JP2009095934A - Automatic pressure reducing air supply valve, and impact wrench and manifold for high pressure pipe with the same valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an impact wrench and manifold for high pressure equipment having a switchable pressure regulating mechanism capable of supplying an air pressure state for enabling a torque control, while fastening a wheel nut with excellent work efficiency in fastening work, and supplying also an air pressure state to obtain power for enabling sure removal of the wheel nut in loosening work. <P>SOLUTION: This automatic pressure reducing air supply valve 20 is provided with an automatic valve 27 for changing pressure of fluid supplied from the outside by energizing force, primary pressure chamber 25 and secondary pressure chamber 29 provided on front and rear sides of the automatic valve 27, a pressure regulating chamber 32 provided on an outer periphery of the automatic valve 27 and a switching valve 21 capable of switching the secondary pressure chamber 29 to a pressure limit state or a pressure no-limit state. During the pressure limit state, the pressure regulating chamber 32 is communicated with the outside via the switching valve 21. During the pressure no-limit state, the pressure regulating chamber 32 is communicated with the secondary pressure chamber 29 via the switching valve 21. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an automatic decompression air supply valve capable of switching high pressure air supplied from an air compressor to a reduced pressure state or a high pressure original pressure state, and an impact wrench and high pressure piping manifold provided with the automatic decompression air supply valve.

  Conventionally, in the field of vehicle maintenance, a dedicated impact wrench corresponding to the size of each vehicle is used for the purpose of tightening or loosening wheel nuts.

  As this impact wrench, there are known a pneumatic type driven by air and an electric type driven by electricity.

  In particular, the pneumatic impact wrench is designed in consideration of machine efficiency, durability, and the like, and is often used at a normal pressure around 0.6 MPa of air supplied from an air compressor.

  Such pneumatic impact wrench (hereinafter simply referred to as impact wrench) is used for tightening the inner nut and outer nut of a wheel with a specified torque in maintenance work for large vehicles such as buses and trucks. The

  On the other hand, it is known that a large load is applied to the inner nut and outer nut used for the wheel of a large vehicle when the vehicle is running or when acceleration / deceleration is performed. Or breakage.

  Therefore, in the tightening operation of the inner nut and the outer nut, it is necessary to manage the tightening torque as strictly as possible, and it is necessary to make the pressure of the air supplied to the impact wrench constant.

  However, the compressed air supplied from a compressor or the like has an unstable pressure, and if used as it is for an impact wrench, there is a risk that the tightening torque will vary.

In order to make the air pressure constant, a method is known in which unstable high-pressure air supplied from an air compressor is decompressed through an automatic pressure reducing valve and the air pressure is kept constant. According to this method, the pressure during use of the impact wrench can be kept constant (see, for example, Patent Documents 1 to 4).
JP 2003-322104 A JP 11-305844 A Japanese Patent Laid-Open No. 10-283036 JP 2004-192462 A

  However, in the operation of removing the inner nut and outer nut described above, a larger force is required as compared with the tightening operation. That is, the wheel nut of a large vehicle that has traveled for a long time is covered with mud and dust, and the frictional force of the screwed part of the bolt and nut is increased, so in order to perform the loosening work to remove the wheel nut, In some cases, nearly twice as much power as the tightening operation is required. Therefore, when the conventional impact wrench is used for both the tightening operation and the removal operation, it is necessary to change the air pressure of the air supplied from the air compressor between the high pressure state and the low pressure state according to the operation. . However, if the air pressure from the air compressor is changed one by one in accordance with the work, the work becomes complicated.For example, when performing the next tightening work after performing the removal work in a high pressure state, Forgetting the operation of reducing the air pressure, there is a risk of using the high pressure (original pressure).

