JP3243882B2 - Compressed air screw tightening machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressed air screw tightening machine which consumes less compressed air.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a conventional screw tightening machine using compressed air as a power source. The inlet 5 intake compressed air connected to the compressed air source, b <br/> over data 1 a compressed air is supplied to Nyukiro 8 in street air motor motor 1 air motor 1 is rotated by pulling the operating valve 2 Then, the rotation of the rotor 1 is reduced by the gear 4 and the screw 13 is turned through the drive bit 3, and the screw 13 is screwed into the tightened member 30. The compressed air supplied into the air motor 1 passes through the exhaust path 6 and is exhausted into the atmosphere.
Release the operation valve 2 stops the supply of compressed air to the air motor 1, and ends curled stops the air motor 1.

[0003]

As described above, in the conventional compressed air screw tightening machine, the supply of the compressed air to the air motor 1 is stopped by operating the operation valve 2 by an operator. Therefore, since the operator closes the operation valve 2 after confirming that the screw 13 is completely screwed in, the compressed air is discharged wastefully until the operation valve 2 is closed after the screwing is completed, and the air consumption is reduced. There was a drawback that there were many.

On the other hand, in the construction field, as the amount of gypsum board used has increased, the amount of board screws used to stop the gypsum board has been increasing, and the demand for lightweight screw tighteners for tightening board screws has increased. I have. Conventionally, an electric screwdriver has been used, but since it is heavy, there is a strong demand for a lightweight compressed air screwdriver. However, in the case of using a compressed air screw tightening machine for construction, since the compressor serving as a compressed air source is portable and small, the conventional compressed air screw tightening machine cannot use a large amount of air. Therefore, there is a strong demand for the development of a compressed air screw tightening machine with low air consumption. SUMMARY OF THE INVENTION An object of the present invention is to provide a compressed air screw tightening machine which consumes less air and has a simple structure.

[0005]

SUMMARY OF THE INVENTION The above object is achieved by a air motor motor to rotate the compressed air as a power source, a drive bit for transmitting the rotation of the air motor to the screw, and inlet air passage for guiding the compressed air to the air motor, inlet air A compressed air screwdriver having an operable operation valve for controlling the supply of compressed air to a passage, wherein a moving member for moving a drive bit toward a material to be tightened by compressed air can be vertically moved into a cylinder. An air intake valve that opens or shuts off the inflow of compressed air into the air motor is provided in the air passage, and the compressed air in the cylinder that forms above the moving member when the moving member descends near the lowermost position. Achieved by connecting the air passage for introducing air to one end of the intake valve, moving the intake valve to the shutoff position by the compressed air flowing into the air passage, and stopping the supply of compressed air to the intake passage. Sa That.

[0006]

The compressed air screw tightening machine constructed as described above operates as follows. When the operating valve is operated, the compressed air is supplied to the air intake path, and the air motor rotates. At the same time, the compressed air is also supplied into the cylinder, and the moving member moves down in the cylinder, so that the drive bit moves toward the member to be tightened while rotating, and screws the screw into the member to be tightened. When the screwing is completed, that is, when the moving member descends to the vicinity of the lowermost position, the compressed air in the cylinder forming the upper portion of the moving member flows into the air passage, and the intake valve moves to a position where the intake passage is shut off. Then, the rotation of the air motor stops.

[0007]

FIG. 1 shows an embodiment of the present invention. Housing 7
The inlet 5 intake compressed air connected to a compressed air source, the compressed air and the air motor motor 1 supported by the housing 7 as rotating as a power source, formed in the housing 7, air motor
An air passage 8 for guiding compressed air to the air inlet 1, a main valve 11 for feeding and discharging compressed air to the air passage 8 and the cylinder 17, and a main valve 1.
1 has an operable valve 2 that can be operated to open and close. A moving member 14 having a piston portion at an upper portion is fitted in the cylinder 17 so as to be vertically movable, and a screw 13 is provided at a lower end portion thereof.
And the drive bit 3 for transmitting the rotation of the air motor 1, that is, the rotor 1 a to the screw 13, is formed integrally. The drive bit 3 is coupled to the rotor 1 a, for example, by a spline at the lower end of the rotor 1. A cylindrical intake valve 10 is fitted to the upper outer periphery of the cylinder 17 so as to be vertically movable, and is constantly urged downward by a spring 15. The upper end of the intake valve 10 faces the inside of the intake path 8. When the intake valve 10 rises to the vicinity of the uppermost end position, the intake path wall 9 is sealed and the intake path 8 is shut off. On the other hand, the lower end of the intake valve 10 has a larger pressure receiving area than the upper end, and is communicated with the cylinder 17 via the air passage 16. Opening 16a of air passage 16 on cylinder 17 side
Is provided at a position where compressed air in the cylinder 17 forming the upper part of the moving member 14 is introduced when the screwing of the screw 13 is completed, that is, when the moving member 14 is lowered to the lowermost position.

