WO2007049655A1

WO2007049655A1 - Pneumatic screw driving machine

Info

Publication number: WO2007049655A1
Application number: PCT/JP2006/321296
Authority: WO
Inventors: Makoto Kosuge; Masaki Haruta
Original assignee: Max Co., Ltd.
Priority date: 2005-10-26
Filing date: 2006-10-25
Publication date: 2007-05-03
Also published as: CN101296783A; JP2007118110A; JP4984487B2; CN101296783B

Abstract

A pneumatic screw driving machine comprises an air chamber for reserving a compressed air, a main valve supplying the compressed air reserved in the air chamber to a hammering cylinder, a driver bit for driving and tightening a screw, a valve housing provided in the main valve, and a valve body so provided as to be capable of vertically movable with respect to the valve housing. A through hole opening to the air chamber is formed in the valve housing; and a lower opening part opening to the hammering cylinder, a side opening part opening to the air chamber through the through hole, and a first air supply passage allowing the lower opening part to communicate with the side opening part are formed in the valve body. When the valve body is moved downward, a second air supply passage allowing the air chamber to communicate with the hammering cylinder through the through hole is formed between the outer peripheral surface of the valve body on the lower side of the side opening part and the inner peripheral surface of the valve housing.

Description

Specification

Pneumatic screw driving machine

Technical field

[0001] The present invention relates to a pneumatic screw driving machine.

Background art

[0002] Generally, in a pneumatic screw driving machine, a driving screw is lightly driven into a material to be driven and then tightened with tension. In accordance with such driving and screw tightening processes, the pneumatic screw driving machine is provided with a striking mechanism for striking the driving screw and a screw tightening mechanism for rotating the driving screw. The striking mechanism has a driver bit integrally coupled to a striking piston that is slidably accommodated in the striking cylinder, operates a main valve by the operation of a trigger, and an air chamber for storing compressed air with respect to the striking cylinder. Open and close, and supply compressed air to the striking cylinder to drive the striking piston. At the time of driving, it is necessary that the tip of the driving screw penetrates the upper material and is driven halfway to the ground.

However, since the supply amount of compressed air is always constant, the driving force by the striking piston is also always constant. For example, even if the upper material constituting the material to be driven is a gypsum board, the base is a wooden board or a steel plate. Since the wood board is softer than the steel plate, the energy required to penetrate the upper screw through the upper screw and drive it halfway through the wood plate may be smaller than that of the steel plate. However, it is not sufficient to pierce the steel plate with the tip of the driving screw with this driving energy. On the other hand, when the driving energy is matched to the steel plate, if the driving screw is driven into the base of the wooden board with this driving energy, the driving screw penetrates the wooden plate, or the displacement due to the reaction force of the screw driving machine, etc. This is disadvantageous in that the tip of the driver bit cannot be engaged with the head groove of the driving screw and screw tightening failure occurs.

[0004] Therefore, in order to improve the above inconvenience, an air supply port for supplying compressed air from the air chamber into the striking cylinder is formed in two stages, and a valve main body for selectively opening and closing these air supply ports is provided. The stroke of this nozzle body is changed by operating the external force, the pipe area is switched by this stroke difference, and the air supply amount to the striking cylinder is adjusted. There is a technique that can be adjusted (see, for example, Japanese Patent No. 3520443).

[0005] However, due to the deformation of the valve stopper and! /, Which suppresses the stroke of the valve body, even if the driving force is set to "Weak", the phenomenon of switching to "Strong" may occur. There was a problem that the total height was high or the number of parts was large. Disclosure of the invention

[0006] One or more embodiments of the present invention can adjust the driving force to ensure that the driving depth of the driving screw with respect to the material to be driven is appropriate, and further reduce the overall height of the tool. Providing a pneumatic screwdriver that can reduce the number of parts.