  In order to solve the above-mentioned problems, the air pressure can be supplied so that the torque can be controlled while the wheel nut is tightened efficiently in the tightening operation, and the air can be obtained to securely remove the wheel nut in the loosening operation. It is an object of the present invention to provide an automatic pressure reducing air supply valve having a switchable pressure adjusting mechanism capable of supplying the same pressure state, and an impact wrench equipped with the automatic pressure reducing air supply valve and a manifold for high pressure equipment.

  The invention according to claim 1 is an automatic valve for changing the pressure of fluid supplied from the outside by an urging force, a primary pressure chamber and a secondary pressure chamber provided before and after the automatic valve, and an outer periphery of the automatic valve. In the automatic pressure reducing valve provided with a pressure adjusting chamber provided in the pressure regulating chamber and a switching valve that can be switched to a state in which the pressure of the secondary pressure chamber is limited or not limited, when the pressure is limited, The pressure regulating chamber communicates with the outside via a switching valve, and when the pressure is not limited, the pressure regulating chamber communicates with the secondary pressure chamber via the switching valve.

  The invention according to claim 2 has a recognition mechanism that gives a warning when the pressure is not limited, and communicates the pressure regulating chamber, the secondary pressure chamber, and the recognition mechanism via the switching valve. Features.

  According to a third aspect of the present invention, there is provided an automatic valve for changing the pressure of fluid supplied from the outside by an urging force, a primary pressure chamber and a secondary pressure chamber provided before and after the automatic valve, and an outer periphery of the automatic valve. And a switching valve that can be switched to a state in which the pressure of the secondary pressure chamber is restricted or not restricted, and when the pressure is restricted, the pressure is controlled via the switching valve. When the adjustment chamber communicates with the outside and the pressure is not limited, the automatic decompression supply valve includes an automatic decompression supply valve that communicates the pressure regulation chamber and the secondary pressure chamber via the switching valve. A valve, an air motor driven by compressed air supplied from the automatic decompression air supply valve, a hammer portion driven by the air motor, and an anvil shaft driven to rotate by rotation of the hammer portion. To.

  The invention according to claim 4 has a recognition mechanism that gives a warning when the pressure is not limited, and communicates the secondary pressure chamber, the pressure adjustment chamber, and the recognition mechanism via the switching valve. Thus, the recognition mechanism is movable.

  According to a fifth aspect of the present invention, there is provided an automatic valve for changing the pressure of fluid supplied from the outside by an urging force, a primary pressure chamber and a secondary pressure chamber provided before and after the automatic valve, and an outer periphery of the automatic valve. And a switching valve that can be switched to a state in which the pressure of the secondary pressure chamber is restricted or not restricted, and when the pressure is restricted, the pressure is controlled via the switching valve. When the adjustment chamber communicates with the outside and the pressure is not limited, the pressure reducing chamber and the secondary pressure chamber communicate with each other via the switching valve. A fluid that is supplied from the outside by operating the switching valve, the automatic decompression air valve being connected to the piping so as to communicate with the automatic decompression air valve; Switch valve Characterized by discharging the fluid in the set pressure condition.

  According to the first aspect of the present invention, when the pressure of the high-pressure air supplied from the air compressor is limited, the pressure adjustment chamber is communicated with the outside via the switching valve. Since the air pressure and the external air pressure become equal, the automatic valve operates so that pressure can be reduced, and the air pressure in the secondary pressure chamber is automatically reduced to normal pressure. Further, when the high pressure air supplied from the air compressor is not in a pressure limit state, the pressure adjustment chamber and the secondary pressure chamber are communicated with each other via a switching valve, whereby the air pressure of the secondary pressure chamber and the pressure adjustment chamber are communicated. Therefore, the automatic valve is not actuated by the urging force, and the air pressure equal to that of the primary pressure chamber can be obtained from the secondary pressure chamber.

  According to the second aspect of the present invention, the pressure adjusting chamber, the secondary pressure chamber, and the recognition mechanism are communicated with each other through the switching valve when the pressure is not limited (primary pressure), so that the air pressure in the secondary pressure chamber is obtained. Since the air pressure in the pressure adjusting chamber is equal to the air pressure in the recognition mechanism, the recognition mechanism is activated, and there is an effect of warning the operator that the pressure is not limited (original pressure).

