JPS6195193A - Pneumatically operable reversible impact acting machine - 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 Field of Industrial Application The present invention relates generally to civil engineering and road construction machinery;
More specifically, the present invention relates to a reversible impulse-actuating machine.

The present invention has many advantages when applied to machines for drilling holes in the ground or for driving steel tubes into the ground to be used as casings for underground communications.

Other possible applications of the proposed air-actuated reversible impact machine are driving tubular piles into the ground, compaction of deep-hole mud and driving multiple small nofils directly into the ground. Including.

BACKGROUND OF THE INVENTION Widespread use has recently been found in air-actuated reversible percussion machines, the reversibility of which allows the tube to be retracted for pulling the machine out of the hole and for driving the next tube into the ground. It is necessary to separate the machine from

The ever-increasing field of application of air-operated reversible percussion machines demands improvements in the reliability of these machines. 15m~2
When the extraction of the machine from the hole is complicated, either during horizontal holes with lengths up to 0 m or during vertical holes (such as compacting deep-hole mud or driving concrete piles into the ground). In this case, the mechanism for reversing the impact action must be particularly reliable.

In order to increase its reliability, it is extremely important to keep the device structurally simple6D, which reduces the complexity of the extraction process, makes it cheaper to manufacture, and makes it more susceptible to rear impact effects. Ensures prompt switching.

a substantially hollow cylindrical housing; a hammer housed inside said housing for axially reciprocating motion and impacting the housing with its forward or rearward portion; A device is known (see German Patent No. 1.634417) having stepped tubes connected by threads.

In order to reverse the impact effect of such a device, it is necessary to move said stepped tube to a new position towards the tail of the housing by rotating an air supply hose fixedly attached to said stepped tube. It is.

Reliability in such devices is insufficient because the reversal can be complicated or even impossible when passing through vertical or elongated horizontal holes.

The reversal of the impact action of the device also reduces the efficiency of the device since its operation involves stopping the supply of compressed air and pulling the air hose before disconnecting it from the compressor and rotating the air hose. requires numerous time-consuming actuations that affect

Also, other known impact actuators (West German Patent No. 2340; 75
No. 1) is known, and this machine has a hollow cylindrical housing, a nozzle which is made to reciprocate within the housing and to apply an impact onto the housing with its front or rear part; It comprises a stepped-shaped tube that is securely fixed in a groove in the tail of the housing via fixing means and connected to a hammer.

For the reversal of the impact action of the aforementioned machines, apart from the hoses, the use of flexible steel cables is made. By pulling on the cable, the action of the fixing means is removed and the stepped cheep is moved to a new position. In other words, reversal is made possible by a simple linear movement of the stepped tube instead of a rotational movement.

However, the hose must be routed to bring the stepped tube out of engagement with the grooves and to place the stepped tube in line with the other grooves at its furthest position. As a result, West German Patent No. 2,340.751
The device disclosed in the above-mentioned patent would essentially have the same drawbacks as the previously described devices.

A percussive machine is also known which differs from the above-mentioned machine only in the configuration of the stepped tube (German patent no. 2,105).
．． (See No. 229). In this machine, the stepped tube has an inner step with a plurality of radial through passages similar to an outer step with a plurality of radial through passages, and □
The tube is coaxially fixed to the housing for rotation and axial movement relative to the outer step.

The changeover to reverse impact action is here effected by turning the inner step relative to the outer step by supplying a large quantity of compressed air to the machine. This device offers several advantages over the devices already described in that it does not require rotation of the hose.

However, since multiple intermediate positions may be away from the forward and backward impact effects, a large supply of compressed air may be necessary if the operator is aware of the machine function following every continuous supply of compressed air or if the machine is fully operational. This machine is disadvantageous in that there will be some uncertainty as to whether or not it will. Another disadvantage is that this machine is structurally very complex and therefore difficult to manufacture.

The device most similar to the device proposed in the description that follows is an air-actuated reversing percussion machine as disclosed in German Patent No. 2,722,298. The machine includes a housing, a nozzle which is axially reciprocatable within the housing and has an axial bore in its tail portion open at one end, and a radial passageway. The front working chamber of the hammer is defined by the housing. A stepped cheep housed inside the nozzle fitting has a substantially cylindrical step of larger and smaller diameters, the step extending through radial passages provided within the stepped tube. have

A larger diameter step is placed in said axial bore of the hammer to delimit the rear working chamber, while a smaller diameter step is fixed in the tail part of the nousing by a flange. A spring-loaded sleeve is placed precisely inside the stepped tube. An air supply hose serves as a means of controlling axial movement of the spring-loaded tube. The forward impact action of the machine is initiated when the sleeve assumes its most forward position, and reversal is completed by moving the sleeve to its most rearward position.

