WO2006101085A1

WO2006101085A1 - Air plug and compressed air tool

Info

Publication number: WO2006101085A1
Application number: PCT/JP2006/305577
Authority: WO
Inventors: Takumichi Hoshino; Masafumi Satsuka
Original assignee: Max Co., Ltd.
Priority date: 2005-03-24
Filing date: 2006-03-20
Publication date: 2006-09-28
Also published as: JP2006263877A

Abstract

An air plug (15) forming, together with a socket, a fluid coupling adapted to connect a compressed air tool to a compressed air feeding source, the compressed air tool having an air chamber (8) for containing compressed air fed from the compressed air feeding source, the capacity of the air chamber (8) being set equal to 90 cc or less. The outer diameter of a seal section (19) of the air plug (15) fitted in the socket is formed equal to 7.1 mm or less. An airflow path (20) that is formed in the center of the seal section (19) of the air plug (15) and through which compressed air flows from the socket side to the air plug (15) side is formed to a cross-section with a diameter of 3 mm or greater. The airflow path (20) is opened to an end surface of the seal section (19) with the same flow path cross-section kept.

Description

Specification

Air Bragg and compressed air tools

Technical field

The present invention relates to an air plug for connecting an air hose connecting a compressed air tool driven by compressed air and a compressed air supply source to the compressed air tool.

Background art

[0002] A compressed air drive nailing machine that drives a piston in a cylinder with compressed air and nails it with a driver connected to the piston, or an air motor driven by compressed air and a driver bit by this air motor Compressed air tools such as screwdrivers that rotate the screw to tighten screws are available. In such a compressed air tool, a compressed air supply source such as a compressor and the compressed air tool are connected via an air hose. The compressed air supplied from the compressed air supply source into the compressed air tool is introduced into the impact cylinder to drive the piston, or is supplied to the air motor to rotationally drive the air motor.

[0003] Between the compressed air tool and the air hose connecting the compressed air supply source, a compressed air tool, an air hose, a socket for connecting the air hose and the compressed air supply source, and an air plug are configured. Fluid coupling is used. In general, a socket containing a shutoff valve is formed at the end of an air hose connected to a compressed air supply source such as a compressor and a compressed air tool. An air plug connected to the socket is formed at the end of the air hose connected to the compressed air supply source and the compressed air tool. Compressed air supply by connecting an air plug formed on one end of the air hose to a socket of a compressed air supply source, and connecting a socket on the other end of the air hose to an air plug formed on the compressed air tool. Compressed air is supplied from the source to the compressed air tool.

[0004] Compressed air is supplied to the cylinder and driven by a piston to drive the nailing machine. The conventional nailing machine is driven by compressed air in the normal pressure range below IMPa, which has been used conventionally. In addition to the normal-pressure tool, it is driven with compressed air in a high-pressure range that is higher than the pressure in the conventional normal-pressure range. There is a compressed air tool dedicated to high pressure that can be moved (for example, Japanese Patent No. 3137229). High-pressure compressed air tools are used because high-power tools can be made compact and lightweight. The compressed air for driving the high-pressure tool is supplied from a compressed air supply source dedicated to high pressure. The fluid joint for connecting the high pressure tool and the high pressure compressed air supply source so that the normal pressure tool cannot be connected to the compressed air supply source dedicated to the high pressure is a fluid joint for the normal pressure tool. It is formed in a unique shape different from

[0005] In order to connect an air plug to a socket, it is necessary to insert a seal portion at the tip of the air plug into the socket. At this time, compressed air on the socket side acts on the end surface of the seal portion of the air plug, and an insertion load is generated that acts to separate the air plug from the socket. For example, when an air plug for normal pressure is used at a normal pressure of IMPa or less, the outer diameter of the seal part of the air plug is set so that this insertion load is 0.8 MPa or less. On the other hand, as shown in FIG. 7, in the air plug 40 of the fluid joint used in the compressed air tool in a high pressure range up to 2 MPa, for example, the compression acting on the end surface of the seal portion 41 fitted in the recess on the socket side is performed. The insertion load should be the same as that of the conventional air plug for normal pressure so that the mounting work load does not deteriorate due to high air pressure. For this reason, the outer diameter dimension al of the seal portion 41 of the air plug 40 used in the compressed air tool in the high pressure region is set small (diameter 7.1 mm).

