JP6762572B2 - Impact torque generator for hydraulic torque wrench - Google Patents

Description

The present invention relates to a striking torque generator of a hydraulic torque wrench.

As a striking torque generator of a torque wrench, a hydraulic torque wrench using a hydraulic striking torque generator with less noise and vibration has been developed and put into practical use.
FIG. 21 shows an example of the hydraulic torque wrench, and the main body 1 of the hydraulic torque wrench selectively generates a striking torque of forward and reverse rotation with the main valve 2 that supplies and stops high-pressure air. It has a forward / reverse rotation switching valve 3 for causing the rotation, and drives a rotor 4 that generates a rotation torque by high-pressure air supplied from the valves 2 and 3. Then, a hydraulic striking torque generator 5 that converts 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 of the hydraulic torque wrench. In this hydraulic impact torque generator 5, one or more liners 8 are provided in the liner case 7, the liner 8 is filled with hydraulic oil, and the main shaft 9 is coaxially inserted into the liner 8. The blade B is inserted into the blade insertion groove, and the blade B is always urged by the spring S in the outer peripheral direction of the main shaft to abut on the inner peripheral surface of the liner 8 and the main shaft 9 is provided. One or more sealing surfaces are formed on the outer peripheral surface. Further, the liner 8 is provided with an output adjusting mechanism 10 for adjusting the magnitude of the striking torque. Then, by rotating the liner 8 with the rotor 4, when the plurality of sealing surfaces formed on the inner peripheral surface of the liner 8 and the sealing surfaces and blades B formed on the outer peripheral surface of the main shaft 9 match, the main shaft 9 is formed. It generates a striking torque.

By the way, in the case of a striking torque generator of a conventional hydraulic torque wrench, one or a plurality of blade insertion grooves are provided in the main shaft 9, blades B are fitted and inserted into the blade insertion grooves, and the blades B are used as springs S. Since the structure is always urged in the outer peripheral direction of the spindle to come into contact with the inner peripheral surface of the liner 8, the energy loss due to the sliding resistance between the tip of the blade B and the inner peripheral surface of the liner 8 is large, and the energy loss is large. There is a problem that the temperature of the hydraulic oil rises due to the frictional heat generated by this sliding, and the output of the torque wrench fluctuates due to the change in the viscosity of the hydraulic oil. Further, since it is necessary to provide a blade insertion groove and a hole for inserting the spring S in the main shaft 9, the diameter of the main shaft 9 must be increased in order to maintain the strength of the main shaft 9, and the device itself is accompanied by this. The size of the device is increased, the structure of the device is complicated, and the durability of the device is also problematic, such as damage to the spring S.

In order to deal with this problem, the applicant has first eliminated the blade B that is always urged by the spring S in the outer peripheral direction of the spindle from the impact torque generator of the hydraulic torque wrench, thereby reducing the sliding resistance and energy. We have proposed a striking torque generator for a hydraulic torque wrench that is efficient, has a small temperature rise of hydraulic fluid, provides stable output, is compact, has a simple structure, and is durable (see Patent Document 1). ..

Japanese Unexamined Patent Publication No. 7-328944

The basic structure of the hydraulic torque wrench itself is the same as that of the conventional hydraulic torque wrench shown in FIG. 21, and the hydraulic torque wrench has a striking torque of forward and reverse rotation with the main valve 2 that supplies and stops high-pressure air. It has a forward / reverse rotation switching valve 3 for selectively generating the above, and drives a rotor 4 that generates a rotation torque by high-pressure air supplied from the valves 2 and 3. Then, a hydraulic striking torque generator 5 that converts 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 of the hydraulic torque wrench.

In the hydraulic impact torque generator 5, as shown in FIGS. 1 to 6, a liner 11 is provided in the liner case 7, the liner 11 is filled with hydraulic oil and sealed, and the main shaft 9 is coaxially inside the liner 11. Is inserted.

In the liner 11 into which the main shaft 9 is inserted, a substantially elliptical hollow portion is formed inside, and four sealing surfaces 11a and 11b are formed in a mountain shape in a mountain shape on the inner peripheral surface thereof. A set of sealing surfaces, that is, the sealing surface 11a and the sealing surface 11b are formed at positions that are 180 ° rotationally symmetric. The outer circumference of the cylindrical liner 11 is supported by a liner case 7, and a liner upper lid 12 and a liner lower lid 13 are arranged at both ends of the liner 11, and the liner 11, the liner upper lid 12 and the liner lower lid 13 are separated from each other. By inserting the knock pins 17 into the pin holes provided in the liner 11, the pin holes 12a and 13a provided in the liner upper lid 12 and the liner lower lid 13, respectively, the knock pins 17 are configured to rotate integrally. Then, the liner upper lid 12 is further fixed in the axial direction with the liner case lid 7a to seal the hydraulic oil filled inside the liner 11.

On the main shaft 9 coaxially arranged inside the liner 11, two protrusions 15a and 15b having a smooth surface are formed at positions that are 180 ° rotationally symmetric.
The two protrusions 15a and 15b of the main shaft 9 operate at both ends in the axial direction and the tip in the circumferential direction by forming the lengths in the axial direction and the circumferential direction to be shorter than the hollow portion inside the liner 11. It is configured to form a passage for oil to flow.

