JP6145993B2 - Oil pulse tool - Google Patents

Description

  This invention rotates an oil pulse unit in which a main shaft is arranged at a central portion of a cylindrical liner filled and sealed with oil, and generates an instantaneous torque by a hydraulic pressure generated when the oil pulse unit is rotated to generate a screw. The present invention relates to an oil pulse tool for fastening work.

  This type of oil pulse tool includes a cylindrical liner, a main shaft that rotates while being inserted into the liner, and a blade that is inserted into the outer periphery of the main shaft and can project in the radial direction. The basic configuration is to rotate the liner, compress the oil in the oil chamber, and generate the rotational torque of the main shaft by the blade that receives the hydraulic pressure.

  Here, in the conventional oil pulse tool, the seal portion of the liner is formed to protrude in a rib shape from the inner wall of the liner (see, for example, Patent Documents 1 to 3).

Japanese Patent No. 3382043 Japanese Patent No. 4820027 Japanese Patent No. 3615125

  However, in the conventional oil pulse tool as described above, since the gap between the liner seal portion and the main shaft seal portion (or blade) is sudden when the oil pulse unit is rotated, the torque rises. The omission is sudden. This is an oil pulse mechanism that does not collide between metals and is low noise. However, when such a sudden torque change occurs, the reaction of the impact is transmitted to the screw and the member to be fastened, and those vibrations lead to the generation of sound. There was a problem.

  Therefore, the present invention reduces the reaction caused by a sudden torque change, the generated sound and vibration generated by a screw or a member to be fastened, by slowing the rise and drop of the hydraulic pressure when the oil pulse unit is rotated. It is an object of the present invention to provide an oil pulse tool that can be used.

  The present invention has been made to solve the above-described problems, and is characterized by the following.

(Claim 1)
The invention described in claim 1 is characterized by the following points.

That is, the oil pulse tool according to claim 1 is disposed in a cylindrical liner filled and sealed with oil, a main shaft rotatably supported in the liner, and retractable on a side portion of the main shaft. A plurality of oil chambers are formed by dividing the interior of the liner by the main shaft and the blades, and a pressure difference is generated between the plurality of oil chambers by rotating the liner. An oil pulse tool for generating torque, wherein a blade sliding surface for sliding the blade is formed in the vicinity of the opening at both ends on the inner peripheral surface of the liner, and the blade sliding on both sides An inner wall surface that is recessed in the outer diameter direction with respect to the blade sliding surface is formed between the surfaces, and the inner wall surface includes an oil chamber forming portion that forms a wall portion of the oil chamber, and an oil chamber forming portion of the oil chamber forming portion. Between Vignetting provided with a liner seal portion projecting radially inward to be substantially the same volume as the blade sliding surface, thereby forming the oil chamber forming portion is arcuate surface, said liner seal portion, said A circular arc surface that uses a part of a circle that is concentric with the liner is formed, and between the oil chamber forming portion and the liner seal portion, the oil chamber forming portion and the arc surface of the liner seal portion Is provided with a connecting portion that is formed by another curved surface and bulges toward the center of the liner, and the oil chamber forming portion, the connecting portion, and the liner seal portion alternately protrude in the opposite direction and are smooth. It is characterized by being continuous .

(Claim 2 )
The invention described in claim 2 has the following features in addition to the features of the invention described in claim 1 described above.

  That is, a main shaft seal portion that abuts on the liner seal portion protrudes from the outer peripheral surface of the main shaft, and a rising portion that continues to the main shaft seal portion is formed as a curved surface. To do.

  The invention according to claim 1 is as described above, and since the connecting portion that is continuous with the liner seal portion is formed in a curved surface in the oil chamber forming portion, the liner seal portion and the main shaft seal portion are rotated when the liner is rotated. Since the gap area gradually decreases as the distance (or blade) approaches, the torque rises and falls slowly, and the reaction, generated sound, and vibration associated with a sudden torque change can be reduced. Further, since the recoil becomes small, the load on the motor can be reduced, and the cam-out and bit breakage are less likely to occur.

In addition , the oil chamber forming portion is formed with an arc surface, and the connecting portion is formed with a curved surface different from the arc surface of the oil chamber forming portion, so that the connecting portion leads to the liner seal portion. Since the surfaces are smoothly continuous, torque fluctuation can be further moderated.

According to a second aspect of the present invention, a main shaft seal portion that comes into contact with the liner seal portion is protruded and formed on the outer peripheral surface of the main shaft, and a rising portion that is continuous with the main shaft seal portion is formed with a curved surface. . For this reason, the clearance area gradually decreases as the liner seal part and the main shaft seal part approach each other. Can be reduced. Further, since the recoil becomes small, the load on the motor can be reduced, and the cam-out and bit breakage are less likely to occur.

