JP2008221348A - Pneumatic tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a safe pneumatic tool which well prevents a finishing material from being fouled, and has excellent working efficiency and operability. <P>SOLUTION: A pipeline 16 leading to an air duster 12 is branched and connected to the intermediate part of an air pipeline 13 connecting a compressed air supply source and an air chamber 4. A selector valve 15 movable between a first position where a valve element 18 in a valve housing 17 opens an upstream side pipeline 13a leading to a compressed air supply source to a downstream side pipeline 13b leading to the air chamber 4 to cut off a branch pipeline 16 for the air duster 12, and a second position where it opens to a branch pipeline 16 by cutting off the downstream side pipeline 13b, is installed in the branch part. An operating pipeline 28 branched from the air chamber 4 is connected to a selector valve 15 through an opening/closing valve 30 by an operating button 32. When the operating pipeline 28 is closed by the operating button 32, the valve element 18 is moved to the first position, and opened by the operating button 32, it is moved to the second position. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pneumatic tool with an air duster provided with an air duster for blowing compressed air to a pneumatic tool such as a nailing machine, a screw driving machine, and a screwing machine using compressed air as a driving source.

  For example, when wood nails are driven into a base material of a floor material in flooring construction, fine wood chips or the like may fall on the base material. If this is left as it is and a finishing material is stacked on the base material and a nail is driven in, the finishing material will rise due to wood chips on the base material, and the work must be repeated. In order to prevent such inconvenience, the surface of the base material is cleaned with an air duster, and then the finishing material is set and the driving work is performed. However, since the air duster was provided separately from the nail driver, it was very troublesome because the nailer and the air duster had to be frequently changed during the operation of driving a large number of finishing materials.

In order to solve such inconvenience, there is known a nailing machine provided with an air duster itself (see Patent Documents 1, 2, and 3). According to this, it is not necessary to change the nail driver and the air duster one by one, which is convenient in that respect.
Japanese Patent No. 3385875 JP 2004-1135 A JP 2004-1136 A

However, the nailer with the air duster described above has the following drawbacks.
(1) Since the compressed air for the air duster is taken out from the same part as the air chamber (pressure accumulating chamber), the oil injected into the nailing machine body is discharged to the air duster along with the dirt of the striking mechanism, and finished. Since the oil that has been discharged and adhered to the material adheres, there arises a problem that the target material is soiled.
(2) Since compressed air comes directly from the air chamber, the launching direction of the fastener is different from the blowing direction of the compressed air. Therefore, when using an air duster, an operator must change the direction of the pneumatic tool, and workability is not good.
(3) When performing a cornering operation for driving a nail into the lower inner corner, an operator often changes the pneumatic tool for convenience and operates the trigger lever with a little finger. May unintentionally press the operation button on the air duster. In this case, since the compressed air for the air duster is taken out from the same part as the air chamber, the air pressure in the air chamber is lowered or the dust near the work part rises and the workability is not good.
(4) The position where the operator grips the grip of the pneumatic tool and puts his finger on the trigger lever is slightly different from the position where his finger hits the operation button. Therefore, when using an air duster, the gripper must be gripped before working. The operability is not good.
(5) Since the pneumatic tool is connected to the compressed air supply source via the air hose, when the pneumatic tool placed on the floor is in a remote position, the pneumatic tool is pulled by pulling the air hose. However, the pneumatic tool is likely to be caught on a pillar or the like, and the air duster may be operated by pressing an operation button at that time.

  The present invention solves the above-mentioned problems in the prior art, there is almost no risk of driving a pneumatic tool, especially when an air duster is used, and the finish material can be satisfactorily prevented from being contaminated, and workability and operability are also improved. It is an object of the present invention to provide an excellent pneumatic tool.

  In order to solve the above-mentioned problem, an invention according to claim 1 is provided with an air duster that blows out compressed air to a tool body, and an air tube that connects a compressed air supply source and an air chamber for storing compressed air provided inside the tool body. An air duster conduit that leads to an air duster that blows out compressed air is branched in the middle of the passage. The valve body in the valve housing compresses the upstream conduit that leads to the compressed air supply source in the branch. A first position that opens to a downstream pipe line that leads to an air chamber that stores air and that blocks the air ducter branch line, and a second position that blocks the downstream pipe line and opens to the branch pipe line. A switching valve movable to the position is connected, and an operating pipe branched from the air chamber is connected to the switching valve via an open / close valve by an operating button, and the operating pipe is connected by the operating button. When the valve is closed, the valve body moves to the first position, and when the operation pipe is opened by the operation button, the valve body moves to the second position. .