[0007] According to one or more embodiments of the present embodiment, the pneumatic screw driving machine supplies an air chamber that stores compressed air and the compressed air stored in the air chamber to the striking cylinder. A main valve, a driver bit that is integrally coupled to a striking piston provided inside the striking cylinder, and is screwed in and tightened, a valve housing that is disposed inside the main valve, and a bulging lower end are A valve body disposed in the valve housing and provided so as to be vertically movable with respect to the valve housing. The valve housing is formed with a through hole that opens to the air chamber. The valve body has a lower surface opening that opens to the striking cylinder, and a side opening that opens to the air chamber via the through hole. And a first air supply path that connects the lower surface opening and the side surface opening. When the valve body moves downward, the air chamber and the striking cylinder are connected between the outer peripheral surface of the valve body below the side opening and the inner peripheral surface of the valve housing via the through hole. A second air supply path that communicates is formed.

[0008] According to one or more embodiments of the present embodiment, the pneumatic screw driving machine further includes an operation lever provided on the upper portion of the tool body so as to be movable in the horizontal direction. The operating lever is formed with a stepped engaging groove having an upper engaging groove and a lower engaging groove formed along a horizontal direction, and an upper end of the valve body is formed in the stepped engaging groove. The valve body moves up and down by engaging and moving the operation lever in the horizontal direction.

[0009] According to one or more embodiments of the present embodiment, one end of the operation lever is a tool The other end can be swung to the left and right.

[0010] According to one or more embodiments of the present embodiment, the driver bit drives the screw so that the head of the screw floats against the workpiece, and then tightens the screw. Include.

[0011] According to one or more embodiments of the present embodiment, a throttle portion is formed in the noble housing, and the through hole is formed in an upper portion of the throttle portion.

[0012] According to one or more embodiments of the present embodiment, the pneumatic screwdriver further includes an o-ring attached to the outer peripheral surface of the valve body below the side opening. When the knob body moves up, the o-ring comes into contact with the inner peripheral surface of the valve blade and the udging.

[0013] According to one or more embodiments of the present embodiment, the pneumatic screwdriver further includes a piston stopper attached to a lower portion of the valve housing. The piston piston is maintained in a state where the striking piston has reached top dead center.

[0014] According to one or more embodiments of the present embodiment, the actuator further includes an operating shaft attached to an upper end of the noble body. The upper end of the valve body engages with the stepped engagement groove via the operating shaft.

[0015] According to one or more embodiments of the present embodiment, an inclined surface is formed between the upper engagement groove and the lower engagement groove.

According to one or more embodiments of the present embodiment, the operation lever includes an upper lever and a lower lever, and the upper lever and the lower lever are integrally coupled.

[0017] According to one or more embodiments of the present embodiment, when a large driving force is not required, the valve body is moved up, and compressed air is supplied only to the first air passage. Therefore, the driving force is relatively small. Therefore, the driving screw is driven to an appropriate driving depth in a soft base such as a wooden board. On the other hand, when a large driving force is required, the valve body is moved downward, and the inner peripheral surface force of the valve housing is also separated from the outer peripheral surface below the side opening. Thus, the compressed air, together with the first air supply path, is a gap between the outer peripheral surface of the bulging portion of the valve body and the inner peripheral surface of the valve housing, that is, the first air supply path.

Since it is supplied into the striking cylinder through the air supply path 2, a large driving force can be obtained. Therefore, the driving screw should have an appropriate driving depth even for a hard substrate such as a steel plate. Can be driven up to.

[0018] As described above, the switching operation of the switching valve composed of the valve housing and the valve main body selectively opens and closes the gap between the outer peripheral surface of the valve main body and the inner peripheral surface of the valve and the lousing, and is driven by a driver bit. The force can be adjusted according to the type of material to be driven, and the driving depth of the driving screw can always be adjusted appropriately.

[0019] Further, since the switching valve is disposed inside the main valve, the height of the entire tool can be kept low.

[0020] According to one or more embodiments of the present embodiment, the switching valve operating means includes an upper engagement groove and a lower engagement groove formed in the upper portion of the fixture body along the horizontal direction. An operation lever having a stepped engagement groove is provided so as to be movable in the horizontal direction, and the upper end of the valve body is engaged with the stepped engagement groove. Since it is performed by converting the horizontal movement of the lever, the driving depth of the driving screw that can be switched without permission can be surely made appropriate.