[0006] Further, in a compressed air drive nailing machine that drives a piston with compressed air supplied into the cylinder, a large capacity (140 to 200 cc) air chamber is adjacent to the nailing machine cylinder. The compressed air supplied from the compressed air source is stored in the air chamber. A large amount of compressed air in the air chamber is instantaneously supplied into the cylinder, and the piston in the cylinder is driven in an impact manner. When a large-capacity air chamber is formed in the compressed air driven tool in this way, when the air hose connected to the compressed air supply source is removed from the tool, a large amount of compressed air is stored in the air chamber. Air blows out of the air plug and generates noise, or mechanical shake occurs due to reaction of the compressed air blowout. For this reason, in a conventional air plug mounted on a nailing machine driven by compressed air having a pressure in a high pressure region, as shown in FIG. The diameter cl of the air flow path 42 formed at the center of the seal portion 41 of the group 40 is set to about 3 mm, and a small hole 43 having a diameter bl of about 2 mm is formed at the end of the air flow path 42. As a result, the noise and reaction force caused by the compressed air ejected from the air plug 40 are made to be almost the same as those of a conventional normal pressure tool.

[0007] Impact that incorporates an air motor driven by compressed air, supplies compressed air to the air motor, rotates the driver bit connected to the air motor, and tightens the screw via the driver bit A compressed air tool such as a driver has a normal pressure tool, but a high pressure tool that is driven and driven by compressed air with a pressure in the high pressure range. In a tool in which a large amount of compressed air is continuously supplied to the air motor in order to drive such an air motor, the high-pressure air plug 40 having a small-diameter hole 43 formed at the tip is used for high pressure. When connected to a compressed air supply source, the small hole 43 at the tip acts as a throttle and cannot supply sufficient compressed air to the air motor, reducing the pressure of the compressed air supplied to the air motor and reducing the output of the air motor. As a result, there arises a problem that the workability of screw tightening is lowered.

Disclosure of the invention

[0008] One or more embodiments of the present invention provide an air plug for a compressed air tool capable of supplying a sufficient amount of compressed air to a compressed air tool or the like that drives an air motor without causing a pressure drop. To do.

[0009] An air plug for a compressed air tool according to one or more embodiments of the present invention includes an air chamber for storing compressed air supplied from a compressed air supply source, and the capacity of the air chamber is set to 90 cc or less. An air plug of a fluid joint composed of a socket and an air plug for connecting the compressed air tool to a compressed air supply source, and the outer diameter of the seal portion of the air plug fitted in the socket is 7. The air flow path formed in the center of the seal portion on the air plug side where compressed air flows from the socket side to the air plug side is formed in the flow path cross section of a hole having a diameter of 3 mm or more. The channel is opened at the end surface of the seal portion with the same channel cross section.

[0010] Further, according to one or more embodiments of the present invention, the diameter of the air flow path is smaller than 4.1 mm. [0011] An air plug for a compressed air tool according to one or more embodiments of the present invention includes an air chamber for storing compressed air supplied from a compressed air supply source, and the capacity of the air chamber is 90 cc or less. An air plug of a fluid joint composed of a socket and an air plug for connecting a compressed air tool set to a compressed air supply source, and the outer diameter of the seal portion of the air plug fitted into the socket. 7. In addition to forming 1 mm or less, an air flow path formed at the center of the seal part on the air plug side where compressed air flows from the socket side to the air plug side is formed in a flow path cross section with a diameter of 3 mm or more. In the compressed air tool with a chamber capacity of 90cc or less, such as an impact driver, the air channel is opened to the end face of the seal part with the same channel cross section. Even if the flow path diameter is increased, the amount of compressed air that is blown out from the tip of the air plug when the socket is removed from the air plug is small, so the generated sound and reaction force are small, and the operation is almost the same as that of a normal pressure compressed air tool. The ability to show off. In addition, the flow rate characteristics can be improved by enlarging the minimum flow path cross section of the air plug to the equivalent of a hole with a diameter of 3 mm, sufficient compressed air can be supplied to the air motor, and the pressure drop immediately before the air motor can be reduced. It is possible to drive with high output.