  According to a second aspect of the present invention, in the first aspect, the blowing nozzle of the air duster is disposed in the vicinity of the launching portion, and the blowing direction of the air from the air duster is substantially the same as the ejection direction of the fastener by the tool body. It is characterized by that.

  The invention according to claim 3 is characterized in that, in claim 1 or 2, the operation button is arranged on a side surface of the tool main body within a range in which a thumb or an index finger of an operator who holds the tool main body reaches. .

  According to the first aspect of the present invention, the valve body of the switching valve opens the upstream pipe line leading to the compressed air supply source to the downstream pipe line leading to the air chamber storing the compressed air, and the branch pipe for the air duster. Since it is provided so as to be movable to a first position where it is blocked with respect to the road and a second position where it is blocked with respect to the downstream pipe line and opened to the branch pipe line, when using an air duster, The downstream pipe line leading to it is automatically shut off. Therefore, there is almost no danger when using the air duster.

  In addition, since the air duster is branched from the pipeline before being supplied to the air chamber, the lubricating oil lubricated to the nailing machine body does not turn to the air duster along with the dirt of the striking mechanism including the air chamber. Even if compressed air is blown onto the material, oil and dirt do not adhere to the surface.

  According to the invention of claim 2, the air duster blowing nozzle is disposed in the vicinity of the launching portion, and the air blowing direction from the air duster is substantially the same as the fastener ejecting direction by the tool body. Since the operator does not need to change the direction of the pneumatic tool when used, workability is good.

  According to the invention of claim 3, since the operation button is arranged on the side surface of the tool body, the operator can change the pneumatic tool for the sake of convenience and operate the trigger lever with the little finger when making the bottom corner. However, since the operator's hand does not press the operation button of the air duster, dust does not rise unexpectedly, and the workability is good.

  In addition, since the operation button is located within the reach of the operator's thumb or index finger holding the tool body, there is no need to re-grip the grip when using the air duster with the finger on the operation button. Is good.

  In addition, when pulling the air hose during work and pulling the pneumatic tool, even if the pneumatic tool gets caught on a pillar etc., the possibility that the operation button will be pushed is very small, so there is almost no accidental activation of the air duster. .

  Hereinafter, an embodiment of a pneumatic tool according to the present invention will be described with a nailing machine based on the drawings. The pneumatic tool is not limited to a nailing machine. What is necessary is just to drive using compressed air, for example, a screwdriver, a screwing machine, etc. may be sufficient.

  The nailing machine body 1 of the nailing machine is provided with an impact mechanism. The striking mechanism drives the striking piston 3 slidably accommodated in the striking cylinder 2 using the compressed air stored in the air chamber 4, and drives the striking piston 3 from the magazine 6 by a driver 5 coupled integrally with the striking piston 3. The nail (headless nail, finish nail, etc.) supplied into the nose portion 9 is struck and driven. The supply of compressed air into the air chamber 4 includes a trigger valve 8 activated by the operation of the trigger lever 7 and It is configured to be performed based on the opening operation of the interlocked main valve 10. In order for the trigger lever 7 to operate the trigger valve 8 effectively, it is necessary that the tip 19 (see FIG. 7) of the contact arm is pressed against the workpiece.

  Next, the nailer is provided with an air duster 12 (see FIG. 5). That is, the compressed air is configured to be taken into the air chamber 4 from the opening 11 at the end of the grip portion 14 through an air pipe 13 such as an air hose connected to an air supply source (not shown) such as an air compressor. In the middle of the air pipe 13, a pipe line 16 that leads to the air duster 12 via a switching valve 15 is branched.

  A switching valve 15 is disposed at the branch portion. The switching valve 15 is provided with a valve body 18 in the valve housing 17 so as to be slidable in the vertical direction. The valve body 18 is an air that stores compressed air in an upstream pipe line 13a that communicates with the compressed air supply source. 1st position (position shown in FIG. 1) which opens to the downstream pipe line 13b leading to the chamber 4 and cuts off from the branch pipe line 16 for the air duster 12, and cuts off from the downstream pipe line 13b, It is movable to a second position (position shown in FIG. 3) that opens to the branch pipe 16 and is normally biased to be in the first position by a spring 20.

