JPS646214Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a nailing machine configured to drive a nail into a surface to be driven by a driver driven by air pressure. The present invention relates to an operating valve mechanism for controlling drive.

Conventionally, in this type of valve mechanism, as shown in FIG. A spherical valve body v that is pushed and operated is loosely fitted into the valve seat b so that it can be closed, and the flow of air in the handle h is controlled by the contact and separation of the valve body v and the valve seat b. In this case, the valve body v is always pressurized downward by the air, and the operation of the valve body v is affected by the air pressure, so when tilting the trigger t to move the valve body v upward, excessive pressure is applied. Pressure may be required, or the pressing force may vary depending on air pressure.
There was a drawback that the opening/closing operation of the valve body v became uncertain, resulting in variations in the driving force of the nail.

In view of the above-mentioned drawbacks, the purpose of the present invention is to provide an operating valve for a nailing machine that can operate reliably and smoothly by eliminating the influence of air pressure fluctuations, and can also eliminate malfunctions such as double-driving of nails. It is to provide a mechanism.

Next, an embodiment of the present invention will be described with reference to the drawings. In the drawing, 1 is a housing of the nailing machine main body K, 2 is an upcap cap that covers the upper end of the housing 1, and 3 is a cap vertically installed in the housing 1. a substantially cylindrical cylinder 4, a piston 4 tightly fitted in the cylinder 3 so as to be able to slide up and down; 5 a piston 5 that is movably attached to the piston 4 and extends downward for driving a nail; 6 is a main valve fitted externally to be able to slide up and down near the upper end of the cylinder 3; 7 is a hollow handle protruding from the right side of the housing 1; An air supply chamber 9 is formed for supplying compressed air supplied from an air supply source (not shown) to a pressurizing chamber 8 formed above the piston 4 in the cylinder 3 when the driver 5 is driven.

A trigger 10 is tiltably supported by a support member 11 arranged below the handle 7 on the side surface of the housing 1, and an idler 10a is tiltably pinned thereto.

Reference numeral 12 denotes a flow path bent in an L-shape along the side surface of the cylinder 3 and the peripheral wall 7a at the lower end of the handle 7 to supply and exhaust air for operating the main valve 6, and is a flow path formed in an L-shape along the side surface of the cylinder 3 and the peripheral wall 7a at the lower end of the handle 7. When the air flows into the flow passage 12, the main valve 6 moves upward, the air in the air supply chamber 9 flows into the pressurizing chamber 8 through the ventilation holes 27 and 28, and the piston 4 moves downward together with the driver 5. On the other hand, when the air in the flow path 12 is discharged, the main valve 6 moves down and the pressurizing chamber 8 is cut off from the air supply chamber 9, and the pressure inside the pressurizing chamber 8 is reduced and the piston is driven out. 4 A return chamber 1 formed at the lower part of the outer periphery of the cylinder 3 with respect to the inside of the lower cylinder chamber 3a.
Air in the piston 3 flows in, and the piston 4 moves upward together with the driver 5 to return to its original position.

Next, a description will be given of a valve mechanism for controlling the inflow of air in the air supply chamber 9 into the flow path 12 and the discharge of the air in the flow path 12 to the outside air.
Reference numeral 14 denotes a substantially closed cylindrical valve case that is attached to the peripheral wall 7a at the lower end near the base end of the handle 7, facing the trigger 10, and a valve cap 14a is sealed at the upper end with an O-ring 15. On the other hand, an exhaust port 16 is formed in a step shape at the lower end, and upper communication ports 17, 17 arranged in the air supply chamber 9 are provided in the circumferential body portion 14b having a step-like inner peripheral surface. and lower communication ports 18, 18 disposed within the flow path 12, respectively.

