JP2007326172A - Hydraulic torque wrench - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic torque wrench which efficiently outputs a torque with a simple structure. <P>SOLUTION: The hydraulic torque wrench comprises a cylinder 20 supporting an output shaft 10 and having a plurality of protuberances 31 formed on a side wall inner face, and guide grooves 16 are formed to the output shaft 10 at intervals corresponding to the protuberances 31. A cam member 50 rotating together with the cylinder 20 is held in a housing hole 14 in the output shaft 10, and slide members 40 received by the respective guide grooves 16 comprise outside portions 41, and inside portions 42 projected in the housing hole 14 at one portion. A plurality of the slide members 40 comprise inside portions 42 at different portions in an axial line direction. A cam member comprises a plurality of flat parts 54, 55, and the flat parts are arranged corresponding to the respective slide members so that the slide members 40 contacts the protuberances 31 every rotation of the cam member. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hydraulic torque wrench that applies rotational torque and torque for tightening or loosening to screw fitting members such as bolts and nuts and other rotating members.

  This type of hydraulic torque wrench is configured to rotationally drive a cylinder in which a fluid tight chamber is formed and contains hydraulic oil, and to transmit a driving force to an output shaft protruding forward from the cylinder. For the transmission, in the liquid tight chamber, a pair of opposed raised portions and a pair of sealing projections opposed in a direction perpendicular to these are provided on the inner peripheral surface of the cylinder, and the output shaft is radially arranged A structure is adopted in which a pair of sliding members and a pair of seal protrusions are provided in the cylinder, and a cam member that rotates with the cylinder and extends and slides out from the rear end of the cylinder into the shaft hole of the output shaft. Has been. Thereby, with the rotation of the cylinder, the liquid-tight chamber is divided at a position where the raised portion and the protruding sliding member, and the sealing projection and the sealing projection contact each other. When the cylinder rotates at a high speed in this state, the driving force is transmitted at a high pressure formed in the divided chamber to push the sliding member around the axis and rotate the output shaft. Since the hydraulic torque wrench having this structure is provided with a pair of raised portions and sliding members, it reaches the contact position once per half rotation of the cylinder with respect to the output shaft. Accordingly, two impact torques are generated in the output shaft by one rotation of the cylinder.

  On the other hand, a hydraulic torque wrench has been proposed in which the generated torque is increased by generating an impact torque once on the output shaft by one rotation of the cylinder. Examples of such a hydraulic torque wrench include those described in Japanese Patent Application Laid-Open No. 64-45582 (Patent Document 1) and Japanese Patent Application Laid-Open No. 5-253858 (Patent Document 2).

  Patent Document 1 discloses that a cam member and an output shaft are each formed with an oil passage, and a cam member at one of two positions where a pair of raised portions and a sliding member meet during one rotation of the cylinder. The oil passages of the output shaft communicate with each other and do not communicate with each other at the other position. As a result, high pressure is not formed at the position where the oil passages are communicated, and driving force is transmitted only at the other matching position. As a result, one torque is generated by one rotation of the cylinder.

The thing of patent document 2 is provided with a pair of flat part which protruded in the position which makes | forms 180 degrees in a radial direction from a cam member. The pair of sliding members have engaging portions protruding inward in the radial direction, the engaging portions are pressed from the inside by the flat portion of the cam member, protrude in the radial direction, and come into contact with the raised portion of the cylinder. To the position to get. The engaging portion is provided with a notch in one of the pair, and the engaging portion of the sliding member has one of the pair having a larger width and the other having a smaller width. Accordingly, the smaller engaging portion is not pressed from the flat portion because it passes through the notch, and the larger engaging portion is operated so as to be pressed from the flat portion because it does not pass through the notch. As a result, the sliding member protrudes only at one of the two matching positions of the flat portion and the sliding member during one rotation of the cylinder to form a high pressure. As a result, one torque is generated by one rotation of the cylinder. To do.
JP-A 64-45582 JP-A-5-253858

  In the structure in which the impact torque is generated twice on the output shaft by one rotation of the cylinder, it is difficult to efficiently output a large torque as a result of the energy of the drive source being dispersed over many times of torque generation.