  The air duster branch pipe 16 extends from the end cap 21 of the grip part 14 through the rear part of the magazine 6 and the front part of the magazine 6 along the nose part 9, and as shown in FIG. 12 a is arranged slightly above the rear end of the tip of the nose portion 9.

  Incidentally, as shown in detail in FIG. 2, the uppermost end of the valve body 18 of the switching valve 15 has a first O-ring 22 with the smallest diameter, a second O-ring 23 with the largest diameter at the middle upper part, and a third O with the middle diameter at the lower part. A fourth O-ring 25 is provided around the ring 24 and the lower end. A central hole 26 is formed at the center of the valve body 18, and the central hole 26 is closed between the third O ring 24 and the fourth O ring 25, and is opened upstream through a through hole 27 on the side wall. Yes.

  In addition, an operating line 28 is connected between the first O-ring 22 and the second O-ring 23 of the valve housing 17 of the switching valve 15. The working line 28 branches off from the air chamber 4, and as shown in FIG. 6A, an opening / closing valve 30 is disposed in the middle thereof. The opening / closing valve 30 is provided with a valve stem 31 so as to be movable between a position for closing the working conduit 28 (position shown in FIG. 6A) and an opening position (position shown in FIG. 6B). It is constructed so that it can be integrally connected and opened and closed from the outside, and normally, as shown in FIG. 6A, the upstream side where the O-ring 34 on the distal end side of the valve stem 31 communicates with the air chamber 4 by the spring 33. It is urged to be in a closed position where the downstream line 28b communicating with the line 28a and the switching valve 15 is blocked. Then, by pressing the operation button 32 and moving the valve stem 31 as shown in FIG. 5B, the space between the two O-rings 34 and 35 is connected to the upstream side conduit 28 a that leads to the air chamber 4 and the switching valve 15. It connects so that the downstream pipe line 28b which leads may be connected. When the valve stem 31 is in the closed position, the compressed air in the downstream working line 28b leaks from the discharge line 36 to the outside.

  As shown in FIG. 7, the operation button 32 is disposed on the side surface of the tool body 1 at the upper position of the trigger lock 37. In this position, when the right-handed operator grasps the grip portion 14, the operation button 32 can be pushed in with the thumb as it is without changing the grip. When the operator is left-handed, the operator can push the operation button 32 with the index finger as it is without changing the grip when gripping the grip portion 14. Thus, it is preferable to arrange the operation button 32 within a range where the operator's thumb or forefinger who holds the tool body 1 can reach.

  Next, the operation mode of the nailing machine having the above configuration will be described. When the air duster 12 is not used, the open / close valve 30 is held in the closed position as shown in FIG. Thereby, since the compressed air is not supplied to the working pipe 28, the compressed air from the compressed air supply source has a large upward force due to the difference in diameter between the third O-ring 24 and the first O-ring 22. 1 and the first position of FIG. The valve body 18 opens the upstream side pipe line 13a leading to the compressed air supply source to the downstream side pipe line 13b leading to the air chamber 4 storing the compressed air, and shuts off the branch pipe line 16 for the air duster 12. Therefore, the compressed air from the compressed air supply source is continuously supplied to the air chamber 4, the striking mechanism is activated by the pulling operation of the trigger lever 7 and the pressing operation of the contact arm 19, and the nail is driven out from the nose portion 9. .

  On the other hand, when the air duster 12 is used, the operation button 32 is pushed with the thumb (or index finger) while holding the grip portion 14, and the open / close valve 30 is moved to the open position as shown in FIG. 6B. Then, the compressed air from the air chamber 4 is sent between the first O-ring 22 and the second O-ring 23 of the valve housing 17 of the switching valve 15 through the working conduit 28. As a result, air pressure acts on the first O-ring 22 and the second O-ring 23, but the diameter of the second O-ring 23 is larger, and the compressed air from the compressed air supply source passes through the through hole 27 on the side wall of the valve body 18. Since it acts on the upper end of the valve body 18 via the center hole 26, the valve body 18 moves to the 2nd position below as shown in FIG. Thereby, the upstream side pipe line 13a leading to the compressed air supply source through the fourth O-ring 25 is blocked from the downstream side pipe line 13b, and the space between the second O-ring 23 and the third O-ring 24 is branched. , The compressed air is supplied to the branch pipe 16 and blown out from the blowout nozzle 12a at the tip. The blowing nozzle 12a is disposed slightly above the rear end of the nose portion 9 and the air blowing direction from the air duster 12 is substantially the same as the nail launching direction, so the operator changes the direction of the pneumatic tool. There is no need.