[0012] Other features and advantages will be apparent from the description of the examples and the appended claims.

Brief Description of Drawings

1 is a side view showing a part of an impact driver as an example of a compressed air tool equipped with an air plug of a typical embodiment of the present invention.

[Figure 2] Vertical side view of the air plug of Figure 1

FIG. 3 is a graph showing the relationship between the diameter of the air passage hole and the stress caused by the air plug of the typical embodiment of the present invention.

FIG. 4 is a graph showing the correspondence between the chamber volume and the exhaust sound by the air plug of the typical embodiment of the present invention.

FIG. 5 is a graph showing the correspondence between the chamber capacity and reaction force of the air plug of the exemplary embodiment of the present invention.

FIG. 6 is a graph showing the flow characteristics of an air plug of a typical embodiment of the present invention and a conventional air plug. [Fig.7] Longitudinal side view showing a conventional high-pressure air plug

Explanation of symbols

[0014] 1 Impact driver (compressed air tool)

8 Supply channel (Air chamber)

15 Air plug

16 Mounting part

17 Connection

18 Middle part

19 Seal part

20 Air flow path

21 opening

BEST MODE FOR CARRYING OUT THE INVENTION

[0015] Exemplary embodiments of the present invention will be described below with reference to the drawings.

Example 1

FIG. 1 is a side view showing an impact driver as an example of a compressed air tool that is operated with compressed air having a pressure in a high pressure range equipped with an air plug for high pressure according to the present invention, and a part of the impact driver. Is shown in cross section. The impact driver 1 has a housing 2 in which a grip portion 3 for gripping the impact driver 1 during work is formed. The housing 2 has a high pressure region supplied into the impact driver 1. An air motor 4 that is rotationally driven by compressed air is housed. Further, an impact mechanism driven by the air motor 4 is accommodated in the housing 2, and a drive shaft 5 driven to rotate by the impact mechanism is disposed so as to protrude from the tip of the housing 2, and this drive A chuck portion 6 on which a driver bit 7 is detachably attached is formed at the tip of the shaft 5.

[0017] The grip portion 3 formed integrally with the woozing 2 is formed in a hollow shape, and a supply flow for supplying compressed air to the air motor 4 is formed inside the hollow portion of the grip portion 3. A passage 8 and an exhaust passage 9 for discharging exhaust air exhausted from the air motor 4 after driving the air motor 4 to the atmosphere are formed in parallel. The base of the grip part 3 In this section, a throttle vano lev 10 for supplying the compressed air supplied to the supply flow path 8 to the air motor 4 is formed, and a throttle lever 11 rotatably supported at the base of the grip 3 is provided. By operating with the finger of the hand holding the grip portion 3, the compressed air supplied to the supply flow path 8 through the throttle valve 10 is supplied to the air motor 4 and supplied to the air motor. Rotate 4 to drive.

Compressed air supplied to the air motor 4 and driving the air motor 4 is exhausted from the air motor and introduced into the exhaust passage 9, and an exhaust portion formed at the rear end of the exhaust passage 9 Exhausted from 12 to the atmosphere. The exhaust section 12 is formed with an exhaust filter 13 for reducing the flow rate of the exhaust air exhausted from the air motor 4 to prevent the exhaust air from blowing up dust and wood chips and reducing the exhaust noise. Exhaust air exhausted from the air motor 4 is guided by the exhaust flow path 9, passes through the exhaust filter 13, and is discharged into the atmosphere from the exhaust port 14 formed in the exhaust part 12. .