  On the other hand, when the structure described in the above-mentioned patent document is used in order to generate a shocking torque once in one rotation of the cylinder, there are the following problems. That is, in the structure described in Patent Document 1, it is necessary to form an oil passage in the cam member and the output shaft. In the structure described in Patent Document 2, the sliding member having the smaller engagement portion is larger. Since the sliding member having the engagement portion performs the projecting operation only once during the projecting operation twice, the operation becomes irregular. Also, in any structure, the sliding member in contact with the cam member performs a wasteful projecting operation even at a timing when no torque is generated, and accordingly, wear of the sliding member and its sliding surface is accelerated, and energy is increased. It will cause loss.

  Accordingly, an object of the present invention is to provide a hydraulic torque wrench that can output torque efficiently with a simple structure as compared with a conventional device.

  In order to achieve the above object, the present invention has an output shaft that applies torque to an object, a front wall that rotatably supports the output shaft and penetrates it so as to protrude forward, and a drive input section connected to the rear portion. A rear wall and a side wall located between them, forming a fluid-tight chamber containing hydraulic oil therein, a cylinder capable of rotating about the same rotation axis as the output shaft, and the cylinder in the liquid-tight chamber A plurality of sliding members held slidably in the radial direction by an output shaft; and a cam member connected to the rear wall so as to rotate together with the cylinder, wherein the output shaft is supported by the front wall. And a shaft base portion that protrudes forward and a shaft base portion that is positioned in the liquid-tight chamber, and a rotational driving force is applied to the shaft base portion on the inner surface of the side wall of the cylinder based on contact with the sliding member. A plurality of ridges are formed in the circumferential direction to exert The shaft base is formed with a receiving hole extending along the rotation axis, and a plurality of guide grooves that are arranged at intervals corresponding to the raised portions and extend in the axial direction and open on the outer peripheral surface. The moving member is slidably received in each guide groove of the shaft base so as to be slidable in the radial direction, and an outer portion extending along the guide groove and a portion located radially inward from the outer portion and partially An inner portion provided so as to protrude into the receiving hole, and the plurality of sliding members include the inner portion at different locations in the axial direction, and the shaft base portion includes the guide groove. A bottom wall is provided on the radially inner side, and a through hole is formed in the bottom wall for guiding the inner portion in the radial direction. The cam member has a flat portion positioned in the accommodation hole in the axial direction. A plurality of different portions are provided, and the flat portion is provided on the rotating shaft. The sliding members extend in different radial directions from each other and act on the sliding member simultaneously every time the cam member makes one rotation, so that the sliding member reaches an operating position where it can contact the raised portion. A hydraulic torque wrench characterized by being arranged corresponding to the above (Invention 1).

  The invention 1 is established on the basis of the following structure 1, and the invention 1 and the structure 1 can further adopt the structure 2 or less as related structures.

  [Structure 1] The hydraulic torque wrench has an output shaft for applying torque to an object, and the output shaft is rotatably supported so as to protrude forward, and a drive input portion is connected to the rear portion to operate internally. A cylinder that forms a fluid-tight chamber containing oil; a sliding member that is slidable in the radial direction by the output shaft in the liquid-tight chamber; and a cam member that is connected to receive a rotational force from the cylinder; The output shaft includes a shaft tip portion supported by the cylinder and protruding forward, and a shaft base portion located in the liquid-tight chamber, and an inner surface of the side wall of the cylinder includes the sliding member. A plurality of raised portions are formed in the circumferential direction for exerting a rotational driving force on the shaft base portion based on the contact of the shaft, and the shaft base portion includes a receiving hole extending along the rotation axis, and an outer periphery extending in the axial direction. A guide groove that is open on the surface. The sliding member is slidably received in each guide groove of the shaft base portion in the radial direction, and a part of the sliding member protrudes into the receiving hole. A flat portion located in the hole is provided, and the flat portion acts on the sliding member and corresponds to the sliding member so as to reach the operating position where the sliding member can contact the raised portion. Are arranged.

  [Structure 2] In the invention 1 or structure 1, the sliding member incorporates an accumulator for buffering a hydraulic pressure fluctuation in the liquid tight chamber, and the accumulator extends in a direction along the rotation axis and is at one end. A storage chamber having a liquid passage hole and a piston slidably accommodated in the storage chamber and biased toward the liquid passage hole can be provided.

