JP2004255566A - Driving machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving machine for preventing an O ring from falling off the groove of a plunger or a valve bush without changing the sliding resistance between the valve pistons of the plunger or valve bushes. <P>SOLUTION: The driving machine is driven by compression air, and a trigger valve section has the plunger 7 traveling by trigger operation, and a surface sliding with the plunger. The driving machine comprises: the valve piston 9 traveling in a direction opposite to the travel of the plunger; and valve bushes 10, 11 that have a surface sliding with the plunger and valve piston and supports the plunger and the valve piston movably. The driving machine slides with the valve piston, and irregularities are provided on the other sliding surface. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a driving machine for driving a fastener such as a nail.

  An example of the driving machine will be described with reference to FIGS.

  Compressed air from a compressor (not shown) is accumulated in a pressure accumulating chamber 2 in the driving machine body 1 via an air hose (not shown). A cylindrical cylinder 3 is provided in the driving machine main body 1, a piston 4a is provided in the cylinder 3 so as to be slidable up and down, a driver blade 4b is integrally formed with the piston 4a, and a tip 4c is formed. The nail 5 is driven.

  The trigger valve section 6 includes a plunger 7 that is moved up and down by a trigger 39, and a valve piston 9 that moves in a direction opposite to the plunger 7 in response to the movement of the plunger 7 to directly supply and discharge compressed air in the sleeve valve chamber 8. , Valve bushings 10 and 11 movably supporting the plunger 7 and the valve piston 9, and a spring 12 provided between the plunger 7 and the valve piston 9. An O-ring 15 is provided at an upper portion of the plunger 7 to interrupt an air passage 14 that communicates the valve piston lower chamber 13 with the atmosphere.

  O-rings 21 and 23 which intermittently connect an air passage 20 for communicating the atmosphere with the sleeve valve chamber 8 and an air passage 22 for communicating the air passage 20 and the pressure accumulating chamber 2 are fitted to the valve piston 9. An O-ring 24 that always closes the chamber 13 and the air passage 22 is fitted. When the valve piston 9 is located at the top dead center, the pressure accumulating chamber 2 and the sleeve valve chamber 8 communicate with each other, the space between the sleeve valve chamber 8 and the atmosphere is closed, and when the valve piston 9 is located at the bottom dead center, The atmosphere communicates with the sleeve valve chamber 8 and the space between the pressure accumulating chamber 2 and the sleeve valve chamber 8 is closed.

  The valve bush 10 has an air passage 16 communicating the valve piston lower chamber 13 and the pressure accumulation chamber 2, an O-ring 18 intermittently connecting the air passage 17, and an O-ring 25 constantly closing the air passage 16 and the atmosphere.

  A sleeve valve portion 26 is provided on the outer periphery of the upper side of the cylinder 3. The sleeve valve portion 26 is fitted over the sleeve valve 19, the sleeve valve rubber 27 which connects and disconnects the pressure accumulation chamber 2 and the cylinder 3 from each other, and a sleeve valve. A sleeve valve spring 28 for urging the valve 19 toward the top dead center, and an air passage 29 fitted above the cylinder 3 for discharging compressed air above the piston 4a of the cylinder 3 is brought into and out of contact with the sleeve valve 19. An O-ring 31, an O-ring 32, and the like, which are fitted below the sleeve valve 19 and which always close the sleeve valve chamber 8 and the air passage 29, are provided.

  When the sleeve valve 19 is lowered, the sleeve valve 19 comes into contact with the exhaust bar 30 to close the air passage 29, and the pressure accumulating chamber 2 and the upper side of the piston 4a in the cylinder 3 communicate. As the sleeve valve 19 rises, the upper end of the cylinder 3 closes, and the sleeve valve 19 separates from the exhaust bar 30 to open the air passage 29. The air passage 29 communicates with the atmosphere via an air passage (not shown).

  A return air chamber 33 for storing compressed air for returning the driver blade 4 to the top dead center is provided on the outer periphery of the lower end of the cylinder 3, and an air passage 35 provided with a check valve 34 below the center in the axial direction and a lower portion of the cylinder 3 are provided below. Is provided with an air passage 36. A piston bumper 37 is provided at the lower end of the cylinder 3 for absorbing excess energy of the driver blade 4 after the nail 5 is driven.