It is a side view of an oil pulse driver. It is the partially expanded sectional view which looked at the oil pulse driver from the side. It is sectional drawing which looked at the oil pulse unit from the side. It is AA sectional drawing of an oil pulse unit. It is a perspective view of a liner. It is sectional drawing of a liner, Comprising: (a) without an auxiliary line, (b) is the figure which attached | subjected the auxiliary line for demonstrating the shape of an inner wall surface. It is the graph which compared the torque change with the conventional product, and the graph which compared the change of the clearance gap area between a liner seal part and a main shaft seal part with a conventional product. It is the graph which compared the vibration and sound which an oil pulse driver generates with the conventional product. It is sectional drawing of the liner which concerns on a modification, Comprising: (a) without an auxiliary line, (b) is the figure which attached the auxiliary line for demonstrating the shape of an inner wall surface. It is (a) perspective view of the main shaft which concerns on a modification, (b) It is sectional drawing.

  An embodiment of the present invention will be described with an oil pulse driver 10 as an example of an oil pulse tool, with reference to the drawings.

  In the oil pulse driver 10 according to the present embodiment, an oil pulse unit 21 having a main shaft 27 disposed at the center of a cylindrical liner 26 filled and sealed with oil is operatively connected to the motor 12, and the oil pulse unit 21 is rotated. A periodic torque is generated by the generated hydraulic pressure, and the main shaft 27 is rotated to perform a screw tightening operation. As shown in FIGS. 1 and 2, a drive unit 11 including a motor 12 and a planetary gear reduction mechanism are provided. The speed reduction part 13 provided and the pulse part 20 provided with the oil pulse unit 21 are arranged in series in the front and rear and accommodated in the housing 14.

  A grip 15 is provided below the housing 14, and the motor 12 is rotated by operating a trigger 16 provided on the grip 15, and the rotated motor 12 drives the oil pulse unit 21. When the oil pulse unit 21 is driven, as will be described later, the main shaft 27 disposed in the center of the oil pulse unit 21 is shockedly rotated by the oil pulse. A rechargeable battery 17 is detachably disposed below the grip 15 and is used as a power source for the motor 12.

  In front of the motor 12, a planetary gear speed reduction mechanism constituting the speed reduction unit 13 is disposed, and the planetary gear included in the planetary gear speed reduction mechanism is engaged with a gear shaft directly connected to the output shaft of the motor 12. Thereby, when the motor 12 is operated, the driving force of the motor 12 is decelerated by the planetary gear reduction mechanism, and the reduced driving force of the motor 12 is transmitted to the oil pulse unit 21 arranged in front of the speed reduction unit 13. The

  As shown in FIG. 3, the oil pulse unit 21 includes a main shaft 27 and a liner 26 in a cylindrical liner case 25 closed by a lower cap 23, an upper cap 22 and a liner cap 24 provided at both ends. Is placed and filled with oil.

  The rear end of the main shaft 27 is pivotally supported by the upper cap 22, and the front side portion is supported through the lower cap 23. The front end of the main shaft 27 protrudes forward of the liner case 25, and a bit or the like (not shown) can be attached.

  As shown in FIG. 4, a blade groove 27c is formed in the side portion of the main shaft 27 in a diametrical direction, and a pair of blades 28 are disposed in the blade groove 27c so as to be able to appear and retract. The pair of blades 28 are connected to each other via a blade spring 29 so as to expand and contract, and are always urged to contact the inner surface of the liner 26.

  Oil is sealed inside the liner 26, and the oil seal 30 is divided by the main shaft 27 and the blades 28 to form four oil chambers 30. The oil pulse driver 10 according to the present embodiment is formed such that when the liner 26 is rotated by the driving force of the motor 12, a pressure difference is generated between the four oil chambers 30, and torque is generated by the pressure difference. .

  The liner 26 is a metal cylindrical member as shown in FIG. 5, and a blade sliding surface 26 a for sliding the blade 28 is formed in the vicinity of the openings at both ends on the inner peripheral surface of the liner 26. In addition, an inner wall surface 26b that is recessed in the outer diameter direction with respect to the blade sliding surface 26a is formed between the blade sliding surfaces 26a on both sides.

  The inner wall surface 26b is provided between the oil chamber forming portion 26c that forms the wall portion of the oil chamber 30 and the oil chamber forming portion 26c, and is continuously provided so as to have substantially the same amount as the blade sliding surface 26a. A liner seal portion 26e projecting in the inner diameter direction, and a connecting portion 26d continuous with the liner seal portion 26e is formed at the end of the oil chamber forming portion 26c.

  As shown in FIG. 6, the oil chamber forming portions 26c are provided at a total of four locations, and the liner seal portions 26e are also provided at a total of four locations between the four oil chamber forming portions 26c. The connecting portions 26d are provided at a total of eight locations at both ends of the oil chamber forming portion 26c (both ends of the liner seal portion 26e).

  In the present embodiment, as shown in FIG. 6B, the four oil chamber forming portions 26c are each formed by a circular arc surface using a part of a circle R1 having the same diameter. The circle R1 is a circle eccentric with respect to the center of the liner 26.

  On the other hand, as shown in FIG. 6A, the liner seal portion 26e is provided at two places on the top and bottom and two places on the left and right. As shown in FIG. 6B, the two left and right liner seal portions 26 e are formed by arcuate surfaces using a part of a circle R 2 that is concentric with the liner 26. Further, the two upper and lower liner seal portions 26e are formed as arcuate surfaces using a part of an eccentric circle R3 that is eccentric with respect to the center of the liner 26, as shown in FIG.

  The connecting portion 26d provided between the oil chamber forming portion 26c and the liner seal portion 26e is formed with a curved surface different from the arc surface of the oil chamber forming portion 26c and the arc surface of the liner seal portion 26e. Yes. Specifically, the connecting portion 26 d of the present embodiment is formed by an arc surface that bulges toward the center of the liner 26. As a result, the surface from the connecting portion 26d to the liner seal portion 26e is smoothly continuous.

  A main shaft seal portion 27a that contacts the liner seal portion 26e protrudes from the outer peripheral surface of the main shaft 27, and the liner 26 is rotated to a position where the main shaft seal portion 27a and the liner seal portion 26e face each other. By doing so, the oil chamber 30 is formed so as to be substantially sealed.

  The oil pulse driver 10 thus formed operates as follows.

  That is, when the screw tightening operation is performed by the oil pulse driver 10, the trigger 12 is pulled to rotate the motor 12, and the rotational force reduced by the planetary gear is transmitted to the oil pulse unit 21. Thus, when the liner 26 rotates, the main shaft 27 rotates due to the blade 28 receiving the oil pressure. Thus, when no load is applied to the main shaft 27, the main shaft 27 rotates only with the resistance of oil.

  On the other hand, when the load on the main shaft 27 increases, the rotation of the main shaft 27 is delayed with respect to the rotation of the liner 26, and as shown in FIG. 4, the liner seal portion 26e and the main shaft seal portion 27a (or the blade 28). ) Approaches, the gap area between the liner seal portion 26e and the main shaft seal portion 27a (or blade 28) becomes smaller, so that the oil cannot escape and the oil is compressed. The oil is compressed in this way to generate a hydraulic pressure, and the main shaft 27 is rotated instantaneously by the hydraulic pressure. In this way, by generating a large torque at a constant cycle, the screw or the like is tightened strongly.

  At this time, the oil chamber forming portion 26c of the present embodiment is formed with a circular arc surface, and further, since the connecting portion 26d is formed with a curved surface, the surface from the oil chamber forming portion 26c to the liner seal portion 26e is smooth. Therefore, as the liner 26 rotates and the liner seal portion 26e and the main shaft seal portion 27a (or the blade 28) approach each other, the clearance area gradually decreases. For this reason, it is possible to moderate the rise and drop of torque, and to reduce the reaction, generated sound, and vibration associated with a sudden torque change. Further, since the recoil becomes small, the load on the motor 12 can be reduced, and the cam-out and bit breakage are less likely to occur.

  FIG. 7 is a graph comparing the torque change of the oil pulse driver 10 according to the present embodiment with the conventional product, and a graph comparing the change in the clearance area between the liner seal portion 26e and the main shaft seal portion 27a with the conventional product. It is. The conventional product is an oil pulse driver provided with a liner seal portion (a liner seal portion formed by protruding in a rib shape from the inner wall of the liner) as shown in Patent Documents 1 to 3. As is apparent from this graph, the oil pulse driver 10 according to the present embodiment has a moderate torque rise and drop, although the maximum torque value is almost the same as that of the conventional product. Moreover, in the conventional product, since the torque vibrates after the oil is removed, it can be seen that the main shaft 27 is shaken by the reaction after the oil is removed, and the forward and reverse rotations are repeated. In this regard, such movement is suppressed in the oil pulse driver 10 according to the present embodiment.

  FIG. 8 is a graph comparing vibration and sound generated by the oil pulse driver 10 according to the present embodiment with those of a conventional product. As is apparent from this graph, it can be seen that the oil pulse driver 10 according to the present embodiment is significantly suppressed in vibration and sound as compared with the conventional product. This is because it is possible to reduce the reaction and sound generated due to the rapid torque change as described above, and to suppress the vibration caused by the main shaft 27 repeating forward and reverse rotations.

  Thus, according to this embodiment, since the connecting portion 26d that is continuous with the liner seal portion 26e is formed in a curved surface at the end of the oil chamber forming portion 26c, the liner seal portion 26e and the main shaft seal portion 27a. Since the gap area gradually decreases as the blade (or the blade 28) approaches, it is possible to moderate the rise and drop of torque, and to reduce the reaction, generated sound, and vibration associated with a sudden torque change. Further, since the recoil becomes small, the load on the motor can be reduced, and the cam-out and bit breakage are less likely to occur.

  In the above-described embodiment, the four oil chamber forming portions 26c are each formed as an arc surface using a part of another circle R2, but as an embodiment of the present invention, Not limited to this. For example, as shown in FIG. 9, two of the four oil chamber forming portions 26c are formed by arc surfaces using a part of the same circle R5, and the other two are different circles having the same diameter. You may form by the circular arc surface using a part of. Also at this time, the liner seal portion 26e may be formed by an arc surface using a part of a circle R4 that is concentric with the liner 26.

  In the above-described embodiment, the connecting portion 26d is formed by an arc surface that bulges toward the center of the liner 26. However, the embodiment of the present invention is not limited thereto. For example, as shown in FIG. 9, it may be formed as a gentle curved surface connecting the end of the oil chamber forming portion 26c and the end of the liner seal portion 26e. Further, although not particularly illustrated, a circular arc surface or a chamfered shape may be provided at a corner portion of the liner seal portion 26e protruding in a rib shape, and this may be used as the connection portion 26d.

  Further, in the above-described embodiment, the change in the gap area is reduced by making the connecting portion 26d a curved surface, but instead of this, or together with this, the rising portion 27b continuous to the main shaft seal portion 27a is provided. You may form with a curved surface. For example, as shown in FIG. 10, by making a part of the outer peripheral surface of the main shaft 27 into an arcuate shape, the main shaft seal portion 27a is projected and the rising portion 27b of the main shaft seal portion 27a is projected. May be formed of a curved surface. Even when formed in this way, the clearance area gradually decreases as the liner seal portion 26e and the main shaft seal portion 27a approach each other, so that the torque rise and drop can be moderated, resulting in a sudden torque change. Reaction, sound generation, and vibration can be reduced. Further, since the recoil becomes small, the load on the motor 12 can be reduced, and the cam-out and bit breakage are less likely to occur.

DESCRIPTION OF SYMBOLS 10 Oil pulse driver 11 Drive part 12 Motor 13 Deceleration part 14 Housing 15 Grip 16 Trigger 17 Battery 20 Pulse part 21 Oil pulse unit 22 Upper cap 23 Lower cap 24 Liner cap 25 Liner case 26 Liner 26a Blade sliding surface 26b Inner wall surface 26c Oil chamber forming portion 26d Connection portion 26e Liner seal portion 27 Main shaft 27a Main shaft seal portion 27b Rising portion 27c Blade groove 28 Blade 29 Blade spring 30 Oil chamber

Claims (2)

A cylindrical liner filled and sealed with oil;
A main shaft rotatably supported in the liner;
A blade disposed so as to be capable of appearing and retracting on a side portion of the main shaft;
With
An oil pulse tool that generates a torque by generating a pressure difference between the plurality of oil chambers by rotating the liner by dividing the interior of the liner by the main shaft and the blade to form a plurality of oil chambers. Because
On the inner peripheral surface of the liner, a blade sliding surface for sliding the blade is formed in the vicinity of the opening at both ends, and between the blade sliding surfaces on both sides with respect to the blade sliding surface. An inner wall surface that is recessed in the outer diameter direction is formed,
The inner wall surface is provided between the oil chamber forming portion that forms the wall portion of the oil chamber and the oil chamber forming portion, and protrudes in the inner diameter direction so as to have substantially the same protruding amount as the blade sliding surface. A liner seal portion,
The oil chamber forming portion is formed with an arc surface, and the liner seal portion is formed with an arc surface using a part of a circle that is concentric with the liner,
A connecting portion that is formed between the oil chamber forming portion and the liner seal portion with a curved surface different from the arc surface of the oil chamber forming portion and the liner seal portion and bulges toward the center of the liner. Is provided ,
The oil pulse tool, wherein the oil chamber forming portion, the connecting portion, and the liner seal portion alternately protrude in opposite directions and are continuously continuous . A main shaft seal portion that abuts on the liner seal portion protrudes from the outer peripheral surface of the main shaft, and a rising portion that continues to the main shaft seal portion is formed as a curved surface. The oil pulse tool according to claim 1 .

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