The operation of the above configuration will be described. When the compressed air inlet 5 is connected to the compressed air source and the operation valve 2 is operated, the air in the upper chamber of the main valve 11 is exhausted as shown in FIG. Inlet 8
Supplied to The compressed air passes through the air inlet 8 and the air motor 1
It is supplied to the rotor 1 a rotates. At the same time cylinder 1
The compressed air supplied to the upper part of the moving member 14 fitted in the moving member 7 lowers the rotating member 14 while rotating, and the drive bit 3 provided at the lower end of the moving member 14
, The screw 13 is rotated, and the screw 13 is
Screw in. At this time, as the screw 13 is screwed, the moving member 14 and the drive bit 3
Descending inside.

Next, as shown in FIG. 3, when the moving member 14 is lowered until the screw 13 is completely screwed in, the upper end of the moving member 14 is moved to the opening 16a formed in the inner wall surface of the cylinder 17.
Cylinder 17 above the moving member 14
Compressed air flows into the air passage 16 through the opening 16a, and the lower end of the intake valve 10 is pressurized. Eventually, the upward load caused by the pressure receiving area difference between the upper end and the lower end of the intake valve 10 overcomes the downward load of the spring 15 and raises the intake valve 10.
And shut off the air passage 8. Thus stops the supply of compressed air to the air motor 1, it stops the rotation of the air motor 1.

FIG. 4 shows another embodiment of the present invention. In the embodiment of FIGS. 1 to 3 described above, the cylindrical intake valve 10 is fitted to the outer periphery of the upper part of the cylinder 17, but in the embodiment of FIG. Airway 8 and air
The structure is such that the space between the motors 1 is cut off, and other structures, operations, effects, and the like are substantially the same as those in the above-described embodiment.

[0011]

According to the present invention, an intake valve for opening or shutting off the flow of compressed air into an air motor is provided in an intake path,
One end of the intake valve communicates with an air passage for introducing compressed air in a cylinder that forms above the moving member when the moving member descends near the lowermost position, and the compressed air that has flowed into the air passage is used as the intake valve. Is moved to the shut-off position, so that the supply of compressed air to the air motor can be automatically stopped at the same time that the screw has been screwed in, regardless of the operation of the operating valve. And the air consumption can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing one embodiment of a compressed air screw tightening machine of the present invention.

FIG. 2 is a side sectional view showing an operation state of FIG. 1;

FIG. 3 is a side sectional view showing an operation state of FIG. 1;

FIG. 4 is a side sectional view showing another embodiment of the compressed air screw tightening machine of the present invention.

FIG. 5 is a side sectional view showing an example of a conventional compressed air screw tightening machine.

[Explanation of symbols]

1 is an air motor, 1a is a rotor of the air motor 1 , 2 is an operation valve, 3 is a drive bit, 8 is an air intake passage, 10 is an air intake valve, 13 is a screw, 14 is a moving member, 16 is an air passage, 1
7 is a cylinder and 30 is a material to be tightened.

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B25B 21/00 B25B 23/02

Claims (1)

(57) [Claims] And 1. A Eamo <br/> over data for rotating the compressed air as a power source, and inlet air passage for guiding the drive bit, the compressed air to the air motor for transmitting the rotation of the air motor to the screw,
An operating valve for controlling supply of compressed air to the air passage, and a screwdriver for screwing a screw into a member to be tightened, wherein the drive bit is tightened with compressed air. A moving member that moves toward the material is fitted in the cylinder so as to be able to move up and down, and an air intake valve that opens or shuts off the inflow of compressed air to the air motor is provided in the air intake path. One end communicates with an air passage for introducing compressed air in the cylinder, which is formed above the moving member when the moving member is lowered to the vicinity of the lowermost position. A compressed air screw tightening machine characterized by moving a valve to a shut-off position.