JP2630574B2 - Hydraulic torque wrench - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a hydraulic torque wrench having two blades.
The present invention relates to a hydraulic torque wrench capable of generating a constant impact torque so as to obtain a stable and high impact torque.

[0002]

2. Description of the Related Art Conventionally, a torque wrench has been used in which a striking torque is generated by a mechanical method using the rotational force of a rotor and is converted into a desired torque by using the torque. In the method of obtaining the impact torque by the method, the impact sound is loud, causing noise pollution,
There was a problem that vibration due to impact was large.

[0003]

For this reason, a hydraulic torque wrench that uses hydraulic pressure as a method for obtaining a percussive torque and reduces noise and vibration has recently been seen as promising and has been developed. As a striking torque generating device for a hydraulic torque wrench of this type, a device provided with one blade on a main shaft or a plurality of blades, for example, four blades as disclosed in Japanese Patent Publication No. 41-5800. However, in the former, the hydraulic pressure in the rotatable liner in which the main shaft is inserted, that is, the impact torque generator increases, and a more precise and strong structure is required as a sealing method. Pressure acts on only one side of the liner, resulting in a loss of output, a variation in torque, seizure, etc., due to the direction of the main shaft. In the latter, the impact torque is generated at least twice per rotation of the liner. In addition, there is a disadvantage that the inertia of the rotating mass of the case is small and the impact torque is low.

[0004] The present invention solves the problems of the conventional hydraulic torque wrench, and generates one impact torque per rotation of the liner while arranging two blades on the spindle. It is another object of the present invention to provide a hydraulic torque wrench capable of obtaining a stable and high impact torque.

[0005]

In order to achieve the above object, a hydraulic torque wrench of the present invention has a liner chamber shaped like a eyebrow formed on a liner rotated by a rotor, and has an inner peripheral surface of the liner. Four sealing surfaces are provided, two of which are formed in a straight line on the intersection of the inner peripheral surface of the liner and the long axis of the liner, and the other two sealing surfaces are formed of the inner peripheral surface of the liner and the liner. In the vicinity of the line of intersection with the short axis, symmetrical with respect to the longitudinal center line of the liner, in a bent shape that is non-parallel to the line of intersection, and such that the two sealing surfaces are 180 ° rotationally asymmetric with respect to each other. When the impact torque is generated, two blades that slide in contact with the two sealing surfaces formed in a linear shape are arranged on the main shaft, and the main shaft is formed into a bent shape when the impact torque is generated on the outer peripheral surface of the main shaft. 2 which comes into sliding contact with the two sealing surfaces The sealing surface is formed of, thereby summarized in that which is adapted to generate a single impact torque per revolution of the liner.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS 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, and a main valve 2 for supplying and stopping high-pressure air into the main body.
And a forward / reverse switching valve 3, and a rotor 4 for generating a rotating torque by high-pressure air supplied from the valve group is provided in the main body 1.

A hydraulic striking torque generator 5 for converting the rotational torque of the rotor 4 into a striking torque is provided in a front case 6 projecting from the tip of the main body 1.

The hydraulic impact torque generator 5 has a liner 8 rotatably fitted to a main shaft 7 inside a liner case 12, and the liner 8 is filled with a working oil for generating torque and sealed. I do. In this case, the liner 8
The outer periphery of the liner case 12 is rotatably supported by a cylindrical liner case 12.
3. A liner lower cover 14 is provided so that the hydraulic oil filled in the liner 8 is sealed.

As shown in FIG. 2, the liner 8 into which the main shaft 7 is inserted forms a liner chamber having a cocoon-shaped cross section, and four seal surfaces 8a and 8b are provided on the inner peripheral surface of the liner 8. .

As shown in FIG. 4, four sealing surfaces 8a,
8b, two sealing surfaces 8b are formed in a linear shape on the intersection line between the inner peripheral surface of the liner and the long axis of the liner (the straight line in the major axis direction passing through the center axis of the liner chamber having a cocoon shape). The two sealing surfaces 8a are bent near the intersection line a2 between the inner peripheral surface of the liner and the short axis of the liner, symmetric with respect to the longitudinal center line g2 of the liner 8, and non-parallel to the intersection line a2; For example, in this embodiment, by forming the sealing surface 8a on two straight lines c2 and d2 having an angle β with respect to the intersection line a2, a flat V-shape bent on the intersection line a2, and The two seal surfaces 8a are formed so as to be rotationally asymmetrical by 180 ° with respect to each other.