  [Structure 3] In the invention 1 or the structure 1 or 2, the raised portion of the cylinder is set so that the sliding member passes through the raised portion by a minute displacement when in contact with the sliding member. A rotational driving force to the shaft base portion based on contact between the raised portion and the sliding member may be formed by contact pressure from the contact to passage.

[Structure 4] In the structure 3, the cam member includes a disk portion that is arranged side by side in the axial direction with respect to the flat portion and has a peripheral surface along an inner peripheral surface of the accommodation hole in the shaft base portion, and the shaft A release hole is formed in the base so as to face the disk part at a position between each of the plurality of guide grooves and to penetrate the shaft base part in the radial direction. As a result, a communication part is formed,
The communication portion is located at a position facing the guide groove when the flat portion is in a rotational position that brings the sliding member to the operating position, and blocks communication between the guide groove and the release hole; When the flat portion passes through the rotation position, the flat portion may be formed in a size that allows both to communicate across the guide groove and the release hole.

  [Structure 6] In the invention 1 or structure 1, an oil containing space is formed between the cylinder and the shaft base portion, and the shaft base portion has a seal projection at a circumferential position different from the sliding member. The cylinder is further provided with a sealing protrusion for contacting the sealing protrusion when the sliding member contacts the raised portion and partitioning the oil containing space into divided spaces. The rotational driving force to the shaft base portion based on the contact between the raised portion and the sliding member can be formed by the pressure generated in the divided space under the seal by the contact.

  According to the present invention, a hydraulic torque wrench having the following effects can be provided. That is, in this torque wrench, the sliding member is slidably held in each of the plurality of guide grooves of the output shaft, and the flat portion of the cam member that rotates within the accommodation hole of the output shaft serves as a cylinder for the sliding member. An operating position that can contact the raised portion of the inner surface is reached, and the raised portion exerts a rotational driving force on the output shaft based on the contact. The plurality of sliding members include inner portions that can protrude into the receiving holes at different locations in the axial direction, and the cam member includes a plurality of the flat portions at different locations in the axial direction. The portion is arranged corresponding to each sliding member so as to simultaneously act on the sliding member every time the cam member makes one rotation and bring the sliding member to the operating position. As described above, the flat portions located at the positions corresponding to the axial direction and the rotation direction with respect to the plurality of sliding members act on the sliding member for each rotation of the cam member. There is no protruding operation of the sliding member at the timing when it does not occur, and torque can be output efficiently with a simple structure.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. The same or similar parts in the drawings may be denoted by the same reference numerals and description thereof may be omitted.

[First Embodiment]
FIG. 1 shows a first embodiment of a hydraulic torque wrench according to the present invention, and FIG. 2 is a partially cutaway view of the casing. This hydraulic torque wrench includes a body 1 and a handle 2, and the body 1 includes a drive motor 3 at a rear portion and a transmission device 4 at a front portion, and an output shaft 10 projects from a front end. The handle 2 is sized to be held with one hand, and a motor-operated on / off switch 5 is provided on the front side. As the drive motor, a motor provided with an appropriate drive source such as an electric motor or an air motor can be used.

  3 shows a longitudinal section of the transmission device 4 of FIG. 1, and FIG. 4 shows a section taken along line IV-IV of FIG. The transmission device 4 includes a cylinder 20 in which an output shaft 10 that gives torque to an object protrudes forward, and a rear portion of the cylinder is connected to a rotating shaft 3 a of the drive motor 3. The cylinder 20 includes a front wall 21 through which the output shaft 10 is rotatably supported and protruded forward, a rear member 22 to which the rotary shaft 3a is connected rearward, and a side wall 23 positioned therebetween. I have.

  In this embodiment, the front wall 21 and the side wall 23 are integrally formed, and the rear member 22 serves as a rear wall that closes the opening at the rear end of the side wall 23. The rear member 22 includes a cylindrical wall 26, a flange 27 extending radially outward from the front end of the cylindrical wall, and a connecting shaft portion 28 extending rearward from the rear end of the cylindrical wall 26, In a state where the flange 27 is fitted in the opening of the side wall 23, the holding ring 29 is screwed and fixed to the side wall 23 from the rear.