  When the use of the air duster 12 is stopped, the finger may be released from the operation button 32. Since the valve stem 31 is moved to the position shown in FIG. 6A by the spring 33 which closes the working line 28, the downstream side of the working line 28 leaks from the discharge line 36 to the outside. For this reason, since the air pressure acting downward on the second O-ring 23 is reduced, the valve body 18 rises again and returns to the position of FIG.

  Next, the operator keeps pressing the operation button 32 of the air duster 12, that is, when the switching valve 15 is at the second position in FIG. 3, compressed air is supplied from the air plug 38 provided at the rear end of the grip portion 14. The air hose leading to the supply source may be accidentally pulled out. In this case, as shown by the valve body 18a in FIG. 4A, compressed air is supplied to the sealed space between the first O-ring 22 and the second O-ring 23, whereas the upstream side of the switching valve 15 is provided. Since the compressed air in the side pipe line 13a is released to the atmosphere, the air pressure of the compressed air acting on the upper end of the valve body 18a is also reduced to the atmospheric pressure, and the air pressure in the branch pipe line 16 to the air duster 12 is also large. Atmospheric pressure. Therefore, the air pressure of the compressed air includes an upward pressure P1 acting on the lower portion of the first O-ring 22, a downward pressure P2 acting on the upper portion of the second O-ring 23, and an upward pressure P3 acting on the lower portion of the fourth O-ring 25. Since P2−P1 <P3 + the load of the spring 20 is established, the valve body 18 rises like the valve body 18b in FIG. 5B and returns to the first position. As a result, the compressed air in the air chamber 4 and the compressed air in the working conduit 28 are both released from the air plug 38 to the atmosphere, and eventually no compressed air remains in the nailing machine body. Even if 7 is pulled, the driving of the nail is not activated by the residual pressure, which is safe.

  As described above, the switching valve 15 opens the upstream pipeline 13a that leads to the compressed air supply source to the downstream pipeline 13b that leads to the air chamber 4 that stores the compressed air, and the branch valve 16 for the air duster 12 opens. In contrast, when the air duster is used, the air chamber 4 is provided so as to be movable to the first position where it is blocked and the second position where it is blocked from the downstream pipe line 13b and opens to the branch pipe line 16. The downstream pipe line 13b leading to is automatically shut off. Therefore, there is almost no danger when using the air duster.

  In addition, since the blowing nozzle 12a of the air duster 12 is disposed in the vicinity of the launching portion, and the air blowing direction from the air duster 12 is substantially the same as the launching direction of the fastener, the operator can use the air duster 12 when using the air duster 12. Workability is good because there is no need to change the orientation of the pneumatic tool.

  Furthermore, since the operation button 32 is arranged on the side surface of the tool body 1, the operator can change the pneumatic tool for convenience when operating the lower corner and operate the trigger lever 7 with a little finger. Since the user's hand does not press the operation button 32 of the air duster 12, dust does not rise up unexpectedly, and the workability is good.

  In addition, since the operation button 32 is disposed within a range where the thumb or index finger of the operator who holds the tool body 1 can reach, there is no need to re-grip the grip when using the air duster 12 with the finger placed on the operation button 32. Therefore, operability is good.

  Further, when pulling the air hose and pulling the pneumatic tool, even if the pneumatic tool is caught on a pillar or the like, the possibility that the operation button 32 is pushed is very small, so that the air duster 12 is hardly operated by mistake. .

  In addition, the structure of the on-off valve is not limited to the above-mentioned thing. For example, in the open / close valve 30 shown in FIG. 8A, the upstream working line in which the O-ring 42 on the tip end side of the valve stem 31 is communicated with the air chamber 4 by a spring 40 as shown in FIG. It is urged to be in a closed position that shuts off the downstream working conduit 28b that leads to 28a and the switching valve 15. Then, by pressing the operation button 32 and moving the valve stem 31 as shown in FIG. 5B, the space S between the two O-rings 42 and 43 is switched to the upstream working line 28 leading to the air chamber 4. A downstream working line 28 that leads to the valve 15 is connected. When the valve stem 31 is in the closed position, the downstream working conduit 28b can leak to the outside from the vicinity of the operation button 32 through the central through hole 39 of the valve stem 31, as indicated by an arrow. It has become.