Since reversal is accomplished simply by tensioning the hose, and each element of the machine is at any time in a position to perform either a forward or reverse action, no prior art percussion machine has been described to date. This device generally eliminates the disadvantages inherent in conventional structures.

However, even this device is not without some drawbacks. For example, the sliding action and pressure sealing of a sleeve on two of the cylindrical surfaces of the device requires precise manufacturing of the mating surfaces, making the machine more difficult to manufacture. Also, the sliding of the sleeve along its two cylindrical surfaces is unreliable as it can become clogged, especially when dust accumulates on such surfaces.

The machine also has a pressure-sealed interior comprising three isolated sections bounded by a spring-loaded sleeve and stepped tube. This interior must be made hermetically sealed as well for the accuracy of the sliding surfaces.

PROBLEM TO BE SOLVED BY THE INVENTION It is an object of the invention to improve the reliability in reversing mechanical impact effects.

A further object of the invention is to simplify the construction of the machine.

<Means for Solving the Problems> The above and other objects and associated advantages include a housing, a hammer reciprocably disposed within the housing, a cylindrical tube having a stepped shape, and a spring. a biased cylindrical sleeve and means for pressure-sealing the annular recess; said hammer has in its tail portion an axial recess open at one end and has a forward working chamber connected to said housing; the cylindrical tube has a first cylindrical step of larger diameter with a radial through passage and a second cylindrical step of smaller diameter with a radial through passage; a first stage of the tube is disposed within the recess of the hammer to form a rear working chamber, and a second stage of the tube is secured to the tail end of the housing by means of a flange. said cylindrical sleeve is disposed inside said stepped tube for axial movement, and means are provided for controlling said movement; said cylindrical sleeve is mounted within said stepped tube; In an air-actuated reversible percussion machine forming an annular recess with a tube; the first and second stages of the tube are arranged coaxially, and the spring-loaded sleeve disposed inside the step and above the second step, the outer diameter of the sleeve being substantially smaller than the inner diameter of the first step, and an annular passageway connecting the first step and the second step; This is achieved by an air-operated reversible percussion machine, characterized in that it is provided between.

The proposed structure of the machine obviates the sliding of the sleeve on the first cylindrical step of the tube, which prevents it from jamming during movement. Such a structure includes an outer bottom surface of the sleeve and a first part having a large diameter that encompasses the sleeve.
Precision is not required when finishing the surface of the step.

This in turn makes the machine structurally simpler and easier to manufacture. Providing an annular recess between the first stage of the tube and the sleeve prevents the sleeve from jamming during movement of the sleeve, which improves the reliability of the overall machine.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Other objects and advantages thereof will become apparent from the more detailed description of preferred embodiments of the invention, given with reference to the accompanying drawings, in which: FIG.

The air-operated reversible percussion machine comprises a housing 1 and a hammer 2 housed inside the housing 1 for reciprocating movement. At its tail end, the hammer 2 has an axial bore and a through passage 3. Hammer 2 delimits a front working chamber 4 with housing 1 .

The housing 1 also accommodates a substantially cylindrical tube 5 of auxiliary shape, the cylindrical tube 5 having a large diameter cylindrical step 6 and a small diameter cylindrical step 7t, respectively. These steps are arranged coaxially with respect to each other. The tube 5 is securely fixed to the tail part of the housing 1 by means of a flange 8 attached to the step 7.

The step 6 has a radial through passage 9, while the step 7 has a radial through passage 10 and an axial passage 11. A step 6 is arranged inside the axial recess of the hammer 2 to delimit a rear working chamber 12 in the hammer 2 . An annular recess 13 is arranged between the steps 6 and 7 of the tube 5, in which an axially reciprocating cylindrical sleeve 14 is arranged on the step 7. This cylindrical sleeve 14 has an outer diameter that is also substantially smaller than the inner diameter of the step 6 in order to prevent contact between the sleeve 14 and the inner cylindrical surface of the step 6. An annular passage 15 is formed between the sleeve 14 and the step 6, and a spring 16 is mounted on the step 7 of the tube 50.