Reference numeral 19 denotes a valve stem that is tightly fitted into the valve case 14 so as to be able to slide up and down, and is sealed with O-rings 20, 20.
A water diameter portion 19a is tightly fitted to the inner upper portion via the slide surface 25, and a water diameter portion 19a is formed in a slightly stepped shape to fit tightly into the exhaust port 16 or to penetrate through the gap 26. In addition, the upper hole 22a of the hole 22 is formed into a substantially stepped cylindrical shape by the small diameter portion 19b around which the O-ring 21 for sealing is wound, and is normally recessed in a step shape with respect to the large diameter portion 19a. A spring 23 interposed between the valve cap 14a and the valve cap 14a.
, the tip of the small diameter portion 19b is urged downward so as to protrude from the exhaust port 16 of the valve case 14;
Furthermore, a through hole 24 communicating with the lower hole 22b of the hole portion 22 is provided near the base end of the small diameter portion 19b. When the trigger 10 is tilted upward to move the valve stem 19 upward, the exhaust port 16 is closed by the small diameter portion 19b of the valve stem 19, and the upper communication port 17 is opened, so that the air in the air supply chamber 9 is discharged. It flows into the flow path 12 through the upper and lower communication ports 17 and 18. At this time, part of the air flowing in the flow path between the upper and lower communication ports 17 and 18 flows into the hole 22 through the through hole 24 (see FIG. 4), and A part of the air flowing in the flow path is caused by the large diameter portion 1 of the valve stem 19.
The valve stem 19 is pressurized upward by applying pressure to the lower surface of the valve stem 9a. On the other hand, when the trigger 10 is released to move the valve stem 19 downward, the large diameter portion 19a
The sliding surface 25 of the valve stem 19 closes the upper communication port 17 and blocks the air supply chamber 9 and the flow passage 12 (see FIG. 3), and the sliding surface 25 of the valve stem 19 is rotated centripetally by the air in the air supply chamber 9. The pressurizing force in the sliding direction applied to the valve stem 19 by the air in the air supply chamber 9 is eliminated, and the flow passage 12 is also The air in the flow path 12 is communicated with the outside air through the clearance 26, and the air inside the flow passage 12 is discharged through the clearance 26. At this time, the air in the hole 22 is discharged to the outside of the valve stem 19 through the through hole 24, but since the flow rate of air flowing through the through hole 24 is restricted, the valve stem 19 The air in the section 22 and the spring 23
The valve stem 19 can be pressurized downward by the above, and the valve stem 19 can be moved downward rapidly.

Next, the operation and effects of the embodiment having the above configuration will be explained.

In this example, a substantially covered cylindrical valve case 14, which is attached to the peripheral wall of an air supply chamber 9 for supplying air to drive a nailing driver 5, facing an operating trigger 10, is supplied with air. An upper communication port 17 that communicates between the air chamber 9 and the inside of the valve case 14, and a driver 5.
A lower communication port 18 that communicates the inside of the valve case 14 with the flow path 12 through which air is distributed to control the operation of the valve case 14 is opened, and a large diameter portion 19a that opens and closes the upper communication port 17 is provided in the valve case 14. A valve stem in which a small diameter part 19b for opening and closing an exhaust port 16 opened at the lower end of a valve case 14 is connected in a vertically stepped manner, a hole part 22 that opens upward is recessed, and the valve stem is biased downward by a spring 23. 19 is fitted in a vertically slidable manner, and furthermore, the small diameter portion 19b communicates the flow path between the upper and lower communication ports 17 and 18 with the inside of the hole 22, so that when the valve stem 19 moves upward, the upper and lower communication ports 1
A through hole 24 is provided through which a part of the air flowing in the flow path between 7 and 18 flows into the hole 22.

Therefore, by tilting the trigger 10 upward, the valve stem 19 is moved upward, and the air supply chamber 9 and the flow passage 1 are moved upward.
2, a part of the air that flows in from the air supply chamber 9 and flows through the flow path between the upper and lower communication ports 17 and 18 passes through the through hole 24 to the valve stem 19.
At the same time, the upper and lower communication ports 1
A portion of the air flowing in the flow path between the valve stem 19 and the trigger 10 pressurizes the valve stem 19 upward.
When opening the upper communication port 17 to lower the valve stem 19 and communicate the flow passage 12 with the outside air, the upper communication port 17 is opened.
is closed by the large diameter portion 19a, and the pressure in the sliding direction applied to the valve stem 19 by the air in the air supply chamber 9 is eliminated, and the hole into which the valve stem 19 flows through the through hole 24 is removed. The valve stem 19 is pressurized downward by the air in the portion 22 and the spring 23, and the valve stem 19 moves downward rapidly. Therefore, the influence of fluctuations in air pressure within the air supply chamber 9 and the influence of the operating force for tilting the trigger 10 can be eliminated, and the operation of the valve stem 19 can be accelerated and stabilized.

