JPH0911147A - Pulse wrench for stud - Google Patents

Abstract

PURPOSE: To easily set a stud bolt by automatically switching normal rotation to reverse rotation by a set torque and holding it by itself. CONSTITUTION: In a pulse wrench for rotationally moving a main shaft by turning movement of a rotor via a hydraulic impact torque generator, a rod 15 penetrating through a rotor shaft 4 and detecting a set pressure in the torque generator 5 so as to operate it is provided. The end of this rod 15 is brought in contact with a valve 20 supported by a spring pressure. A switch valve 3 provided in a pulse wrench and a chamber providing a valve 32, which is released by pressurization of the rod 15, are communicated with each other and air pressure is applied on the both ends of the valve 32 for normal/reverse switching provided in this switch valve 3. The switch valve 3 is switched via the rod valve in generation of set torque of the main shaft 7, the air is supplied in the rotor inverse rotation direction so as to rotate inversely, and this inverse rotation is held during opening of the main valve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stud wrench for a stud, which can be easily planted with a stud bolt by automatically switching from normal rotation to reverse rotation at a set torque and self-holding. It is a thing.

[0002]

2. Description of the Related Art A pulse wrench for a stud rotates forward with high pressure air supplied by opening a main valve, tightens a stud bolt, and when a set torque is reached, a reverse rotation switching valve provided in the pulse wrench. Is manually switched to remove the tightening socket from the planted stud bolt.

[0003]

Therefore, in the conventional pulse wrench, it is necessary to manually switch the attached switching valve every time the set torque is reached, and the workability is poor.

It is an object of the present invention to automatically switch to reverse rotation when the set torque is reached, and self-hold it to improve its operability.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and is a pulse wrench in which a main shaft is rotated by a rotation of a rotor via a hydraulic striking torque generating device. , A rod that penetrates the rotor shaft and that operates by detecting the set pressure in the torque generator,
The rear end of this rod is brought into contact with the valve supported by the spring pressure, and the switching valve provided in the pulse wrench and the chamber provided with the valve that is released by the pressing of the rod are electrically connected to each other. Air pressure is applied to both ends of the provided valve for forward / reverse switching, and when the set torque of the main shaft occurs, the switching valve is switched via the rod valve to supply air in the reverse rotation direction of the rotor and reverse rotation. The gist of the present invention is that this reverse rotation is maintained when the valve is opened.

[0006]

A rod which penetrates the rotor shaft and operates by detecting the set pressure in the torque generator is provided, and the rear end of this rod is brought into contact with the valve supported by the spring pressure and is also installed in the pulse wrench. The provided switching valve is electrically connected to the chamber in which the valve that is released by pressing the rod is provided, and air pressure is applied to both ends of the valve for forward / reverse switching provided in this switching valve to generate the set torque of the spindle. The switching valve is switched via the rod valve, and air is supplied in the reverse rotation direction of the rotor for reverse rotation. With this, since the main valve is automatically opened and the pulse wrench is pressed, the right rotation is automatically switched to the left rotation, so that the operation is easy and the operation is reliable.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pulse wrench for a stud according to the present invention will be described below with reference to the illustrated embodiments. In the figure, reference numeral 1 denotes a main body of a hydraulic torque wrench, in which a main valve 2 for manually supplying and stopping high-pressure air and a switching valve 32 for automatically switching to reverse rotation at a set torque are provided. The rotor 4 is provided in the main body 1 so that the high-pressure air sent from the main valve and the switching valve generates a rotational torque, and has a motor structure of a general pneumatic tool. The hydraulic chamber striking torque generator 5 for converting the rotational torque of the rotor 4 into striking torque is provided in the front case 6 projecting from the tip of the main body 1.

