JP2006305706A - Inflow regulating mechanism of compressed air in pneumatic tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize securing of a maximum inflow amount of compressed air and a fine regulation of an inflow amount without increasing a pulling load of a trigger lever. <P>SOLUTION: A valve stem 28c is slidably inserted into a pilot valve 22. One end of the valve stem 28c can be pushed from the outside by passing through a bottom part of a valve housing 27 of the pilot valve 22. The valve stem 28c is provided so that a space S between the bottom part of the pilot valve 22 and the valve housing 27 may be successively movable to a first position communicated with a supply passage 18, a second position communicated with the atmosphere, and a third position communicated with the atmosphere and capable of pushing a regulating valve 21 at the other end of the valve stem 28c. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a compressed air inflow adjustment mechanism in a pneumatic tool, which is supplied while adjusting an inflow amount of compressed air when compressed air is supplied from a compressed air supply source to an operating part of a tool body in a pneumatic tool.

  In a conventional pneumatic tool, when supplying compressed air from a compressed air supply source to the working part of the tool body, a trigger valve is provided between the compressed air supply source of the tool body and the working part, and the trigger lever is pulled. Control of the supply and stop of compressed air to the operating unit from a compressed air supply source using a trigger valve.

  Known trigger valve systems include a single valve system such as an air driver and an air wrench, and a pilot valve system such as a nail driver, a screw driver and a turbo driver.

  By the way, in the single pulling type valve, as shown in Patent Document 1, the trigger lever pull amount or the trigger valve valve diameter and the inflow amount of the compressed air are proportional to each other. There is an advantage that it can be supplied to the downstream side while adjusting the amount little by little.

On the other hand, in the pilot valve system, when the trigger lever pull amount reaches a certain position, the sign is switched on and off completely, so a large amount of compressed air is applied at once regardless of the trigger lever pull amount. There is an advantage that can be sent to the operating part.
Japanese Patent No. 2821921

  However, in a single-pull trigger valve, the diameter of the valve must be increased or the operating pressure range must be increased to increase the power of the pneumatic tool in order to ensure the flow rate of compressed air. There is a problem that the pulling load of the trigger valve becomes too large.

  Further, in the pilot valve type trigger valve, the inflow amount of the compressed air cannot be finely adjusted by adjusting the pulling operation of the trigger lever. For this reason, it causes air driver come-out and the like, which is a problem from the viewpoint of usability.

  The present invention solves the above-mentioned problems, incorporates the advantages of single pulling and pilot valve methods, and achieves maximum compressed air inflow and fine adjustment of inflow without increasing the pulling load of the trigger lever An object of the present invention is to provide a compressed air inflow adjustment mechanism in a pneumatic tool that can be used.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a compressed air supply path is formed between the compressed air supply source and the working part of the tool body, and the supply path is opened and closed to open the compressed air supply source. In the pneumatic tool for controlling the operating part by compressed air, a supply port for compressed air is formed in the supply path, and an adjustment valve for opening and closing the intake port is arranged downstream of the intake port. The valve is spring-biased in the closing direction, and on the upstream side, a cylindrical pilot valve is extended on the extension of the axis of the regulating valve, and the end of the pilot valve is in contact with and separated from the opening end of the intake port. The valve stem is slidably arranged to close and open, and the valve stem is slidably inserted into the pilot valve. One end of the valve stem can be pushed from the outside through the bottom of the valve housing of the pilot valve. In addition, the space between the bottom of the pilot valve and the valve housing is communicated with the valve stem at a first position communicating with the supply path, a second position communicating with the atmosphere, and the atmosphere. And the other end of the valve stem is provided so as to be sequentially movable to a third position where the adjustment valve can be pushed.

  According to a second aspect of the present invention, an air passage is formed from the upstream side of the intake port of the supply passage to the back side of the regulating valve, and the air pressure acting on the back side of the regulating valve is biased in the closing direction of the regulating valve. It is characterized by doing.