  Further, the open / close valve 30 shown in FIGS. 9 (a) and 9 (b) is normally provided with one O-ring 45, 46 between the front end side and the middle of the valve stem 31 by a spring 44, as shown in FIG. 9 (a). Is urged to be in a closed position where the upstream working line 28 a communicating with the air chamber 4 and the downstream working line 28 b communicating with the switching valve 15 are blocked. Then, as shown in FIG. 5B, the operation of the upstream side in which the space between the two O-rings 45, 46 on the tip side and the base side leads to the air chamber 4 by pushing the operation button 32 and moving the valve stem 31. The pipe 28 a is connected to the downstream working pipe 28 b communicating with the switching valve 15. When the valve stem 31 is in the closed position, as shown by the arrow, the downstream working conduit 28b is communicated with the atmosphere via the gap around the valve stem 31 and the inner wall of the valve housing. Leak from the vicinity of the button 32 to the outside.

  Next, FIG. 10 shows another embodiment of the switching valve, in which the same reference numerals as in the previous figure indicate the same members. The switching valve 15 has a bottomed cylindrical valve sleeve 47 fixed to one side in the valve housing 17 and a relief valve 50 having the same inner diameter as the valve sleeve 47 slidably received on the other side. 47 and a relief valve 50, a bottomed cylindrical valve body 48 is slidably accommodated in the valve housing 17. The valve housing 17 has an upstream pipe 13 a that leads to a compressed air supply source and a downstream that leads to an air chamber 4. The side pipe line 13b, the branch pipe line 16 that leads to the air duster 12, the exhaust pipe line 49, and the working pipe line 28 that leads to the on-off valve 30 are formed as openings.

  The relief valve 50 has a lower position (the position shown in FIGS. 10 and 11) where the upper bottom 51 engages with the end of the valve housing 17, and an upper position where the opposite open end 52 engages with the valve sleeve 47. Slide between positions (position shown in FIG. 12). Further, the valve body 18 is engaged at the first position (the position shown in FIG. 10) where the valve sleeve 47 is engaged with the upper bottom portion 51, and the second position where the open end 52 is engaged with the bottom portion 54 of the valve sleeve 47 (FIG. 11 and the position shown in FIG. The valve sleeve 47 and the valve body 48 are supplementarily urged toward the lower bottom 51 by a spring 55. As will be described later, the relief valve 50 operates only at the time of preventing the explosion.

  An opening 56 is formed at the center of the lower bottom 51 of the relief valve 50, and three O-rings 57, 58, and 59 having the same diameter, large diameter, medium diameter, and small diameter, are provided on the outer peripheral surface. A through hole 60 is formed between the two O-rings 57 and 58 having a large diameter and a medium diameter. Further, three O-rings 61 having the same diameter are provided around the outer peripheral surface of the valve body 48 at substantially equal intervals.

  An open / close valve 30 (here, shown in FIGS. 9A and 9B) is provided between the air chamber 4 and the switching valve 15.

  In the above configuration, when the air duster 12 is not used, the relief valve 50 and the valve body 48 are held at a lower position (the valve body 48 is the first position) by the spring 55 as shown in FIG. In the first position, the upstream line 13a that leads to the compressed air supply source opens to the downstream line 13b that leads to the air chamber 4 that stores the compressed air, and is blocked from the branch line 16 for the air duster 12. . Therefore, the compressed air from the compressed air supply source is continuously supplied to the air chamber 4, the striking mechanism is activated by the pulling operation of the trigger lever 7 and the pressing operation of the contact arm, and the nail is driven out from the nose portion 9. .

  On the other hand, when the air duster 12 is used, as shown in FIG. 11, when the operation button 32 is pushed and the opening / closing valve 30 is moved to the open position, the compressed air from the air chamber 4 passes through the working line 28. The air pressure is supplied from the opening 62 at the end of the switching valve 15 through the opening 56 in the lower bottom 51 of the relief valve 50 to the space S between the relief valve 50 and the lower bottoms 51 and 63 of the valve body 48. As a result, the valve body 48 moves to the second position on the opposite side against the spring 55. As a result, the intermediate O-ring 61 blocks the upstream pipe line 13a leading to the compressed air supply source from the downstream pipe line 13b and opens to the branch pipe line 16, so that the compressed air is supplied to the branch pipe line 16. The air is blown out from the blowing nozzle 12a at the tip.

  The pressure of the compressed air acts on the outer surface of the lower bottom portion 51 of the relief valve 50, but at the same time, the compressed air acts on the open end 52, and the pressure receiving area on the lower bottom portion 51 side is that of the open end 52 side. The relief valve 50 does not move.

  When the use of the air duster 12 is stopped, the finger may be released from the operation button 32. Compressed air in the working line 28 on the downstream side of the opening / closing valve 30 is leaked to the outside through a gap on the operation button side. Therefore, since the air pressure acting on the valve body 18 is reduced, the valve body 48 rises again and returns to the first position in FIG.

  Next, when the operator presses the operation button 32 of the air duster 12, that is, when the air hose leading to the compressed air supply source is accidentally pulled out from the air plug 38 when the switching valve 15 is in the second position. As shown in FIG. 11, since the compressed air in the pipe line 13a on the upstream side of the switching valve 15 and the branch pipe line 16 to the air duster 12 are released to the atmosphere, the relief valve 50 and the valve body 48 are opened to the open side. The acting air pressure is reduced to atmospheric pressure. On the other hand, since the compressed air remains in the downstream side pipe 13b and the working line 28, the compressed air in the working line 28 flows under the valve housing 17 and the relief valve 50 as shown in FIG. The relief valve 50 is supplied to the space S between the bottoms 51, and the relief valve 50 moves upward by this air pressure. For this reason, the small-diameter O-ring 59 of the relief valve 50 is detached from the valve housing 17, and the compressed air in the working line 28 and the air chamber 4 are exhausted from the exhaust line 49. Since the compressed air in the air chamber 4 and the compressed air in the working pipe 28 are both released from the air plug 38 to the atmosphere, the compressed air does not remain in the nailing machine body. Even if it is pulled, the driving of the nail is not activated by the residual pressure, which is safe.

  Next, FIG. 13 shows another embodiment of the switching valve 15, and in this figure, the same reference numerals as those in the previous figure indicate the same members. In the switching valve 15, a cylindrical valve body 64 and a relief piston 65 are slidably disposed in series in the valve housing 17, and a part of the relief piston 65 is slidably accommodated in the valve body 64. In the valve housing 17, an upstream line 13 a that communicates with the compressed air supply source, a downstream line 13 b that communicates with the air chamber 4, a branch line 16 that communicates with the air duster 12, and an air vent hole 66. Each of the working lines 28 leading to the opening / closing valve 30 is opened.

  The valve body 64 is composed of a large diameter portion 64a and a small diameter portion 64b, and the relief piston 65 is also composed of a large diameter portion 65a and a small diameter portion 65b. Further, the large diameter portion 65a of the relief piston 65 and the small diameter portion 64b of the valve body 64 are formed so as to be able to engage with each other, and a spring 71 is disposed therebetween.

  Further, the valve body 64 opens the upstream side pipe line 13a leading to the compressed air supply source to the downstream side pipe line 13b leading to the air chamber 4 storing the compressed air, and cuts off the branch pipe line 16 for the air duster 12. Between the first position (position shown in FIG. 13) and the second position (position shown in FIG. 15) that blocks the upstream pipe 13a from the downstream pipe 13b and opens to the branch pipe 16. It is slidably arranged.

  Note that the opening / closing valve 30 described above is provided between the air chamber 4 and the switching valve 15.

  In the above configuration, when the air duster 12 is not used, the relief piston 65 and the valve body 64 are held in positions opposite to each other by the spring 71 (the valve body 64 is the first position). In the first position, the compressed air from the compressed air supply source is continuously supplied to the air chamber 4, the striking mechanism is activated by the pulling operation of the trigger lever 7 and the pressing operation of the contact arm, and the nail is removed from the nose portion 9. Be launched.

