JPH08197443A - Impact torque generating device for hydraulic torque wrench - Google Patents

Abstract

PURPOSE: To provide an impact torque generating device for a hydraulic torque wrench, with little sliding resistance so as to have fine energy efficiency and with little temperature rise of operating oil so as to obtain stable output while having durability. CONSTITUTION: An impact torque generating device for a hydraulic torque wrench is constituted of a liner 8 rotated by a rotor and having a cavity and the seal face inside, and a main shaft 9 disposed inside the liner 8 and having a blade 10 and the seal face. In this case, a magnet 12 for generating magnetic force for attracting the tip part of the blade 10 to the seal face is disposed at or near the seal face part of the liner 8 in which the tip part of the blade 10 comes in contact to seal the cavity in the liner 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a striking torque generator for a hydraulic torque wrench.

[0002]

2. Description of the Related Art As a striking torque generator for a torque wrench, a hydraulic torque wrench using a hydraulic striking torque generator with low noise and vibration has been developed and put into practical use. 7 and 8 show an example of this hydraulic torque wrench. The hydraulic torque wrench 1 is
It has a main valve 2 for supplying and stopping high-pressure air and a forward / reverse rotation switching valve 3 for selectively generating a forward / reverse rotation striking torque, and by the high-pressure air sent through the valves 2 and 3. A rotor 4 that generates a rotating torque is driven, and a hydraulic impact torque generator 5 that converts the rotational torque of the rotor 4 into an impact torque is provided in a case 6 of the hydraulic torque wrench 1. . The hydraulic striking torque generator 5 includes a liner 8 rotatably provided in a liner case 7, a cavity formed in the liner 8 filled with hydraulic oil, sealed, and coaxially inserted into the liner 8. 9 is provided with one or a plurality of blade insertion grooves, the blades 10 are inserted into the blade insertion grooves, and the blades 10 are constantly urged by the springs 11 in the outer peripheral direction of the main shaft 9 to form the inner peripheral surface 8a of the liner 8. The liner 8 is provided with an output adjusting mechanism 13 for adjusting the magnitude of the striking torque. When the liner 8 is rotationally driven by the rotor 4, when the plurality of seal surfaces formed on the inner peripheral surface of the liner 8 and the seal surface formed on the outer peripheral surface of the main shaft 9 and the blades 10 match, the main shaft 9 To generate a striking torque.

By the way, in the conventional striking torque generator for a hydraulic torque wrench, one or more blade insertion grooves are provided on the main shaft 9, and the blades 10 are inserted and inserted into the blade insertion grooves.
0 is always urged by the spring 11 in the outer peripheral direction of the main shaft 9 to contact the inner peripheral surface 8a of the liner 8, but
In this case, when the tip of the blade 10 comes into contact with the sealing surface formed on the inner peripheral surface of the liner 8, that is, the blade 10 projects most from the blade insertion groove, and the biasing force of the spring 11 is the weakest (calculation of a practical machine). (Value: 0.96 Kg), the blades 10 are spring 11 so that the cavity formed in the liner 8 is sealed.
It is necessary to urge the outer peripheral direction of the main shaft 9 at the maximum, but this urging force is maximum when the blade 10 that does not require sealing is housed in the blade insertion groove (calculated value for a practical machine: 2.59 Kg).
Therefore, the energy loss due to the sliding resistance between the tips 10a of the blades 10 and the inner peripheral surface 8a of the liner 8 is extremely large, and the frictional heat generated by this sliding causes the temperature of the hydraulic oil to rise and There is a problem that the output of the hydraulic torque wrench changes due to the change in viscosity. Further, in the case of the hitting torque generator of the conventional hydraulic torque wrench, as shown in FIG.
10a ′ of the liner 8 which is in sliding contact with the inner peripheral surface 8a is worn and the seal is incomplete, resulting in deterioration of performance, damage of the spring 11 that receives a large load repeatedly, and durability of the striking torque generator. There was also a problem with sex.

[0004]

SUMMARY OF THE INVENTION In view of the problems of the hitting torque generating device of the conventional hydraulic torque wrench, the present invention has a small sliding resistance, a high energy efficiency, and a small increase in the temperature of hydraulic oil and is stable. It is an object of the present invention to provide a striking torque generating device for a hydraulic torque wrench that can obtain the above output and that has durability.

[0005]

In order to achieve the above object, the present invention provides a liner which is rotated by a rotor and has a cavity and a sealing surface inside, and a liner which is disposed inside the liner and has a blade and a sealing surface. In a striking torque generating device for a hydraulic torque wrench consisting of a main shaft having, a tip of a blade is attached to or near a seal surface portion of a liner for contacting the tip of the blade to seal a cavity inside the liner. The gist is to dispose a magnet that generates a magnetic force to be attracted.

[0006]

In the striking torque generating device for the hydraulic torque wrench of the present invention, a magnet is arranged at or near the sealing surface of the liner that contacts the tip of the blade to seal the cavity inside the liner. By sucking the tip of the blade to the sealing surface and sealing the cavity inside the liner,
It is possible to omit a spring, which has been conventionally required, for urging the blade in the outer peripheral direction of the main shaft so as to contact the inner peripheral surface of the liner.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A striking torque generator for a hydraulic torque wrench according to the present invention will be described below with reference to the illustrated embodiments.

1 to 3 show a first embodiment of a striking torque generating device for a hydraulic torque wrench according to the present invention. The basic structure of the hydraulic torque wrench itself of this embodiment is the same as that of the conventional hydraulic torque wrench shown in FIG. 7, and the hydraulic torque wrench 1 includes a main valve 2 for supplying and stopping high pressure air and a positive valve. A rotor 4 having a forward / reverse rotation switching valve 3 for selectively generating a reverse rotation impact torque, and generating a rotation torque by high pressure air sent through the valves 2 and 3.
And a hydraulic impact torque generator 5 for converting the rotational torque of the rotor 4 into an impact torque is provided in the case 6 of the hydraulic torque wrench 1.

In the striking torque generating device 5, a liner 8 is rotatably provided in a liner case 7, a cavity formed in the liner 8 is filled with hydraulic oil, hermetically sealed, and a main shaft coaxially fitted in the liner 8. 9 is provided with two blade insertion grooves 91 communicating with each other at the center of the main shaft 9, and the blades 10 are fitted into the blade insertion grooves 91, and the liner 8 has an output adjusting mechanism for adjusting the magnitude of the impact torque. 13 is provided and configured.

Four sealing surfaces protruding in a mountain shape are formed on the inner peripheral surface of the cavity formed inside the liner 8 into which the main shaft 9 is fitted. Of these, the two sealing surfaces 81 that contact the tips of the blades 10 and seal the cavity formed inside the liner 8 are located at positions 180 ° rotationally symmetrical to each other, and
The other two sealing surfaces 82 contacting the sealing surface 92 formed on the inner surface of the liner 8 and sealing the cavity formed inside the liner 8 are the sealing surfaces 81 which are rotationally symmetrical with respect to each other. About the middle of each of the sealing surfaces 82
Are provided so that they are 180 ° rotationally asymmetric with respect to each other. Further, on both sides of a sealing surface 81 that contacts the tip of the blade 10 to the liner 8 and seals the cavity inside the liner 8,
The magnet 12 that generates a magnetic force that attracts the tip of the blade 10 is arranged on the sealing surface 81.

On the main shaft 9 coaxially arranged inside the liner 8, two blades 10 are fitted into the blade insertion grooves 91, and two sealing surfaces projecting in a mountain shape are formed on the peripheral surface. To do. At the position where the two blades 10 are 180 ° rotationally symmetrical to each other, the two sealing surfaces 92 are substantially in the middle of the two blades 10 whose rotational surfaces 82 are 180 ° rotationally symmetrical to each other. And each sealing surface 92 is 18
It is provided at a position where it becomes 0 ° rotationally asymmetric and at a position where it can contact the two sealing surfaces 82 formed on the liner 8 to seal the cavity formed inside the liner 8.

Next, the operating state of the impact torque generating device for the hydraulic torque wrench will be described.

First, when the high pressure air is introduced into the rotor chamber in the main body 1 by operating the main valve 2 and the switching valve 3, the rotor 4 rotates at a high speed. The rotational force of the rotor 4 is transmitted to the liner 8. By the rotation of the liner 8, the inside of the liner case 7 is changed to the one shown in FIG.
(D) → (a) ... changes.

In the state shown in FIG. 3A, the sealing surface 82 of the liner 8 and the tip of the blade 10 of the main shaft 9 are aligned (at this time, the blade 10 is not urged by the magnet 12 such as an attractive force). Since it does not work, sealing is not performed.)
Since the seal surface 81 of the liner 8 and the seal surface 92 of the main shaft 9 do not coincide with each other, the cavity inside the liner 8 is not divided into a high pressure chamber and a low pressure chamber, and a striking torque is not generated in the main shaft 9, so that the liner 8 Is further rotated by the rotation of the rotor 4.

When the liner rotates about 90 ° from this state, the magnet 1 disposed near the seal surface 81 of the liner 8
2, the tip of the blade 10 is sucked by the sealing surface 81, and the state shown in FIG. In this state, the seal surface 81 of the liner 8 and the tip of the blade 10 of the main shaft 9 are aligned with each other, and the seal surface 82 of the liner 8 and the seal surface 92 of the main shaft 9 are aligned with each other. Is a high pressure chamber H and a low pressure chamber L (however, the high pressure chamber H
The blades are communicated with each other via the blade insertion groove 91. ), Whereby a desired impact torque is generated on the main shaft 9.

After the impact torque is generated on the main shaft 9, the liner 8 is further rotated about 90 °, and the state shown in FIG. 3 (c) is obtained. In this state, the sealing surface 82 of the liner 8 is
Coincides with the tip of the blade 10 of the main shaft 9 (at this time, the blade 10 is not sealed because an urging force such as an attraction force by the magnet 12 does not act on the blade 10). Since the seal surface 92 of the main shaft 9 does not coincide with the seal surface 92 of the main shaft 9, the cavity inside the liner 8 is not divided into a high pressure chamber and a low pressure chamber, and the main shaft 9 does not generate a striking torque.
Is further rotated by the rotation of the rotor 4.

When the liner rotates about 90 ° from this state, the magnet 1 disposed near the sealing surface 81 of the liner 8
2, the tip of the blade 10 is sucked by the sealing surface 81, and the state shown in FIG. In this state, the sealing surface 81 of the liner 8 and the tip of the blade 10 of the main shaft 9 match, but the sealing surface 82 of the liner 8 and the sealing surface 92 of the main shaft 9 do not match, so that the cavity inside the liner 8 Is not divided into a high pressure chamber and a low pressure chamber, a striking torque is not generated in the main shaft 9, the liner 8 is further rotated by the rotation of the rotor 4, and returns to the state of generating a striking torque in FIG. This is repeated below.

As a result, an intermittent striking torque can be generated on the main shaft 9 once per one rotation of the liner.

When the rotor 4 is rotated in the reverse direction, the inside of the liner case 7 is shown in FIG. 3 (a) → (d) →
(C) → (b) → (a) ...
In addition, an intermittent striking torque can be generated once per revolution of the liner in the opposite direction.

FIG. 4 shows a second embodiment of a striking torque generating device for a hydraulic torque wrench according to the present invention. The following embodiments, including the third to fourth embodiments of the percussion torque generating device for the hydraulic torque wrench described below, have no difference in basic structure and operation from the above-described first embodiment of the present invention. Only the differences will be described below.

In the striking torque generating device 5 of this embodiment, the magnet 12 for generating a magnetic force for attracting the tip of the blade 10 to the seal surface 81 of the liner 8 is provided with the liner case 7 and the liner 8 on the outer peripheral side of the seal surface 81. It is arranged between.

The position where the magnet 12 is arranged is not limited to that of the first and second embodiments. For example, the magnet 12 is arranged so as to be embedded in the liner 8 on the outer peripheral side of the sealing surface 81. Alternatively, the sealing surface 81 itself may be made of a magnet.

FIG. 5 shows a third embodiment of a striking torque generating device for a hydraulic torque wrench according to the present invention. In the striking torque generating device 5 of the present embodiment, an auxiliary spring 14 for urging the blade 10 in the outer peripheral direction of the main shaft 9 is arranged in the blade insertion groove 91. This auxiliary spring 14 assists the sliding of the blade 10 fitted in the blade insertion groove 91, and is used to urge the conventional blade in the outer peripheral direction of the main shaft to contact the inner peripheral surface of the liner. By setting the spring constant and the length to be smaller than that of the provided spring, sliding of the blade 10, that is, a striking torque generating device without increasing the sliding resistance between the tip of the blade 10 and the inner peripheral surface of the liner 8. Can be surely performed.

FIG. 6 shows a fourth embodiment of a striking torque generating device for a hydraulic torque wrench according to the present invention. In the striking torque generating device 5 of the present embodiment, repulsive auxiliary magnets 15 are arranged at the base of the blade 10 fitted in the blade insertion groove 91 so as to urge the blade 10 in the outer peripheral direction of the main shaft 9. It is a thing.
The auxiliary magnet 15 assists the sliding of the blade 10 fitted in the blade insertion groove 91, and in order to urge the conventional blade in the outer peripheral direction of the main shaft to contact the inner peripheral surface of the liner. By setting the repulsive force smaller than the spring provided,
It is possible to surely perform the sliding of the blade 10, that is, the operation of the striking torque generating device, without increasing the sliding resistance between the tip of the blade 10 and the inner peripheral surface of the liner 8.

In each of the above embodiments, the liner 8-2 is used.
One sealing surface 82 and two sealing surfaces 92 of the main shaft 9,
By forming the respective sealing surfaces so as to be rotationally asymmetric with respect to each other by 180 °, the two sealing surfaces 82 of the liner 8 and the two main shafts 9 are provided only once per one rotation of the liner 8.
So that the individual sealing surfaces 92 coincide with each other, so that
Although an intermittent striking torque is generated on the main shaft 9 once per one rotation of the liner 8, the striking torque generating device of the hydraulic torque wrench of the present invention is not limited to that of this embodiment. First, the two sealing surfaces 82 of the liner 8
By forming the two sealing surfaces 92 of the main shaft 9 and the respective sealing surfaces so as to be rotationally symmetrical to each other by 180 °, the liner 8 is rotated twice per rotation of the liner 8.
The individual sealing surfaces 82 and the two sealing surfaces 92 of the main shaft 9 are made to coincide with each other, so that
It may be configured to generate an intermittent striking torque twice per rotation.

The number of sealing surfaces formed on the liner 8 and the number of blades arranged on the main shaft 9 and the number of sealing surfaces formed on the main shaft 9 are not limited to those in this embodiment. It is also possible to make the number of 1 or 3 or more.

[0027]

According to the striking torque generating device of the hydraulic torque wrench of the present invention, the blade which has been indispensable in the past is attracted by the magnet to attract the tip of the blade to the sealing surface to seal the cavity inside the liner. It is possible to omit the spring that urges the blade in the outer peripheral direction of the main shaft to contact the inner peripheral surface of the liner, and when the blade is housed in the blade insertion groove, the tip of the blade becomes maximum and the inner peripheral surface of the liner. The sliding resistance of the hydraulic torque wrench can be reduced, so that the sliding resistance is small, the energy efficiency is good, the temperature rise of the hydraulic oil is small, a stable output is obtained, and the durability is high. A torque generator can be obtained.

[Brief description of drawings]

FIG. 1 is an overall view of a hydraulic torque wrench incorporating a striking torque generator according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a striking torque generating device according to a first embodiment of the present invention.

FIG. 3 is a diagram showing an operating state of the striking torque generating device according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a striking torque generating device according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a striking torque generating device according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a striking torque generating device according to a fourth embodiment of the present invention.

FIG. 7 is an overall view of a hydraulic torque wrench incorporating a conventional striking torque generator.

FIG. 8 is a view showing a main part of a conventional striking torque generating device.

[Explanation of symbols]

 1 Main Body 2 Main Valve 3 Forward / Reverse Rotation Switching Valve 4 Rotor 5 Impact Torque Generator 7 Liner Case 8 Liner 81 Sealing Surface 82 Sealing Surface 9 Spindle 91 Blade Inserting Groove 92 Sealing Surface 10 Blade 12 Magnet 13 Output Adjusting Mechanism 14 Auxiliary Spring 15 Auxiliary magnet H High pressure chamber L Low pressure chamber

Claims (1)

[Claims] 1. A striking torque generating device for a hydraulic torque wrench comprising a liner that is rotated by a rotor and has a cavity and a sealing surface inside, and a main shaft that is disposed inside the liner and has a blade and a sealing surface. A magnet for generating a magnetic force for attracting the tip of the blade to the sealing surface is provided at or near the sealing surface of the liner that contacts the tip of the blade to seal the cavity inside the liner. A striking torque generator for a hydraulic torque wrench.