Therefore, the vertical sliding movement of the valve stem 19 can be made more precise and smoother, and the valve structure can be simplified.

When the upper communication port 17 is opened, a large amount of air is sent from the air supply chamber 9 to the flow path 12, thereby speeding up the operation of the main valve 6 that follows the valve stem 19. When the valve stem closes the open exhaust port 16 and moves upward by a predetermined distance, it opens the closed upper communication port 17, and the valve stem 19 at the upper moving end opens the open upper communication port 17. This is because the closed exhaust port 16 is set to open when the exhaust port 16 moves further down a predetermined distance after being closed, and the opening/closing time of the exhaust port 16 and the opening/closing time of the upper communication port 17 are shifted back and forth. , the flow direction of the air in the flow path 12 is reliably changed, and there is an effect that malfunctions such as double hammering of nails caused by uncertain opening/closing operations when switching the flow path can be prevented.

That is, in the present invention, the air supply is provided in a substantially covered cylindrical valve case that is attached to the peripheral wall of an air supply chamber facing an operating trigger for supplying air to drive a nail driver. An upper communication port that communicates between the chamber and the inside of the valve case, and a lower communication port that communicates the inside of the valve case with a flow passage through which air for controlling the operation of the driver flows, and the inside of the valve case. A large diameter portion for opening and closing the upper communication port and a small diameter portion for opening and closing the exhaust port opened at the lower end of the valve case are connected in a vertically stepped manner, and a hole portion opening upward is recessed. A valve stem biased downward by a spring is fitted so as to be slidable up and down, and further, a flow path between the upper and lower communication ports is communicated with the inside of the hole in the small diameter portion, so that when the valve stem moves upward, the valve stem is inserted into the small diameter portion. By providing a through hole through which a part of the air flowing in the flow path between the upper and lower communication ports flows into the hole, the flow path between the upper and lower communication ports is flowed when the valve stem moves upward. While the valve stem is pressurized upward by a portion of the circulating air, when the trigger valve moves downward, the upper communication port is closed by the large diameter part of the valve stem, and the air pressure in the air supply chamber affects the valve stem. In addition, the valve stem can be pressurized downward by the air flowing into the hole through the through hole and the spring to rapidly move the valve stem downward, and the air pressure in the air supply chamber can be eliminated. This has the effect of speeding up and stabilizing the operation of the valve stem by eliminating the influence of fluctuations in the pressure and the operating force for operating the trigger.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing the valve mechanism of a conventional nailing machine, Figs. 2 to 4 show an embodiment of the present invention, and Fig. 2 is a longitudinal cross-section of the main parts of the nailing machine. Figure, 3rd
The figure is an enlarged longitudinal cross-sectional view of the valve mechanism, and FIG. 4 is an enlarged longitudinal cross-sectional view of the same during nailing. 5...Driver, 9...Air supply chamber, 10...Trigger, 12...Flow passage, 14...Valve case, 1
6...Exhaust port, 17...Upper communication port, 19...Valve stem, 25...Sliding surface.

Claims (1)

[Scope of utility model registration request] The air supply chamber and the valve case are attached to the peripheral wall of the air supply chamber for supplying air to drive the nail driver, and the valve case has a substantially closed cylindrical shape and is attached opposite to the operating trigger. An upper communication port that communicates with the inside of the valve case, and a lower communication port that communicates the inside of the valve case with a flow path through which air for controlling the operation of the driver flows, and an upper communication port that communicates with the inside of the valve case. A large diameter part that opens and closes the mouth and a small diameter part that opens and closes the exhaust port opened at the lower end of the valve case are connected in a vertically stepped manner, and the upward opening hole is recessed and is attached downward by a spring. The energized valve stem is fitted so as to be vertically slidable, and further, the small diameter portion communicates the flow path between the upper and lower communication ports with the inside of the hole so that when the valve stem moves upward, air flows in from the air supply chamber. An operation valve mechanism for a nailing machine, characterized in that a through hole is provided through the hole through which a part of the air flowing in the flow path between the upper and lower communication ports flows into the hole.