  According to the third aspect of the invention, for example, after loosening the wheel nut in the original pressure state from the air compressor, the automatic switching from the original pressure state to the normal pressure state is performed by operating the switching valve at hand. Therefore, the wheel nut can be safely tightened. By operating the switching valve, the high-pressure air supplied from the outside can be reduced to the normal pressure state or the original pressure state, so that the pressure can be easily adjusted. When the pressure in the secondary pressure chamber is in the original pressure state, the recognition mechanism that shows a warning is movable, so that the operator can recognize that it is in the original pressure state. For example, in the tightening operation of the wheel nut that requires torque management This eliminates accidental use under the original pressure condition, and can be tightened while always performing torque management safely.

  According to the fourth aspect of the present invention, for example, when the tightening operation is performed after the loosening operation, even if the pressure switching of the secondary pressure chamber is forgotten, the recognition mechanism is moved to move the secondary operation. The operator can recognize that the pressure in the pressure chamber is in a high pressure (original pressure) state, and there is an effect that the tightening operation can be performed while always managing the recommended torque without malfunction.

  According to invention of Claim 5, it has at least 1 or more automatic pressure reduction air supply valves, and piping which supplies gas, this automatic pressure reduction air supply valve is connected so that communication with piping is possible, By operating the switching valve, the fluid supplied from the outside is discharged as the fluid in the pressure state set by the switching valve, so that the high-pressure fluid is automatically decompressed, so there is no need to adjust the pressure. By changing the urging force of the automatic valve of the automatic pressure reducing and supplying valve, the pressure discharged from each automatic pressure reducing and supplying valve can be obtained.

  An embodiment of an impact wrench according to the present invention will be described in detail with reference to the drawings. In this embodiment, an automatic pressure reducing air supply valve having a function of switching air pressure supplied from an air compressor is applied to an impact wrench. FIG. 1 is a cross-sectional view in which an automatic pressure reducing air supply valve is disposed on an impact wrench. FIG. 2 is an enlarged view showing a main part of the automatic decompression air supply valve.

  The impact wrench 1 according to the present embodiment supplies an anvil shaft 11 to which a socket 10 for tightening or loosening bolts and nuts can be mounted, a hammer portion 12 for generating an impact torque transmitted to the anvil shaft 11, and compressed air. An air motor unit 13 for generating a rotational driving force, a rotation switching valve 14 for switching the left and right rotation direction by switching the intake and exhaust air to the air motor unit 13, and a control valve 15 for controlling the flow rate of air flow to the air motor unit 13. , A trigger 17 that controls the flow rate of compressed air, a main body casing 18 that houses the components, and compressed air supplied from an external air compressor (not shown) is in a high pressure (hereinafter referred to as source pressure) state (or No pressure restriction) or normal pressure reduced from the original pressure (or pressure restriction) ) In to and an automatic depressurization feed valve 20 to enter the sheet to the main body casing 18 side.

  The automatic decompression air supply valve 20 includes a switching valve 21 that switches the compressed high-pressure air supplied from the air compressor to the original pressure state or the normal pressure state. For example, when the wheel nut tightening of a large truck is performed, the switching is performed. By switching and setting the valve 21 so as to be in the normal pressure state, the wheel nut tightening operation can be realized safely and reliably while maintaining the required torque.

  Further, when the air supplied to the main body casing 18 side is in the original pressure state, the recognition mechanism 22 that indicates a warning is configured to cause the alarm piston 23 to protrude from the automatic pressure reducing air supply valve 20 and generate an alarm sound. have.