[0021] Furthermore, since the valve main body is directly switched by the operation lever, the number of parts can be reduced.

[0022] According to one or more embodiments of the present embodiment, one end of the operation lever is pivotally attached to the tool body, and the other end can be swung left and right. Easy.

Brief Description of Drawings

FIG. 1 is a plan view of an upper surface portion of a screw driving machine.

FIG. 2A is a cross-sectional view along the line XX of FIG. 1 showing the upper part of the screw driving machine with the main valve closed in a case where a large driving force is not required.

FIG. 2B is a cross-sectional view along the line XX of FIG. 1 showing the upper part of the screw driving machine in a state where the main valve is opened and a large driving force is not required.

FIG. 3A is a cross-sectional view taken along line YY of FIG. 1 showing an upper portion of the screw driving machine in a state where an operating shaft is engaged with an upper engaging groove.

FIG. 3B is a cross-sectional view taken along line YY of FIG. 1, showing the upper part of the screw driving machine in a state where the operating shaft is engaged with the lower engaging groove. 圆 4] An exploded perspective view of the driving adjustment mechanism.

FIG. 5A is a cross-sectional view taken along the line XX of FIG. 1, showing the upper part of the screw driving machine with the main valve closed when a large driving force is required.

FIG. 5B is a cross-sectional view taken along the line XX of FIG. 1 showing the upper part of the screw driving machine in a state where the main valve is opened when a large driving force is required.

FIG. 6A is a cross-sectional view showing the switching valve when the main valve is opened with the operating shaft engaged with the upper engagement groove in another embodiment.

FIG. 6B is a cross-sectional view showing the switching valve when the main valve is opened with the operating shaft engaged with the middle stage engaging groove in another embodiment.

FIG. 6C is a cross-sectional view showing the switching valve when the main valve is opened with the operating shaft engaged with the lower engaging groove in another embodiment.

Explanation of symbols

[0024] 1 stroke cylinder

2-stroke piston

5 Air chamber

9 Valve housing

10 Valve body

16 Air supply path

21-step engagement groove

22 Control lever

23 Engagement part (working shaft)

BEST MODE FOR CARRYING OUT THE INVENTION

[0025] FIG. 1 shows a top surface portion of the screw driving machine, and FIGS. 2A and 2B show cross sections on the line XX in FIG. This screw driving machine includes an impact mechanism and a screw tightening mechanism inside the tool body A. The striking mechanism has a striking cylinder 1, a striking piston 2 slidably provided in the striking cylinder 1, and a driver bit 3 integrally coupled to the striking piston 2, and pulls a trigger (not shown). To open the main valve 4 and operate the air cylinder (connected to the air supply source) 5 for storing compressed air. Compressed air is supplied inside and driver bit 3 is driven and operated. In addition, a screw tightening mechanism (not shown) tightens the driver bit 3 with power from an air motor or the like. That is, in the screw tightening mechanism, almost simultaneously with the start of the operation of the impact mechanism, the main valve 4 opens and operates to supply a part of the compressed air flowing in from the air chamber 5 to the air motor, and the driver bit 3 is attached to the shaft. Tighten the driving screw driven by the driver bit 3 by rotating it around the center.

[0026] The driver bit 3 hits the driving screw by the hitting mechanism and drives the driving screw so that the head of the driving screw floats against the material to be driven, and then tightens the driving screw by the screw tightening mechanism. See JP 2000-79569, JP-A-9-141571.

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A main valve 4 is disposed around the cylinder head portion of the striking cylinder 1. The main noble 4 is formed in an annular shape as shown in FIG. 4, and its lower end surface is provided so as to be engageable with the upper end of the inner wall of the air chamber 5 by sliding in the vertical direction. Normally, compressed air is supplied to the valve upper chamber 6, and the main valve 4 is lowered by the pressure of the compressed air and the panel 7, and its lower end is brought into contact with the upper end of the inner wall of the air chamber 5, whereby the air chamber 5 Is closed against the blow cylinder 1. On the other hand, the trigger valve (not shown) is operated by pulling the trigger to discharge the compressed air in the valve upper chamber 6 to move the main valve 4 upward as shown in FIG. 2B. The lower end separates the upper end force of the inner wall of the air channel 5, and the air chamber 5 is opened to the striking cylinder 1.

