JPH07251382A - Hydraulic torque wrench - Google Patents

Abstract

PURPOSE:To provide a hydraulic torque wrench capable of generating one impact torque for each rotation of a liner while arranging two pieces of vanes on a spindle and capable of providing the stable and high stroke torque. CONSTITUTION:Two sealing surfaces 8b are formed in a straight line shape on a crossed line of the inner peripheral surface of a liner and a long axis of the liner, and another two sealing surfaces 8a are formed in the neighbourhood of a crossed line a2 of the inner peripheral surface of the liner and a short axis of the liner, symmetrical against a central line g2 in the longitudinal direction of a liner 8, in a bent shape in non-parallel with the crossed line a2 and so that the two sealing surfaces 8a rotate 180 deg. respectively and become nonsymmetrical.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic torque wrench having two blades, one for each rotation of the liner.
The present invention relates to a hydraulic torque wrench capable of generating a high impact torque by generating a single impact torque.

[0002]

2. Description of the Related Art As a torque wrench, a torque wrench is conventionally used that generates a striking torque by a mechanical method using a rotational force of a rotor and uses this to convert it into a desired torque. The method of obtaining the percussion torque by the method produces a loud percussion sound, which causes noise pollution.
There was a problem that vibration due to impact was large.

[0003]

For this reason, recently, a hydraulic torque wrench has been promisingly developed, which uses hydraulic pressure as a method for obtaining a striking torque to reduce noise and vibration. As a striking torque generator for a hydraulic torque wrench of this type, one having a single blade on the main shaft or a plurality of blades, for example, four blades as disclosed in Japanese Patent Publication No. 41-5800 are provided. In the former, in the rotatable liner with the main shaft inserted, that is, the hydraulic pressure of the striking torque generator becomes high, and a more precise and strong structure is required as a sealing method. There is a drawback that pressure acts only on one side of the main shaft, resulting in output loss, torque fluctuation, seizure, etc. due to the main shaft's deflection. In the latter, the impact torque is generated at least twice per one rotation of the liner. In addition, there are disadvantages that the inertia of the rotating mass of the case is small and the impact torque is low.

The present invention solves the problems of the conventional hydraulic torque wrench, so that the impact torque is generated once per one rotation of the liner while the main shaft is provided with two blades. An object of the present invention is to provide a hydraulic torque wrench that can obtain a stable high impact torque.

[0005]

In order to achieve the above object, a hydraulic torque wrench of the present invention forms a liner chamber having an eyebrow shape on a liner rotated by a rotor, and an inner peripheral surface of the liner is formed. Four sealing surfaces are provided, and two of these sealing surfaces are formed in a straight line shape on the line of intersection between the inner peripheral surface of the liner and the long axis of the liner, and the other two sealing surfaces are formed on the inner peripheral surface of the liner and the liner. Near the line of intersection with the minor axis, symmetrical with respect to the longitudinal centerline of the liner, in a bent shape not parallel to the line of intersection, and such that the two sealing faces are rotationally asymmetric by 180 ° with respect to each other. The main shaft has two blades slidably contacting two linear sealing surfaces when a striking torque is generated, and the outer peripheral surface of the spindle is formed into a bent shape when a striking torque is generated. Sliding contact with the two sealed surfaces 2 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]

The present invention will be described below with reference to the illustrated embodiments. In the figure, 1 is a main body of a hydraulic torque wrench, and a main valve 2 for supplying and stopping high-pressure air in the main body 2
A forward / reverse rotation switching valve 3 is provided, and a rotor 4 that generates a rotational torque by the high pressure air sent from this 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 striking torque is provided in a front case 6 projecting from the tip of the main body 1.

The hydraulic percussion torque generator 5 has a liner case 12 in which a liner 8 is rotatably fitted around a main shaft 7, and a hydraulic oil for generating a torque is filled and sealed in the liner 8. To do. In this case, the liner 8 is
The outer periphery of the liner case 12 is rotatably supported by a cylindrical liner case 12.
3. The liner lower lid 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 has a liner chamber having a cocoon-shaped cross section formed therein, and four sealing surfaces 8a and 8b are provided on the inner peripheral surface of the liner 8. .