[0019] An end portion of the supply flow path 8 is formed with an opening toward the rear end of the grip portion 3, and an air hose having one end connected to a compressed air supply source is detachably attached to the opening. An air plug 15 for connection is attached, and compressed air is supplied from a compressed air supply source into the supply flow path 8 formed in the grip portion 3 via an air hose connected to the air plug 15. The impact driver 1 of this embodiment is set to be operated by compressed air in a high pressure range higher than the pressure in the normal pressure range of IMPa or less. Therefore, the air plug 15 is connected to the compressed air supply system in the high pressure range. It is formed in a shape exclusively for high-pressure systems that can only be connected. The supply flow path 8 between the downstream side of the air plug 15 and the throttle valve 10 forms an air chamber having a small capacity of about 14 cc, and the compressed air supplied through the air plug 15 is this. It is formed by the supply flow path 8 and is stored in the air chamber.

[0020] As shown in FIG. 2, the air plug 15 that is effective in this embodiment is provided with an attachment portion 16 for attaching the air plug 15 to a tool such as an impact driver 1 and the like, and the air plug 15 is attached to one end of an air hose. A connecting portion 17 for connecting the socket, and an intermediate portion 18 rotatably connecting the mounting portion 16 and the connecting portion 17 along two planes disposed between them and inclined with respect to each other. And rotate each pivot connection independently. In this way, the connection part 17 of the air plug 15 can be freely directed in any direction with respect to the attachment part 16. The mounting portion 16 is formed with a male screw 22 for attaching the air plug 15 to the end portion of the grip portion of the impact driver 1 and is engaged with a tool for screwing the male screw 22 into engagement. Part 23 is formed.

[0021] The connecting portion 17 is formed with a hollow cylindrical seal portion 19 which is inserted into a recess formed in a socket attached to one end of the air hose. When the socket is inserted into the socket recess, compressed air on the socket side acts on the end face of the seal 19 to generate an insertion load, but the insertion of the compressed air does not exceed the specified value. The outer diameter dimension a2 is 7.1 mm, similar to the conventional air plug. The outer diameter dimension a2 of the seal portion 19 is a dimension common to an air plug used as an existing high-pressure dedicated compressed air supply system, and is supplied with compressed air from the existing high-pressure compressed air supply system. If received, this dimension cannot be changed.

[0022] At the center of the connection part 17 of the air plug 15, an air flow path that guides compressed air flowing from the socket side attached to the air hose into the supply flow path 8 in the grip part 3 through the mounting part 16. 20 is formed. The air flow path 20 is formed with an opening 21 along the central axis of the seal portion 19 at the end face of the seal portion 19 of the connection portion 17. Further, a plurality of openings 24 in the radial direction are formed at equal intervals in the circumferential direction on the outer peripheral surface close to the tip of the seal part 19, and the compressed air on the socket side passes through the openings 24. The air flows into the air flow path 20.

[0023] Since the outer diameter of the seal portion 19 is defined as 7.1 mm as described above, increasing the hole diameter of the air flow path 20 formed at the center of the seal portion 19 is not possible. This will reduce the strength of the tip of the connecting portion 17. The graph shown in Fig. 3 shows the stress generated in the seal part 19 when the same load as the weight of the impact driver 1 is applied to the tip of the connection part 17 from an angle of 45 degrees diagonally, corresponding to the hole diameter of the air flow path 20 From this graph, the stress does not change greatly when the hole diameter of the air flow path 20 is 2.0 to 4.1 mm. For example, even if the tool is dropped, the seal part 19 is damaged. I understood that it never happened. Therefore, in terms of strength, the hole diameter of the air flow path 20 formed in the seal portion 19 is the diameter 4. It can be increased to lmm.