A driving force adjusting mechanism is provided in the inner space of the main valve 4. The driving force adjusting mechanism is composed of a switching valve 8 and operating means.

[0029] As shown in FIG. 2A and FIG. 4, the switching knob 8 is arranged in a tubular shape with a conical lower portion and a valve housing 9 that is passed through the valve housing 9 so as to be vertically movable. It also becomes a force with the shaft-shaped valve body 10 made. The upper part of the valve housing 9 is throttled, and a through hole 12 that leads to the air chamber 5 is formed in the upper part of the bracketed throttle part 11. The piston housing 13 is attached to the lower part of the nozzle housing 9 to hold the striking piston 2 when it reaches the top dead center.

[0030] Inside the valve housing 9, a valve body 10 is arranged to be movable up and down. . A shaft-like portion 14 is formed at the upper portion of the nozzle body 10 and a bulging portion 15 is formed at the lower end. An air supply path 16 is formed in the valve body 10 as a first air supply path. The upper portion of the air supply path 16 is open at the side surface of the base portion of the bulging projection 15. Further, the lower portion of the air supply path 16 is open to the lower surface. The side opening 17 opens to the air chamber 5 side through the through hole 12, and the lower surface opening 18 opens to the striking cylinder 1 side. An O-ring 20 is attached to the outer peripheral surface of the valve body 10 below the side opening 17!

[0031] Next, the valve body 10 is provided so that it can be moved up and down by operating means outside the tool body. That is, as shown in FIGS. 1, 3A and 4, the operating means is an operating lever 22 having two upper and lower stepped engaging grooves 21 formed horizontally on the upper part of the tool body A. . The operating lever 22 is provided so as to be movable in the horizontal direction, and an operating shaft 34 formed at the upper end of the noble body 10 is engaged with the stepped engaging groove 21.

[0032] The operation lever 22 is composed of an upper lever 22a and a lower lever 22b which are divided into upper and lower parts, and a stepped engagement formed in the width direction by combining two levers in the center. A groove 21 is arranged. The step between the upper engaging groove 21a and the lower engaging groove 21b of the stepped engaging groove 21 is an inclined surface 24. Further, a through hole 25 is opened in the center of the lower engaging groove 21b in the continuous direction of the stepped engaging groove 21. The operation lever 22 is disposed on the upper surface of the upper wall 27 of the cylinder cap 26 disposed above the striking cylinder 1, one end of which is pivotally attached to the support shaft 28 provided on the upper wall 27, and the other end. Is formed with a grip portion 29, which protrudes to the outside from the opening 32 (see FIG. 1) of the upper surface cover 31 fixed with a bolt 30 above the upper wall 27, so that the operating lever 22 is Attached so as to be swingable in the left-right direction along the upper surface of the horizontal upper wall 27.

[0033] In contrast, the shaft-like portion 14 of the valve body 10 of the switching valve 8 passes through the upper end of the valve housing 9, passes through the upper wall 27 of the cylinder cap 26, and further passes through the through-hole 25 of the lower lever. It penetrates and projects to the top. At the upper end, an operating shaft 34 is attached as an upper end engaging portion in a direction orthogonal to the axis of the shaft-like portion 14. The operating shaft 34 is disposed so as to engage with the stepped engaging groove 21 of the operation lever 22. Next, an operation mode of the driving force adjusting mechanism having the above configuration will be described. First, when the base material to be driven is a soft material such as a wood board and does not require a large driving force, the operation shaft 34 is stepped by rotating the operating lever 22 as shown in Fig. 3A. The upper stage of the engaging groove 21 is operated to engage with the engaging groove 21a. Since the valve body 10 of the switching valve 8 moves upward, as shown in FIG. 2A, the O-ring 20 on the outer peripheral surface below the side opening 17 of the valve body 10 is Abut. As a result, when the main valve 4 is opened and actuated as shown in FIG. The air is supplied into the striking cylinder 1 from the through hole 12 of 9 through the side surface opening 17 of the valve body 10 and from the lower surface opening 18 of the air supply path 16. The striking piston 2 is driven by the pressure of the compressed air as described above, and a driving screw is driven by the driver bit 3. Thus, since the compressed air is supplied with force only at the lower surface opening 18 of the air passage, the driving force is relatively small. Therefore, the driving screw is driven to an appropriate driving depth in the base wood board. Thereafter, the driving screw is tightened into the wooden board by the screw tightening mechanism.