  The operation portion 38 extends from the lower end of the nose 41 to the vicinity of the arm plate 40 from the trigger 39 operated by the operator, the arm plate 40 located between the trigger 39 and the plunger 7, and is urged toward the nose 41. A push lever 42 and the like that can move along 41 are provided. Therefore, as is well known, the plunger 7 is pushed up when both the pulling operation of the trigger 39 and the pressing operation of the push lever 42 against the material to be driven are performed.

  The ejection section 43 is provided with a feeding mechanism 45 for sequentially feeding the nails 5 loaded in the magazine 44 to the ejection port 41 in accordance with the reciprocating motion of the piston 4.

  The driving operation of the driving machine 1 having the above configuration will be described with reference to FIGS. 1 and 8 to 12.

  FIGS. 1 and 9 show a state in which an air hose is connected to the driving machine main body 1. The compressed air is stored in the pressure accumulating chamber 2. Part of the compressed air in the accumulator 2 flows into the valve piston lower chamber 13 via the air passages 17 and 16. The plunger 7 is located at the bottom dead center due to the pressure received by the diameter difference between the O-ring 15 and the O-ring 25 and the pressing force of the spring 12. A part of the compressed air in the accumulator 2 flows into the sleeve valve chamber 8 through the air passage 22. The sleeve valve 19 is located at the top dead center due to the diameter difference between the sleeve valve rubber 27 and the O-ring 46, the pressure received by the diameter difference between the O-rings 31 and 32, and the pressing force of the sleeve valve spring 28.

  The state at the moment when the plunger 7 is pushed up to the top dead center by performing both the pulling operation of the trigger 39 and the pressing operation of the push lever 42 against the material to be driven is shown in FIG. The air passage 16 is blocked by the O-ring 18, the seal of the O-ring 15 is released, the valve piston lower chamber 13 communicates with the atmosphere via the air passage 14, and the compressed air in the valve piston lower chamber 13 is exhausted.

  When the pressure in the valve piston lower chamber 13 becomes substantially atmospheric pressure, the valve piston 9 moves to the bottom dead center side against the pressing force of the spring 12 due to the received pressure due to the diameter difference between the O-ring 23 and the O-ring 24. The air passage 22 and the air passage 20 are shut off by the O-ring 23, the seal of the O-ring 21 is released, the atmosphere communicates with the sleeve valve chamber 8 via the air passage 20, and the compressed air in the sleeve valve chamber 8 is exhausted. . When the pressure in the sleeve valve chamber 8 becomes substantially atmospheric pressure, the sleeve valve 19 moves to the bottom dead center side against the pressing force of the sleeve valve spring 28 due to the pressure received by the diameter difference between the sleeve valve rubber 27 and the O-ring 46. First, when the pressure accumulating chamber 2 and the cylinder 3 communicate with each other, the sleeve valve 19 rapidly moves to the bottom dead center side due to the pressure received by the diameter difference between the O-ring 46 and the exhaust rubber 30.

  The exhaust bar 30 blocks the pressure accumulation chamber 2 and the cylinder 3 from the air passage 29. As shown in FIG. 8, the piston 4a strikes the nail 5 while rapidly moving to the bottom dead center side by the compressed air flowing from the pressure accumulating chamber 2 to the upper side of the piston 4a of the cylinder 3. The air below the piston 4a of the cylinder 3 flows into the return air chamber 33 via the air passage 36, and when the piston 4a passes through the air passage 35, a part of the compressed air above the piston 4a passes through the air passage 35. And flows back into the air chamber 33.

  FIG. 12 shows a state at the moment when the trigger 39 is returned or the operation of pressing the push lever 42 against the material to be driven is stopped and the plunger 7 is returned to the bottom dead center.

  The plunger 7 moves to the bottom dead center side by the receiving pressure due to the diameter difference between the O-ring 18 and the O-ring 25 and the pressing force of the spring 12. The air passage 14 is blocked by the O-ring 15, the seal of the O-ring 18 is released, and the compressed air in the accumulator 2 flows into the valve piston lower chamber 13 via the air passages 17 and 16.

  When the compressed air flows into the valve piston lower chamber 13, the valve piston 9 is top dead due to the pressure received by the diameter difference between the O-rings 23 and 24 and the diameter difference between the O-rings 15 and 24 and the pressing force of the spring 12. Move to the point side. The air passage 20 is cut off from the atmosphere by the O-ring 21, the pressure accumulating chamber 2 communicates with the sleeve valve chamber 8 via the air passage 22 and the air passage 20, and compressed air flows into the sleeve valve chamber 8.