[0024] In addition, the diameter of the air flow path 20 of the seal portion 19 is increased so that the air plug 15 force is compressed when the air hose connected to the compressed air supply source is removed from the air plug 15. It can be assumed that the eruption sound due to is increased. The graph shown in Fig. 4 shows that each of the air plug 15 with a hole diameter of the air flow path 20 set to 4. lmm and the conventional high-pressure air plug with a hole with a diameter of 2. Omm formed at the tip have a predetermined volume of air. The magnitude of the generated sound when the compressed air in the air chamber is ejected from each air plug connected to the chamber is shown in correspondence with the chamber capacity. From this graph, the hole of the air flow path 20 is shown. Even if the air plug 15 has a large diameter of 4.1 and the air chamber capacity is 90cc or less, the generated sound is almost the same as the generated sound of a tool equipped with an existing high-pressure air plug, and there is no practical problem. It was possible to measure the range. In particular, it can be understood that workability is not impaired at all when the air chamber capacity is as small as 14 cc as in the case of a tool for driving an air motor such as the impact driver 1 of this embodiment.

Furthermore, it can be assumed that the reaction force due to the compressed air ejected from the air plug 15 is increased by forming the diameter of the air flow path 20 of the seal portion 19 to be large. The graph shown in Fig. 5 has a predetermined capacity for each of an air plug 15 in which the hole diameter of the air flow path 20 is set to 4. lmm and a conventional high-pressure air plug in which a hole with a diameter of 2.0 mm is formed at the tip. This graph shows the magnitude of reaction force when compressed air in the air chamber is ejected from each air plug in correspondence with the chamber capacity. From this graph, the air flow path 20 Even with an air plug with a large hole diameter of 4.1, if the air chamber capacity is l lOcc or less, the reaction force is equal to or less than the reaction force of a tool equipped with an existing high-pressure air plug. It is thought that there is no title. In particular, as with tools that drive air motors, such as impact drivers, the workability is not impaired at all when the air chamber volume is as small as 14 cc or less.

[0026] As described above, in a compressed air tool such as an impact driver in which the chamber volume is smaller than 90 cc, for example, a chamber with a volume of about 14 cc, the hole diameter of the air flow path 20 of the air plug 15 is reduced to a diameter of 4. lmm. Even if it is formed large, when the air hose connected to the compressed air supply source is removed from the air plug 15, the amount of compressed air ejected from the air plug 15 is reduced. Therefore, the generated sound and reaction force can be reduced to less than or equal to those of compressed air tools with large capacity chambers that use existing air plugs. Compressed air driven by compressed air in the high pressure range Workability using tools is improved.

Furthermore, the graph shown in FIG. 6 is based on the air plug 15 in which the hole diameter of the air flow path 20 is set to 4.1 mm and the conventional high-pressure air plug in which a hole having a diameter of 2. Omm is formed at the tip. This graph shows the flow characteristics of high-pressure compressed air. From this graph, the conventional high-pressure air plug with a hole with a diameter of 2. Omm at the tip shows the secondary pressure downstream of the air plug as the flow rate increases. When the lOOOlZmin is large, the secondary pressure drops significantly to 1.5Mpa (decrease rate 17%). On the other hand, with the air plug 15 with the hole diameter of the air passage 20 set to 4.1mm, the secondary pressure It reduced secondary pressure even during Sukunagu 10001 / min is 1. 7 Mpa (reduction rate _6/0) and high pressure is found to be maintained. Thus, by improving the flow characteristics of the air plug, the air motor can be driven at a high output while maintaining the pressure of the compressed air in the high pressure region high. From the viewpoint of such flow characteristics, it is preferable that the hole diameter of the air flow path 20 and the diameter of the hole at the end of the air flow path be 3 mm or more. This is because if the hole diameter of the air channel 20 and the diameter of the hole at the tip of the air channel are small, for example, 2 mm, the pressure loss increases. The air channel 20 is preferably formed with the same channel cross section. This is because if the throttle element (for example, the small hole 43 at the tip in FIG. 7) exists in the air flow path, the pressure loss increases.