This hydraulic percussion torque generator 5 is provided with a liner 8 inside the liner case 12 which is eccentric with respect to the main shaft 7 so as to be rotatable with respect to the main shaft 7, and generates a torque in the liner 8. The main shaft 7 is filled with air-tight oil and sealed, and two blade insertion grooves 7b, 7b facing each other on the diameter line passing through the center are provided in the main shaft 7, and springs S are always projected in the outer peripheral direction of the main shaft in each groove. In addition, the blade 9 having a thickness smaller than the groove width is fitted and provided, and the outer peripheral surface of the main shaft between the two blades 9 and 9 is provided with sealing surfaces 7a, 7a slightly protruding from the outer end surface of the main shaft. However, the straight line connecting the two sealing surfaces 7a, 7a shall be closer to either one of the center lines with a certain distance from the straight line passing through the center of the main axis in parallel therewith, and the center line, A straight line connecting the center of the spindle and the seal surface Those formed by the required angle.

A liner 8 fitted with a main shaft 7 provided with two blades 9 projecting in opposite directions forms a liner chamber having a cocoon-shaped cross section as shown in detail in FIG. The inner peripheral surface of the constricted portion is protruded in a mountain shape from the inner peripheral surfaces of the other portions to form the seal surfaces 8a and 8b. Of the sealing surfaces 8a and 8b provided on the inner circumferential surface of the oval cavity, the two sealing surfaces 8b and 8b facing in the cavity long axis direction are located on a straight line passing through the center of the cavity, but are facing in the minor axis direction. The two sealing surfaces 8a, 8a
The cavity short axis, the cavity center and the seal on the straight line parallel to the minor axis that is displaced by a certain distance to the right or left of the minor axis passing through the center of the cavity (the direction is displaced by the rotation of the liner) The straight line connecting the point 8a and the straight line connecting the points 8a are determined so as to form a required angle. Therefore, the distances between the sealing surfaces 8a and 8b provided at four locations on the inner peripheral surface of the cavity in the circumferential direction of the cavity sandwich the long axis of the cavity. That is, on both sides, the intervals of the sealing surfaces facing each other via the major axis are equal, but the intervals of the sealing surfaces facing each other via the minor axis are unequal.

The seal surface 8a is brought into contact with or close to the seal surface 7a of the main shaft 7 when the liner 8 rotates around the outer periphery of the main shaft 7 fitted in the liner chamber.
The chambers a and 8a are hermetically sealed so as to divide the chamber into two. Then, the liner chamber is brought into contact with the tip of the vane 9 at an intermediate position between the two opposing seal faces of the inner peripheral surface of the liner 8 to form the liner chamber with the two vanes 9 and the both seal faces 7.
A mountain-shaped sealing surface 8b is formed by a and 8a so as to be temporarily divided into two chambers or four chambers. The two sealing surfaces 8b and 8b are formed in a straight line passing through the centers of the chambers. They are arranged opposite each other. Further, an output adjusting valve insertion hole 10 is bored in one sealing surface 8b of the liner 8 in parallel with the liner chamber, that is, in parallel with the axis of the liner, and the mountain-shaped sealing surface is formed in the inner portion of the hole 10. Ports P1 and P2 are formed between at least two chambers divided by the sealing surface of the main shaft and blades with 8b interposed therebetween, and the output adjustment valve insertion hole 10 is electrically connected, and the output adjustment is performed in the hole 10. The relief valve shaft 11 and the relief valve B for performing the above are adjustably fitted.

The relief valve shaft 11 is screwed into the liner lower lid 14 so that the relief valve shaft 11 can be rotated and adjusted from the outside of the liner lower lid 14, and a groove 11a is formed on the outer periphery of the relief valve shaft 11. A passage 11b is formed which opens from the peripheral surface of the groove 11a to the tip surface of the relief valve shaft and is electrically connected. Then, the relief valve B is arranged so as to be pressed against the opening of the tip end surface of the relief valve shaft of the passage 11b by spring pressure. The relief valve B is configured to be pressed against the relief valve shaft 11 side with a required pressing force by a spring 11c fitted and supported in a recess 13a formed in the liner upper lid 13.