  According to this configuration, when performing the loosening operation of the wheel nut of the large truck, the wheel nut is loosened with a torque about twice that of the tightening operation by switching the switching valve 21 so as to be in the original pressure state. Is possible. At this time, the alarm piston 23 indicating the original pressure state jumps out of the automatic pressure reducing air supply valve 20 so that the operator can be informed that the air pressure is in the original pressure state.

  Next, each configuration of the impact wrench 1 will be described.

  The hammer portion 12 includes a cam 12a connected by spline fitting from a rotor 13b, which will be described later, a hammer 12b fixed in the rotational direction of the cam 12a, a hammer cage 12c that rotates at the same speed as the rotor 13b, which will be described later, It is comprised from the anvil shaft 11 integrated with a volt | bolt and a nut.

  The air motor unit 13 includes a rotor 13b, a liner 13c, and a vane 13d that are connected to the rotor shaft 13a in the rotational direction. Each component is housed in the main body casing 18, and is further sandwiched between the rear plate 13e and the front plate 13f. It is what is done.

  The main body casing 18 has a handle shape that also serves as a gripping portion, and has a structure in which the anvil shaft 11, the hammer portion 12, the air motor portion 13, the trigger 17, the control valve 15, the rotation switching valve 14, and the lever 16 are linked and connected. I have. Further, the end of the main body casing 18 is provided with a connection structure that can be mounted while inserting the discharge port of the automatic pressure reducing air supply valve 20.

  An L-shaped lever 16 that switches the rotation direction of the air motor unit 13 is connected to the rotation switching valve 14. For example, when removing the bolts and nuts, the rotation switching valve 14 is operated by switching the lever 16 to the left, and the vane 13d is rotated to the left, so that the loosening operation can be performed. On the contrary, when bolts and nuts are attached, the rotation switching valve 14 is operated by switching the lever 16 to the right, and the vane 13d is rotated to the right, so that the tightening work can be performed.

  The control valve 15 includes a cylindrical valve 15a, and the ventilation flow rate to the air motor unit 13 can be controlled by changing a large and small opening 15b opened on the peripheral surface of the valve 15a.

  Next, the automatic pressure reducing air supply valve 20 will be described in detail.

  The automatic decompression air supply valve 20 according to the present embodiment includes an air supply main body portion 24 capable of withstanding pressure to high pressure air supplied from an air compressor, a primary pressure chamber 25 provided at a proximal end in the air supply main body portion 24, An automatic valve seat portion 26 connected to the primary pressure chamber 25 and an automatic valve 27 capable of moving forward and backward in the air supply main body portion 24 are provided. Further, a secondary pressure chamber 29 provided at the tip of a cylinder 28 to be described later and supplying air to the main body casing 18 side, and a three-way valve shape switching which can be freely rotated so that the air pressure in the secondary pressure chamber 29 can be adjusted. A valve 21 and a structure capable of projecting the alarm piston 23 of the recognition mechanism 22 that warns when the air pressure in the secondary pressure chamber 29 is in the original pressure state are provided. 50 is a passage and 25a is a connecting port for connecting an air hose.

  The automatic valve 27 has a cylinder 28 formed in a substantially cylindrical shape, an automatic valve spring 30 that urges the outer periphery of the cylinder 28 in the direction from the base end to the front end, a structure through which the cylinder 28 can be inserted, and the automatic valve spring 30. And an automatic valve portion 31 that passively passes the urging force.

  In the air supply main body 24, the communication ports 33, 34, 35, 36 that communicate the secondary pressure chamber 29, the alarm piston 23, the outside, and the pressure adjustment chamber 32 provided at the outer peripheral edge of the automatic valve 27 in a cross shape. Is provided. When the switching valve 21 is changed to the normal pressure state or the original pressure state, the communication port 33 of the secondary pressure chamber 29, the communication port 36 of the alarm piston 23, the external communication port 34, and the pressure adjustment chamber of the automatic valve 27. 32 communication ports 35 can be switched so as to communicate with each other.