One end of the spring 16 is supported by the flange 8 and the other end is supported by the end surface of the sleeve 14. Means for pressure-sealing the recess 13 include an elastic sealing element 17 arranged on the end surface of the sleeve 14 and a seat surface 18 in the inner part of the step 6.
provided in the form of

The movement of the sleeve 14 is controlled by a steel cable (FIGS. 1 and 2) or by a tube 20 (FIG. 3) which is connected at one end to an air supply hose 21. The other end of the tube 20 is the passage 1
It is connected to the sleeve 14 by means of a pin 22 identified at 0, allowing axial movement relative to the step 7.

An internal area 23 is provided between the nozzle 2 in the 71 housing 1 and the flange 8, which can communicate with the outside world through a hole 24 made in the flange 8.

The proposed device operates as follows.

(,) In the case of a front impact action of the machine, the normal position of the sleeve 14, i.e. its most extreme position with respect to the head end of the device, is maintained by the spring 16 (FIG. 1). Corresponding to the front impact action of the machine.The initial position of the hammer in the housing 1 is arbitrary.

Cable 19 is not under tension. Prior to operation, the machine is coupled to a compressor (not shown).

By means of the hose 21 the machine is oriented in the desired direction and the special device is placed against the ground to be dug with a slight point in front made by a tool or a simple lever. Being pushed.

Thereafter, the compressor outlet valve directs the compressed air to the hose 21.
It is opened for flow through the axial passage 11 of the tube 5 into the rear working chamber 12 . The compressed air acts to move the hammer 2 until it rests on the end surface of the head portion of the housing 1, opening the radial passages 3 of the hammer 2 as shown in FIG. The compressed air then enters the forward working chamber 4. The working surface area of hammer 2 on the side of chamber 4 is chamber 12
Due to the larger surface area of the chambers 4 and 12, the force exerted on the hammer 2 on the chamber 4 side is greater than the force acting on the chamber 12 side when equal pressures are applied to the two chambers 4.12. Under the action of the resulting force, the hammer 2 moves towards the flange 8 (
(right hand side in Figure 1).

After closing the radial passage 3 by the cylindrical step 6, i.e. even after stopping the supply of compressed air to the chamber 4, the hammer 2 continues to move under the influence of the pressure of the expanded air in the chamber 4. Keep moving. The radial passage 3 of the hammer 2 is the stepped portion 6
coincident with the radial passages 9 of
and through the passage 9 into the recess 13 , after which it enters the inner region 23 and escapes to the outside world through the holes 24 in the flange 8 .

Since chamber 4 is free of pressure, while chamber 12 is continuously exposed to the pressure of compressed air, the hammer 2 is pressed against the housing 1.
(towards the left side as seen in Figure 1) and impacts the inner end surface of the housing.

At the moment of impact, chamber 4 is filled with compressed air in the manner described above, and the cycle described above is thus repeated.

The impact action on the housing 1 causes the machine to penetrate underground (
When digging a hole] or when a steel pipe is coaxially connected to the machine, push the steel pipe into the ground.

(b) In the case of backward action of a machine, such a reversal is usually required to return the machine from a hole previously made by it.

In order to switch the machine into rear shock action, the cable 19 (Figs. 1 and 2) can be connected without stopping the compressed air supply.
1) and by overcoming the compressive force of the spring 16 to move the sleeve 14 to its most rearward position, i.e. from the position shown in FIG. 1 to the position shown in FIG. It is necessary to move it to the correct position.

In this latter position, the resilient sealing element 17 is in full contact with the seat surface 18, whereby the annular recess 13 is pressure-tightly sealed. This means that the radial passage 10 of the cylindrical step 7
, which changes the function of the radial passage 9 of the step 6 and the annular recess 13. More specifically, those parts will be moved away from the system of exhaust channels and into the system of channels supplying compressed air to the working chamber 4.

In the relative arrangement of the elements in the proposed machine shown in FIG. 2, compressed air from the compressor is transferred along the hose 21 and the axial passage 11 to the rear working chamber 12 and An annular recess 1 through a radial passage 10
Moved to 3. The pressure of the compressed air in the annular recess 13 acts on the sleeve 14 to press the sealing element 17 against the seating surface 18 of the step 7, keeping it in that position and thus counteracting the compressive force of the spring 16. I'm winning.

Under the action of the pressure of the compressed air in the chamber 12, the hammer 2 begins its movement towards the end face of the head end of the housing 1. When the radial passage 3 of the hammer 2 is moved into alignment with the radial passage 9 of the step 6, compressed air will flow from the annular recess 13 into the chamber 14. This thing is hammer 2
The hammer 2 is stopped at a certain distance from the flange 8 of the housing 1 by decelerating its movement.