[0028] In the above embodiment, the attachment portion 16 and the connection portion 17 are pivotally connected to each other, and the intermediate portion 18 is configured to freely connect the connection portion 16 to the attachment portion in any direction. The force described based on the air plug 15 that can be directed to the present invention The present invention is not limited to this, but a male screw for attaching the air plug to the impact driver 1 is formed on one end side. And a hollow cylinder that is inserted into a recess formed in a socket attached to the air hose on the other end side. The same can be applied to an air plug in which a cylindrical seal portion is integrally formed. Further, the shape of the air flow path 20 is not limited to the hole shape. A shape similar to a non-coaxial hole or a polygonal shape such as a square hole may be used. [0029] According to the air plug 15 of the above embodiment, the compressed air tool that operates with the compressed air in the high-pressure range in which the volume of the air chamber that stores the compressed air supplied from the compressed air supply source is set to 90cc or less is provided. An air plug 15 of a fluid joint composed of a socket connected to a compressed air supply source and an air plug, and the outer diameter of the seal portion 19 of the air plug 15 fitted in a recess formed in the socket is changed to an existing air plug. The air flow path 20 formed at the center of the seal part 19 of the air plug 15 that allows the compressed air flowing from the socket side to the air plug 15 side to circulate is equivalent to a hole with a diameter of 3 mm or more. The air channel 20 is formed in the cross section of the flow path, and the air flow path 20 is opened to the end surface of the seal portion 19 with the same flow path cross section. Therefore, when the air hose is removed from the air plug 15, Since the amount of compressed air ejected from the bar is small, the generated sound and reaction force can exhibit almost the same operability as a normal pressure compressed air tool.

[0030] In addition, the air channel 20 is formed in a channel cross section corresponding to a hole having a diameter of 3 mm or more, and the air channel 20 is opened at the end surface of the seal portion 19 in the same channel cross section. The flow characteristics can be improved compared to conventional air plugs, and a sufficient amount of compressed air can be supplied to the air motor. The pressure drop immediately before the air motor can be reduced, and the air motor can be driven at high output. For example, when an impact driver whose effective cross-sectional area of the air flow path 20 is equivalent to a hole with a diameter of 3.8 mm is operated with compressed air with a pressure of 1.8 Mpa, the output of the motor increases by about 11%, The tightening time per screw was reduced by 15%, and the work efficiency of the screw tightening work was improved.

[0031] While 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.

[0032] This application is based on a Japanese patent application filed on March 24, 2005 (Japanese Patent Application No. 2005-086964), the contents of which are incorporated herein by reference.

Industrial applicability

[0033] An embodiment of the present invention provides an air plug that supplies a sufficient amount of compressed air to a compressed air tool or the like that drives an air motor without causing a pressure drop.

Claims

The scope of the claims

[1] A fluid coupling air plug composed of a socket and an air plug,

A seal part to be fitted in the socket;

An air flow path formed at the center of the seal portion and having the same flow path cross section and opening at the tip of the seal portion;

Comprising

The outer diameter of the seal portion is 7.1 mm or less,

The diameter of the air flow path is 3 mm or more.

Air plug.

[2] The air plug is attached to a compressed air tool including an air chamber for storing compressed air supplied from a compressed air supply source,

The capacity of the air chamber is 90 cc or less,

The air plug of claim 1.

[3] The air plug according to claim 1, wherein the diameter of the air flow path is smaller than 4.1 mm.

[4] an air chamber for storing compressed air supplied from a compressed air supply source;

An air plug for connection with a compressed air supply;

With

The air plug is

A seal part to be fitted in the socket;

Comprising

The outer diameter of the seal portion is 7.1 mm or less,

The diameter of the air flow path is 3 mm or more.

Compressed air tool.

5. The compressed air tool according to claim 4, wherein the capacity of the air chamber is 90 cc or less.

6. The compressed air tool according to claim 4, wherein the diameter of the air flow path is smaller than 4.1 mm.