JP2779749B2 - Impact torque generator for hydraulic torque wrench - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention is intended to obtain a stable high torque without increasing the oil pressure in a hydraulic impact torque generator by generating one impact per rotation of a liner by using three or more blades. The present invention relates to a hydraulic torque wrench.

[0002]

2. Description of the Related Art In a torque wrench of a pneumatic tool, a striking force is generated by a mechanical method by the rotational force of a rotor, and the torque is converted into a desired torque by using the striking force. Therefore, in the method of obtaining the impact torque by this mechanical method, the impact sound is loud, causing noise pollution, and the vibration due to the impact is also large.

[0003] Therefore, recently, a torque wrench of a type that uses oil pressure as a method for obtaining a percussive torque and that prevents noise and vibration has been considered promising and has been developed. By the way, as a hydraulic impact torque generating device, there is a device provided with one blade on a main shaft or a plurality of devices, for example, a device provided with four blades as disclosed in Japanese Patent Publication No. 41-5800. In the former case, ,
If a high torque is to be obtained, the hydraulic pressure of the impact torque generating device is increased in the rotatable liner in which the main shaft is inserted, and the sealing mechanism becomes more precise and strong, and the blades are biased in the main shaft inner circumferential direction. Pressure, which causes the spindle to be offset, causing loss of output, torque variation,
There is a disadvantage of causing seizure and the like. In the latter case, since at least two hits are generated per one rotation of the liner, the inertia of the rotational mass of the liner and the case is small, and the hitting torque is low.

In order to solve these problems, the applicant of the present application first provided two blades on the main shaft and sealed the seal surface of the liner, the seal surface of the main shaft and the blade only once per rotation of the liner. A hydraulic torque wrench that generates a single impact torque has been proposed (see Japanese Utility Model Publication No. 1-201212). However, in order to improve the working efficiency, there has been a demand for a device capable of obtaining an impact torque larger than that obtained by this device without increasing the size of the device.

[0005]

SUMMARY OF THE INVENTION In view of the foregoing, the present invention provides a hydraulic torque wrench capable of obtaining a high impact torque while reducing noise and vibration without increasing the size of the device. It is an object to provide a torque generating device.

[0006]

In order to achieve the above object, the present invention provides a hydraulic torque wrench having an impact torque generating device which is rotated by a rotor and has a liner having a cavity and a sealing surface therein, In a striking torque generating device for a hydraulic torque wrench comprising a blade and a main shaft having a sealing surface, the liner has six or more 2n sealing surfaces, and the liner has a plurality of 2n sealing surfaces. Of which n
The seal surfaces are located at positions where each seal surface is rotationally symmetric with respect to each other at 360 / n degrees, and the other n seal surfaces are rotationally symmetric with respect to each other at the n seal surfaces with respect to each other. It is approximately halfway between the sealing surfaces, and each sealing surface is 360 /
The main shaft is disposed at a position that is rotationally asymmetrical by n degrees,
Blades and n sealing surfaces, wherein the n blades are:
Each of the blades is inserted into a blade insertion groove provided at a position where the blades are rotationally symmetric with respect to each other at 360 / n degrees, and the n sealing surfaces are substantially in the middle of the n blades. When the respective seal surfaces are mutually rotationally asymmetrical by 360 / n degrees, and the n rotationally symmetrical seal surfaces of the liner and n blades of the main shaft coincide with each other per rotation of the liner. 360 n of said liners
/ N degrees of rotation asymmetrical sealing surface and at the same time as the same position, and the blade insertion groove provided on the main shaft is formed of a bottomed groove that does not communicate with each other. Two sets of communication holes communicating with every other cavity inside the liner defined by the blades and the sealing surface of the main shaft are provided between the blade insertion groove and the sealing surface of the main shaft so as not to communicate with the blade insertion groove. It is characterized by being drilled.

[0007]

According to the striking torque generator of the hydraulic torque wrench of the present invention, the n number of mutually 360 / n-degree rotationally symmetric sealing surfaces and the n number of blades of the main shaft are provided once per rotation of the liner. At the same time, the n mutually 360 / n-degree rotationally asymmetric sealing surfaces of the liner and the n mutually 360 / n-degree rotationally asymmetrical sealing surfaces of the main shaft coincide with each other. Occur. In this case,
Since three or more n blades are fitted to the main shaft so as to be able to come and go in the blade insertion grooves, a large pressure receiving surface can be obtained, and a high impact torque can be obtained. In addition, while reducing the strength of the main shaft by reducing the number of blade insertion grooves provided in the main shaft to three or more, two or more communication holes formed in the main shaft allow three or more blades to be inserted at any time in both forward and reverse rotations. The high pressure chambers can communicate with each other.

[0008]

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. 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 impact torque are provided in the body 1. And a rotor 4 for generating a rotational torque by high-pressure air supplied from the valve group. A hydraulic impact torque generating device 5 for converting the rotational torque of the rotor 4 into an impact torque is provided in a front case 6 protruding from the tip of the main body 1.

The hydraulic striking torque generating device 5 has a liner 8 rotatably fitted to a main shaft 7 inside a liner case 12 and fills and seals a hydraulic oil for generating a torque in the liner 8. And the spindle 7 has 120
The three blade insertion grooves 15 are provided at positions that are rotationally symmetrical in degrees,
Three blades 9 are inserted into each groove 15 and the three blades 9 are constantly urged in the outer peripheral direction of the main shaft by a spring S. In addition, the thickness of the blade 9 is determined by the groove width of the blade insertion groove 15. The three sealing surfaces 7 slightly projecting from the outer peripheral surface of the main shaft are provided on the outer peripheral surface of the main shaft between the three blades 9.
a is formed. The three sealing surfaces 7a are provided at positions where the respective sealing surfaces 7a are substantially at the center of the blade insertion groove 15 and the respective sealing surfaces 7a are rotationally asymmetric with each other by 120 degrees.

The liner 8 into which the main shaft 7 is inserted has a cavity formed therein, and is formed on the inner peripheral surface thereof so as to protrude in a mountain shape to form six sealing surfaces. Of these, three sealing surfaces 8b are At a position where each seal surface 8b is rotationally symmetric with each other by 120 degrees,
The other three sealing surfaces 8a are substantially intermediate between the three sealing surfaces 8a that are rotationally symmetric with each other and the sealing surfaces 8a are rotationally asymmetric with each other by 120 degrees. Position.

The three blades 9 of the main shaft 7 and the three sealing surfaces 9a and the six sealing surfaces 8a and 8b of the liner 8 are provided.
When three blades 9 of the main shaft 7 and three mutually rotationally symmetrical sealing surfaces 8b of the liner 8 are aligned with each other for one rotation of the liner, the three rotations of the main shaft 7 are mutually rotated by 120 degrees. The three mutually asymmetrical sealing surfaces 7a and liner 8
It is provided so that the sealing surface 8a, which is asymmetrical by 20 degrees, coincides once at the same time.

FIGS. 5 to 9 show specific examples of the arrangement of the three blades 9 of the main shaft 7 and the three sealing surfaces 9a and the six sealing surfaces 8a and 8b of the liner 8. (A) shows the main shaft 7,
(B) is a development view of the liner 8.
As shown in each figure, the three blades 9 of the main shaft 7 and the three seal surfaces 8b of the liner 8 that are rotationally symmetric with each other by 120 degrees are
All of them are linear and arranged at equal intervals of 120 degrees, and the three seal faces 7a of the main shaft 7 which are rotationally asymmetric with respect to each other by 120 degrees.
And the three mutually 120-degree rotationally asymmetrical sealing surfaces 8a of the liner 8 are located substantially in the middle of the three mutually rotationally symmetrical sealing surfaces 8b of the main shaft 7 or the three blades 9 of the liner 8. Each of them has a linear shape, and two of the three sealing surfaces 7a and 8a are arranged so as to be shifted back and forth from a line at equal intervals of 120 degrees (FIG. 5).
The two sealing surfaces 7a, 8a are formed in a crank shape facing each other (FIG. 6), or two out of three sealing surfaces 7a, 8a are formed.
8a may be a crank shape having a different shape (FIG. 7);
Two of the three sealing surfaces 7a, 8a may be formed into inclined line shapes (FIG. 8), or two of the three sealing surfaces 7a, 8a.
Can be formed into a V-shape facing each other (FIG. 9), but is not limited thereto, and as described above, three rotations of the main shaft 7 and the three liners 8 of the liner 8 per one rotation of the liner. When the 120 ° rotationally symmetrical sealing surfaces 8b coincide with each other, the three mutually 120 ° rotationally asymmetrical sealing surfaces 7a of the main shaft 7 and the three mutually 120 ° rotationally asymmetrical sealing surfaces 8a of the liner 8 are simultaneously formed. Any one that matches once may be used.

Two sets of communicating holes 16a and 16b are provided for communicating with every other cavity inside the liner 8 defined by the blades 9 and the sealing surface 7a of the main shaft 7 and the sealing surfaces 8a and 8b of the liner 8. 7 is provided between the blade insertion groove 15 and the sealing surface 7a.

In the inside of the liner 8, an output adjustment valve insertion hole 10 is formed in parallel with the axis of the liner 8, and the output adjustment valve insertion hole 10 has a sealing surface 8a (or a sealing surface 8).
b) Ports P1 and P2 are formed so that the cavity inside the liner 8 divided by the sealing surface 7a (or the blade 9) of the main shaft 7 across the main shaft 7 and the power adjustment valve insertion hole 10 are connected to each other, and the holes P1 and P2 are formed in the holes. The output adjustment valve 11 is fitted in an adjustable manner.

The liner 8 is rotatably supported on its outer periphery by a cylindrical liner case 12.
A liner upper lid 13 and a liner lower lid 14 are provided on both end surfaces of the liner 8, and the liner upper lid 13 is further fixed with a liner case lid 18 to seal the working oil filled in the liner 8. Injection and discharge of the hydraulic oil are performed by opening an oil cover 17 provided on the liner lower cover 14.

In the above embodiment, the main shaft 7 is provided with three blades 9 and three sealing surfaces 9a, and the liner 8 is provided with six sealing surfaces 8a and 8b. The number of surfaces is not limited to this, and four or more blades and four
By providing at least eight sealing surfaces on the liner 8 in accordance with the above-described embodiment, eight or more sealing surfaces 8a and 8b can provide a wider pressure receiving surface.

Next, the operating state of the above-described hydraulic torque wrench impact torque generating device 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 this rotor is transmitted to the liner 8.

As the liner 8 rotates, the inside of the liner 8 changes as shown in FIG. 4 (a) → (b) → (c) → (a). FIG. 4A shows a state in which a pulse, that is, an impact torque is generated on the main shaft 7.
(B) and (c) show a state where is rotated by 120 degrees.

At the time of impact, as shown in FIG.
Of the liner 8 are in contact with the sealing surfaces 7a and 8b of the liner 8, respectively, and the cavity inside the liner 8 is divided into six chambers, each of which alternately has a high-pressure chamber H and a low-pressure chamber L.
become. When the liner 8 is rotated by the rotation of the rotor 4, the volume of the high-pressure chamber H is reduced and the volume of the low-pressure chamber L is increased immediately before the moment of the impact, and the two chambers sandwiching the blade 9 are completely sealed. When the pressure becomes high, a high pressure is generated in the high-pressure chamber, and the side surface of the blade 9 is momentarily pressed toward the low-pressure chamber with the hydraulic pressure, and the striking force is transmitted to the main shaft 7 into which the blade 9 is inserted, and A desired intermittent impact torque is generated to rotate the main shaft 7 to perform a desired operation.

After the impact torque is generated on the main shaft, when the liner 8 further rotates by 120 degrees, the blade 9 of the main shaft 7 and the sealing surface 8b of the liner 8 are aligned as shown in FIG. Since the sealing surface 7a of the liner 8 does not match with the sealing surface 8a of the liner 8, the cavity inside the liner 8 is not divided into a high-pressure chamber and a low-pressure chamber, and becomes three chambers as a whole.
No impact torque is generated on the main shaft 7, and the liner 8 is further rotated by the rotation of the rotor 4. In this manner, the liner is further extended by 120 degrees, that is, two times more than when the impact torque is generated.
When rotated by 40 degrees, it becomes as shown in FIG. In this state as well, as in FIG. 4B, the blade 9 of the main shaft 7 and the sealing surface 8b of the liner 8 match, but the sealing surface 7a of the main shaft 7 does not match the sealing surface 8a of the liner 8. The cavity inside the liner 8 is not divided into a high-pressure chamber and a low-pressure chamber, and has three chambers as a whole. No impact torque is generated on the main shaft 7, and the liner 8 is further rotated by the rotation of the rotor 4, and FIG. The procedure returns to the state in which the impact torque of a) is generated, and this is repeated thereafter.

In this manner, a strong impact torque can be generated once by one rotation of the liner. The adjustment of the striking force is performed by the output adjusting valve 11 in the same manner as in the prior art.

[0022]

According to the striking torque generating device for a hydraulic torque wrench of the present invention, the blade insertion groove provided on the main shaft is constituted by a bottomed groove which does not communicate with each other, and the seal surface of the liner and the main shaft blade are formed. And two sets of communication holes that communicate with each other every other cavity inside the liner defined by the sealing surface between the blade insertion groove of the main shaft and the sealing surface so as not to communicate with the blade insertion groove. Thus, it is possible to obtain a striking torque generating device capable of selectively generating a high striking torque with forward and reverse rotations without increasing the size of the device and without increasing noise and vibration. A decrease in the strength of the main shaft caused by providing three or more blade insertion grooves is reduced by configuring the blade insertion grooves with bottomed grooves that do not communicate with each other, thereby improving the durability of the device.
Three or more high-pressure chambers can communicate with each other during both forward and reverse rotations by two sets of communication holes formed in the main shaft, thereby eliminating pressure variations among the high-pressure chambers and reducing the impact torque. An apparatus by which the generator can be smoothly driven, a high-precision impact torque can be generated, and the number of blades that can be freely inserted into and retracted from the blade insertion groove of the main shaft is three or more. The complexity of the entire structure can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire hydraulic impact wrench incorporating an impact torque generating device of the present invention.

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

FIGS. 3A and 3B are cross-sectional views of FIG. 2, wherein FIG. 3A is a cross-sectional view taken along line AA, FIG. 3B is a cross-sectional view taken along line BB, and FIG.

FIG. 4 is a diagram showing an operation state of the impact torque generating device of the present invention.

FIG. 5 is a development view of a main shaft and a liner.

FIG. 6 is a development view of a main shaft and a liner.

FIG. 7 is a development view of a main shaft and a liner.

FIG. 8 is a development view of a main shaft and a liner.

FIG. 9 is a development view of a main shaft and a liner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Main valve 3 Forward / reverse rotation switching valve 4 Rotor 5 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 15 Blade insertion groove 16a communication hole 16b communication hole H high pressure chamber L low pressure chamber P1 port P2 port S spring

Claims (1)

(57) [Claims] 1. A striking torque of a hydraulic torque wrench, which is rotated by a rotor and has a liner having a cavity and a sealing surface therein, and a main shaft coaxially disposed inside the liner and having a blade and a sealing surface. In the generator, the liner has a plurality of 2n or more sealing surfaces of 6 or more, and n sealing surfaces of the sealing surfaces are mutually 360
/ N degrees of rotational symmetry, the other n sealing surfaces are:
Each of the sealing surfaces is disposed at substantially the middle of the n number of mutually 360 / n-degree rotationally symmetrical sealing surfaces and at a position where each of the sealing surfaces is rotationally asymmetrical with respect to each other by 360 / n-degrees. , N blades and n sealing surfaces, and the n blades are removably fitted into blade insertion grooves provided at positions where each blade is rotationally symmetric with respect to 360 / n degrees, The n
The sealing surfaces are each approximately halfway between the n blades, the respective sealing surfaces are rotationally asymmetrical by 360 / n degrees with respect to each other, and the number of the liner is n per rotation of the liner.
360 / n-degree rotationally symmetric sealing surfaces and n of the main shaft
When the number of blades coincides with each other, the n pieces of the liner are disposed at the same position as the 360 ° / n-degree rotationally asymmetrical sealing surface once and at the same time, and the blade insertion grooves provided on the main shaft are connected to each other. With a bottomed groove that does not communicate with the
Two sets of communication holes communicating with one another in every other said liner inside the cavity defined by the sealing surface and the blade and the sealing surface of the spindle of the liner between the blade insertion groove and the sealing surface of the spindle, the blade insert The hitting torque generating device for a hydraulic torque wrench according to claim, wherein the hitting torque generating device is formed so as not to communicate with the groove .