As shown in FIG. 4, four sealing surfaces 8a,
Two of the sealing surfaces 8b of 8b are formed in a linear shape on the line of intersection 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 central axis of the liner chamber having an eyebrow shape). The two seal surfaces 8a are bent in the vicinity of the intersection line a2 between the inner peripheral surface of the liner and the minor axis of the liner, symmetrical with respect to the longitudinal centerline g2 of the liner 8 and non-parallel to the intersection line a2. For example, in this embodiment, the seal surface 8a is formed on two straight lines c2 and d2 having an angle β with respect to the line of intersection a2 to form a flat V-shape bent on the line of intersection a2, and The two sealing surfaces 8a are formed so as to be rotationally asymmetric with respect to each other by 180 °.

As shown in FIG. 2, the main shaft 7 has two blade insertion grooves 7 facing each other on a diameter line passing through the center of the main shaft.
b and 7b are provided, and the blades 9 slidingly contacting the two seal surfaces 8b linearly formed on the inner peripheral surface of the liner 8 when the impact torque is generated are inserted into the blade insertion grooves 7b. The blade 9 is always urged by the spring S in the outer peripheral direction of the main shaft. The blade 9 is formed to have a thickness smaller than the groove width of the blade insertion groove 7b.

On the outer peripheral surface of the main shaft 7 between the two blade insertion grooves 7b, when a striking torque is generated, two seal surfaces 7a which are slidably contact with two seal surfaces 8a formed in a curved shape on the inner peripheral surface of the liner 8. To form. This sealing surface 7a is shown in FIG.
As shown in, the intersection line a between the outer peripheral surface of the main shaft 7 and the straight line passing through the central axis of the main shaft 7 orthogonal to the straight line passing through the blade insertion groove 7b
In the vicinity of 1, a bent shape that is symmetrical with respect to the longitudinal centerline g1 of the main shaft 7 and is not parallel to the intersecting line a1, for example, in the present embodiment, two that have an angle β with respect to the intersecting line a1. By forming the sealing surface 7a on the straight lines c1 and d1 of the above, a flat V shape bent on the intersection line a1 is formed, and the two sealing surfaces 7a are rotationally asymmetric with respect to each other by 180 °.

In this way, the sealing surface 8a of the liner 8 is
8b, the blade 9 of the main shaft 7 and the seal surface 7a are respectively configured so that when the liner 8 rotates around the outer periphery of the main shaft 7, the seal surface 8a of the liner 8 is the seal surface 7a of the main shaft 7, Further, the sealing surface 8b of the liner 8 is in sliding contact with the blades 9 of the main shaft 7, respectively, and is hermetically sealed so that the liner chamber formed inside the liner 8 is divided into four.

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 sandwiched therebetween and the output adjusting valve insertion hole 10 are electrically connected, and the output adjusting valve 11 is provided in the output adjusting valve insertion hole 10. Is adjustable.

Next, the operation of the above hydraulic torque wrench will be described. When the main valve 2 and the switching valve 3 are operated to introduce high pressure air into the rotor 4 in the main body 1, the rotor 4 rotates at 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 of the liner 8 as shown in FIGS.

FIG. 2 (A) shows a state in which impact torque is generated on the main shaft 7, and the state in which the liner 8 is rotated by 90 degrees is shown in FIGS. 2 (B), (C) and (D). In FIG. 2 (A) when the impact torque is generated, the seal surface 7 a of the main shaft 7 is
And the blade 9 are in sliding contact with the seal surface 8a and the seal surface 8b of the liner 8, respectively, and the liner chambers face each other in a straight line.
It is divided into two left and right chambers with one blade 9 in between, and further, the left and right two chambers are divided into upper and lower high pressure chambers H and low pressure chambers L by a seal surface 7a and a seal surface 8a. Then, as the liner 8 rotates, the volume of the high-pressure chamber H decreases and the volume of the low-pressure chamber L increases. Due to the high pressure generated thereby, the side surface of the blade 9 is momentarily pressed to the low-pressure chamber L side, and the blade 9 A striking torque is generated on the main shaft 7 into which the main shaft 7 is inserted, and the main shaft 7 is rotated to perform a desired work. In this case, the sealing surfaces 7a, 8a
Is symmetrical with respect to the center lines g1 and g2 in the longitudinal direction, and the intersection line a
Since it is formed in a bent shape that is not parallel to 1 and a2, the seal surfaces 7a and 8a are sandwiched by the longitudinal center lines g1 and g2.
It is possible to balance the pressure applied to the shaft and obtain a stable striking torque. Two high pressure chambers H
Are communicated with each other through the blade insertion groove 7b, but the volumes of the two high pressure chambers H can be configured to be the same depending on the shapes of the seal surface 7a and the seal surface 8a. It is possible to eliminate the flow of hydraulic oil between the two, and even when the cycle of generating the impact torque is short, there is no difference in the pressure generated between the two high pressure chambers H, and a stable impact torque can be obtained. In this case, the striking torque can be adjusted by the output adjusting valve 11 in the same manner as in the conventional case.