A hole is penetrated through the shaft center of the rotor 4, and a rod 15 is slidably fitted in the hole.
A piston 16 is integrally provided at the tip of the piston 1.
6 is fitted in a cylinder 17 provided in the liner upper lid, the tip of the piston 16 is made to face the end surface of the main shaft 7 facing the liner upper lid 13, and the main shaft end surface is inserted into the recess of the liner upper lid. A fine gap is formed between the inner bottom surface of the recess and the end face of the spindle, and this is used as a pressure detection cylinder 13d, and a small diameter passage 13b is provided to connect the cylinder 13d and the recess 13a of the liner upper lid. Further, a valve switching mechanism 18 is arranged at the other end of the rod 15, and movement of the rod 15 activates this valve switching mechanism.

A recess 18 is formed in the rear case 21, and a rod guide 19 supported in the recess 18 slidably supports the rear end portion of the rod 15, and the spring is pressed into the recess 18. The valve 20 fitted at the end is brought into contact with the rear end of the rod, and the valve seat provided at the rear end of the rod guide 19 is closed by pressing the valve 20. When the rod 15 is pushed in the backward direction, Press the valve to seat 1
9V is opened so that the air in the recess 18 escapes to the atmosphere.

A cylindrical ball case 23 is fitted in the rear case 21, a ball valve 24 is fitted in the ball case 23 under spring pressure, and the rear case 21 is inserted.
The ball case 23 is formed so as to connect the recess 18 formed in the inside and the ball case 23 to the air passage 22 that conducts the air.
A hole 23H is formed in the main body 1 and the switching valve 3 provided in the main body 1 is connected to the ball case 23.

As shown in detail in FIG. 1, FIG. 2 and FIG. 3, the switching valve 3 is provided in a cylindrical valve case 31.
The valve 32 is slidably fitted and the rear end of the valve 32 is pressed by a spring 33 fitted and inserted in the ball case 23 arranged so as to be joined to the rear end of the valve case 31. Further, two independent ring-shaped air passages 32a and 32b are provided on the outer periphery of the valve 32, and one air passage 32b is connected to a passage 32c opened to the rear end side of the valve 32.

Further, as shown in FIGS. 2 and 3, the tubular valve case 31 with one end closed is cross-sectioned along the longitudinal direction thereof, and when the cross-section position is shifted by 90 degrees, the outer circumference of the valve 32. Holes 31a, 31b and 31c, 31d, 31e connected to the air passages 32a, 32b provided on the surface
Is perforated. And the air motor rotates forward (clockwise)
At this time, as shown in FIG.
a and the air passage 32b are electrically connected to the large hole 31b, and at a position rotated by 90 degrees from this position, the air passage 32a and the small hole 31d are connected to the air passage 32b.
b is electrically connected to the large hole 31c. The valve 32 is pressed by the spring 33, and the valve tip is pressed against the inner end surface of the valve case 31.

When the set torque is generated in the main shaft 7 and the switching valve 3 is switched to the reverse rotation through the rod 15, the valve 32 moves to the left against the spring 33 as shown in FIGS. When moved, the air passage 32a is electrically connected to the hole 31a, but is closed to the small hole 31d, and the air passage 32b is closed to the large hole 31b and the large hole 31c.
The air is supplied to the air motor from the reverse rotation air passage and the reverse rotation is maintained.

Therefore, now the main valve 2 and the switching valve 3
Is operated to introduce pressurized air into the rotor chamber in the main body 1, the rotor 4 rotates clockwise at a high speed. The turning force of the rotor is transmitted to the liner 8 provided on the rotor shaft. The outer periphery of the liner 8 is rotatably supported by a cylindrical liner case 12, and the liner upper lid 1 is attached to both end faces of the case.
3. A liner lower lid 14 is provided to seal the hydraulic oil filled in the liner chamber. The rotation of the liner 8 changes the cross-sectional shape of the liner chamber.

At the time of striking, the seal surface 7a of the main shaft and the blade 9 are in contact with the seal surfaces 8a and 8b of the liner 8, respectively, and the liner chamber is divided into two chambers on the left and right with the blades 9 and 9 facing each other in a straight line. Moreover, the left and right chambers are further divided into a high pressure chamber H and a low pressure chamber L by the sealing surfaces 7a and 8a, and a high pressure chamber H and a low pressure chamber L are substantially formed on both sides of the blade. When the liner 8 is further rotated by the rotation of the rotor 4, the volume of the high pressure chamber H out of the two chambers separated by the seal surface 7a of the main shaft 7 and the seal surface 8a on the liner side immediately before the moment of impact. The volume of the low-pressure chamber L is reduced, and when the two chambers sandwiching the blades are completely sealed, a high pressure is generated in the high-pressure chamber. Then, the impact force is transmitted to the main shaft in which the blades are fitted, and a desired intermittent torque is generated in the main shaft to rotate the main shaft to perform the desired work.

When torque is generated in the main shaft by striking the blades and the liner is further rotated, the liner chamber is formed by the main blades and the sealing surface 8b sandwiching the above-mentioned blades. The chambers are electrically connected to each other to form one chamber, and the liner chamber is divided into two chambers having the same pressure. No torque is generated in the main shaft, and the liner is further rotated by the rotation of the rotor. The liner is 90 degrees, that is, 1 when hit
Sealing surfaces 8 of the liners facing each other when rotated by 80 degrees
b, 8b and the seal faces 7a, 7a of the main shaft are eccentric from the straight line passing through the center, respectively, so that both seal faces 7a, 7a
Since there is a gap between 8a and the liner chamber is divided into two chambers on the left and right by the main shaft and upper and lower blades 9 and 9, there is no pressure change in the entire liner chamber and the liner chamber has the same pressure. Turn to.

Further, the state in which the liner is rotated by 90 degrees and rotated by 270 degrees from the time of striking is substantially the same as the state in which the liner is rotated by 90 degrees, and the output adjusting valve position is merely upside down. When the liner further rotates from this state, the liner chamber is divided into two chambers on the left and right with the blade sandwiched between the blade and the liner side sealing surface 8b, and the main shaft / liner side sealing surfaces 7a and 8a. Come into contact with each other, and the liner chamber becomes four chambers, that is, two high pressure chambers and two low pressure chambers, and a pressure difference is generated between the two chambers across the blade, thereby generating a striking force as described above. One rotation of the lever liner produces a strong impact once.

The liner 8 is provided by the hydraulic impact torque generator 5.
When a high pressure is generated by the rotation of the
1, hydraulic fluid flows to the low pressure chamber L side through the relief valve B in the hole 10 and the port P2. At this time, until the pressure in the high pressure chamber H reaches a preset pressure, the relief valve B is pressed by the spring pressure against the end face of the relief valve shaft, and this pressure is not detected. However, when the pressure rises to the set pressure and a pulse is generated, the pressure on the high-pressure side H that has risen to the set pressure flows from the port P1 to the port P2. Is guided from the passage 11b through the cylinder 13d into the cylinder 13d, this pressure acts on the piston 16, pushes and moves the rod 15, operates the valve 20, and detects the set pressure.

The impact force is adjusted by the relief valve shaft 11
Is performed by adjusting the pressing force of the relief valve B, which is pressed by the spring, by rotating, and simultaneously closing the passages of P1 and P2.

By opening the main valve 2 until the main shaft 7 reaches the set torque, high-pressure air is supplied from the main air passage in the main body 1 to the rotor chamber through the passage for the right rotation of the switching valve, and as shown in FIG. As shown, a portion of the high pressure air is supplied to the left end closed chamber of the valve 32 through the orifice 31g of the valve case 31, and the right end chamber is also supplied with the air passage 32 from the hole 31b.
b, 32c. But at this time, valve 3
In FIG. 2, the pressure in the right side chamber is stronger than that in the left side due to the spring pressure added to the air pressure, the valve 32 is kept pressed to the left side inside the valve case 31, and the rotor continues to rotate to the right.

When the main shaft reaches the set torque and the rod 15 moves to the right as a result, the valve 20 is pushed to the right and the hollow 18 is connected to the atmosphere at the released valve 20, and the inside of the valve case 31 is closed. Thus, the pressure in the chamber on the right end side of the valve 32 is released to the atmosphere through the hole 23H and the air passage 22 through the recess 18. As a result, the inside of the valve on the left side inside the valve case becomes higher than the inside of the right side room, and the valve is moved to the valve case 3 by the air pressure as shown in FIGS.
Move in 1 to the right. As a result, the air passage supplied from the main valve 2 is supplied from the hole 31b to the air passage 32.
The exhaust gas is supplied to the rotor in the direction to rotate counterclockwise through a and 31a, and the exhaust gas is discharged to the atmosphere after passing through the hole 31c, the air passage 32b, and the hole 31e, whereby the rotor is automatically switched to counterclockwise rotation. . As long as the main valve is open, this switching valve is switched to the left rotation and the reverse rotation is maintained.

When the socket attached to the tip of the main shaft comes off from the stud bolt implanted, the reverse rotation of the rotor is stopped by closing the main valve, and at the same time, the switching valve 32 is restored by the pressing force of the spring 33, Switch to right rotation.

In this way, the rotor is rotated with the main valve opened, and when the main shaft reaches the set torque, it is automatically switched to the reverse rotation, and the switching valve is automatically restored by closing the main valve. To do.

[0027]

The pulse wrench for studs of the present invention detects that the main shaft has reached the set torque and supplies a part of the main air to switch the switching valve. Since it is automatically switched from the right rotation to the left rotation with the pulse wrench pressed while the switch is released, it has advantages such as easy operation and reliable operation.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a pulse wrench for a stud of the present invention.

FIG. 2 is a cross-sectional view of the switching valve when rotating to the right.

FIG. 3 is an explanatory diagram of the exhaust circuit.

FIG. 4 is a sectional view of a switching valve when switching to the left rotation.

FIG. 5 is an explanatory diagram of the exhaust circuit.

[Explanation of symbols]

 1 Main Body 2 Main Valve 3 Switching Valve 4 Rotor 5 Hydraulic Chamber Impact Torque Generator 7 Main Spindle 15 Rod 16 Piston 17 Cylinder 18 Recess 20 Valve 21 Rear Case 23 Ball Case 24 Valve 31 Valve Case 32 Valve

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[Procedure amendment]

[Submission date] February 26, 1993

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Fig. 6

[Correction method] Added

[Correction contents]

FIG. 6 is a vertical cross-sectional view of the hydraulic chamber striking torque generating device portion in FIG. 1.

[Procedure 3]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG.

[Fig. 2]

[Figure 3]

FIG. 4

[Figure 5]

FIG. 6

Claims (1)

[Claims] 1. A pulse wrench in which a main shaft is rotated by rotating a rotor through a hydraulic striking torque generating device, which penetrates the rotor shaft and detects a set pressure in the torque generating device. Is provided with a rod that operates in a manner such that the rear end of this rod abuts a valve supported by spring pressure, and
The switching valve provided in the pulse wrench and the chamber provided with the valve that is released by pressing the rod are brought into conduction, and air pressure is applied to both ends of the valve for forward / reverse switching provided in this switching valve to apply the air pressure to the main shaft. When the set torque is generated, the switching valve is switched via the rod valve, air is supplied in the reverse rotation direction of the rotor for reverse rotation, and this reverse rotation is maintained when the main valve is opened. Pulse wrench for studs.