JPS6059060B2 - High speed impact tool air control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-speed impact tool used in metal rolling processing, and more particularly to an air control device for a high-speed impact tool.

The high-speed impact tool uses high pressure to fill the closed space formed by the top wall of the high-pressure gas working chamber and the cup-shaped end on the upper end of the rod of the ram member (hammer) when the ram member is in its uppermost position. The ram member is configured to continuously generate an impact stroke by alternately communicating the pressure within the gas working chamber and atmospheric pressure.

Generally, an air control device for a high-speed impact tool is required to have its operating element move at high speed with a short stroke and consume little operating air.

This is because the actuation of a high-speed impact tool is carried out by supplying a high pressure gas (usually air or an inert gas such as nitrogen) to the working chamber at a leakage pressure of 150 to 20, and the impact action time exceeds a few hundredths of a second. This is because if the operation of the air control device cannot follow the operation of the high-speed impact tool, it will directly affect the operating efficiency of the high-speed impact tool. Accordingly, it is common practice to use pneumatic control systems with slip valves controlled by solenoid or spring-loaded distribution valves in high speed impact tools. A pneumatic control device for high-speed impact tools is known, for example, as disclosed in Soviet Inventor's Certificate No. 463,504.

This air control device includes a passage communicating with the atmosphere, a passage communicating with the high pressure gas working chamber of the high speed impact tool, and the upper end of the rod of the ram member and the top wall of the high pressure gas working chamber when the ram member assumes the uppermost position. The pressure gastight body has three passages communicating with a closed space formed by the pressure gastight body, and the pressure gastight body is provided with a pair of slide valves that are reciprocated by a slide valve displacement device. The slide valve is operative to close a passage communicating between the pressure gas tight body and the atmosphere when the slide valve is in a first end position, and the other slide valve is operable to close a passage communicating between the pressure gas tight body and the atmosphere when the slide valve is in a first end position. When in position, it is configured to operate to control a passageway communicating between the pressure gas seal and the high pressure gas working chamber of the high speed impact tool. Furthermore, the closing of the passages by the slide valves is effected by the gas pressure in the high-pressure gas working chamber acting on the slide valves, and the opening of the passages is effected by a slide valve displacement device of the actuating cylinder type which cooperates with the respective slide valve. However, in this conventional air control device, since the passage by the slide valve is closed by the gas pressure in the high-pressure gas operating chamber, a considerably large impact force acts between the slide valve and the valve seat, causing damage to both. This will cause premature wear.

As a result, high-pressure gas leaks between the slide valve and the valve seat, which prevents accurate air control, leading to irregular reciprocation of the ram member of the high-speed impact tool, which can lead to failure of the high-speed impact tool. I will invite you. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a pneumatic control device for a high-speed impact tool that is configured to prevent excessive impact forces from acting between the slide valve and the valve seat, and thus has a long service life and reliability. It is possible to provide a highly flexible air control device.

This object of the invention is achieved by an air control device constructed as follows.

That is, a pressure gas-tight body 1, a pair of slide valves 5 and 6 provided so as to be able to reciprocate within the pressure gas-tight body 1, and the 1
A pneumatic control device for a high-speed impact tool, comprising a slide valve displacement device for reciprocating a pair of slide valves 5 and 6 between a first end position and a second end position, is a passage 2 communicating with the high pressure gas working chamber 16 of the high speed impact tool.
and a closed cavity formed by the top wall of the high pressure gas working chamber 16 and the cup-shaped end 23 provided at the upper end of the rod 18 of the ram member 19 when the ram member 19 of the high speed impact tool occupies the uppermost position. 21, and a passage 4 that communicates with the atmosphere.
in the end position, the slide valve 5 opens said passage 2;
A slide valve 6 closes said passage 4 and said slide valves 5, 6 close said second passage 4.
in the end position, the slide valve 5 closes said passage 2;
In the pneumatic control mechanism of a high-speed impact tool, the slide valve 6 is configured to open the passage 4, the slide valve displacement device has a piston 9 reciprocating within the working cylinder 7, and a piston 9 on both sides of the working cylinder 7. a pair of arms 10 arranged;
11, one end of each of the pair of arms 10, 11 is pivotally connected to the pressure-tight body 1, and each other end is provided with an elastic element 13.
The piston 9 includes piston rods 8, 8 protruding from both sides thereof, each of which connects to the pair of arms 10, 11.
The pair of slide valves 5 and 6 are arranged so as to be in contact with each of the piston rods 8 and 8 of the piston 9.
The pair of arms 10 and 11 are placed on a straight line parallel to the piston 9 and are pivoted by being pressed by the piston rods 8 and 8 during the reciprocating movement of the piston 9. This is achieved by a high-speed impact tool pneumatic control device characterized in that it is reciprocated between. That is, according to the air control device of the present invention, the pressure of high-pressure gas from a high-speed impact tool is not used as a force for closing the slide valve, but the slide valve is closed using the spring force of the elastic element. There is.