On the other hand, when the substrate of the material to be driven requires a large driving force as in the case of a steel plate, the operating shaft 34 is rotated by rotating the operation lever 22 as shown in FIG. 3B. 21 Lower adjustment operation is performed to engage with the engaging groove 21b. Since the valve main body 10 of the switching valve 8 moves downward, as shown in FIG. 5A, the O-ring 20 on the outer peripheral surface below the side opening 17 of the valve main body 10 extends from the inner peripheral surface of the valve housing 9. Separate. As a result, when the trigger is pulled and the main valve 4 is opened and operated, the compressed air in the air chamber 5 passes through the opening of the valve housing 9 and the side opening of the valve body 10 as shown in FIG. 5B. The gas is supplied into the striking cylinder 1 through the lower surface opening 18 of the air supply passage 16 via 17. At the same time, the air that has passed through the through-hole 12 of the valve housing 9 passes through the gap 35 between the outer peripheral surface of the bulging projection 15 of the valve body 10 and the inner peripheral surface of the valve housing 9, and another air supply path 16a. Since it is supplied into the striking cylinder 1 from the (second air supply path), a large driving force can be obtained. Therefore, the driving screw can be driven to an appropriate driving depth with respect to the underlying steel plate. By the way, when the main valve 4 is closed and actuated by a trigger as shown in FIGS. 2A and 5A, the air chamber 5 is closed with respect to the striking cylinder 1 and at the same time the exhaust passage 36 (see FIGS. 2A and 2B). Therefore, the striking piston 2 moves up, and the compression air supplied into the striking cylinder 1 is discharged from the exhaust passage 36 to the outside. At this time, the inertia material 38 extends from the exhaust opening 37 at the top of the striking cylinder and is exhausted to the outside.

[0037] As described above, by the switching operation of the switching valve 8, the gap between the outer peripheral surface of the valve body 10 and the inner peripheral surface of the valve housing 9 is selectively opened and closed, and the driving force applied by the driver bit 3 is applied. It can be adjusted according to the type of driving material. With respect to the force, the stepping engagement groove 21 and the driving depth of the driving screw with respect to the workpiece can always be adjusted appropriately.

[0038] Further, since the vertical movement of the valve body 10 is performed by converting the horizontal swing motion of the operation lever 22, the operation of the driving screw is easy and the switching is not performed arbitrarily. The driving depth can be surely made appropriate.

[0039] Furthermore, since the switching valve is arranged inside the annular main nozzle, the overall height of the tool can be kept low.

[0040] Furthermore, since the valve main body 10 is directly switched by the operation lever 22, the number of parts can be reduced.

[0041] Although the embodiment of the driving force adjusting mechanism described above includes the operation lever 22 provided with the upper and lower two-stepped engaging grooves 21, the upper, middle and lower three-stepped steps are provided on the operation lever. You may comprise so that an engagement groove | channel may be provided. According to this, as shown in FIG. 6A, in the same manner as described above, the operating lever is rotated to engage the operating shaft of the valve body 10 of the switching valve with the upper engaging groove of the stepped engaging groove. By operating as described above, the compressed air in the air chamber is supplied from the through hole 12 of the valve housing 9 through the side opening 17 of the valve body 10 to the striking cylinder 1 from the lower surface opening 18 of the air supply path 16 at the time of startup. . Compressed air is supplied with force only at the bottom opening 18 of the air passage, so the driving force is relatively small!