  When the compressed air flows into the sleeve valve chamber 8, the sleeve valve 19 moves to the top dead center due to the pressure received by the diameter difference between the O-ring 31 and the O-ring 46 and the pressing force of the sleeve valve spring 28. The pressure accumulation chamber 2 and the cylinder 3 are shut off by the sleeve valve rubber 27, and the cylinder 3 and the atmosphere are communicated by the exhaust rubber 30. The lower side of the piston 4a is pressed by the compressed air accumulated in the return air chamber 33, and the piston 4a rapidly moves to the top dead center side. The air above the piston 4a is released to the atmosphere via the air passage 29, and returns to the initial state.

JP-B-58-50833

  As described above, the compressed air in the valve piston lower chamber 13 is exhausted through the air passage 14. As shown in FIG. 13, when the air is communicated with the air passage 14 and exhausted, the exhaust pressure may cause the O-ring 15 to fall out of the groove of the plunger 7. If the hardness of the O-ring 15 is increased so that it does not fall off, the sliding resistance between the valve piston 9 and the plunger 7 increases, which causes problems such as malfunction and difficulty in fitting the O-ring 15 to the plunger 7.

  The above-described phenomenon can also occur in the O-ring 18 fitted to the valve bush 10. That is, when the small-diameter portion located below the flange portion of the plunger 7 faces the O-ring 18 and the seal of the O-ring 18 is removed, the compressed air in the pressure accumulating chamber 2 passes through the air passages 17 and 16. Although it flows into the valve piston chamber 13, as shown in FIG. 14, the pressure of the compressed air may cause the O-ring 18 to fall out of the groove of the valve bush 10. As described above, if the hardness of the O-ring 18 is increased so that the O-ring 18 does not fall off, the sliding resistance between the valve bush 10 and the plunger 7 increases, causing a malfunction or difficulty in fitting the O-ring 18 to the valve bush 10. was there.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a driving machine which eliminates the above-mentioned problems and can prevent the O-ring from falling off without increasing the hardness of the O-ring.

  In order to achieve the above object, the present invention provides a cylindrical cylinder, a piston slidably supported in the cylinder, a driver blade formed integrally with the piston, Compressed air is supplied via, the driving machine having a sleeve valve portion that drives the piston, the trigger valve portion has a plunger that moves by a trigger operation, and a surface that slides with the plunger, A valve piston that moves in a direction opposite to the movement of the plunger, and a valve bush that has a surface that slides on the plunger and the valve piston, and that movably supports the plunger and the valve piston. One feature is that a seal member is provided on one side of the plunger which slides, and an uneven portion is provided on the other sliding surface. .

  Another feature of the present invention is that a cylindrical cylinder, a piston slidably supported in the cylinder, a driver blade formed integrally with the piston, and compression from a pressure accumulation chamber via a trigger valve portion. In a driving machine having a sleeve valve portion supplied with air and driving the piston, the trigger valve portion has a plunger that moves by a trigger operation, and a surface that slides on the plunger. And a valve bush that has a surface that slides on the plunger and the valve piston and that movably supports the plunger and the valve piston, and that slides on the valve bush. A seal member is provided on one of the plunger and / or the valve piston, and an uneven portion is provided on the other sliding surface.

  Advantageous Effects of Invention According to the present invention, it is possible to prevent the O-ring from falling off without increasing the hardness of the O-ring, and it is possible to prevent the sliding characteristics of the plunger and the fitting of the O-ring from being reduced. obtain.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 2 to 4. However, since there is almost no change except for the portion above the valve piston 9 described below, description other than the changed portion will be omitted.

  Above the valve piston 9 that faces the O-ring 15 when the plunger 7 is raised, a plurality of uneven portions 48 are formed, which are formed with unevenness intermittent in the radial direction along the circumferential direction. The convex portion 48a is formed to have a diameter that can guide the sliding of the O-ring 15, and the concave portion 48b is formed to have a diameter and width that can secure an area through which the compressed air in the valve piston lower chamber 13 can pass. 48b constitutes the air passage 14.