When the liner 8 further rotates 90 degrees after the impact torque is generated on the main shaft 7, as shown in FIG. 2 (B), the liner chamber is electrically connected to both the high pressure and low pressure chambers.
It is divided into two chambers of the same pressure, and no impact torque is generated on the main shaft 7, and the liner 8 rotates further.

Further, when the liner 8 is rotated by 90 degrees, that is, 180 degrees from when the striking torque is generated, it becomes as shown in FIG. 2 (C). In this state, the two seal surfaces 8a of the liner 8 and the two seal surfaces 7a of the main shaft 7 are formed so as to be rotationally asymmetric with respect to each other by 180 °, so that the seal surface 8a of the liner 8 and the seal of the main shaft are sealed. Face 7
Since a does not coincide with a and a gap is created between the two, the liner chamber is divided into two chambers of the same pressure by the blades 9, the striking torque is not generated in the main shaft 7, and the liner 8 further rotates. In this case, the two seal faces 7a of the main shaft 7 and the two seal faces 7a of the liner 8
Even if the two seal surfaces 8a are close to each other, the seal surfaces 7a and 8a are formed in a bent shape that is symmetrical with respect to the longitudinal centerline g1 of the main shaft 7 and is not parallel to the intersection line a1. Therefore, compared with the case where the sealing surface is formed in a linear shape, the working oil flows more smoothly in the liner chamber, which reduces the rotational resistance of the liner 8 other than when a striking torque is generated, and a stable operating state. Can be obtained.

Further, when the liner 8 is rotated by 90 degrees, that is, 270 degrees from when the striking torque is generated, it becomes as shown in FIG. 2 (D). 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, and is divided into two chambers of the same pressure. No impact torque is generated and the liner 8 rotates further.

Further, when the liner 8 rotates 90 degrees, that is, 360 degrees from the time when the striking torque is generated, the state shown in FIG. 2 (A) is obtained, and the striking torque is generated on the main shaft 7 in which the blade 9 is inserted and inserted. In this way, one revolution of the liner 8
It is possible to generate a percussion 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 a striking torque once per one rotation of the liner.
Since the sealing surface is formed in a bent shape that is symmetrical with respect to the center line in the longitudinal direction and is not parallel to the intersecting line, it is possible to balance it by sandwiching the center line in the longitudinal direction.
Compared to the case where the sealing surface is formed in a straight line shape, the working oil is circulated smoothly in the liner chamber, thereby reducing the rotational resistance of the liner except when the striking torque is generated, and obtaining a stable high striking torque. be able to.

[Brief description of 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 operating state of a hydraulic impact torque generating device.

FIG. 3 is a development view of a spindle.

FIG. 4 is a development view of a liner.

[Explanation of symbols]

 1 Main Body 2 Main Valve 3 Forward / Reverse Rotation Switching Valve 4 Rotor 5 Hydraulic Impact Torque Generator 7 Spindle 7a Sealing Surface 8 Liner 8a Sealing Surface 8b Sealing 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)

[Claims] 1. A liner chamber having an eyebrow shape is formed in a liner (8) rotated by a rotor (4), and four sealing surfaces (8a, 8b) are provided on an inner peripheral surface of the liner (8). , Two of these sealing surfaces (8b) are formed in a linear shape on the line of intersection between the inner peripheral surface of the liner and the long axis of the liner,
The other two sealing surfaces (8a) are arranged in the vicinity of the intersection (a2) between the inner peripheral surface of the liner and the minor axis of the liner, symmetrical with respect to the longitudinal centerline (g2) of the liner (8), It is formed in a bent shape that is not parallel to the intersection line (a2), and the two sealing surfaces (8a) are rotationally asymmetric with respect to each other by 180 °, and the main shaft (7) has a linear shape when a striking torque is generated. The two blades (7) slidably contacting the two sealing surfaces (8b) formed on the outer peripheral surface of the main shaft (7) are formed into a bent shape when a striking torque is generated. A hydraulic torque wrench, characterized in that two sealing surfaces (7a) that are in sliding contact with (8a) are formed so that a striking torque is generated once per one rotation of the liner (8).