Therefore, excessive impact force does not act between the slide valve and the valve seat, which prevents premature wear of the slide valve and valve seat, increasing the reliability of the air control device and extending the life of high-speed impact tools. It can be made longer. DESCRIPTION OF THE PREFERRED EMBODIMENTS The air control device for a high-speed impact tool according to the present invention will be described below with reference to the accompanying drawings.

The high speed impact tool pneumatic control device of the present invention has three passages 2
, 3, 4, and a pair of slide valves 5, 6.
and a slide valve displacement device for displacing the slide valves 5 and 6.

The sliding valve displacement device also includes an actuation cylinder 7 disposed above the pressure-tight body 1, a piston 9 sliding inside the actuation cylinder 7, and two arms 10 disposed on both sides of the actuation cylinder 7. , 11. The first end (the lower end in the drawing) of each arm is pivotally connected to the pressure gas seal 1 by a pin 12, and the second end (the upper end in the drawing) is supported by an elastic member such as a spring. They are interconnected by elements 13. The spring force of the elastic element 13 is sufficient to close the slide valves 5,6. Instead of the elastic element 13, a hydraulic cylinder (not shown) may be used to interconnect the second ends of the two arms 10, 11. Each of the arms 10, 11 includes a piston rod 8, which protrudes from both ends of the piston 9.
8 is starting to work together. The slide valves 5, 6 can be reciprocated within the pressure-tight body 1 and are arranged in line so as to be substantially parallel to the piston rods 8, 8 of the piston 9. The free end of the slide valve 5 (the end protruding from the gas-tight body 1) cooperates with an arm 10, and likewise the free end of the slide valve 6 cooperates with an arm 11. In order to cause the piston 9 to reciprocate, a pair of compressed air inlets and outlets (not shown) are provided in the left and right cylinder chambers 7a and 7b of the piston 9, respectively. Therefore, when compressed air is supplied from the compressed air inlet of the cylinder chamber 7a on the left side of the piston 9, the piston 9 moves to the right and the arm 11 pivots around the pin 12 in a clockwise direction. This results in
Arm 10 is also pulled by elastic element 13 and pin 12
Pivot clockwise around. This pivoting movement of the arms 10, 11 closes the slide valve 5 and, conversely, opens the slide valve 6. That is, according to the invention, the slide valve 5 is closed by the spring force of the elastic element 13.
When the arm 11 pivots in the clockwise direction, the arm 11 and the limit switch 14 come into contact and an electric circuit (shown) controlling the supply of compressed air is activated, which in turn causes the cylinder chamber 7b on the right side of the piston 9 to be activated. compressed air is supplied to the
When compressed air is supplied to the right cylinder chamber 7b, the piston 9 moves to the left, so that the arm 10 pivots around the pin 12 in a counterclockwise direction, and at the same time the arm 11 also moves against the elastic element 13. It is pulled and pivoted counterclockwise. This opens the slide valve 5 and closes the other slide valve 6. That is, according to the invention, the sliding valve 6 also has the elastic element 1
It is designed to be closed by the spring force of 3. In this specification, the position in which the arms 10, 11 pivot most counterclockwise (i.e., the position where the slide valve 5 opens and the slide valve 6 closes) is referred to as the 1st end position, and vice versa. The most pivoted position in the rotational direction (i.e. the slide valve 5 is closed,
The position in which the slide valve 6 is opened will be referred to as the second terminal position. Note that switching between supplying compressed air to the cylinder chamber 7a on the left side of the piston 9 or to the cylinder chamber 7b on the right side is performed using the ram member 1 of the high-speed impact tool as described later.
It is performed in correspondence with the movement of 9. The high speed impact tool is constructed as shown in the drawings, as is generally known, and includes a ram member 19 reciprocably housed within a housing 17. A high pressure gas working chamber 16 is formed in the upper part of the housing 17, and a high pressure gas (usually air or an inert gas such as nitrogen is used) is continuously supplied to the high pressure gas working chamber 16. A supply port (not shown) is provided. The upper end of the rod 18 of the ram member 19 forms a cup-shaped end 23 such that when the ram member 19 occupies the uppermost position as shown, the cup-shaped end 23
The peripheral edge of the high-pressure gas working chamber 16 is in close contact with an elastic sealing element 20 provided on the top wall of the high-pressure gas working chamber 16, and a closed space 21 is formed between the cup-shaped end 23 and the top wall of the high-pressure gas working chamber 16. This closed space 21 becomes a closed space 21 completely isolated from the high pressure gas working chamber 16 when the ram member 19 is in the uppermost position as shown. With this configuration, when the ram member 19 is in the uppermost position shown, the gas pressure inside the high-pressure gas working chamber 16 acts on the outside of the small knob-shaped end 23, as will be described later. When the closed space 21 communicates with the atmosphere through the conduit 22 and the passages 3 and 4 of the pressure-tight body 1, the ram member 19 is held in the uppermost position by the pressure difference acting on the inside and outside of the cup-shaped end 23. I can do it. The air control device for the high-speed impact tool of the present invention and the high-speed impact tool are communicated as follows.