When the chamber 4 is filled with compressed air, the hammer 2 hits the flange 8
It moves towards the flange 8 and gives an impact to the flange 8. At the moment of impact, the compressed air passes from the chamber 4 through the radial passages 3 of the hammer 2 into the internal area 23, as best shown in FIG. escape to.

Following the impact on the flange 8, the hammer 2 moves into the chamber 12 so as to start the movement of the hammer towards the head end of the housing 1 in order to restart the cycle in the manner described above.
Driven by the pressure of the air inside.

Reliable reversibility of the impact action of the proposed machine is ensured when the following conditions are met:

Pl>Pr (1) Pa>P2+Pr (2) where Pl is the initial compression force of the spring 16, P2 is the final compression force of the spring 16, 21, and Pr is the force of the hose 21 during the forward impact action of the machine. (Figure 3).

P & is the force generated by the pressure of the compressed air in the annular recess 13 that acts to press the sleeve 14 towards the seat surface 18 .

The changeover to the reverse operation of the proposed machine can be carried out both before starting and during operation in the forward impulse mode of operation without stopping the supply of compressed air to the machine.

During the rear shock action of the machine, the annular recess 13 is continuously under the pressure of compressed air, which ensures continuous closure of the annular recess 13 by the sleeve 14, so that the sleeve 14 is seated. Ensures a stable position engaging surface 18.

Opening of the annular recess 13, i.e. communication with the atmosphere, is only possible when the supply of compressed air is stopped, which requires moving the sleeve by means of the spring 16 into the position shown in FIG. enable.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a pneumatic reversible percussion actuator according to the invention, showing the relative position of the elements corresponding to the forward percussion action of the machine. FIG. 2 is a longitudinal sectional view similar to FIG. 1 showing the mutual positions of the elements in the reversing action of the machine according to the invention. FIG. 3 is a longitudinal sectional view showing another embodiment of the machine according to the invention. DESCRIPTION OF SYMBOLS 1...Housing, 2...Hammer, 3...Radial passage at the tail end of the hammer, 4...Front working chamber, 5...Stepped-shaped tube, 6...Tube 5 a large diameter cylindrical step, 7 a small diameter cylindrical step of the tube 5, 8 a flange, 9 a radial passage through the cylindrical step 6, 10... A radial passage through the cylindrical step 7, 11... an axial passage through the cylindrical step 7,
12... Rear working chamber, 13... Step part 6 of tube 5
and an annular recess between the stepped portion 7, 14...sleeve, 15...
- Annular passage, 16... Spring, 17... Sealing element, 18... Seat surface, 19... Cable, 20...
Tube, 21... Compressed air supply hose, 22...
pin, 23...inner area, 24...a plurality of holes in the flange 8; 110 Inventor Alexander Demi Soviet Union. Yanovich Fironov 21 0 Inventor Vladaymir Bashi Soviet Union. Lievich Klimashko Chila ■Applicant Proizbodostven Soviet Union. Noe Obiedeinenye “Stromash” Minsk, Ulitsatunyanskaya, 2. Kolpkwartsila 19

Claims (1)

[Claims] 1. A housing (1), a hammer (2) disposed in the housing (1) so as to be reciprocally movable, a cylindrical tube (5) having a stepped shape, and attached by a spring. the hammer (2) comprises a biased cylindrical sleeve (14) and means (17, 18) for pressure-sealing the annular recess (13); said hammer (2) has an axial recess open at one end in its tail portion; a radial through passageway (3) having a radial passageway (3) and delimiting the front working chamber (4) with said housing (1);
said cylindrical tube (5) has a first cylindrical step (6) of large diameter with a radial through passage (9) and a second cylindrical step of small diameter with a radial through passage (10). 2 cylindrical steps (7)
, the first stage (6) of the tube (5) is arranged in the recess of said hammer (2) to form a rear working chamber (12), and the second stage of the tube (5) a step (7) is fixedly attached to the tail end of said housing (1) by means of a flange (8); said cylindrical sleeve (14) is attached to said stepped tube (5);
means are provided for axial movement and for controlling said movement, said cylindrical sleeve (14) forming an annular recess (13) with said tube (5); In the air-operated reversible impact machine, the first stage (6) and the second stage (7) of the tube (5)
are arranged coaxially and said spring-biased sleeve (14) is arranged on the second step (7) inside the first step (6) of the tube (5), said sleeve (14) the outer diameter of which is substantially smaller than the inner diameter of the first step (6) of the tube (5), and the annular passageway (15) is connected to said first step (6).
and the second stage section (7).