JPS5846639B2 - Inverted pneumatic shock device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ground drilling construction machine used for underground wiring work, piling work, etc.

A reversible pneumatic percussion device having the same purpose as the present invention is known, which comprises a cylindrical hollow housing button with a pointed head in the drilling direction and a hammer piston that reciprocates to produce a percussion effect in both the front and back directions. ing.

The hammer forms with the housing a front end working chamber and has a cylindrical space at its rear end in which a stepped pipe is received, which pipe together with the hammer forms the rear working chamber of the device.

The pipe has a rigidly connected sleeve mounted coaxially with the housing for rotation about its axis and for axial movement, the rotational and translational movements of which are restricted by the locking mechanism of the device.

The device further includes lobes that couple to a locking mechanism that restricts rotation of the pipe.

During operation of the device, the lobe is placed in the hole together with a flexible hose for supplying compressed air and always extends outside the hole when facing the ground.

Inverting the device is accomplished by inverting the pipe relative to the housing.

To do this, the device is deactivated by disconnecting the compressed air supply, the stepped pipe is rotated 180° about its axis, torque is transmitted through the flexible hose, and the flexible hose is subsequently tensioned and stepped. The pipe is moved at 1 to stop at the rearmost position, and at this position the flexible hose is locked by turning it 80 degrees.

When the device is pulled out of the ground after drilling, it is switched back to forward motion.

When switching to forward motion, the stepped pipe moves to the frontmost position.

This moving operation is carried out directly without the use of flexible hoses.

Therefore, the force that moves the stepped pipe to the forefront acts on the pipe exposed outside the housing and on the connecting portion with the flexible hose.

Such devices do not allow switching from reverse to forward motion when the device is in the hole.

It is not easy to handle because it has other lobes of the flexible hose.

Further, during the backward movement, the operation becomes complicated because a lobe and two locking mechanisms are used, one for preventing the rotation of the heave and the other for preventing the axial movement.

Another known inverted pneumatic percussion device has a stepped pipe consisting of a sleeve fixed to the housing and a movable sleeve mounted coaxially with respect to the fixed sleeve so as to be movable with the fixed sleeve under the action of compressed air. A compression spring is placed between them to press them in the axial direction.

This device changes the position of the moving sleeve and the direction of impact by changing the air pressure supplied to the device.

Such a device has the disadvantage that the direction of impact may change if the air pressure suddenly changes.

The aim of the invention is to eliminate the above-mentioned drawbacks.

The present invention improves the stepped pin and locking mechanism so that it can be switched from backward to forward motion even when the device is in the hole, and has a simple structure, easy operation button, easy maintenance, and sudden supply air pressure. To provide an inversion type pneumatic shock device which does not perform a reversal operation even if the change occurs.

For this reason, the present invention includes a hollow cylindrical housing having a pointed head in the drilling direction and a hammer piston disposed inside the housing coaxially with the housing, and a mechanism for preventing rotation of the hammer piston around the axis. The hammer piston reciprocates to perform a striking action on the front and rear ends of the housing, the hammer piston forming a front end working chamber with the housing and having a cylindrical space button and at least one opening at the rear end. a radial passageway having an end, the radial passageway periodically communicating the forward end working chamber with the dog button and the cylindrical space, the cylindrical space receiving the main portion of the stepped pipe; The pipe and the hammer piston form a rear end working chamber, a small portion of the pipe is supported at the rear end of the housing and is rotatable about its axis within a range limited by the stopper member; reversible pneumatics supplying compressed air to the partial working chambers to open the radial passages of the hammer piston in constant synchronism to communicate the forward and rear working chambers and to effect opposite movement of the device; In the impact device, the main portion of the pipe has at least one recess at its front end and a protrusion on the rear end at a position opposite the recess, and the length of the recess and the protrusion. are suitably selected and when these are in positions opposite the radial passages of the hammer piston, air is discharged from the front end working chamber so as to perform a percussion action on the rear end of the housing, further decelerating the hammer piston. An inverted pneumatic impact device is provided, characterized in that the air is introduced into the front end actuating chamber to prevent impact action on the front end of the housing.