  Seal rings 21a and 27a are arranged between the front wall 21 and the main shaft 10 and between the flange 27 and the side wall 23. A liquid tight chamber 24 is formed inside the cylinder 20, and hydraulic oil is accommodated therein. Yes.

  The output shaft 10 includes a shaft tip portion 11 that is supported by the front wall 21 of the cylinder 20 and protrudes forward, and a shaft base portion 12 that is positioned in the liquid-tight chamber 24, and the shaft base portion 12 has a rear end portion as a rear member. It is rotatably supported inside the 22 cylindrical walls 26. The shaft base 12 includes an enclosure wall 15 formed therein with a housing hole 14 extending in the axial direction. The enclosure wall extends in the axial direction and is deepened in the radial direction from the peripheral surface, and extends in parallel to each other. A pair of guide grooves 16 provided with A pair of through holes 17 are formed in the bottom wall 15 a of the guide groove 16 in the surrounding wall 15.

  In the liquid tight chamber 24, the sliding member 40 is held in the guide groove 16 of the shaft base 12 so as to be slidable in the radial direction. The sliding member 40 includes an outer portion 41 extending over the axial length of the guide groove 16 and an inner portion 42 formed of a roller (small piece) in contact with the radially inner side of the outer portion 41. The twelve guide grooves 16 are slidably held in the radial direction. The outer portion 41 has a side wall parallel to the side wall of the guide groove 16 and is fitted into the guide groove 16 almost closely. The inner portion 42 is inserted into the aforementioned through-hole 17 and can take a position protruding from the through-hole 17 into the accommodation hole 14 and a position retracted from the accommodation hole 14 depending on the sliding position. The pair of sliding members 40 includes inner portions 42 at different locations in the axial direction. As in this example, when the inner portion 42 is a roller and its axis is parallel to the axis of the cam member 50, the cam member 50 is brought into point contact and the frictional resistance is reduced. From this viewpoint, the inner portion 42 may be a sphere. Or if it is a member with small frictional resistance, the inner part 42 can also be made into the pin which has the cross-sectional shape corresponding to the through-hole 17. FIG.

  As shown in FIG. 4, the side wall 23 of the cylinder 20 has a substantially circular cross-sectional shape on the inner peripheral surface, and a pair of gently raised ridges 31 are provided at opposing positions. Each extend in the axial direction. As shown in FIG. 4, these portions are arranged so that the pair of raised portions 31 and the pair of sliding members 40 reach the opposite positions at the same time in the rotational position of the cylinder 20. The raised portion 31 is in contact with the sliding member 40 and applies a pushing force in the radial direction.

  Further, the cam member 50 shown in FIGS. 5 and 6 is accommodated in the accommodation hole 14 of the shaft base 12. 5A is a front view, FIG. 5B is a plan view, FIG. 5C is a c view of FIG. 5A, FIG. 5D is a d view of FIG. 5B, and FIG. (F) is a sectional view taken along line ff of (b), and FIG. 6 is a perspective view.

  The cam member 50 has a front end portion 51, a central portion 52, and a rear end portion 53 having a disk shape having an outer diameter close to the inner diameter of the accommodation hole 14, and between the front end portion 51 and the central portion 52 and in the center. Flat portions 54 and 55 are respectively provided between the portion 52 and the rear end portion 53. The two flat portions 54 and 55 extend in opposite radial directions at positions corresponding to the inner portion 42 of the sliding member in the axial direction. Each of the disc-shaped front end 51, center 52 and rear end 53 has one notch 51a, 52a in which a part of the periphery is flattened, and a pair of notches 53a at positions facing each other. Is provided, and the circulation of the hydraulic oil and the equalization of the pressure in the accommodation hole 14 are achieved. On the rear end surface of the rear end portion 53 of the cam member 50, a convex portion 53c extending in the radial direction is provided. On the other hand, a recess 22a is provided on the inner end surface of the rear wall 22 of the cylinder 20 corresponding to the protrusion 53c (FIG. 3), and the output shaft 10 is fitted by the fitting of the protrusion 53c and the recess 22a. , And rotates with the cylinder 20.