That is, the passage 2 of the pressure gas seal 1 of the air control device communicates via the conduit 15 with the high pressure gas working chamber 16 of the high-speed impact tool, and the passage 3 of the pressure gas seal 1 communicates via the conduit 22 with the high pressure gas working chamber 16 of the high-speed impact tool.
The top wall of the high pressure gas working chamber 16 and the rod 18 of the ram member 19
It communicates with a closed space 21 formed by a cup-shaped end 23 provided at the upper end of the holder. Note that the passage 4 of the airtight body 1 communicates with the atmosphere. The conduits 15 and 22 have a pressure of 15 to 20 MPa.
Use one that can withstand pressure of (megapascal. luni 153 to 204 k9/CTl). The high speed impact tool pneumatic control system of the present invention operates as follows.

Initially, the ram member 19 of the high speed impact tool is held in the uppermost position as shown.

This is typically accomplished by a ram return device (not shown) located below the high speed impact tool. In this state, high-pressure gas is continuously supplied into the high-pressure gas working chamber 16, but compressed air is also supplied to the cylinder chamber 7a on the left side of the working cylinder 7 of the air control device, and the arms 10, 11 occupies the most pivoted position in the clockwise direction (second end position), so that the slide valve 5 is closed and, conversely, the slide valve 6 is in the open position. Therefore, the pressure inside the high-pressure gas working chamber 16 is maintained at a high pressure, but the pressure inside the closed space 21 is maintained at a high pressure through the conduit 22,
Since it communicates with the atmosphere through the passages 3 and 4, even if the ram return device is released, the ram member 19 still occupies the uppermost position as shown due to the pressure difference between the inside and outside of the cup-shaped end 23. be able to. Therefore, when the slide valve 5 is closed and the slide valve 6 is opened, the ram return device is released. As mentioned above, limit switch 14 is actuated by arm 11 when arm 11 reaches the second end position.

When the limit switch 14 is actuated, the actuating cylinder 7
The electric circuit that controls the piston 9 is activated, and compressed air is now supplied to the cylinder chamber 7b on the right side of the piston 9. This causes the arms 10, 11 to assume the most pivoted position in the counterclockwise direction (first end position), so that the slide valve 5 is open and, conversely, the slide valve 6 is closed. Therefore, the high pressure gas in the high pressure gas working chamber 16 is transferred to the conduit 15 and the passage 2.
, 3 and the conduit 22 to the closed space 21, and the pressure in the high pressure gas working chamber 16 and the pressure in the closed space 21 become equal. The ram member 19 is therefore struck down and the first impact stroke is made. After the first impact stroke,
The ram member 19 is returned to the uppermost position shown by the ram return device, and the same impact stroke is then repeated according to the cycle described above.

As described above, the air control device of the present invention has a sliding valve 5.
, 6 are closed by the spring force of the elastic element 13,
Compared to conventional air control devices that are closed by the pressure of high-pressure gas, wear on the valve and valve seat when the valve is closed can be significantly reduced, extending the life of the air control device.

Claims (1)

[Claims] 1 A pressure gas-tight body 1, a pair of slide valves 5, 6 provided so as to be able to reciprocate within the pressure gas-tight body 1, and a pair of slide valves 5, 6 placed between a first end position and a second end position. The air control device for a high-speed impact tool includes a slide valve displacement device for reciprocating displacement between a terminal position and a terminal position of the high-speed impact tool. and a closed space 21 formed by the top wall of the high-pressure gas working chamber 16 and the cup upper end 23 provided at the upper end of the rod 18 of the ram member 19 when the ram member 19 of the high-speed impact tool occupies the uppermost position. A passage 3 that communicates with the atmosphere and a passage 4 that communicates with the atmosphere are formed, the passage 2 communicates with the passage 3 when the slide valve 5 is opened, and the passage 3 communicates with the passage 3 when the slide valve 6 is opened. communicates with the passage 4 when the slide valve 5
, 6 are in the first end position, the slide valve 5 opens the passage 2, the slide valve 6 closes the passage 4, and the slide valve 5 opens the passage 4.
, 6 in a second end position, the slide valve 5 closes the passage 2 and the slide valve 6 opens the passage 4, in a pneumatic control mechanism of a high speed impact tool, the slide valve displacement The device has a piston 9 that reciprocates within a working cylinder 7, and a pair of arms 10, 11 disposed on both sides of the working cylinder 7, one end of each of the pair of arms 10, 11 being connected to the The piston 9 is pivotally connected to the pressure-tight body 1 and is interconnected at each other end by an elastic element 13, said piston 9 having piston rods 8, 8 projecting from both sides thereof, said piston rods 8, 8 are arranged so as to abut each of the pair of arms 10, 11, and the pair of slide valves 5, 6 are arranged on a straight line parallel to the piston rods 8, 8 of the piston 9. reciprocating displacement between the first end position and the second end position by the pair of arms 10, 11 which are arranged and pivoted by being pressed by the piston rods 8, 8 during the reciprocating movement of the piston 9; A pneumatic control device for a high-speed impact tool characterized by: