JPH0349350B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a reversible underground penetrating machine, and more specifically, the present invention relates to a reversible underground penetrating machine. This invention relates to an underground penetrating machine whose main body can be switched from forward operation to reverse operation. This is used in the field of small-diameter propulsion methods that penetrate underground, for example, for underground piping work.

[Conventional technology]

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 either case, the impact force generated when the striker collides with the inside of the tip of the perforator main body causes the perforator main body to move forward, making it possible to pierce a hole with a large outer diameter of the main body.

When drilling underground with such an underground drilling machine, if there is an obstacle that makes it impossible to advance or if you want to keep the drilling in a blind manner, use the underground drilling machine inside the hole. need to be reversed. In the reverse operation, it is necessary to apply an impact force in the direction opposite to that in the forward movement to the main body of the perforator by means of the striking element. For this purpose, a fixing member is attached to the rear of the perforating machine body, and it does not hit the fixing member during reciprocating motion during forward operation, but during reciprocating motion during reverse operation, the rear end edge of the striker impacts the fixing member. It is considered that it corresponds to

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 position of the air passage of the communicating hole provided in the striker is changed due to the changed position of the sleeve. A threaded rotation and stop mechanism on a fixed nut is employed to move the sleeve and hold its position. 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, the sleeve must be rotated in order to change the position of the sleeve, which is screwed into the nut integrated into the body of the piercing machine. In this case, the operator twists the air supply hose and transmits the twist to the sleeve.

A highly rigid air supply hose is used, but when the hole-piercing machine goes deep underground, the hose has to extend long as it crawls underground. A significant twist must be applied to the hose in order to rotate the sleeve. Moreover, since the hose remains twisted in the state in which the sleeve is moved, there is a problem in that the hose is seriously damaged. Further, since the twisting work requires time and effort, it takes time to prepare for the reverse operation, resulting in a problem such as a significant decrease in work efficiency.

[Problem to be solved by the invention]

By the way, Japanese Unexamined Patent Publication No. 48-72001 describes a device that allows an underground penetrating machine to be switched between forward and reverse movement without the need to twist an air supply hose.

In this underground drilling machine, when switching from a state in which forward movement is possible to a state in which movement is possible in reverse, the intermediate cylinder for positioning the control cylinder is pulled with a rope to release the locked state between the intermediate cylinder and the control cylinder. In this state, the control tube is pulled rearward via the air supply hose, and the control tube is positioned and fixed again using the middle circumferential tube.

For this purpose, two balls placed at a distance are used, and the configuration to make them function is complicated. Moreover, the fixation by the ball after the switching operation cannot be said to be able to sufficiently withstand the vibrations generated by the striking element. Moreover, the operation of displacing the tube by means of the rope and the displacement operation of the control tube relative to the ball must be performed with respect to the ball, which cannot be seen from the outside. Therefore, there is a drawback that the reliability of the switching operation is impaired. Further, it is necessary to displace the intermediate cylinder via the rope and to displace the control cylinder via the air supply hose, which has the drawback of poor workability and complicating the switching operation.

The present invention has been made in view of the above-mentioned problems, and its object is to quickly and easily move an underground penetrating machine out of the forward operating state without twisting the air supply hose when reversing the underground drilling machine. It must be possible to switch to a state where reverse operation is possible, the structure of the structural parts related to the switching operation is simple, and the structure must not cause major damage or wear to each component, and it must be fixed after switching. To provide a reversible underground penetrating machine whose functions are not impaired during underground penetrating operation and whose set state is reliably maintained.

[Means to solve the problem]

The present invention supplies compressed 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 through an air supply hose, thereby moving the striker into the main body of the piercing machine. Applicable to underground penetrating machines that reciprocate.

Its characteristics are as shown in Figure 1.
It is equipped with two striker sliding parts 8A and 8B arranged at different positions in the front and rear, which slide airtightly against the inner wall of the rear variable volume chamber 4, and a striker sliding part at the rear of the striker 3. Through the cylinder shoulder portion 12 integrated at the rear position of 8A and 8B, the piercing machine main body 2
A fixed cylinder 9 is provided which is fixed inside. Narrow body portion 10 between the above-mentioned two striker sliding portions 8A and 8B
Air supply hole 1 that can communicate with air hole 14 formed in a
6, an air supply hose 7 is connected to the rear end, and a middle cylinder 15 is installed which is slidably fitted within the fixed cylinder 9.

It is attached to the front end of the middle cylindrical body 15, and is tightly fitted to the inner circumferential surface of the fixed cylindrical body 9 by the pulling action of the air supply hose 7, and is integrated with the fixed cylindrical body 9.
In addition, the fixed cylinder 9 is moved by the pushing operation of the air supply hose 7.
Reverse position holding means 17 that can be separated from the
is provided.