The reversible pneumatic shock device according to the present invention is capable of switching from a backward motion to a forward motion when the device is in a hole, and has a simple structure and is easy to operate. will not malfunction.

The device shown in FIGS. 1 to 7 has a hollow cylindrical housing 1, the tip of which is pointed in the direction of the piercing, and a hammer piston 2 is housed inside, which reciprocates to impact the front button and the rear.

A cylindrical space 3 is formed at the rear end of this hammer piston, which receives the front end of a vibrator 4 and forms the rear working chamber of the device.

The vibrator 4 is attached coaxially to the housing at its rear end and is rotatable around its axis within a nut 5 firmly fixed to the housing 1.

A flexible hose 6 is connected to the rear end of the vibrator 4 to supply compressed air to the device.

Rotation of the vibrator 4 around the axis is restricted by the protrusion 7 on the vibrator 4 and the stoppers 8, 8a of the nut 5.

Since the pin 9 fixed to the housing 1 is received in the longitudinal groove 10 of the hammer piston 2, the hammer piston 2 does not rotate about its long axis (see FIG. 7).

The inner surface of the housing 1 and the outer surface of the hammer piston 2 form a front working chamber 11 of the device, which periodically communicates with a rear working chamber 3 by a radial passage 12 of the hammer piston 2.

The nut 5 is provided with a longitudinal passage 13 which periodically vents air from the front working chamber 11 of the device to the atmosphere.

A recess 14 is formed at the front end of the main part 4a of the vibrator 4, and a protrusion 15 is formed at the rear end at a position opposite to the recess 14≧Relative arrangement of each member indicating forward movement of the device are shown in FIGS. 1 to 3.

The projection 7 (FIG. 3) of the vibrator 4 engages with the stopper 8 of the nut.

The radial passage 12 moves circumferentially relative to the recess 14 and the projection 15.

The forward movement of the device is performed as follows.

Compressed air is supplied from a source (not shown) via a flexible hose 6 (FIG. 1) and an axial passage 16 of the vibrator 4 to the rear working chamber 3 and from there via a radial passage 12 of the hammer piston 2. front working chamber 1
1.

The hammer piston 2 is moved rearward (
Start moving toward the right side (see Figure 1).

This means that the pressure in the working chambers 3 and 11 is equal and the area of action on the hammer piston 2 is the same in the front working chamber 11.
This is because the force acting on the hammer piston 2 is larger because the side is larger than the rear working chamber 3 side.

When the radial passage 12 of the hammer piston is closed by the vibrator 4 and the introduction of compressed air into the front working chamber 11 is stopped, the hammer piston 2 continues to move backwards due to the expansion effect of the compressed air in the front working chamber 11.

As the hammer piston 2 continues to move rearward, the passage 12 passes through the rear end of the main portion 4a of the vibrator 4 and reaches the position 12 shown by the dotted line in FIG.

Air is discharged from the front working chamber 11 to the atmosphere via the hammer piston 20 radial passage 12 and the nut 5 passage 13.

The hammer piston 2 is stopped by the action of the compressed air in the rear working chamber 3, which is in constant communication with a compressed air supply source, and then moves forward (to the left of the button in FIG. 1) and into the housing 1. (This position of the hammer piston is shown in FIG. 1).

Such operations are repeated successively.

The impact action drives the housing 1 through the ground and compacts it to form a hole with smooth walls.

Such actuation is accomplished by forward movement of the device.

The backward movement of the housing due to the reaction during the reciprocating movement of the hammer piston is prevented by the external and internal rotation of the housing 1 and the friction between the ground.

When forming a vertical blind hole, if the device hits an obstacle such as a large stone, the hole cannot be reoriented and the device must be returned to remove the vibrator driving the device.

In order to return the device, the compressed air supply to the device is stopped, the flexible hose is removed from the compressed air supply source, and the hose is rotated to rotate the vibrator 4, which is firmly fixed to the hose, so that its protrusion 7 (sixth (Fig.) is engaged with the stopper 8a of the nut 5.