  FIG. 7 shows the positional relationship between the cam member 50 and the sliding member 40 in an exploded state of the members. 7A shows a state in which the sliding member 40 is pushed out by the flat portions 54 and 55 of the cam member 50, and FIG. 7B shows a state in which the sliding member 40 deviates from the action of the flat portions 54 and 55 of the cam member 50. Each indicates a state of retreating. The sliding member 40 is in a position protruding from the guide groove 16 when the inner portion 42 of the cam member 50 is in contact with the tip end portions of the flat portions 54 and 55, and the flat portions 54 and 55 of the sliding member 40 are rotated along with the rotation of the cam member 50. As the contact portion of the inner portion 42 moves to the flat surface, the guide groove 16 can be immersed. FIG. 4 shows a state in which the flat portions 54 and 55 project the sliding member 40 from the guide groove 16.

  Further, as shown in FIG. 8, a pair of release holes 19 are formed in the shaft base portion 12 of the output shaft 10 so as to penetrate outward from the housing holes 14 at positions opposed to each other in the radial direction. 8A is a cross-sectional view taken along the line VIII-VIII in FIG. 3, and FIG. 8B is an enlarged view of the vicinity of the inner end of the release hole 19. The release hole 19 is provided at a position corresponding to the rear end portion 53 of the cam member 50 as indicated by a broken line in FIG. On the other hand, in the rear end portion 53 of the cam member 50, a pair of communication portions 53b provided in a notch shape at positions different from the notch portions 53a are formed at positions opposed in the radial direction. As will be described later, the cutout portion 53a and the communication portion 53b cause the through hole 17 and the release hole 19 of the guide hole 16 to communicate with each other through the accommodation hole 14 depending on the rotational position of the cam member 50 (FIG. 9). It functions to close (FIG. 8).

  Next, the first embodiment will be further described with reference to FIG. FIG. 10 shows how the cylinders 20 and the like rotate according to phase when the hydraulic torque wrench is in use. Assuming that the phase (A) in the drawing of the cylinder 20 that rotates clockwise is the initial state (0 °), the rotation angle of the cylinder 20 in each phase is as follows: phase (B): 55 °, phase (C): 60 °, phase (D): 61 °, phase (E): 90 °, phase (F): 180 °, phase (G): 270 °, phase (H): 315 °, and 360 ° rotation. To return to phase (A).

  In the phase (A), the sliding member 40 is extruded radially outward by the flat portions 54 and 55 of the cam member 50. In this state, as shown in FIG. 8, the communication portion 53 b formed at the rear end portion 53 of the cam member 50 is in a position facing the release hole 19. As is apparent from the shape of the cam member 50 shown in FIGS. 5 and 6, the communication portion 53 b communicates with the voids around the flat portions 54 and 55 and the notches 51 a and 52 a in the accommodation hole 14. Therefore, the hydraulic oil in the accommodation hole 14 is in a circulation state in the outer portion of the surrounding wall 15 in the liquid tight chamber 24 through the communication portion 53 b and the release hole 19.

  In phase (B), the raised portion 31 has just started to contact the sliding member 40. FIG. 4 described above shows this state, and as shown in the figure, the communication portion 53b is located away from the release hole 19 (indicated by the alternate long and short dash line). As a result, the hydraulic oil in the accommodation hole 14 cannot be distributed through the release hole 19. In addition, as shown in FIG. 4, the sliding member 40 located in the upper part of the drawing is slightly inclined due to the contact force of the raised portion 31, and the outer side portion P <b> 1 on the right side surface becomes the outer edge of the guide groove 16. The inner end P2 on the left side is in contact with the inner edge of the guide groove 16. The sliding member located in the lower part of the figure is similarly inclined. Therefore, in the phase (B), the flat portions 54 and 55 are disengaged from the sliding member 40, but a seal is formed by the contact between the sliding member 40 and the guide groove 16, and the hydraulic oil inside the guide groove 16 is It will be sealed and it will be in the operation state where the protruding state of sliding member 40 was held. The sealed region is indicated by hatching in FIG.