[Effect]

The middle cylinder 15 inside the fixed cylinder 9 is connected to the air supply hose 7
When pulled through, the front end of the middle barrel 15 engages with the inner surface of the fixed barrel 9 by the reverse position holding means 17, and the relative positional relationship of the middle barrel 15 with respect to the fixed barrel 9 is adjusted. Be changed. Fixation after the change is maintained by closely fitting the reverse position holding means 17 to the inner circumferential surface of the fixed cylinder 9.

The air supply hole 16 of the middle cylinder body 15 is connected to the striking element sliding part 8.
Air hole 1 formed in the narrow body part 10a between A and 8B
4, the air supplied through the middle cylinder body 15 flows into the front variable volume chamber 5 from the air supply hole 16 and the air hole 14.

The striker 3 moves backward due to the difference in force acting on both chambers 5 and 4, and its rear edge 3b collides with the cylinder shoulder 12 of the fixed cylinder 9. Due to the impact force, the piercing machine main body 2 receives a retreating force, and the underground piercing machine 1 moves backward through the hole it has penetrated to the entrance.

Note that if the air supply hose 7 is pushed back, the reverse position holding means 17 is disengaged from the inner circumferential surface of the fixed cylinder 9, and the underground penetrating machine 1 returns to forward operation.

〔Example〕

The present invention will be described in detail below 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. Striker 3
A rear variable volume chamber 4 forming a cylindrical space is defined at the rear of the chamber, and a rear edge 3b that slides airtightly with the piercing machine main body 2 is provided around the rear of the chamber. A front variable volume chamber 5 is located between the striker 3 and the piercing machine main body 2, that is, at the front and around the striker 3.
is formed, and both chambers 4 and 5 serve as air chambers that expand and contract as the striking element 3 moves.

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 the case of such an underground penetrating machine 1, the striking element 3
A fixed cylindrical body 9 is provided in which two striker sliding parts 8A and 8B are formed that slide airtightly against the inner wall of the rear variable volume chamber 4 when the striker reciprocates. In addition, the two impactor sliding parts 8A and 8B are as follows:
They are arranged at different positions in the front and back, and in this example, they are provided substantially in the front half of the fixed cylinder 9.

In the illustrated example, the fixed cylinder 9 is a front cylinder 10.
and a rear cylindrical body 11 that is fitted into the rear part of the cylindrical body 11 and integrally connected to the rear cylindrical body 11.
A cylindrical shoulder portion 12 fixed to the piercing machine body 1 is integrated at the rear of the striker 3.

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

In the case of the fixed cylinder 9, the above-mentioned two striking element sliding parts 8A and 8B form a large diameter part, and a narrow body part 10a with a small diameter is formed between the two sliding parts, and a part of it is formed with a small diameter body part 10a. Air holes 14 are opened. Its narrow body 10
a supports the middle cylindrical body 15 connected to the air supply hose 7 so as to be slidably displaceable in an airtight manner, and the middle cylindrical body 1
An air supply hole 16 that can communicate with the air hole 14 is opened at 5 .

A fixed cylinder 9 is attached to the front end of such a middle cylinder 15.
A removable reverse position holding means 17 is provided on the inner peripheral surface of the striking element sliding portion 8A. This reverse position holding means 17 is located at the front end of the middle cylinder 15,
When the air supply hose 7 is pulled, it is closely fitted to the inner peripheral surface of the fixed cylinder 9 and integrated with the fixed cylinder 9, and when the air supply hose 7 is pushed, it can be separated from the fixed cylinder 9. I'm starting to be able to do it. In addition, in this example, the reverse movement position holding means 17 is
The collar body 1 is fitted and fixed to the tip of the middle cylindrical body 15
8 and a spring 19 that urges it forward.
It is accompanied by

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 activated when the inner cylinder body 15 is pulled through the air supply hose 7. It has the function of exerting a force that prevents the middle cylinder 15 and the fixed cylinder 9 from engaging unless otherwise specified. Note that the spring 19 does not necessarily need to be provided depending on the degree of close fitting between the collar body 18 and the inner circumferential surface of the fixed cylinder body 9.

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 reverse movement position holding means 17 comes off the striking element sliding part 8A and is held in that position 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. Since the main body 1 of the perforator receives the surrounding ground pressure, it remains in its forward position when the impact force disappears, but the striker 3 moves forward from the front inner surface 2a.
I was repulsed by this and retreated. Not only due to this repulsive force, but also due to the aerodynamic force caused by the difference in the area of air pressure acting on the front and rear surfaces of the head 3a of the striking element 3.
Striker 3 is assisted in retreating. That is, the advancing striker 3 opens the communication hole 6 as shown in FIG.
is removed from the striking element sliding part 8A, and the front variable volume chamber 5
This is because the air in the rear variable volume chamber 4 is led out.

When the striker 3 moves back and comes to the position shown in FIG.
It is led out from the atmosphere communication hole 13 opened at 2. 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. Move forward and drill through the machine body 2
gives impact force to.