Two driving blades 14a and 14b having a substantially triangular cross section and the same size having a smooth surface formed in a cavity formed inside the liner 11 and partitioned by protrusions 15a and 15b of the main shaft 9 are provided. Insert. The two driving blades 14a and 14b have substantially the same axial length as the hollow portion inside the liner 11 so that the side surfaces of the driving blades 14a and 14b are in sliding contact with the inner surfaces of the liner upper lid 12 and the liner lower lid 13. Along with forming the length, sealing surfaces corresponding to the sealing surfaces 11a and 11b of the liner 11 are formed in the vicinity of both ends thereof, and the sealing surfaces 11a and 11b of the liner 11 and the driving blades 14a and 14b are formed per rotation of the liner 11. It is configured so that the sealing surfaces meet twice.

The outer peripheral surface of the liner 11 is provided with a communication groove 16 that communicates with each other a hollow portion that becomes a low pressure chamber L inside the liner 11 that is partitioned by the driving blades 14a and 14b and the seal surfaces 11a and 11b of the liner 11.

Further, the liner 11 is provided with an output adjusting mechanism 10 for adjusting the magnitude of the striking torque parallel to the axis of the liner 11. This output adjusting mechanism 10 is a conventionally known one, and has a cavity portion serving as a high pressure chamber H and a low pressure chamber L inside the liner 11 partitioned by the driving blades 14a and 14b and the sealing surfaces 11a and 11b of the liner 11. It is composed of ports 10a and 10b that communicate with the cavity, and an output adjusting valve 10c that is adjustablely screwed into a screw hole 13b provided in the liner lower lid 13.

Explaining the operation of the striking torque generator 5 of the hydraulic torque wrench, first, when the main valve 2 and the switching valve 3 are operated to introduce high-pressure air into the rotor chamber in the main body 1, the rotor 4 rotates at high speed. The rotational force of this rotor is transmitted to the liner 11.

Due to the rotation of the liner 11, the inside of the liner case 7 changes as shown in FIGS. 6 (a) → (b) → (c) → (d) → (a). FIG. 6A shows a state in which no striking torque is generated on the spindle 9, and shows a state in which the liner 11 is rotated by approximately 90 ° from this, as shown in (b), (c) and (d).

The striking torque is generated on the spindle 9 as shown in FIGS. 6 (b) and 6 (d). The sealing surfaces 11a and 11b of the liner 11 and the sealing surfaces of the driving blades 14a and 14b match, and the inside of the liner 11 is generated. The cavity is divided into four chambers, and due to the shape of the cavity inside the liner 11, the volume on the high pressure chamber H side decreases and the volume on the low pressure chamber L side increases at the moment when the striking torque is generated on the spindle 9. , Each chamber becomes a high pressure chamber H and a low pressure chamber L. That is, when the liner 11 is rotated by the rotor 4 and reaches a position where the sealing surfaces 11a and 11b of the liner 11 and the sealing surfaces of the driving blades 14a and 14b match, the respective chambers become the high pressure chamber H and the low pressure chamber L. When the driving blades 14a and 14b are pushed toward the low pressure chamber L side, the sealing surfaces 11a and 11b of the liner 11 and the sealing surfaces of the driving blades 14a and 14b are matched, and the hollow portion inside the liner 11 is completely sealed. In this state, the rotational force of the liner 11 acts on the protrusions 15a and 15b of the main shaft 9 via the driving blades 14a and 14b to generate a striking torque on the main shaft 9. Then, the main shaft 9 is rotated by the striking torque generated intermittently twice for each rotation of the liner 11, and desired operations such as tightening and loosening of bolts and nuts are performed.

On the other hand, in the cases shown in FIGS. 6A and 6C, when the sealing surfaces 11a and 11b of the liner 11 and the sealing surfaces of the driving blades 14a and 14b come to a position where they match, each chamber instantly becomes a high-pressure chamber H. However, when the driving blades 14a and 14b are pushed toward the low pressure chamber L side, the sealing surfaces 11a and 11b of the liner 11 and the sealing surfaces of the driving blades 14a and 14b do not match, and the inside of the liner 11 Since the hydraulic oil on the high pressure chamber H side flows to the low pressure chamber L side through the gap between the two sealing surfaces without the hollow portion of the above being sealed, no striking torque is generated on the spindle 9.

Further, when the rotor 4 is rotated in the opposite direction, the inside of the liner case 7 changes as shown in FIGS. 6 (d) → (c) → (b) → (a) → (d) .... A striking torque in the opposite direction to the previous one can be generated in the spindle 9.

Here, the basic structure is the same as the above example, but the hydraulic impact torque generator 5 can also be configured as shown in FIGS. 7 to 12.

In this hydraulic impact torque generator 5, a liner 21 is provided in a liner case 7, the liner 21 is filled with hydraulic oil and sealed, and a spindle 9 is coaxially inserted into the liner 21.