  The cylinder 28 has a hollow cylindrical shape, and its cross-sectional thickness is gradually reduced from the base end to the tip, and each end face is formed into a doughnut-shaped large diameter 37 and a small diameter 38, and the diameters of the doughnut-shaped areas S2, S1 ( (See FIG. 5). Furthermore, the cylinder outer peripheral surface includes a first step portion 39 that passively biases the automatic valve spring 30 and a second step portion 40 having an oblique cross section, and the first step portion when viewed from the tip end side. It has a donut-shaped diameter area S3 (see FIG. 5) composed of 39 and the second stepped portion 40. The relationship between the donut-shaped areas is such that the equation S2 = S1 + S3 holds.

  The base end and the distal end of the cylinder 28 of the automatic valve 27 are sealed with O-rings 41 and 42, respectively, so that the sealed state is maintained even when the automatic valve 27 moves back and forth.

  The switching valve 21 is rotatably attached to a position in the middle of the air supply main body 24 so as to be able to communicate from the secondary pressure chamber 29 of the automatic valve 27 to the pressure adjustment chamber 32 provided on the peripheral surface of the cylinder 28. . A switching knob 43 (see FIG. 3B) that is exposed to the outside and can be switched with a fingertip is attached to the end face of the switching valve 21.

  The recognition mechanism 22 includes an alarm piston 23 indicating a warning, a cylindrical piston housing 44 containing the alarm piston 23, and an alarm spring 45 for urging the alarm piston 23 so as to be immersed in the piston housing 44. The piston housing 44 is inserted into the opening of the air supply main body 24.

  A switching knob 43 (see FIG. 3B) connected to the switching valve 21 is provided to be rotatable by 90 degrees.

  The alarm piston 23 has a three-stage cylindrical structure that gradually decreases from the proximal end toward the distal end, and the cylinder of the distal end portion 47 is colored, for example, in red indicating a warning.

  When the pressure is not limited (original pressure state), high pressure air vents each communication port from the secondary pressure chamber 29 and flows into the opening of the base end of the piston housing 44, thereby pressurizing the base end of the alarm piston 23. Since the applied pressure is greater than the urging force of the alarm spring 45, the tip portion 47 of the alarm piston 23 protrudes outward.

  Next, the operation state of the automatic pressure reducing air supply valve will be described with reference to FIGS. 3 and 4.

  FIG. 3A is a cross-sectional view showing the switching valve in a state where pressure is limited, and FIG. 3B is a cross-sectional view showing the switching valve in a state where pressure is not limited. FIG. 4A is a cross-sectional view showing the state of each air pressure in the automatic pressure reducing air supply valve in the normal pressure state, and FIG. 4B is a cross-sectional view taken along line YY in FIG. FIG. 4C is a cross-sectional view showing the state of each air pressure in the automatic pressure reducing valve in the original pressure state, and FIG. 4D is a cross-sectional view taken along line YY in FIG. FIG. 5 is a front view showing respective areas at both end faces and outer peripheral edges of the automatic valve.

  First, the normal pressure operation by the automatic pressure reducing air supply valve 20 will be described.

  As shown in FIGS. 3A and 4A, the three-way valve-shaped communication ports 21a, 21b, and 21c of the switching valve 21 include an external communication port 34, a communication port 35 of the pressure adjusting chamber 32, and an alarm piston. The communication port 36 at the 23 base end is communicated, and the external air pressure P2 and the pressure in the pressure adjusting chamber 32 are set to the external air pressure P2. The communication port 33 of the secondary pressure chamber 29 is blocked by the switching valve 21.

  At this time, as shown in FIG. 5, the both ends of the cylinder 28 of the automatic valve 27 have an effective working area difference (S2-S1) due to the difference between the area S1 of the small diameter 38 and the area S2 of the large diameter 37. By generating a pressing force according to the threshold, the interval L is narrowed, the flow rate of the automatic valve seat portion 26 of the throttle portion 48 is controlled, and the air pressure P1 in the air supply passage 49 decreases. The air pressure in the air supply passage 49 and the air pressure in the secondary pressure chamber 29 are equal to the air pressure P 1, and the reduced pressure of the constant pressure P 1 is supplied to the impact wrench 1.