[0042] Next, when the operation lever is operated so that the operating shaft of the valve body 10 is engaged with the middle engaging groove, the compressed air in the air chamber at the time of start-up is as shown in FIG. 6B. Opening of the lower surface of the air supply passage 16 from the through hole 12 through the side opening 17 of the valve body 10 Supplied into the blow cylinder from the part 18 and supplied into the blow cylinder from the air supply path 16a passing through the gap 35 between the outer peripheral surface of the bulging projection 15 of the valve body 10 and the inner peripheral surface of the valve housing 9. Therefore, a large driving force can be obtained.

[0043] Further, when the operation lever is operated to engage the operating shaft of the valve main body 10 with the lower engaging groove, the compressed air in the air chamber at the time of start-up is compressed in the valve housing 9 as shown in FIG. 6C. The force supplied from the through hole 12 to the inside of the impact cylinder 1 through the side surface opening 17 of the valve body 10 and through the lower surface opening 18 of the air supply path 16 and another air supply path 16b passing through the gap 35. Since the supply path 16b is larger than the air supply path 16a of FIG. 6B, a larger driving force can be obtained.

[0044] Although the invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. is there.

[0045] This application is based on a Japanese patent application filed on October 26, 2005 (Japanese Patent Application No. 2005-311295), the contents of which are incorporated herein by reference.

Industrial applicability

[0046] In the pneumatic screw driving machine, the driving force can be adjusted to ensure that the driving screw driving depth is appropriate.

Claims

The scope of the claims

[1] an air chamber for storing compressed air;

A main valve that supplies compressed air stored in the air chamber to a striking cylinder; a driver bit that is integrally coupled to a striking piston provided in the striking cylinder;

A valve housing provided inside the main valve;

A bulging lower end is disposed in the valve housing, and is provided with a valve body that is vertically movable with respect to the valve housing;

The nove housing is formed with a through hole that opens to the air chamber, the valve body has a lower surface opening that opens to the striking cylinder, and a side opening that opens to the air chamber through the through hole. And a first air supply path that communicates the lower surface opening and the side surface opening,

When the valve main body is moved downward, the air chamber, the striking cylinder, Pneumatic screw driving machine in which a second air supply path is formed to communicate with each other.

[2] An operation lever provided in the upper part of the tool body so as to be movable in the horizontal direction is further provided, and the operation lever has an upper engagement groove and a lower engagement groove formed along the horizontal direction. A stepped engagement groove is formed,

The upper end of the valve body engages with the stepped engagement groove,

The valve body moves up and down by moving the operation lever in the horizontal direction.

The pneumatic screw driving machine according to claim 1.

3. The pneumatic screw driving machine according to claim 2, wherein one end of the operation lever is pivotally attached to the tool body, and the other end is swingable left and right.

[4] The pneumatic screw driving machine according to claim 1, wherein the screwdriver bit tightens the screw after driving the screw so that the head of the screw floats against the material to be driven.

[5] The throttle housing is formed with a throttle portion, The pneumatic screw driving machine according to claim 1, wherein the through hole is formed in an upper part of the throttle portion.

[6] It further comprises an O-ring attached to the outer peripheral surface of the valve body below the side opening,

2. The pneumatic screw driving machine according to claim 1, wherein when the nozzle body moves up, the O-ring comes into contact with an inner peripheral surface of the valve blade and the udging.

7. The pneumatic screw driving machine according to claim 1, further comprising a piston stopper attached to a lower part of the valve housing, wherein the piston stopper holds a state where the striking piston has reached a top dead center. .

[8] It further comprises an operating shaft attached to the upper end of the valve body,

The pneumatic screw driving machine according to claim 2, wherein an upper end of the valve main body is engaged with the stepped engagement groove via the operation shaft.

9. The pneumatic screw driving machine according to claim 2, wherein an inclined surface is formed between the upper engagement groove and the lower engagement groove.

[10] The operation lever includes an upper lever and a lower lever,

The pneumatic screw driving machine according to claim 2, wherein the upper lever and the lower lever are integrally coupled.