In the liner 21 into which the main shaft 9 is inserted, a substantially elliptical hollow portion is formed inside, and four sealing surfaces 21a and 21b are formed in a mountain shape in a mountain shape on the inner peripheral surface thereof. A set of sealing surfaces, that is, the sealing surface 21a and the sealing surface 21b are formed at positions that are rotationally symmetric by 180 degrees. The outer circumference of the cylindrical liner 21 is supported by a liner case 7, and a liner upper lid 22 and a liner lower lid 23 are arranged at both ends of the liner 21, and the liner 21, the liner upper lid 22 and the liner lower lid 23 are separated from each other. By inserting knock pins (not shown) into the pin holes provided in the liner 21, the pin holes 22a and 23a provided in the liner upper lid 22 and the liner lower lid 23, respectively, the liner is configured to rotate integrally. Then, the liner upper lid 22 is further fixed in the axial direction with the liner case lid 7a to seal the hydraulic oil filled inside the liner 21. Further, on the inner surfaces of the liner upper lid 22 and the liner lower lid 23, guide grooves 22c and 23c are formed so as to be eccentric with the rotation axis O of the liner 21 so that the eccentric direction is 180 degrees rotationally symmetric. Further, the liner lower lid 23 is formed with a pin hole 23e and a hydraulic oil injection hole 23f. By inserting a pin 28 penetrating the liner case 7 into the pin hole 23e, the liner case 7 and the liner lower lid 23 are prevented from rotating.

On the main shaft 9 coaxially arranged inside the liner 21, two protrusions 25a and 25b having a smooth surface are formed at positions that are rotationally symmetric by 180 degrees. The two protrusions 25a and 25b of the main shaft 9 operate at both ends in the axial direction and the tip in the circumferential direction by forming the lengths in the axial direction and the circumferential direction to be shorter than the hollow portion inside the liner 21. It is configured to form a passage for oil to flow.

Two driving blades 24a, 24b having a substantially triangular cross section and the same size having a smooth surface formed in a cavity formed inside the liner 21 and partitioned by protrusions 25a and 25b of the main shaft 9 are provided. Insert. The two driving blades 24a and 24b have substantially the same axial length as the hollow portion inside the liner 21 so that the side surfaces of the driving blades 24a and 24b are in sliding contact with the inner surfaces of the liner upper lid 22 and the liner lower lid 23. It is formed to have a length, and a sealing surface corresponding to the sealing surfaces 21a and 21b of the liner 21 is formed in the vicinity of both ends thereof, and an inner surface of the liner upper lid 22 and the liner lower lid 23 is formed on one side surface of the driving blades 24a and 24b. Pins 27a and 27b to be fitted into the guide grooves 22c and 23c formed in the above are formed, the pin 27b of the driving blade 24b is formed in the guide groove 22c of the liner upper lid 22, and the pin 27b of the driving blade 24a is formed in the guide groove 23c of the liner lower lid 23. When 27a is inserted and inserted, and the sealing surfaces 21a and 21b of the liner 21 and the sealing surfaces of the driving blades 24a and 24b try to match twice per rotation of the liner 21, one of them is the liner upper lid 22. The movement of the driving blades 24a and 24b is regulated by the pins 27a and 27b of the driving blades 24a and 24b fitted in the guide grooves 22c and 23c formed on the inner surface of the liner lower lid 23 eccentrically with the rotation shaft O of the liner 21. By doing so, the matching is prevented, so that the spindle 9 is configured to generate one striking torque for each rotation of the liner 21.

On the outer peripheral surface of the liner 21, a communication groove 26 is provided which communicates with each other a cavity portion which is a low pressure chamber L inside the liner 21 which is partitioned by the driving blades 24a and 24b and the sealing surfaces 21a and 21b of the liner 21.

Further, the liner 21 is provided with an output adjusting mechanism 10 for adjusting the magnitude of the striking torque parallel to the axis of the liner 21. This output adjusting mechanism 10 is a conventionally known one, and includes a cavity portion that serves as a high pressure chamber H and a low pressure chamber L inside the liner 21 that is partitioned by the driving blades 24a and 24b and the sealing surfaces 21a and 21b of the liner 21. It is composed of ports 10a and 10b communicating with the cavity and an output adjusting valve 10c adjusted from an operation hole 23b provided in the liner lower lid 23.

Further, the liner 21 is provided with an accumulator 29 for absorbing the thermal expansion of the hydraulic oil in parallel with the axis of the liner 21. The accumulator 29 is composed of a piston 29a and a ventilation member 29b, and one end surface of the piston 29a is communicated with a hollow portion inside the liner 21 through a small hole 23d for an accumulator formed in a liner lower lid 23. The other end face is configured to communicate with the atmosphere through the ventilation member 29b, the accumulator small hole 22b formed in the liner upper lid 22, and the gap between the liner upper lid 22 and the liner case lid 7a.

Explaining the operation of the striking torque generator 5 of the hydraulic torque wrench, first, when the main valve 2 and the switching valve 3 are operated to introduce high-pressure air into the rotor chamber in the main body 1, the rotor 4 rotates at high speed. The rotational force of this rotor is transmitted to the liner 21.

Due to the rotation of the liner 21, the inside of the liner case 7 changes as shown in FIGS. 12 (a) → (b) → (c) → (d) → (a). FIG. 12A shows a state in which no striking torque is generated on the spindle 9, and shows a state in which the liner 21 is rotated by approximately 90 degrees from this, as shown in (b), (c) and (d).