  In the state of the normal pressure P1, the alarm piston 23 is connected to the communication port 36 communicating with the piston housing 44, the external communication port 34, and the communication port 35 of the pressure adjusting chamber 32, so that the alarm piston 23 has the same large size as the outside. Atmospheric pressure P2. At this time, since the urging force of the alarm spring 45 becomes larger than the pressure due to the atmospheric pressure P2, the alarm piston 23 is maintained in the piston housing 44 in an immersed state.

  Next, the original pressure operation by the automatic pressure reducing air supply valve 20 will be described.

  As shown in FIG. 3B and FIG. 4B, the rotation position (see FIG. 3B) of the switching knob 43 connected to the switching valve 21 is from the position of the switching knob 43 at which the pressure is reduced. The position is switched to the position of the switching knob 43 (see FIG. 3D) that is in a high pressure (original pressure) state rotated by 90 °.

  The air pressure in the secondary pressure chamber 29 and the air pressure in the pressure adjustment chamber 32 are switched between the communication port 33 of the secondary pressure chamber 29 and the communication port 35 of the pressure adjustment chamber 32 via the communication port 21a and the communication port 21c of the switching valve 21. By communicating, it becomes equal air pressure P0.

  At this time, as shown in FIG. 5, there is an effective working area difference (S2−) due to the relationship between the small diameter area S1, the large diameter area S2, and the outer diameter area S3. (S1 + S3)) = 0, and the force for driving the automatic valve 27 as described above is not generated. Further, the automatic valve 27 is always in a state where the distance L is maintained by the urging force of the automatic valve spring 30 and the throttle portion 48 is opened.

  Further, the remaining communication port 21 b of the switching valve is in communication with the communication port 36, and further, the communication port 36 and the piston housing 44 are in communication with each other.

  At this time, when air from the secondary pressure chamber 29 flows into the piston housing 44, the air pressure P0 becomes high, and the pressure by the air pressure P0 becomes larger than the urging force of the alarm spring 45, so that the tip of the alarm piston 23 is moved. It will jump out of the piston housing 44. Further, the recognition mechanism 22 is a mechanism that generates an alarm sound indicating a high pressure (original pressure) state simultaneously with the protrusion of the alarm piston 23, and can notify the operator of the state of the high pressure air pressure P0. it can. In such a configuration, when the tightening operation is continuously performed after the loosening operation of the hole nut, the alarm piston 23 protrudes and an alarm sound is generated due to leakage air supply, thereby preventing the operator from forgetting the switching operation of the switching valve 21. Thus, the wheel nut can be accurately tightened with a predetermined torque.

  The automatic valve 27 is pressed against the air supply main body 24 side by the automatic valve spring 30 when the air pressure supplied from the air hose connecting portion is low.

  For example, by supplying air with an air compressor source pressure of 1.4 MPa to 1.5 MPa to the impact wrench, the high pressure region is cut by the automatic decompression air supply valve 20 to obtain a constant pressure of normal pressure 0.6 MPa. Therefore, a constant torque can be obtained when the impact wrench is used. When the wheel nut is loosened, it can be used with the original pressure, improving work efficiency. Moreover, since the switching valve 21 which can be operated at hand is added to the automatic pressure reducing air supply valve 20, it is possible to easily switch to the original pressure state or the normal pressure state at hand, and the operator adjusts the distant pressure reducing valve. The trouble of going to the factory and forgetting to return the regulator can be eliminated.

  In such a configuration, even if the pressure can be easily returned to the normal pressure of 0.6 MPa, the worker may be fatigued due to continuous work, so the concentration may be lost, and even an operation at hand may be forgotten. There is. As a safety device to prevent this, when a high pressure is applied to the secondary pressure chamber 29 of the automatic pressure reducing air supply valve 20, the red alarm piston 23 of the recognition mechanism 22 is ejected, and at the same time, a small amount of air leakage sound is produced. This has the effect of preventing errors. In addition, the air pressure of 0.6 MPa is normally maintained in the tightening operation, and a wheel bolt breakage accident due to excessive tightening can be prevented.

  In addition, the effect which can work safely can be acquired by applying an automatic pressure reduction air supply valve to the oil pulse wrench which pressurizes momentarily via oil intermittently. The tightening of wheel nuts for medium trucks is in the same working environment. Even if the tightening torque management is strictly regulated by combining with medium-sized impact wrench and pulse wrench, this impact wrench with automatic decompression air supply valve can be used. Tightening and loosening operations can be realized.

  Although the case where the automatic pressure reducing air supply valve is applied to the impact wrench has been described as described above, the case where the automatic pressure reducing air supply valve is applied to the manifold for high pressure piping equipment will be described below.

  FIG. 6A is a schematic view showing a manifold for high-pressure piping equipment in which four automatic pressure reducing air supply valves are arranged in parallel, and FIG. 6B is a cross-sectional view taken along line XX in FIG. FIG. 6C is a cross-sectional view showing a switching position of the switching valve in a reduced pressure state. The automatic pressure reducing air supply valve 20 ′ applied to the manifold for high pressure piping equipment is the same except that the recognition mechanism 22 in the automatic pressure reducing air supply valve 20 described above is omitted. Duplicate explanation is omitted.

  The manifold 60 for high-pressure piping equipment according to the present embodiment stores four automatic pressure reducing air supply valves 20 ′ that discharge at different pressures in a box-shaped housing 61, and supplies each of the automatic pressure reducing air supply valves 20 ′. In this structure, the air supply port 25 ′ opened in the middle of the air main body 24 ′ is communicated with the hollow internal pipe 62.

  On the side surface of the casing 61, a throttle part 63 provided with an inflow port through which high-pressure air supplied from the outside flows is disposed. At the base end of the throttle part 63, the longitudinal direction of the internal pipe 62 is provided. The ends are connected so that they can communicate.

  The four automatic pressure reducing air supply valves 20 ′ adjust the elastic force of each automatic valve spring 30 to be different, for example, air pressures 1.0 MPa and 0.8 MPa reduced from the original pressure of air pressure 1.4 MPa. , 0.6 MPa, 0.4 MPa strength can be supplied from the discharge port.

  When the pressure is not limited, each automatic pressure reducing air supply valve 20 ′ has a communication port 33 communicating with the secondary pressure chamber 29 and a communication port 36 communicating with the pressure adjustment chamber 32, as shown in FIG. By communicating with both the communication ports 21b and 21c of the switching valve 21, the air pressure in the pressure adjusting chamber 32 and the air pressure in the secondary pressure chamber 29 are in the same pressure state, so that the automatic valve 27 does not operate and the pressure is high. The original pressure state can be obtained.

  When the pressure is limited, each automatic pressure reducing air supply valve 20 ′ has a switching valve 21, as shown in FIG. 6 (c), having a communication port 34 communicating with the outside and a communication port 36 communicating with the pressure adjustment chamber 32. By communicating with both the communication ports 21a and 21c, the air pressure in the pressure adjusting chamber 32 becomes the same as the external air pressure, so that the automatic valve 27 is activated and the air pressure in the secondary pressure chamber 29 is automatically increased. Pressure) state to any pressure state.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments, and various modifications can be made within the scope of the gist of the present invention described in the claims.・ Change is possible.

It is sectional drawing which shows the structure of the impact wrench which concerns on this embodiment. It is sectional drawing which shows the principal part of the impact wrench shown in FIG. (A) It is sectional drawing which shows the switching valve in the state which pressure-limits. (B) It is sectional drawing which shows the switching valve in the state which does not carry out pressure restriction. (A) It is sectional drawing which shows the state of each air pressure in the automatic pressure reduction air supply valve in a normal pressure state. (B) It is sectional drawing in the YY line of Fig.4 (a). (C) It is sectional drawing which shows the state of each air pressure in the automatic pressure reduction air supply valve in a source pressure state. (D) It is sectional drawing in the YY line of FIG.4 (c). It is a front view which shows each area in the both end surfaces and outer periphery of an automatic valve | bulb. (A) It is the schematic which shows the manifold for high pressure piping equipment which concerns on this embodiment. (B) It is sectional drawing in the XX line of Fig.6 (a). (C) It is sectional drawing which shows the switching position of the switching valve in a pressure reduction state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Impact wrench 20 Automatic pressure reduction air supply valve 21 Switching valve 22 Recognition mechanism 25 Primary pressure chamber 27 Automatic valve 29 Secondary pressure chamber 32 Pressure adjustment chamber

Claims (5)

An automatic valve for changing the pressure of fluid supplied from the outside by an urging force, a primary pressure chamber and a secondary pressure chamber provided before and after the automatic valve, a pressure adjusting chamber provided on an outer periphery of the automatic valve, In the automatic pressure reducing air supply valve provided with a switching valve that can be switched to a state in which the pressure in the secondary pressure chamber is restricted or not restricted,
When the pressure is limited, the pressure adjusting chamber communicates with the outside via the switching valve,
When the pressure is not limited, the pressure adjusting chamber and the secondary pressure chamber are communicated with each other via the switching valve. 2. The automatic pressure reducing device according to claim 1, further comprising: a recognition mechanism that indicates a warning when the pressure is not limited, and the pressure adjustment chamber, the secondary pressure chamber, and the recognition mechanism are communicated with each other via the switching valve. Air supply valve. An automatic valve for changing the pressure of fluid supplied from the outside by an urging force, a primary pressure chamber and a secondary pressure chamber provided before and after the automatic valve, a pressure adjusting chamber provided on an outer periphery of the automatic valve, A switching valve that can be switched to a state in which the pressure in the secondary pressure chamber is restricted or a state in which the pressure is not restricted, and
When the pressure is limited, the pressure adjusting chamber communicates with the outside via the switching valve,
When the pressure is not limited, an automatic pressure reducing valve that communicates the pressure adjusting chamber and the secondary pressure chamber via the switching valve is provided.
The automatic pressure reducing air supply valve, an air motor driven by compressed air supplied from the automatic pressure reducing air supply valve, a hammer portion driven by the air motor, and an anvil shaft rotated by rotation of the hammer portion An impact wrench characterized by And a recognition mechanism for indicating a warning when the pressure is not limited, and the recognition mechanism is movable by communicating the secondary pressure chamber, the pressure adjustment chamber, and the recognition mechanism via the switching valve. The impact wrench according to claim 3. An automatic valve for changing the pressure of fluid supplied from the outside by an urging force, a primary pressure chamber and a secondary pressure chamber provided before and after the automatic valve, a pressure adjusting chamber provided on an outer periphery of the automatic valve, A switching valve that can be switched to a state in which the pressure in the secondary pressure chamber is restricted or a state in which the pressure is not restricted, and
When the pressure is limited, the pressure adjusting chamber communicates with the outside via the switching valve,
When the pressure is not limited, an automatic pressure reducing valve that communicates the pressure adjusting chamber and the secondary pressure chamber via the switching valve is provided.
Having at least one automatic decompression air supply valve and a pipe for supplying gas;
The automatic pressure reducing air supply valve is connected so as to be able to communicate with the pipe,
A manifold for high pressure piping, wherein a fluid supplied from outside is discharged as a fluid in a pressure state set by a switching valve by operating the switching valve.

Images