In this way, the main portion 4a of the vibrator 4 rotates about its axis and relative to the radial passage 12 of the hammer 2, as shown in FIG.

In this way, the stepped vibrator 4 is positioned with respect to the hammer piston 2 such that the protrusion 15 at the rear end of the main portion 4a and the recess 14 at the front end are on the opposite side of the passage 12.

As a result, compressed air is rapidly supplied to the front working chamber 11 and the pressure piston is decelerated by the compressed air in this chamber without any impact action on the housing.

During the movement of the hammer piston 2 in the direction of the nut 5, the passage 12 of the hammer piston 2 is not opened by the rear end of the protrusion 15, so that the air from the chamber 11 is drawn by the rear end of the main part 4a as in the case of forward movement. It is released later than when it is closed.

Therefore, the stroke of the hammer piston in the direction of the nut 5 increases, and the hammer piston performs a striking action on the nut 5 with its rear end (FIG. 4).

In this way, the device is moved in the opposite direction by a rearward striking action and removed from the hole.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an inverted pneumatic percussion device according to the invention, with the hammer piston in the forward-most position and the pipe illustrating the position of the device in forward motion. FIG. 2 is a developed view of the cylindrical surface of the hammer piston button and pipe having the same diameter as shown in FIG. indicates the relative position of FIG. 3 is a view taken in the direction of arrow B in FIG. 1, and shows the engagement state of the protruding button of the pipe and the nut with the stopper during the forward movement of the device. FIG. 4 is a cross-sectional view of an inverted pneumatic percussion device according to the present invention, showing the rearmost position of the hammer piston during retraction movement of the device. FIG. 5 is a developed view of the hammer piston and pipe having the diameter shown in FIG. 4, showing the recesses and protrusions of the main part of the pipe and the radial passage of the hammer piston in the state shown in FIG. Indicates the relative position. FIG. 6 is a view taken in the direction of arrow C in FIG. 4, and shows the engaged state of the protrusion of the pipe and the stopper of the nut during the backward movement of the device. FIG. 7 is a sectional view taken along the line ■--■ in FIG. 1. 1... House sink, 2... Hammer piston, 4...
- Pipe, 4a... Main part of the pipe, 11... Front end working chamber, 12... Radial passage, 14...
Recess, 15...protrusion.

Claims (1)

[Claims] 1 A hollow cylindrical shape with a pointed head in the drilling direction...Equipped with a hammer piston coaxially arranged inside the hammer piston, and equipped with a mechanism to prevent rotation of the hammer piston around its axis. The hammer piston reciprocates to perform a striking action on the front end and the rear end of the blowfish, and the hammer piston forms a front end working chamber with the housing, and has a cylindrical space and at least two open ends at the rear end. a radial passageway having a radial passageway periodically communicating the front end working chamber with the atmosphere and the cylindrical space, the cylindrical space receiving a main portion of a stepped pipe and connecting the pipe and the hammer; A small portion of the pipe is supported at the rear end of the housing and is rotatable about its axis within the range limited by the stopper member, and the pipe forms a rear end working chamber with the piston. Supply compressed air to the working chamber to
In an inverted pneumatic percussion device, the main part 4a of the pipe 4 is at its front end, opening the radial passage of the pump piston to communicate the front end working chamber with the rear end working chamber and to provide opposite movement of the device. At least one recess 14 and a protrusion 15 on the rear end at a position opposite the recess 14, the recess 14 button and the protrusion 15
When the lengths of the pistons are appropriately selected and they are in positions opposite to the radial passages 12 of the hammer piston 2, air is supplied from the front end working chamber 11 to perform a striking action on the rear end of the Ujifugu 1. An inverted pneumatic shock device characterized in that air is introduced into the front end actuating chamber 11 so that the noma piston 2 is decelerated, thereby preventing the impact action on the front end of the Uji pufferfish. .