  As a result of the above configuration, when the O-ring 15 of the plunger 7 rises to the uneven portion 48 and the air passage 14 opens, the compressed air in the valve piston lower chamber 13 is discharged to the atmosphere via the concave portion 48b. At this time, the O-ring 15 receives a force to drop from the groove of the plunger 7 due to the exhaust pressure, but the O-ring 15 is prevented from dropping by the projection 48a. Therefore, it is possible to prevent the O-ring 15 from falling off without increasing the hardness of the O-ring 15, and it is possible to prevent the sliding characteristics of the plunger 7 and the fitting property of the O-ring 15 from being reduced.

  5 to 7 show another embodiment of the present invention, in which the O-ring 18 provided in the groove of the valve bush 10 is dropped from the groove of the valve bush 10 by the compressed air flowing into the lower chamber 13 of the valve piston. As shown in FIG. 7, the plunger 7 is provided with an uneven portion 58 composed of a concave portion 58 b and a convex portion 58 a extending along the axial direction. The bush 10 is prevented from falling out of the groove. The outer diameter of the convex portion 58a is formed so that the plunger 7 can slide with the O-ring 18 as a guide, and the diameter and width of the concave portion 58b are such that an area through which compressed air can flow into the valve piston lower chamber 13 can be secured. It is formed. Therefore, it is possible to prevent the O-ring 18 from falling off without increasing the hardness of the O-ring 18, and it is possible to prevent the sliding characteristics of the plunger 7 and the fitting property of the O-ring 18 from decreasing.

The partial section side view showing an example of a driving machine. FIG. 3 is a cross-sectional view showing an embodiment of the initial state of the trigger valve device of the present invention. Sectional drawing which shows the state which pushed up the plunger from FIG. FIG. 4 is a sectional view taken along line AA of FIG. 3. Sectional drawing which shows other embodiment of the initial state of the trigger valve apparatus of this invention. Sectional drawing which shows the state which pushed up the plunger from FIG. FIG. 6 is a sectional view taken along line BB of FIG. 5. Sectional drawing which shows the state which the piston was driven from the state of FIG. Sectional drawing which shows an example of the trigger valve apparatus before this invention. Sectional drawing which shows the state which pushed up the plunger from FIG. Sectional drawing which shows the state which the valve piston moved to the bottom dead center from FIG. Sectional drawing which shows the state which returned the plunger from FIG. FIG. 10 is a sectional view showing an operation state of the trigger valve device shown in FIG. 9. FIG. 10 is a sectional view showing an operation state of the trigger valve device shown in FIG. 9.

Explanation of reference numerals

1 is a driving machine main body, 2 is a pressure accumulating chamber, 6 is a trigger valve, 7 is a plunger, 9 is a valve piston, 10 and 11 are valve bushes, 12 is a spring, 13 is a valve piston lower chamber, 14 is an air passage, 15 , 18 are O-rings, 48 and 58 are concave and convex portions, 48a and 58a are convex portions, and 48b and 58b are concave portions.

Claims (4)

  A cylindrical cylinder, a piston slidably supported in the cylinder, a driver blade formed integrally with the piston, and compressed air supplied from a pressure accumulating chamber via a trigger valve unit, and the piston is In a driving machine having a sleeve valve portion to be driven, the trigger valve portion has a plunger that moves by a trigger operation, and a valve that has a surface that slides on the plunger and moves in a direction opposite to the movement of the plunger. A piston having a surface that slides on the plunger and the valve piston, and a valve bush that movably supports the plunger and the valve piston; and a seal member provided on one of the plungers sliding on the valve piston. A driving machine characterized in that an uneven portion is provided on the other sliding surface while being provided.   A cylindrical cylinder, a piston slidably supported in the cylinder, a driver blade formed integrally with the piston, and compressed air supplied from a pressure accumulating chamber via a trigger valve unit, and the piston is In a driving machine having a sleeve valve portion to be driven, the trigger valve portion has a plunger that moves by a trigger operation, and a valve that has a surface that slides on the plunger and moves in a direction opposite to the movement of the plunger. A piston having a surface that slides on the plunger and the valve piston, and a valve bush that movably supports the plunger and the valve piston, wherein the plunger and / or the valve piston slide on the valve bush; A driving machine characterized in that a sealing member is provided on one side and an uneven portion is provided on the other sliding surface.   3. The driving machine according to claim 1, wherein the protrusion is formed to have a diameter capable of guiding the seal member, and the recess is formed to have a diameter and width through which compressed air can pass. 3. The driving machine according to claim 1, wherein the uneven portion has a concave portion and a convex portion interrupted in a radial direction of the plunger, and has a shape extending in an axial direction.

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