The striking torque is generated in the spindle 9 as shown in FIG. 12B. The sealing surfaces 21a and 21b of the liner 21 and the sealing surfaces of the driving blades 24a and 24b match, and the hollow portion inside the liner 21 is formed. It is divided into 4 chambers, and due to the shape of the cavity inside the liner 21, the volume on the high pressure chamber H side decreases and the volume on the low pressure chamber L side increases at the moment when the striking torque is generated on the spindle 9, and each chamber Is a high pressure chamber H and a low pressure chamber L. That is, when the liner 21 is rotated by the rotor 4 and reaches a position where the sealing surfaces 21a and 21b of the liner 21 and the sealing surfaces of the driving blades 24a and 24b match, the respective chambers become the high pressure chamber H and the low pressure chamber L. When the driving blades 24a and 24b are pushed toward the low pressure chamber L side, the sealing surfaces 21a and 21b of the liner 21 and the sealing surfaces of the driving blades 24a and 24b are matched, and the hollow portion inside the liner 21 is completely sealed. In this state, the rotational force of the liner 21 acts on the protrusions 25a and 25b of the main shaft 9 via the driving blades 24a and 24b to generate a striking torque on the main shaft 9. Then, once for each rotation of the liner 21, the main shaft 9 is rotated by the striking torque generated intermittently to perform desired operations such as tightening and loosening of bolts and nuts.

On the other hand, when shown in FIG. 12D, the sealing surfaces 21a and 21b of the liner 21 and the sealing surfaces of the driving blades 24a and 24b try to match, but at this time, the inner surfaces of the liner upper lid 22 and the liner lower lid 23 The movement of the driving blades 24a and 24b is regulated by the pins 27a and 27b of the driving blades 24a and 24b fitted in the guide grooves 22c and 23c formed eccentrically with the rotation shaft O of the liner 21, thereby, inside the liner 21. No striking torque is generated on the spindle 9 because the hollow portion of the above is not in the sealed state.

Further, in the cases shown in FIGS. 12A and 12C, when the sealing surfaces 21a and 21b of the liner 21 and the sealing surfaces of the driving blades 24a and 24b come to a position where they match, each chamber instantly becomes a high-pressure chamber H. However, when the driving blades 24a and 24b are pushed toward the low pressure chamber L side, the sealing surfaces 21a and 21b of the liner 21 and the sealing surfaces of the driving blades 24a and 24b do not match, and the liner 21 Since the hydraulic oil on the high pressure chamber H side flows to the low pressure chamber L side through the gap between the two sealing surfaces without the internal cavity being sealed, no striking torque is generated on the spindle 9.

Further, when the rotor 4 is rotated in the opposite direction, the inside of the liner case 7 changes as shown in FIGS. 12 (d) → (c) → (b) → (a) → (d) .... A striking torque in the opposite direction to the previous one can be generated in the spindle 9.

According to the hydraulic impact torque generator 5 shown in FIGS. 1 to 6 and 7 to 12, the spring, which is indispensable for the impact torque generator of the conventional hydraulic torque wrench described in FIG. It does not require blades that are constantly urged toward the outer circumference of the spindle, has low sliding resistance, good energy efficiency, has a small temperature rise of hydraulic oil, and provides stable output. It has an advantage that a striking torque generator of a hydraulic torque wrench can be obtained.

The present invention further improves the hydraulic impact torque generator 5 shown in FIGS. 1 to 6 and 7 to 12, and has a simpler structure, more durability, less sliding resistance, and energy. It is an object of the present invention to provide a striking torque generator of a hydraulic torque wrench with higher efficiency.

In order to achieve the above object, the impact torque generator of the hydraulic torque wrench of the present invention is provided with a cavity filled with hydraulic oil, and a sealing surface is formed so as to protrude from the inner peripheral surface of the cavity. A liner that is rotated by a rotor, a main shaft that has two protrusions and is coaxially arranged inside the liner, and a liner that has sealing surfaces at both ends and is filled with hydraulic oil. A hydraulic wrench that has two driving blades that are fitted into the cavity, and the driving blades divide the inside of the liner into a high-pressure chamber and a low-pressure chamber to generate a striking torque on the spindle. In a torque wrench striking torque generator, two sealing surfaces of the liner are formed at 180 ° rotationally symmetrical positions in the cavity, and when the sealing surface of the liner and one sealing surface of each driving blade match, the other. By sliding the sealing surface against the inner peripheral surface of the cavity to seal it, the driving blade divides the inside of the liner into a high-pressure chamber and a low-pressure chamber, and a striking torque is generated on the spindle. And.

In this case, a liner is provided on one side surface of each of the driving blades by disposing a steel ball that is fitted into a guide groove formed on the inner surface of the liner upper lid and the liner lower lid to regulate the movement of the driving blade. It is possible to generate a striking torque once per rotation of the main shaft.

Further, the sealing surface of the driving blade may be formed of steel rods arranged in grooves formed at both ends of the driving blade.

Further, the cross-sectional shape of the driving blade can be formed asymmetrically.

Further, the driving blade can be made to have a magnetic force.

According to the impact torque generator of the hydraulic torque wrench of the present invention, a rotor is provided with a cavity filled with hydraulic oil and a sealing surface is formed so as to protrude from the inner peripheral surface of the cavity. It has a liner to be moved, a main shaft having two protrusions and coaxially arranged inside the liner, and sealing surfaces at both ends, and is inserted into the cavity of the liner filled with hydraulic oil. The inside of the liner is divided into a high-pressure chamber and a low-pressure chamber by the driving blades, and the impact torque of the hydraulic torque wrench is generated so as to generate the impact torque on the spindle. In the apparatus, two sealing surfaces of the liner are formed at 180 ° rotationally symmetrical positions of the cavity, and when the sealing surface of the liner and one sealing surface of each driving blade match, the other sealing surface is the cavity. By sliding and sealing the inner peripheral surface of the liner, the inside of the liner is divided into a high-pressure chamber and a low-pressure chamber by the driving blade, and a striking torque is generated on the main shaft. By configuring the sealing surface of the liner corresponding to the sealing surface of the above with the inner peripheral surface of the cavity, it is possible to substantially omit the processing step of the cavity of the liner forming this sealing surface, and the structure becomes simple. , A durable hydraulic torque wrench striking torque generator can be provided.

Further, by disposing a steel ball that is fitted into a guide groove formed on the inner surface of the liner upper lid and the liner lower lid on one side surface of each of the driving blades to regulate the movement of the driving blade, the liner 1 By making the main shaft generate a striking torque once per rotation, it is possible to provide a striking torque generating device for a hydraulic torque wrench having a small sliding resistance and a better energy efficiency.

Further, a hydraulic torque wrench having low sliding resistance and improved energy efficiency by forming the sealing surface of the driving blade with steel rods arranged in grooves formed at both ends of the driving blade. A striking torque generator can be provided.

Further, by forming the cross-sectional shape of the driving blade asymmetrically, the stability of the operation of the driving blade when used with the rotation axis in the horizontal direction is improved, and a stable and high output can be obtained. Can be done.

Further, by giving the driving blade a magnetic force, the magnetic powder generated by the wear of the parts contained in the hydraulic oil is adsorbed on the driving blade to prevent the parts from being worn by the magnetic powder. be able to. In addition, the magnetic powder adsorbed on the driving blade can be easily removed by simply wiping the driving blade during maintenance.

An example of a striking torque generator of a hydraulic torque wrench is shown, (a) is a front sectional view, and (b) is an I-I sectional view thereof. It is a figure which shows the driving blade of the impact torque generator of the same example. It is a figure which shows the spindle of the impact torque generator of the same example. It is a figure which shows the liner top lid of the impact torque generator of the same example. It is a figure which shows the liner lower lid of the impact torque generator of the same example. It is a figure which shows the operation of the impact torque generator of the same example. Other examples of the impact torque generator of the hydraulic torque wrench are shown, (a) is a front sectional view, and (b) is a II-II sectional view thereof. It is a figure which shows the driving blade of the impact torque generator of the same example. It is a figure which shows the spindle of the impact torque generator of the same example. It is a figure which shows the liner top lid of the impact torque generator of the same example. It is a figure which shows the liner lower lid of the impact torque generator of the same example. It is a figure which shows the operation of the impact torque generator of the same example. An embodiment of the impact torque generator of the hydraulic torque wrench of the present invention is shown, (a) is a front sectional view, and (b) is a III-III sectional view thereof. It is a figure which shows the operation of the impact torque generator of the same Example. It is an exploded view of the driving blade of the same Example, (a) is a front view, (b) is a side view. It is a figure which shows the output and the waveform of the comparative test by the pin and the steel ball which regulate the movement of a driving blade. A modified example of the impact torque generator of the hydraulic torque wrench of the present invention is shown, (a) is a front sectional view, (b) is an IV-IV sectional view thereof, and (c) is a side view of a driving blade. It is an exploded view of the driving blade of the modified embodiment, (a) is a front view, (b) is a side view, and (c) is a side view of a different embodiment. It is a figure which shows the operation of the impact torque generator of the said modification embodiment. It is a figure which shows the output waveform of the comparative test which concerns on the said modification example. It is a figure which shows the whole of the hydraulic impact wrench which incorporated the conventional impact torque generator.

Hereinafter, embodiments of the impact torque generator of the hydraulic torque wrench of the present invention will be described with reference to the drawings.

13 to 16 show an embodiment of the impact torque generator of the hydraulic torque wrench of the present invention.

This hydraulic impact torque generator 5 is a further improvement of the hydraulic impact torque generator 5 shown in FIGS. 1 to 6 and 7 to 12, and has a simpler structure and more durability. , The sliding resistance is small and the energy efficiency is improved.

The basic structure thereof is the same as that of the hydraulic impact torque generator 5 shown in FIGS. 1 to 6 and 7 to 12. A liner 31 is provided in the liner case 7 and operates in the liner 31. The main shaft 9 is coaxially fitted and inserted into the liner 31 by filling and sealing with oil.

A substantially elliptical hollow portion is formed inside the liner 31 into which the main shaft 9 is inserted, and two sealing surfaces 31a and 31b are formed in a mountain shape on the inner peripheral surface thereof at 180 ° rotationally symmetric positions. The outer circumference of the cylindrical liner 31 is supported by a liner case 7, and a liner upper lid 32 and a liner lower lid 33 are arranged at both ends of the liner 31, and the liner 31, the liner upper lid 32, and the liner lower lid 33 are separated from each other. By inserting knock pins (not shown) into the pin holes provided in the liner 31 and the pin holes provided in the liner upper lid 32 and the liner lower lid 33, respectively, the liner is configured to rotate integrally. Then, the liner upper lid 32 is further fixed in the axial direction with the liner case lid 7a to seal the hydraulic oil filled inside the liner 31. Further, on the inner surfaces of the liner upper lid 32 and the liner lower lid 33, guide grooves 32c and 33c are formed so as to be eccentric with the rotation axis O of the liner 31 so that the eccentric direction is 180 degrees rotationally symmetric. Further, a groove for allowing hydraulic oil to escape is formed at a predetermined position on the inner surfaces of the liner upper lid 32 and the liner lower lid 33.

Here, the hydraulic impact torque generator 5 of the present embodiment is different from the hydraulic impact torque generator 5 described in FIGS. 1 to 6 and 7 to 12, and the paired seal surfaces 31a, The other sealing surfaces 31a'and 31b' of 31b, that is, the sealing surfaces of the liner 31 corresponding to the sealing surfaces of the driving blades 34a and 34b described later, are formed by the inner peripheral surface of the cavity.
The inner peripheral surface of the cavity portion of the liner 31 constituting the sealing surfaces 31a'and 31b' has a substantially cylindrical surface shape, and the angle θ thereof is about 30 ° to 70 °, preferably about 40 ° to 60 ° (this). In the embodiment, it is formed at 50 °).
As a result, by making the mountain-shaped sealing surfaces 31a and 31b into two, it is possible to substantially omit the processing step of the hollow portion of the liner 31 forming the sealing surfaces 31a'and 31b', and the structure can be made. It becomes possible to provide a striking torque generator of a hydraulic torque wrench which is simplified and has durability.

On the main shaft 9 coaxially arranged inside the liner 31, two protrusions 35a and 35b having a smooth surface are formed at positions that are 180 ° rotationally symmetric. The two protrusions 35a and 35b of the main shaft 9 operate at both ends in the axial direction and the tip in the circumferential direction by forming the lengths in the axial direction and the circumferential direction to be shorter than the hollow portion inside the liner 31. It is configured to form a passage for oil to flow.

Two driving blades 34a, 34b having a substantially triangular cross section and the same size having a smooth surface formed in the cavity formed inside the liner 31 and partitioned by the protrusions 35a, 35b of the main shaft 9 are provided. Insert. The two driving blades 34a and 34b have substantially the same axial length as the hollow portion inside the liner 31 so that the side surfaces of the driving blades 34a and 34b are in sliding contact with the inner surfaces of the liner upper lid 32 and the liner lower lid 33. The length is formed, and the sealing surfaces corresponding to the sealing surfaces 31a, 31a', 31b, 31b'of the liner 31 are formed in the vicinity of both ends thereof, and the liner upper lid 32 and the liner upper lid 32 and one side surface of the driving blades 34a, 34b are formed. Steel balls 37a and 37b to be fitted into the guide grooves 32c and 33c formed on the inner surface of the liner lower lid 33 are arranged, and the steel balls 37b of the driving blade 34b are placed in the guide grooves 32c of the liner upper lid 32 and the liner lower lid 33. The steel balls 37a of the driving blade 34a are fitted into the guide grooves 33c, respectively, and the sealing surfaces 31a, 31a', 31b, 31b'of the liner 31 and the sealing surfaces of the driving blades 34a, 34b are met twice for each rotation of the liner 31. When trying to do this, one of them was the driving blades 34a, 34b inserted into the guide grooves 32c, 33c formed on the inner surfaces of the liner upper lid 32 and the liner lower lid 33 eccentrically with the rotation axis O of the liner 31. By restricting the movement of the driving blades 34a and 34b by the steel balls 37a and 37b of the above, the matching is prevented, whereby the main shaft 9 is configured to generate one striking torque per rotation of the liner 31.

Here, instead of the steel balls 37a and 37b inserted into the guide grooves 32c and 33c, which guide and regulate the movement of the driving blades 34a and 34b used in this embodiment, FIGS. 7 to 12 are shown. It is also possible to apply the pins 27a and 27b to be inserted into the guide grooves 22c and 23c used in the hydraulic impact torque generator 5 that guides and regulates the movement of the driving blades 34a and 34b.

Table 1 and FIG. 16 show the output (measured value by a digital torque tester) of the comparative test when the pins 27a and 27b and the steel balls 37a and 37b are used and their waveforms.

As is clear from the results of the comparative test when the pins 27a and 27b and the steel balls 37a and 37b are used, the steel balls 37a and 37b have smaller sliding resistance and higher energy efficiency than the pins 27a and 27b. It was confirmed.

As shown in FIG. 15, the sealing surfaces of the driving blades 34a and 34b can be formed of steel rods 34d arranged in the grooves 34c formed at both ends of the driving blade, if necessary.
This makes it possible to provide a striking torque generator for a hydraulic torque wrench with low sliding resistance and improved energy efficiency.

On the outer peripheral surface of the liner 31, a cavity portion serving as a low pressure chamber L inside the liner 31 partitioned by the driving blades 34a and 34b and the sealing surfaces 31a, 31a', 31b and 31b'of the liner 31 communicate with each other. A communication groove (not shown) is provided.

Further, the liner 31 is provided with an output adjusting mechanism 10 for adjusting the magnitude of the striking torque parallel to the axis of the liner 31. This output adjusting mechanism 10 is a conventionally known one, and is a hollow portion serving as a high pressure chamber H inside the liner 31 partitioned by the driving blades 24a and 24b and the sealing surfaces 31a, 31a', 31b and 31b'of the liner 31. It is composed of a port (not shown) that communicates with the hollow portion that becomes the low pressure chamber L, and an output adjusting valve 10c that is adjustablely screwed into a screw hole provided in the liner lower lid 33.

Further, the liner 31 is provided with an accumulator 39 for absorbing the thermal expansion of the hydraulic oil in parallel with the axis of the liner 31.

Explaining the operation of the striking torque generator 5 of the hydraulic torque wrench, first, when the main valve 2 and the switching valve 3 are operated to introduce high-pressure air into the rotor chamber in the main body 1, the rotor 4 rotates at high speed. The rotational force of this rotor is transmitted to the liner 31.

Due to the rotation of the liner 31, the inside of the liner case 7 changes as shown in FIGS. 14 (a) → (b) → (a). FIG. 14A shows a state in which a striking torque is generated in the main shaft 9, and FIG. 14B shows a state in which the liner 31 is rotated by approximately 180 °.

The striking torque is generated on the spindle 9 as shown in FIG. 14A, when the sealing surfaces 31a, 31a', 31b, 31b'of the liner 31 and the sealing surfaces of the driving blades 34a, 34b match, and the liner 31 The internal cavity of the liner 31 is divided into four chambers, and the volume on the high pressure chamber H side decreases and the volume on the low pressure chamber L side decreases at the moment when the impact torque is generated on the spindle 9 due to the shape of the internal cavity of the liner 31. The number of chambers increases, and each chamber becomes a high pressure chamber H and a low pressure chamber L. That is, when the liner 31 is rotated by the rotor 4 and reaches a position where the sealing surfaces 31a, 31a', 31b, 31b'of the liner 31 and the sealing surfaces of the driving blades 34a, 34b meet, each chamber becomes a high pressure chamber H. When the low pressure chamber L is formed and the driving blades 34a and 34b are pushed toward the low pressure chamber L side, the sealing surfaces 31a, 31a', 31b and 31b'of the liner 31 and the sealing surfaces of the driving blades 34a and 34b are matched. The hollow portion inside the liner 31 is completely sealed, and the rotational force of the liner 31 acts on the protrusions 35a and 35b of the main shaft 9 via the driving blades 34a and 34b to generate a striking torque on the main shaft 9. Let me. Then, the spindle 9 is rotated by the striking torque generated intermittently once for each rotation of the liner 31, and desired operations such as tightening and loosening of bolts and nuts are performed.

On the other hand, when shown in FIG. 14B, the sealing surfaces 31a, 31a', 31b, 31b'of the liner 31 and the sealing surfaces of the driving blades 34a, 34b try to match. At this time, the liner top lid 32 and the liner The movement of the driving blades 34a and 34b is regulated by the steel balls 37a and 37b of the driving blades 34a and 34b fitted in the guide grooves 32c and 33c formed on the inner surface of the lower lid 33 eccentrically with the rotation shaft O of the liner 31. As a result, the hollow portion inside the liner 31 is not in the sealed state, so that no striking torque is generated on the spindle 9.

As described above, except for the case shown in FIG. 14A, the sealing surfaces 31a, 31a', 31b, 31b'of the liner 31 and the sealing surfaces of the driving blades 34a, 34b do not match and are not sealed.

Further, when the rotor 4 is rotated in the opposite direction, a striking torque in the opposite direction can be generated in the spindle 9.

The other configurations and operations of the hydraulic impact torque generator 5 are the same as those of the hydraulic impact torque generator 5 described in FIGS. 1 to 6 and 7 to 12.

Further, as a mechanism for generating a striking torque on the spindle 9 once per rotation of the liner 31, a steel ball 37a inserted into the guide grooves 32c and 33c, which guides and regulates the movement of the driving blades 34a and 34b, 37b, pins 27a inserted into the guide grooves 22c and 23c used in the hydraulic impact torque generator 5 for guiding and regulating the movements of the driving blades 34a and 34b described in FIGS. 7 to 12. In addition to 27b, the mechanism disclosed in Patent Document 1 can be adopted.

Further, since the hydraulic impact torque generator 5 has low sliding resistance and good energy efficiency, it is 2 per rotation of the liner 31 as in the hydraulic impact torque generator 5 shown in FIGS. 1 to 6. The striking torque may be generated on the main shaft 9 times.

By the way, the hydraulic impact torque generator 5 has the above-mentioned action and effect, but has the following problems.
(1) The operation stability of the driving blade is low when the rotation axis is set in the horizontal direction.
(2) The magnetic powder generated by the wear of the parts contained in the hydraulic oil causes the parts to wear, which reduces the durability of the device.

17 to 20 show examples of modifications of the impact torque generator of the hydraulic torque wrench of the present invention that can cope with this problem.

In order to deal with the problem (1) above, in this modification, the cross-sectional shapes of the driving blades 34a and 34b are formed asymmetrically.
Specifically, as shown in FIG. 17C, in the cross-sectional shape of the driving blades 34a and 34b, the volume of the left half is reduced to the right by forming the bulging portion 34e on the left side of the center line Lo. It is made larger than half the volume so that the center of gravity is not located on the center line Lo.
As a result, as shown in FIG. 20, in particular, as compared with the case where the rotation axis is used in the direction perpendicular to the horizontal plane, the rotation axis in which the operation of the driving blades 34a and 34b is difficult to stabilize is used in the horizontal direction. The stability of the operation of the driving blades 34a and 34b is improved, and a stable and high output can be obtained.

Next, in order to deal with the problem (2) above, in this modified embodiment, the driving blades 34a and 34b are provided with magnetic force.
Specifically, as shown in FIGS. 18A and 18B, a magnet 38 is embedded in a portion that does not come into contact with other members of the driving blades 34a and 34b, or as shown in FIG. 18C, a magnet is used. In addition to attaching the 38, the driving blades 34a and 34b themselves can be magnetized.
The size (surface area and thickness) and magnetic force strength of the magnet 38 can be appropriately set depending on the amount of magnetic powder adsorbed on the driving blades 34a and 34b.
As a result, the magnetic powder generated by the wear of the parts contained in the hydraulic oil is adsorbed on the driving blades 34a and 34b without being affected by the resistance and the balance surface due to the contact with other members. It is possible to prevent the parts from being worn. Further, the magnetic powder adsorbed on the driving blades 34a and 34b can be easily removed only by wiping the driving blades 34a and 34b at the time of maintenance.

The other configurations and operations of the hydraulic impact torque generator 5 are the same as those of the hydraulic impact torque generator 5 shown in FIGS. 13 to 16.

The striking torque generator of the hydraulic torque wrench of the present invention has been described above based on the embodiment thereof, but the present invention is not limited to the configuration described in the above embodiment, for example, the motor of the drive source. As a result, in addition to the air motor, an electric motor can be used, and the configuration can be appropriately changed as long as the purpose is not deviated.

The striking torque generator of the hydraulic torque wrench of the present invention does not require blades that are constantly urged in the outer peripheral direction of the spindle by a spring, has low sliding resistance, good energy efficiency, and is stable with little temperature rise of hydraulic oil. A hydraulic torque wrench that uses an electric motor and high tightening accuracy, which cannot be expected to have an air-cooling effect due to the high-pressure air of the power source, because it has the characteristics of high output, small size, simple structure, and durability. It can be suitably used for the required hydraulic torque wrench application, and can also be used, for example, for the hydraulic torque wrench application using an air motor.

1 Main body 2 Main valve 3 Forward / reverse rotation switching valve 4 Rotor 5 Strike torque generator 6 Front case 7 Liner case 8 Liner 9 Spindle 10 Output adjustment mechanism 11 Liner 11a Liner seal surface 11b Liner seal surface 12 Liner top lid 13 Under liner Lid 14a Driving blade 14b Driving blade 15a Main shaft protrusion 15b Main shaft protrusion 16 Communication groove 17 Knock pin 21 Liner 21a Liner seal surface 21b Liner seal surface 22 Liner upper lid 22c Guide groove 23 Liner lower lid 23c Guide groove 24a Driving blade 24b Driving blade 25a Main shaft protrusion 25b Main shaft protrusion 26 Communication groove 27a Pin 27b Pin 29 Accumulator 31 Liner 31a Liner seal surface 31a'Liner seal surface 31b Liner seal surface 31b' Liner seal surface 32 Liner top lid 32c Guide groove 33 Liner lower lid 33c Guide groove 34a Driving blade 34b Driving blade 34c Groove 34d Steel rod 34e Swelling part 35a Main shaft protrusion 35b Main shaft protrusion 37a Steel ball 37b Steel ball 38 Magnet 39 Accumulator H High pressure chamber L Low pressure chamber L Lo centerline S spring

Claims (4)

A liner that is rotated by a rotor and has a cavity that is filled with hydraulic oil and has a sealing surface that projects from the inner peripheral surface of the cavity.
A spindle that has two protrusions and is coaxially arranged inside the liner,
It has sealing surfaces at both ends and has two driving blades that are fitted into the cavity of the liner filled with hydraulic oil.
In a hydraulic torque wrench striking torque generator in which the inside of the liner is divided into a high-pressure chamber and a low-pressure chamber by a driving blade to generate striking torque on the spindle.
The shape of the cross section of the driving blade is asymmetrically formed by sandwiching a line that passes through the center of the cross section of the driving blade in the longitudinal direction and intersects perpendicularly to the longitudinal direction .
Two sealing surfaces of the liner are formed at 180 ° rotationally symmetric positions of the cavity, and when the sealing surface of the liner and one sealing surface of each driving blade match, the other sealing surface is the inner circumference of the cavity. The impact of a hydraulic torque wrench is characterized in that the inside of the liner is divided into a high-pressure chamber and a low-pressure chamber by a driving blade by sliding and sealing the surface, and a striking torque is generated on the spindle. Torque generator. By arranging a steel ball that is fitted into a guide groove formed on the inner surface of the liner upper lid and the liner lower lid on one side surface of each of the driving blades to regulate the movement of the driving blade, one rotation of the liner is performed. The striking torque generating device for a hydraulic torque wrench according to claim 1, wherein a striking torque is generated once on the spindle. The impact torque generation of the hydraulic torque wrench according to claim 1 or 2, wherein the sealing surface of the driving blade is composed of steel rods arranged in grooves formed at both ends of the driving blade. apparatus. The striking torque generating device for a hydraulic torque wrench according to claim 1, 2 or 3, wherein the driving blade is provided with a magnetic force.

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