  According to a third aspect of the present invention, a compressed air supply path is formed between the compressed air supply source and the operating portion of the tool body, and the operating section is opened and closed by compressed air from the compressed air supply source. In the pneumatic tool for controlling the pressure, an intake port for compressed air from the compressed air supply source to the operating portion is formed in the supply path, and a cylindrical pilot valve with a bottom is provided in the intake port, and an end portion of the intake port is the intake port. A valve stem is slidably inserted in the pilot valve so as to close and open the inlet opening in contact with and away from the opening end of the opening, and this valve stem is always inserted into the inlet opening. The valve stem is biased in the closing direction, and one end of the valve stem penetrates the bottom of the valve housing and can be pushed from the outside, and the valve stem is connected to the pilot valve and the valve cylinder. A space between the bottom of the supply passage is movably provided between a first position communicating with the supply passage and a second position communicating with the atmosphere. A choke member for changing the cross-sectional area is provided to be operable.

  According to a fourth aspect of the present invention, a compressed air supply path is formed between the compressed air supply source and the operating portion of the tool body, and the operating section is opened and closed by the compressed air from the compressed air supply source. In the pneumatic tool for controlling the pressure, an intake of compressed air is formed in the supply passage, and an auxiliary intake smaller than the intake is formed downstream of the intake, and the auxiliary intake is formed in the auxiliary intake. A ball valve that opens and closes the intake port is arranged, and the auxiliary intake port is spring-biased in the closing direction. On the upstream side, a cylindrical pilot valve is provided on the extension of the axis of the auxiliary intake port. Is slidably disposed so as to be in contact with and separated from the opening end of the intake port and close and open the intake port, and a valve stem is slidably inserted into the pilot valve. The valve housing can be pushed from the outside through the bottom of the valve housing, and the valve stem has a first position where the space between the bottom of the pilot valve and the valve housing communicates with the supply path, and The ball valve is communicated with the supply path, and is provided so as to be sequentially movable between a second position where the ball valve can be pushed in at the other end of the valve stem and a third position where the ball valve communicates with the atmosphere.

  According to the first aspect of the present invention, fine adjustment is performed in a state where the valve stem is in the second position and the intake port is opened by the pilot valve. In this fine adjustment region, the valve stem pushes the adjustment valve. The inflow increases gradually in proportion to the amount, and finally reaches the third position, the inflow of compressed air becomes maximum. As described above, the inflow amount of the compressed air can be finely adjusted even by the pilot valve method.

  According to the second aspect of the invention, it is possible to achieve the maximum amount of compressed air inflow and fine adjustment of the amount of inflow without increasing the pulling load of the trigger lever. In addition, operability is good and it is hard to get tired.

  According to the third aspect of the invention, since the single pulling method and the pilot valve method are combined, a large amount of compressed air can be introduced at a time and fine adjustment can be performed.

  According to the invention of claim 4, fine adjustment is performed in a state where the valve stem is in the second position and the intake port is opened by the pilot valve. Will flow in. Therefore, since the screw can be rapidly rotated after the tip of the driver is engaged with the groove of the screw head in the fine adjustment region, such work can be performed quickly.

  Moreover, in screw tightening work using a high-power air motor, the output can be reduced in applications where the tightening load is small, such as small screw work or the beginning of screw tightening, and the tightening process can respond to changes in the tightening load. On the other hand, a smooth output fine adjustment function is required. On the other hand, according to the present invention, the trigger load is reduced while the flow rate of compressed air is secured in a high output pneumatic tool, and the inflow adjustment of the supply air by the stroke is performed. Therefore, it is possible to use the air motor at a high output, and it is possible to increase the work efficiency of the operator and to perform bolt and screw fastening work in applications with high tightening load, which was difficult with a low output pneumatic tool. It becomes.

  FIG. 1 is a longitudinal sectional side view showing an impact driver as an example of a pneumatic tool operating with compressed air in a high pressure region. The impact driver 1 includes a tool body 2 in which a handle portion 3 for gripping the impact driver 1 during work is integrally formed toward the rear side, and an impact driver is provided at one end side in the tool body 2. An air motor 4 (actuating portion) that is rotationally driven by compressed air having a pressure in a high pressure region supplied into 1 is disposed, and is connected to the output shaft 5 of the air motor 4 at the other end in the tool body 2. The impact mechanism 6 is accommodated. The output shaft 5 of the air motor 4 is connected to the impact hammer 7 of the impact mechanism 6. When the impact hammer 7 is driven to rotate via the air motor 4, the impact hammer 7 strikes the anvil 8 and impacts the anvil 8. Torque is transmitted. The tip of the anvil 8 is disposed so as to protrude from the end of the tool body 2 to the outside of the tool body 2, and a chuck portion 9 for detachably attaching a driver bit to the tip of the anvil 8 is provided. Is formed.

  The handle portion 3 is formed in a hollow shape. In the hollow portion of the handle portion 3, an air chamber 10 that stores compressed air supplied from a compressed air supply source A, and an air motor 4 after driving the air motor 4. An exhaust chamber 11 for storing exhaust air exhausted from is formed in parallel. An air plug 12 for connecting a socket attached to an end of an air hose connected to the compressed air supply source A to the impact driver 1 is attached to the rear end of the air chamber 10. Compressed air is supplied to the air chamber 10.

  Compressed air exhausted from the air motor 4 by driving the air motor 4 is introduced into the exhaust chamber 11 from the exhaust port 14 formed in the filter case 13 formed at the rear end portion of the handle portion 3 into the atmosphere. Is discharged. An exhaust filter 15 is accommodated inside the filter case 13 in order to reduce the flow rate of compressed air exhausted from the exhaust port 14 to the atmosphere and to blow up dust and wood chips at the work site. The exhaust filter 15 is formed in a cylindrical shape by winding a fine metal mesh in a spiral shape, and is accommodated in the cylindrical filter case 13.

  A supply path for supplying compressed air supplied into the air chamber 10 to the air motor 4 is provided at the base of the handle portion 3 located between the compressed air supply source A and the operating portion (air motor 4) of the tool body 2. 18 is formed, and a compressed air inflow adjusting mechanism 20A for controlling the operation of the air motor 4 by the compressed air by opening and closing a compressed air intake port 19 provided in the supply path 18 is provided.

  As shown in detail in FIGS. 2A, 2B and 2C, the compressed air inflow adjusting mechanism 20A includes an adjusting valve 21 disposed on the downstream side of the intake motor 19 where the air motor 4 is located, and an air chamber. 10 and a pilot valve 22 arranged on the upstream side. Note that both the upstream and downstream opening ends of the intake port 19 are chamfered to form a conical slope.

  The adjusting valve 21 is formed by integrally forming a sliding body 21b on the back side of a truncated cone-shaped valve body 21a. The sliding body 21b is slidable in the valve cylinder 24 with an O-ring 23 attached to the outer periphery. The valve main body 21a is always in contact with the opening end of the intake port 19 and is biased in a direction to close the intake port 19 by a spring 25 provided in the valve housing 24 and the sliding body 21b.

  By the way, an air passage 26 is detoured from the upstream side of the intake port 19 to the back side of the regulating valve 21 so that the compressed air from the air passage 26 acts on the end surface of the sliding body 21b on the back side of the regulating valve 21. It is configured.

  Next, the pilot valve 22 is formed in a cylindrical shape. The pilot valve 22 is slidably disposed in the valve housing 27, and the valve stem 28a is slidably inserted therein. It is provided on the extension on the upstream side of the axis. The valve housing 27 is open to the supply path 18. A through hole 30 is formed at the bottom of the valve housing 27.

  An O-ring 31 is wound around the peripheral edge of the pilot valve 22, and at the top dead center, the O-ring 31 abuts the opening end on the upstream side of the intake port 19 to close the intake port 19 and shut off the air supply. At the bottom dead center, the intake port 19 is opened away from the opening end to supply air. The pilot valve 22 is formed with a small diameter at the top, a larger diameter at the middle and a large diameter at the bottom, with the middle step and the step on the base side. Yes. A communication hole 34 communicating with the inside of the supply path 18 is formed on the side wall near the upper middle side.

  The valve stem 28 a is disposed so as to pass through the pilot valve 22, the upper end of the valve stem 28 a is disposed so that the adjusting valve 21 can be pushed in, and the lower end of the valve stem 28 a is the bottom through hole 30 of the valve housing 27. An operation unit (trigger lever) 35 that can be pushed from the outside is provided. The valve stem 28 a is provided with an upper O-ring 36, an intermediate O-ring 37, and a lower end O-ring 38.

  The valve stem 28a communicates with the atmosphere at a first position where the space S between the bottom of the pilot valve 22 and the valve housing 27 communicates with the supply path 18 (the position shown in FIG. 2A). A second position (position in FIG. 2 (b)) that communicates with the atmosphere and a third position (position in FIG. 2 (c)) that allows the adjustment valve 21 to be pushed in at the other end of the valve stem 28a. It is configured to move to. In the first position, the intermediate O-ring 37 opens the space S in the communication hole 34 of the pilot valve 22, and the lower end O-ring 38 is fitted in the through hole 30 and closed. In the second position, the intermediate O-ring 37 closes the communication hole 34 of the pilot valve 22 and the lower end O-ring 38 opens the through hole 30. Further, in the third position, the intermediate O-ring 37 and the lower end O-ring 38 are the same as in the second position.

  In the above configuration, when the trigger lever 35 is not pulled, that is, when the valve stem 28a is in the first position shown in FIG. 2A, compressed air is supplied to the lower space S of the pilot valve 22. Compressed air acts on both ends of the pilot valve 22, but the pilot valve 22 stands by at the top dead center position where the intake port 19 is blocked by the difference in diameter between the two ends.

  When the trigger lever 35 is lifted by a certain amount, the valve stem 28a moves to the second position in FIG. 5B, and the compression space S below the pilot valve 22 is opened to the atmosphere. Then, the intake 19 is opened. However, in this state, the intake port 19 is closed by the adjustment valve 21.

  When the trigger lever 35 is further pulled, the valve stem 28a moves to the third position in FIG. 5C, and the intake port 19 is open, but the upper end of the trigger lever 35 pushes the adjustment valve 21. The air supply area can be secured by the amount pushed. Therefore, the operator can realize fine adjustment of the supply air flow rate depending on the pulling amount of the trigger lever 35. When the valve stem 28a is moved to the moving end, the intake port 19 is completely released, and the amount of compressed air flowing in is maximized.

  By the way, the regulating valve 21 is urged in the closing direction by the air pressure acting on the back surface of the valve body 21a (the surface surrounding the sliding body 21b) and the load by the spring 25. The compressed air from 26 can be applied to the rear end face of the regulating valve 21 and sealed with an O-ring 23 to generate a valve load. As a result, the necessary spring load can be compensated, so that the adjustment valve 21 can be kept in the air supply cutoff position even if the spring load is small. In addition, since the air supply area at the start of the pilot valve operation is determined by the setting of the area of the end face of the sliding body 21b of the regulating valve 21 and the O-ring diameter and spring load of the regulating valve 21, the initial flow rate can be stabilized. it can.

  Therefore, according to the compressed air inflow adjusting mechanism 20A configured as described above, as shown by the solid line in FIG. 3, fine adjustment is performed when the valve stem 28a is in the second position, and the valve is adjusted in the fine adjustment region. The amount of inflow gradually increases in proportion to the amount by which the stem 28a pushes in the regulating valve 21, and finally the amount of inflow of compressed air becomes maximum when the third position is reached.

  According to the above-described inflow adjustment mechanism, it is possible to secure the maximum inflow amount of compressed air and finely adjust the inflow amount without increasing the pulling load of the trigger lever 35.

  In addition, in screw tightening work using a high-power air motor, the output can be reduced in applications where the tightening load is small, such as small screw work or the beginning of screw tightening, and further, the tightening process can respond to changes in the tightening load. A smooth output fine adjustment function is required. On the other hand, according to the inflow adjustment mechanism 20A, the trigger load is reduced while the flow rate of compressed air is secured in a high-output pneumatic tool, and the air is supplied by a stroke. The air motor can be used with high output, so that it is possible to use the air motor at a high output, and it is possible to increase the work efficiency of the operator and tighten bolts and screws in applications with high tightening loads that were difficult with low output pneumatic tools. Work becomes possible.

  In addition, since it has an adjustment valve 21 with a diameter difference valve and can stabilize the initial flow rate at the start of operation, the rotation failure of the air motor caused by the initial flow rate unmeasurement in the pneumatic tool using the air motor ( It is possible to prevent the compressed air from flowing down.

  In this connection, as shown in FIG. 4, the vertical load of the regulating valve 21 is balanced in the stroke from when the pilot valve 22 is activated until the valve stem 28a starts to push the regulating valve 21. Therefore, when the pilot valve 22 is retracted from the intake port 19, the adjustment valve 21 is set to move slightly backward, so that a constant initial flow rate range (p in the graph of FIG. 3) can be created. Depending on the shape of the regulating valve 21, the responsiveness of the fine flow rate adjustment (gradient q by the one-dot chain line in the graph of FIG. 3) can be set.

  Next, FIGS. 5A and 5B show another embodiment of the inflow adjusting mechanism of compressed air, and it is assumed that it is adopted in the trigger valve of the same impact driver as FIG.

  That is, the inflow adjusting mechanism 20B includes a pilot valve 22 disposed on the upstream side of the intake port 19 and a choke member 40 provided in the supply path 18, as shown in detail in FIG. .

  The basic structure of the pilot valve 22 is the same as that shown in FIGS. 2A, 2B, and 2C, and the operation lever 35 is provided as an operation portion below the valve stem 28a in that the upper end of the pilot valve 22 is closed. Is different, but the basic operation is the same. That is, the valve stem 28 b is slidably inserted into the pilot valve 22, and the valve stem 28 b is always urged by the spring 41 in the closing direction of the intake port 19, and one end of the valve stem 28 b is connected to the valve housing 27. The valve stem 28b can be pushed from the outside through the bottom, and the space S between the pilot valve 22 and the bottom of the valve cylinder communicates with the supply passage 18 at a first position (see FIG. 5 (a)) and a second position (the position shown in FIG. 5 (b)) communicating with the atmosphere.

  Next, the choke member 40 is disposed on the downstream side (or upstream side) of the supply path 18, and the rotation of the disk 42 having the same outer diameter as the inner diameter of the supply path 18 is provided at the center of the supply path 18. The rotary shaft 43 is rotatably fixed to the rotary shaft 43 so that the rotary shaft 43 can be operated from the outside, and the rotary shaft 43 is rotated to change the cross-sectional area of the supply path 18. The rotation operation of the rotation shaft 43 may be performed by an appropriate button or lever (not shown).

  In the above configuration, when the operation lever 35 is not pulled, that is, when the valve stem 28b is in the first position, compressed air is supplied to both ends of the pilot valve 22 as shown in FIG. Reference numeral 22 stands by at a top dead center position where the intake port 19 is blocked by the difference in diameter between both ends. At the same time, the choke member 40 also closes the supply path 18. Next, when the trigger lever is pulled to move the valve stem 28b to the second position in FIG. 5B, the compressed air below the pilot valve 22 is released to the atmosphere. Therefore, the pilot valve 22 moves to the lower bottom dead center position, and the intake port 19 is opened. In this state, the supply path 18 is closed by the choke member 40. Subsequently, when the rotation path 43 is slightly rotated to open the supply path 18 slightly, the upstream compressed air flows into the downstream side.

  Thus, the operator can realize an arbitrary fine adjustment of the air supply flow rate by the rotation amount of the choke member 40.

  Therefore, according to the compressed air inflow adjusting mechanism 20B configured as described above, it is possible to obtain a compressed air inflow change state similar to that shown by the solid line in FIG. 3, which is the same as the compressed air inflow adjusting mechanism 20A. An effect can be obtained.

  In the above embodiment, if the choke member is fully opened in advance, a large amount of compressed air can be introduced at a time.

  6 (a), 6 (b), and 6 (c) show another embodiment of the compressed air inflow adjustment mechanism, which is adopted in the trigger valve of the same impact driver as that in FIG.

  In other words, the inflow adjusting mechanism 20C is arranged on the upstream side of the intake port 19 where the air chamber 10 is located and the auxiliary intake port located on the downstream side of the intake port 19 where the air motor 10 is located, as shown in detail in FIG. And a pilot valve 22. The opening end on the downstream side of the intake port 19 is chamfered to form a conical slope.

  The auxiliary intake port is constituted by a cylindrical body 44, and a ball valve 45 is disposed inside the cylindrical body 44. The ball valve 45 is urged by a spring 46 so as to be pressed against the opening end of the cylindrical body 44 and sealed. In addition, an opening 47 is formed in the side wall of the cylindrical body 44.

  The pilot valve 22 is formed in a cylindrical shape, and is provided on an extension on the upstream side of the axis of the ball valve 45. The pilot valve 22 itself is slidably disposed in the valve housing 27 and has a valve stem 28c slidably inserted therein. The pilot valve 22 is provided on an extension on the upstream side of the axis of the ball valve 45. ing. The valve housing 27 is open to the supply path 18. A through hole 30 is formed at the bottom of the valve housing 27.

  An O-ring 31 is wound around the peripheral edge of the pilot valve 22, and at the top dead center, the O-ring 31 abuts the opening end on the upstream side of the intake port 19 to close the intake port 19 and shut off the air supply. At the bottom dead center, the intake port 19 is opened away from the opening end to supply air. The pilot valve 22 is formed with a small diameter at the top, a larger diameter at the middle and a large diameter at the bottom, with the middle step and the step on the base side. Yes. A communication hole 34 communicating with the inside of the supply path 18 is formed on the side wall near the upper middle side.

  The valve stem 28c is disposed so as to pass through the pilot valve 22. The upper end of the valve stem 28c is disposed so as to be able to push the adjusting valve 21, and the lower end of the valve stem 28c is the bottom through hole 30 of the valve housing 27. An operation portion 35 (trigger lever) that can be pushed from the outside is provided. An upper O-ring 37 and a lower end O-ring 38 are provided on the valve stem 28c.

  The valve stem 28c has a first position where the space S between the bottom of the pilot valve 22 and the valve housing 27 communicates with the supply path 18 (the position shown in FIG. 6A), and the supply path. 18 and a second position where the ball valve 45 can be pushed in at the other end of the valve stem 28c (the position shown in FIG. 5B), and a third position where the ball valve 45 communicates with the atmosphere (the same figure (c)). It is configured to move in a movable manner. In the first position, as shown in FIG. 6A, the upper O-ring 37 opens the space S in the communication hole 34 of the pilot valve 22, and the lower end O-ring 38 is fitted in the through hole 30 and closed. At the second position in FIG. 5B, the upper O-ring 37 and the lower end O-ring 38 are in the same state as the first position. In the third position, the intermediate O-ring 37 closes the communication hole 34 of the pilot valve 22 and the lower end O-ring 38 opens the through hole 30.

  In the above configuration, when the trigger lever 35 is not pulled, that is, when the valve stem 28c is in the first position, the compressed air is supplied to the lower space S of the pilot valve 22 as shown in FIG. Thus, compressed air is supplied to both ends of the pilot valve 22, and the pilot valve 22 stands by at the top dead center position where the intake port 19 is blocked by the difference in diameter between the both ends.

  When the trigger lever 35 is pulled up by a certain amount, the valve stem 28c moves to the second position as shown in FIG. At this time, the pilot valve 22 is maintained in the same state, but there is room for the upper end of the valve stem 28c to push the ball valve 45, so that the auxiliary supply intake 19 is opened by the amount pushed by the ball valve 45 and the compressed air is compressed. Flows into the downstream side, so the air supply area can be secured.

  When the trigger lever is further pulled, the valve stem 28c moves to the third position shown in FIG. 6C, so that the auxiliary intake port 44 remains open and the intake port 19 is further opened. The compressed air is released to the atmosphere. Therefore, the pilot valve 22 moves to the lower bottom dead center position, and the intake port 19 is opened. Therefore, the inflow of compressed air is maximized.

Therefore, according to the compressed air inflow adjusting mechanism having the above-described configuration, as shown by a dotted line in FIG. 3, when the valve stem 28c is in the second position, fine adjustment is performed and the third position is reached. Compressed air will flow in suddenly. Therefore, the same effect as the compressed air inflow adjusting mechanism 20A can be obtained. According to the compressed air inflow adjusting mechanism having the above-described configuration, the valve responsiveness is good, and the mainstream pilot valve is installed with a nailing machine or the like. Therefore, it can be applied in the field of pneumatic tools that do not use an air motor, such as a nailing machine driven by air pressure.

It is a side view of an example of a nailing machine concerning the present invention. (A) (b) (c) is an operation explanatory view of an inflow adjustment mechanism of compressed air. It is a graph which shows the relationship between the stroke of a valve stem by the inflow adjustment mechanism of compressed air, and flow volume. It is operation | movement explanatory drawing of the example which adjusted the balance of the both ends load of an adjustment valve in the said inflow adjustment mechanism. (A) (b) is an operation explanatory view of other compressed air inflow adjustment mechanisms. (A) (b) (c) is an operation explanatory view of another compressed air inflow adjustment mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Nailer 2 Body 18 Supply path 21 Adjustment valve 22 Pilot valve 28a, 28b, 28c Valve stem

Claims (4)

In a pneumatic tool for forming a compressed air supply path between a compressed air supply source and an operating part of the tool body, and opening and closing the supply path to control the operating part by compressed air from the compressed air supply source.
An intake port for compressed air is formed in the supply path, and an adjustment valve that opens and closes the intake port is arranged downstream of the intake port, and the adjustment valve is spring-biased in the closing direction, and on the upstream side. On the extension of the axis of the regulating valve, a cylindrical pilot valve is slidably disposed so that its end abuts and separates from the opening end of the inlet and closes the inlet.
A valve stem is slidably inserted into the pilot valve, and one end of the valve stem can be pushed from the outside through the bottom of the valve housing of the pilot valve, and the valve stem is connected to the bottom of the pilot valve. And a space between the valve housing and a first position communicating with the supply path, a second position communicating with the atmosphere, and communicating with the atmosphere and pushing the adjustment valve at the other end of the valve stem. An inflow adjustment mechanism for compressed air in a pneumatic tool, wherein the mechanism is capable of sequentially moving to a third possible position.   An air passage is formed from the upstream side of the intake port of the supply path to the back side of the regulating valve, and the air pressure acting on the back side of the regulating valve is biased in the closing direction of the regulating valve. Item 10. A compressed air inflow adjustment mechanism in the pneumatic tool according to Item 1. In a pneumatic tool for forming a compressed air supply path between a compressed air supply source and an operating part of the tool body, and opening and closing the supply path to control the operating part by compressed air from the compressed air supply source.
In the supply passage, a compressed air intake port is formed from a compressed air supply source to the operating portion, and a bottomed cylindrical pilot valve is abutted on the intake port and its end abuts the open end of the intake port. Arranged slidably so as to close and open the intake port,
A valve stem is slidably inserted into the pilot valve, and the valve stem is always spring-biased in the closing direction of the intake port. One end of the valve stem can be pushed from the outside through the bottom of the valve housing. In addition, the valve stem is provided so that a space between the pilot valve and the bottom of the valve cylinder is movable between a first position communicating with the supply path and a second position communicating with the atmosphere. ,
An inflow adjustment mechanism for compressed air in a pneumatic tool, wherein a choke member for changing a cross-sectional area of the supply passage is provided upstream or downstream of the pilot valve. In a pneumatic tool for forming a compressed air supply path between a compressed air supply source and an operating part of the tool body, and opening and closing the supply path to control the operating part by compressed air from the compressed air supply source.
A compressed air intake is formed in the supply passage, an auxiliary intake smaller than the intake is formed downstream of the intake, and a ball valve that opens and closes the auxiliary intake is formed in the auxiliary intake. The auxiliary intake port is spring-biased in the closing direction, and on the upstream side, a cylindrical pilot valve is formed on the extension of the axis of the auxiliary intake port, and its end is the open end of the intake port. Slidably arranged so as to close and open the intake port in contact with and away from
A valve stem is slidably inserted into the pilot valve, and one end of the valve stem can be pushed from the outside through the bottom of the valve housing. The valve stem is connected to the bottom of the pilot valve and the valve. A space between the housing communicates with the first position communicating with the supply path, a second position communicating with the supply path and allowing the ball valve to be pushed in at the other end of the valve stem, and the atmosphere. An inflow adjustment mechanism for compressed air in a pneumatic tool, wherein the mechanism is arranged to be sequentially movable to a third position.

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