As shown in FIG. 2, two blade insertion grooves 7 are formed in the main shaft 7 so as to face each other on a diameter line passing through the center of the main shaft.
b, 7b, into each blade insertion groove 7b, when impact torque is generated, a blade 9 that slides on two linearly formed sealing surfaces 8b on the inner peripheral surface of the liner 8 is fitted and inserted. The blade 9 is always urged in the outer peripheral direction of the main shaft by the spring S. The thickness of the blade 9 is smaller than the width of the blade insertion groove 7b.

Two sealing surfaces 7a slidingly contacting two sealing surfaces 8a formed in a bent shape on the inner peripheral surface of the liner 8 when an impact torque is generated on the outer peripheral surface of the main shaft 7 between the two blade insertion grooves 7b. To form This sealing surface 7a is
As shown in FIG. 5, an intersection line a between the outer peripheral surface of the main shaft 7 and a straight line passing through the central axis of the main shaft 7 which is orthogonal to a straight line passing through the blade insertion groove 7b.
In the vicinity of 1, a bent shape symmetrical with respect to the center line g1 in the longitudinal direction of the main shaft 7 and non-parallel to the intersection line a1, for example, in this embodiment, two lines having an angle β with respect to the intersection line a1 Are formed on the straight lines c1 and d1 in a flat V-shape bent on the intersection line a1 so that the two seal surfaces 7a are rotationally asymmetric with respect to each other by 180 °.

As described above, the sealing surfaces 8a, 8a,
8b and the blades 9 and the sealing surface 7a of the main shaft 7 are respectively configured so that when the liner 8 rotates around the outer periphery of the main shaft 7, the sealing surface 8a of the liner 8 becomes the same as the sealing surface 7a of the main shaft 7, In addition, the sealing surface 8b of the liner 8 is in sliding contact with the blade 9 of the main shaft 7 so that the liner chamber formed inside the liner 8 is air-tightly sealed so as to divide the liner chamber into four parts.

An output adjusting valve insertion hole 10 is formed in the vicinity of one sealing surface 8b of the liner 8 in parallel with the central axis of the liner 8, and the output adjusting valve insertion hole 10 is formed.
The ports P1 and P2 are formed so that the liner chamber formed inside the liner 8 with the sealing surface 8b interposed therebetween and the output adjustment valve insertion hole 10, and the output adjustment valve 11 is provided in the output adjustment valve insertion hole 10. Is adjustably inserted.

Next, the operation of the hydraulic torque wrench will be described. When the high pressure air is introduced into the rotor 4 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 rotation of the rotor 4 is transmitted to the liner 8 connected to the rotor shaft, and the rotation of the liner 8 changes the cross-sectional shape inside the liner 8 as shown in FIGS.

FIG. 2A shows a state in which a striking torque is generated on the main shaft 7, and FIGS. 2B, 2C and 2D show a state in which the liner 8 is rotated by 90 degrees. In FIG. 2A when the impact torque is generated, the sealing surface 7a of the main shaft 7 is formed.
And the blades 9 are in sliding contact with the sealing surfaces 8a and 8b of the liner 8, respectively.
Each of the two blades 9 is divided into two chambers on the left and right sides. Further, the two chambers on the left and right sides are divided into a high-pressure chamber H and a low-pressure chamber L at the upper and lower sides by a sealing surface 7a and a sealing surface 8a. By the rotation of the liner 8, the volume of the high-pressure chamber H decreases and the volume of the low-pressure chamber L increases. The high pressure generated thereby momentarily presses the side surface of the blade 9 toward the low-pressure chamber L, and the blade 9 Is applied to the main shaft 7 to rotate the main shaft 7 to perform a desired operation. In this case, the sealing surfaces 7a, 8a
Is symmetrical with respect to the longitudinal center lines g1 and g2, and the intersection line a
Since it is formed in a bent shape that is non-parallel to 1 and a2, the sealing surfaces 7a and 8a sandwich the longitudinal center lines g1 and g2.
Can be balanced, and a stable impact torque can be obtained. The two high pressure chambers H
Are communicated via the blade insertion groove 7b, but the volumes of the two high-pressure chambers H can be the same depending on the shapes of the sealing surfaces 7a and 8a. The hydraulic oil flow between the two high-pressure chambers H can be eliminated, and a stable impact torque can be obtained even when the impact torque generation cycle is short. In this case, the adjustment of the impact torque can be performed by the output adjusting valve 11 in the same manner as in the related art.

After the impact torque is generated on the main shaft 7, when the liner 8 is further rotated by 90 degrees, as shown in FIG.
The chamber is divided into two chambers having the same pressure, and no impact torque is generated on the main shaft 7, and the liner 8 further rotates.

Further, when the liner 8 is rotated by 90 degrees, that is, by 180 degrees from the time when the impact torque is generated, the state shown in FIG. 2C is obtained. In this state, the two sealing surfaces 8a of the liner 8 and the two sealing surfaces 7a of the main shaft 7 are formed so as to be 180 ° rotationally asymmetric with respect to each other. Face 7
a does not coincide with each other, there is a gap between the two, and the liner chamber is divided into two chambers of the same pressure by the blades 9, no impact torque is generated on the main shaft 7, and the liner 8 further rotates. In this case, two sealing surfaces 7a of the main shaft 7 and two
Even when the two sealing surfaces 8a are close to each other, the sealing surfaces 7a and 8a are formed in a bent shape that is symmetric with respect to the center line g1 in the longitudinal direction of the main shaft 7 and is not parallel to the intersection line a1. Therefore, as compared with the case where the sealing surface is formed in a linear shape, the flow of the hydraulic oil in the liner chamber becomes smoother, whereby the rotational resistance of the liner 8 other than when the impact torque is generated is reduced, and the operating state is stabilized. Can be obtained.

Further, when the liner 8 rotates 90 degrees, that is, 270 degrees from the time when the impact torque is generated, the liner 8 becomes as shown in FIG. This state is substantially the same as the state rotated by 90 degrees shown in FIG. 2 (B), and the liner chamber is divided into two chambers of high pressure and low pressure that are electrically connected to each other, and divided into two chambers of the same pressure. No impact torque is generated, and the liner 8 further rotates.

Further, when the liner 8 rotates 90 degrees, that is, 360 degrees from the time when the impact torque is generated, the state shown in FIG. 2A is reached, and the impact torque is generated on the main shaft 7 into which the blade 9 is inserted. In this way, one rotation per rotation of the liner 8
It is possible to generate a single impact torque.

[0021]

According to the hydraulic torque wrench of the present invention,
While arranging two blades on the main shaft, it is possible to generate one impact torque per rotation of the liner,
Since the sealing surface is symmetrical with respect to the longitudinal center line and is formed in a bent shape that is non-parallel to the intersection line, it can be balanced across the longitudinal center line,
Compared to the case where the sealing surface is formed in a linear shape, the flow of the hydraulic oil in the liner chamber is smoothed, thereby reducing the rotational resistance of the liner except when the impact torque is generated, and obtaining a stable and high impact torque. be able to.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a hydraulic torque wrench of the present invention.

FIG. 2 is an explanatory diagram showing an operation state of a hydraulic impact torque generating device.

FIG. 3 is a development view of a main shaft.

FIG. 4 is a development view of a liner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Main valve 3 Forward / reverse rotation switching valve 4 Rotor 5 Hydraulic impact torque generator 7 Main shaft 7a Seal surface 8 Liner 8a Seal surface 8b Seal surface 9 Blade 10 Output adjustment valve insertion hole 11 Output adjustment valve 12 Liner case 13 Liner Upper lid 14 Liner lower lid H High pressure chamber L Low pressure chamber P1 port P2 port

Claims (1)

(57) [Claims] A liner (8) rotated by a rotor (4) is formed with a liner chamber in the form of a cocoon, and four liner surfaces (8a, 8b) are provided on the inner peripheral surface of the liner (8). Two of the sealing surfaces (8b) are formed in a straight line on the intersection between the inner peripheral surface of the liner and the long axis of the liner,
The other two sealing surfaces (8a) are symmetric with respect to the longitudinal center line (g2) of the liner (8) near the intersection (a2) between the inner peripheral surface of the liner and the short axis of the liner, The two sealing surfaces (8a) are formed in a bent shape that is non-parallel to the intersection line (a2) so that the two sealing surfaces (8a) are rotationally asymmetric with respect to each other by 180 °. And two blades (7) slidingly in contact with the two sealing surfaces (8b) formed on the outer surface of the main shaft (7). (8a) A hydraulic torque wrench characterized by forming two sealing surfaces (7a) which are in sliding contact with each other to generate one impact torque per rotation of the liner (8).