 of the fixed cylinder body 9.
collide with The impact force causes the piercing machine main body 2 to receive a retreating force, and it retreats toward the penetration port within the hole that it has pierced. At this time, the communication hole 6 is removed from the striking element sliding portion 8B, and the air in the front variable volume chamber 5 is led out through the atmosphere communication hole 13. The pressure in the front variable volume chamber 5 drops to atmospheric pressure, and the aerodynamic force acting in the rear variable volume chamber 4 moves the striker 3 forward again. At this time, when the communication hole 6 reaches the narrow body part 10a (see FIG. 5), the air from the air supply hose 7 is led out to the front variable volume chamber 5 as described above, so that the striker 3 can be penetrated. No forward impact force is applied to the drilling machine body 2. Note that unless air is supplied to the underground penetrating machine 1 that has come out from the penetration port to the ground through the backward operation, air pressure will not act on the rear variable volume chamber 4, and the engagement of the backward position holding means 17 will naturally disengage. Alternatively, if the air supply hose 7 is pushed slightly into the perforator main body 2 to disengage it, the forward operation can be performed again.

〔Effect of the invention〕

As can be seen from the description of the embodiments above, the present invention is such that the inner wall of the rear variable volume chamber is airtightly slid onto the fixed cylinder which is fixed to the main body of the piercing machine through the cylinder circumference at the rear position of the striker. A fixed barrel is provided with a middle cylinder that forms two movable striking element sliding parts, has an air hole in the narrow body between the two striking element sliding parts, and has an air supply hole that can communicate with the air hole. It is fitted in the body so that it can be slid and displaced, and the front end of the middle cylinder body is provided with a retreating position holding means that can be engaged with and detached from the inner circumferential surface of the fixed cylinder body, so it is possible to perform underground drilling operations. A hole-piercing machine in a forward operating state can be switched to a retractable operating state with a simple and quick operation. In addition, the operation is a simple push-in operation, which avoids severe damage to components such as the air supply hose and short-term wear and tear. As a result, maintenance and inspection work is also required.

This simplifies the process and increases the efficiency of the entire drilling process.

[Brief explanation of the drawing]

Fig. 1 is an overall sectional view of one embodiment of the underground penetrating machine of the present invention, and Fig. 2 is a sectional view of the main part of the embodiment, in which the striker is in an intermediate position in the underground penetrating machine in the forward operating state. Fig. 3 is a sectional view when the striking element is applying a forward impact, Fig. 4 is a sectional view when the striking element is retracted, and Fig. 5 is a sectional view when the striking element is in the backward operating state. FIG. 6 is a cross-sectional view of the position where the striker starts to retreat inside the medium drilling machine, and FIG. 6 is a cross-sectional view when the striker is applying a backward impact. 2--piercing machine main body, 3--striker, 4--rear variable volume chamber, 5--front variable volume chamber, 8A, 8B-striker sliding part,
9-Fixed cylinder, 10a-Narrow body, 12-Cylinder circumference, 14
- Air hole, 15 - Middle cylinder body, 16 - Air supply hole, 17 - Retracted position holding means.

Claims (1)

[Claims] (1) Underground penetrating machine that reciprocates the striker within the main body of the penetrating machine by supplying air to a rear variable volume chamber formed at the rear of the striker and a front variable volume chamber that can communicate with the rear variable volume chamber In this step, two striker sliding parts are formed on which the inner wall of the rear variable volume chamber slides in an airtight manner, and a fixing member is fixed to the main body of the piercing machine via the cylinder shoulder at the rear position of the striker. A cylindrical body is provided, and the middle cylindrical body has an air supply hole that can communicate with an air hole formed in a narrow body between the two striking element sliding parts, and the middle cylindrical body is fitted so as to be slidably displaceable within the fixed cylindrical body. An underground penetrating machine characterized in that the front end of the middle cylinder is provided with a retreating position holding means that can be engaged with and detached from the inner circumferential surface of the fixed cylinder.