  On the other hand, when the air duster 12 is used, the operation button 32 is pushed in to open and close the opening / closing valve 30. As a result, the compressed air is supplied to the downstream working pipe 28 and further fed into the switching valve 15, so that the relief piston 65 moves toward the small diameter portion 65b against the spring 71 as shown in FIG. To do. For this reason, the O-ring 67 of the small-diameter portion 65b moves further than the position of FIG. 14 and disengages from the small-diameter portion 65b of the valve body 64, so that the compressed air flows between the large-diameter portion 64a of the valve body 64 and The valve body 64 is moved to the second position shown in FIG. As a result, the O-ring 69 of the small-diameter portion 64b blocks the upstream side pipe line 13a leading to the compressed air supply source from the downstream side pipe line 13b and opens to the branch pipe line 16, so that the compressed air flows into the branch pipe line 16. Supplied and blown out from the blowing nozzle 12a at the tip.

  The valve body 64 hits the large diameter portion 65a of the relief piston 65 in the middle of moving to the second position, pushes the relief piston 65 back to the original position, and is stable when the valve body 64 moves to the second position. To do.

  When the use of the air duster 12 is stopped, by releasing the finger from the operation button 32, the air in the working line 28 on the downstream side of the opening / closing valve 30 is leaked to the outside. For this reason, the air pressure acting on the valve body 64 is reduced, rises again, and returns to the first position in FIG.

  Next, while the operator has pressed the operation button 32 of the air duster 12, that is, when the valve body 64 is in the second position in FIG. 15, the air hose that leads to the compressed air supply source from the air plug 38 is accidentally pulled out. In this case, as shown in FIG. 16, both the compressed air in the upstream pipe line 13a of the valve body 64 and the compressed air in the space S are released to the atmosphere. On the other hand, since the compressed air remains in the downstream working pipe 28, the relief piston 65 moves to the first position of the valve body 64 while being engaged with the valve body 64. Thereby, the branch line 16 to the air duster 12 is also released to the atmosphere. Since the O-ring 70 at the end of the relief piston 65 is disengaged from the sliding portion of the valve housing 17, the compressed air in the switching valve 15 and the air chamber 4 is released from the air plug to the atmosphere. Therefore, since compressed air does not remain in the nail driver main body, even if the trigger lever 7 is accidentally pulled, the nail driving is not activated by the residual pressure, which is safe.

Longitudinal sectional view of a nailing machine according to the present invention Enlarged sectional view of the initial state of the switching valve Enlarged sectional view showing the operating state of the switching valve (A) (b) is sectional drawing which shows the state before and behind at the time of malfunction of a switching valve Side view of nailer showing air duster position (A) (b) is sectional drawing which shows the operation | movement aspect of an on-off valve Perspective view of nailing machine showing the position of the operation button of the open / close valve a) (b) is sectional drawing which shows the operation | movement aspect of another on-off valve (A) (b) is sectional drawing which shows the other operation | movement aspect of an on-off valve. Sectional drawing which shows other embodiment of a switching valve Sectional drawing which shows the operation | movement aspect of the said embodiment Sectional drawing which shows the operating state at the time of malfunction of the said embodiment Sectional drawing which shows other embodiment of switching valve Sectional drawing which shows the mode in operation | movement of the said embodiment. Sectional drawing which shows the operation | movement aspect of the said embodiment Sectional drawing which shows the operation state at the time of abnormal operation of the said embodiment

Explanation of symbols

a Air duster 13a Upstream side pipe line 13b Downstream side pipe line 12 Air duster 15 Switching valve 16 Branch pipe line 18, 48, 64 Valve body 28 Operating pipe line 32 Operation button

Claims (3)

An air duster that blows compressed air to the tool body, and an air duster that leads to an air duster that blows compressed air in the middle of the air line that connects the compressed air supply source and the compressed air storage air chamber provided inside the tool body. Branching pipes,
In the branch portion, the valve body in the valve housing opens an upstream pipe line that leads to the compressed air supply source to a downstream pipe line that leads to an air chamber that stores compressed air. A switching valve that is movable to a first position that is blocked with respect to the second position that is blocked with respect to the downstream pipe line and opens to the branch pipe line;
Connect the working line branched from the air chamber to the switching valve via an open / close valve with an operation button,
The valve body moves to the first position when the operation conduit is closed by the operation button, and the valve body moves to the second position when the operation conduit is opened by the operation button. A pneumatic tool characterized by the above.   The blow nozzle of the air duster is disposed in the vicinity of the launching portion, and the air blowing direction from the air duster is made substantially the same as the direction of fastener ejection by the tool body. Pneumatic tools.   3. The pneumatic tool according to claim 1, wherein the operation button is arranged on a side surface of the tool main body within a range where a thumb or an index finger of an operator who holds the tool main body can reach.

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