Next, when the underground penetrating machine 1 which is in the forward operating state is to be operated in reverse, the operator must connect the air supply hose 7 extending from the rear of the underground penetrating machine 1 underground to the penetration port. The inner cylinder 15 is pulled back with respect to the fixed cylinder 9 as shown in FIG. A flange body 18 protruding from the tip of the middle cylinder body 15 fits into the inner circumferential surface of the striking element sliding portion 8A against the elastic force of the spring 19. The engagement is close;
The engagement force is set equal to or greater than the elastic force of the spring 19.

Note that if the collar body 18 can receive force rearward due to the air pressure in the front variable volume chamber 4,
The engaged state is also maintained by the pressing force. In this state, the positions of the air holes 16 of the middle cylindrical body 15 and the air holes 14 of the fixed cylindrical body 9 are selected so that they communicate with each other, so that the air supplied to the rear variable volume chamber 4 is , air hole 16, air hole 1
4 and the communication hole 6 of the striking element 3 to be led out to the front variable volume chamber 5. 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.

The rear end edge 3b of the striker 3 collides with the cylinder shoulder portion 12 of the fixed cylinder body 9 due to the force of the retreat. Due to the impact force, the piercing machine main body 2 receives a reverse force, penetrates the hole itself, and moves backward inside the hole toward the penetration port. 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 inside the front variable volume chamber 5 drops to atmospheric pressure,
The striking element 3 is moved forward again by the aerodynamic force acting in the rear variable volume chamber 4.

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 penetrates. No forward impact force is applied to the drilling machine body 2. In addition, unless air is supplied to the underground penetrating machine 1 that has come out of the ground from the penetration port by performing reverse operation, air pressure will not act on the rear variable volume chamber 4, so that the reverse position holding means 17 cannot be locked. If it comes off naturally, or if the air supply hose 7 is pushed slightly into the perforating machine body 2 to release its lock, it can be operated forward again.

[Effects of the Invention] As can be seen from the description of the above embodiments, the present invention has the following advantages:
Two striking element sliding parts on which the inner wall of the rear variable volume chamber slides in an airtight manner are formed on a fixed cylindrical body that is fixed to the main body of the piercing machine through the cylinder shoulder at a rear position of the striking element,
An air hole is provided in the narrow body between the two sliding parts of the striking element, and a middle cylinder having an air supply hole that can communicate with the air hole is slidably fitted into the fixed cylinder, and the front end of the middle cylinder is slidably displaceable. Since a reverse position holding means that can be engaged with and detached from the inner circumferential surface of the fixed cylinder is provided in the part, it is possible to carry out underground drilling operation, and the underground drilling machine in the forward operating state can be moved by using the air supply hose. You can easily and quickly switch to reverse operation by simply pulling the button. In other words, switching between forward and reverse travel is possible only by pushing and pulling the air supply hose, and the air supply hose is not twisted. Furthermore, since there is no need to operate other components, the switching mechanism is simplified, and even if the switching operation is repeated, the degree of wear and damage is extremely low. As a result, the switching function can be ensured, maintenance and inspection work can be simplified, and the efficiency of the entire through-hole work can be improved.

[Brief explanation of drawings]

Fig. 1 is an overall sectional view of an embodiment of the underground penetrating machine of the present invention, and Fig. 2 is a sectional view of main parts 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 cross-sectional view when the striking element is applying a forward impact;
Figure 4 is a cross-sectional view when the striker is retracted, Figure 5 is a cross-sectional view at the position where the striker starts to retreat inside the underground drilling machine in the reverse operation state, and Figure 6 is a cross-sectional view when the striker is reversed. FIG. 3 is a cross-sectional view when applying an impact of advancement. 2... Piercing machine main body, 3... Striker, 4... Rear variable volume chamber, 5... Front variable volume chamber, 7... Air supply hose, 8A, 8B... Striker sliding part, 9...
... Fixed cylinder body, 10a ... Narrow body part, 12 ... Cylinder shoulder part, 14 ... Air hole, 15 ... Middle cylinder body, 16 ...
Air supply hole, 17... Reverse position holding means.

Claims (1)

[Claims] 1. By supplying compressed 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 through an air supply hose,
In an underground drilling machine in which the striking element is reciprocated within the drilling machine body, two striking element sliders are arranged at different positions in the front and rear, and slide airtightly against the inner wall of the rear variable volume chamber. a fixed cylindrical body fixed within the piercing machine main body via a cylindrical shoulder portion which is integrated at a position rearward of the striking element sliding part and at the rear of the striking element; It has an air supply hole that can communicate with an air hole formed in the narrow body between the sliding parts of the striking element, and the air supply hose is connected to the rear end and is fitted in the fixed cylinder so as to be slidable. a middle cylinder body; the air supply hose is attached to the front end of the middle cylinder body, and is closely fitted to the inner peripheral surface of the fixed cylinder body by pulling the air supply hose, and is integrated with the fixed cylinder body; A reversible underground penetrating machine, comprising: a reversible position holding means that can be detached from the fixed cylindrical body by a pushing action of a supply hose.