  As the raised portion 31 rotates to the phase (C) from this state, the rotational driving force to the shaft base portion 12 is transmitted by the contact pressure between the raised portion 31 and the sliding member 40. The sliding member 40 moves slightly into the guide groove 16 in accordance with the compressive deformation of the hydraulic oil and a slight leakage at the contact portion. The output state due to this transmission occurs instantaneously, and pulse torque is generated on the output shaft 10.

  The phase (D) is a state where the cam member 50 is slightly rotated from the phase (C), and this state is shown in FIG. FIG. 9A shows the state of the phase (D) in the same cross section as FIG. 8, and FIG. 9B is an enlarged view of the vicinity of the inner end of the release hole 19. In this state, the communication member 53 b of the cam member 50 starts to communicate with the edge of the release hole 19. Accordingly, the hydraulic oil in the accommodation hole 14 can flow out through the release hole 19 and between the shaft base 12 and the cylinder 20 in the liquid tight chamber 24. As a result, the pressing force from the raised portion 31 acts on the sliding member 40, so that the sliding member 40 is pushed into the retracted position in the guide groove 16 with the outflow of the hydraulic oil.

  In the phase (E), the raised portion 31 moves on the sliding member while the sliding member 40 is pushed in.

  In the phase (F), the flat part 54 located at the front and the flat part 55 located at the rear reach the position of 180 ° with respect to the inner portions 42 and 42 of the front and rear sliding members 40, respectively. The sliding member 40 holds the retracted position.

  In the phase (G), the protruding portion 31 reaches the position corresponding to the sliding member 40 again. However, since the sliding member 40 is in the retracted position, the protruding portion 31 exerts a rotational force on the sliding member 40. Absent.

  In the phase (H), the flat portions 54 and 55 push out the sliding member 40 again. In this extrusion process, the notch 53a is moved from the position shown in FIG. 8 (upper left and lower right) to the lower left and upper right, and a part thereof is at a position facing the release hole 19. Accordingly, the hydraulic oil outside the surrounding wall 15 in the liquid tight chamber 24 can flow into the through hole 17 and the guide groove 16 from the release hole 19 through the notch 53 a and the accommodation hole 14. Then, when the pushing force from the flat portions 54 and 55 acts on the sliding member 40, the sliding member 40 forms a negative pressure inside the guide groove 16 and the guide groove with the inflow of the hydraulic oil. 16 is extruded outward.

  Thus, in this embodiment, when the cylinder 20 makes one rotation with respect to the sliding member 40 from the initial output state, the cam member 50 makes one rotation to bring the sliding member 40 into an operating state. Thus, the next output state is obtained. This is because the raised portions are formed at two opposite positions in the cylinder, the pair of sliding members 40 are provided with inner portions 42 at different positions in the axial direction, and the cam member is separated from the rotation axis. A pair of flat portions 54 and 55 extending in a direction of 180 ° with each other are provided, and the pair of flat portions simultaneously act on the sliding member 40 each time the cam member makes one rotation, and the sliding portion It is obtained by being arranged corresponding to each sliding member 40 so as to bring the member to the operating position.

  Next, as shown in FIG. 2, since the accumulator 60 is provided in the sliding member 40, this is demonstrated. FIG. 11 is a longitudinal sectional view showing only the accumulator portion, where (a) shows a state in which hydraulic oil is released and (b) shows an inflow state of hydraulic oil. The accumulator 60 is provided in a hole 44 that is closed at one end in the axial direction of the output shaft 10 in the outer portion 41 of the sliding member 40. A compression coil spring 61 is accommodated in the hole 44, and a plug body 62 is slidably fitted on the opening side thereof. A seal ring 63 is attached to the outer peripheral surface of the plug body 62, and between the inner surface of the outer portion 41. A seal is formed. Air is sealed in the hole 44 by this seal. There is a slight gap between the front end of the sliding member 40 and the front wall 21 of the cylinder 20, and the gap hardly affects the sudden fluctuation of the pressure in the liquid tight chamber during torque transmission, and The operating oil is circulated slowly to such an extent that a gradual pressure fluctuation due to a change in ambient temperature or the like can be absorbed over time.

  In this structure, when the pressure in the liquid tight chamber 24 is normal, the plug body 62 is positioned forward (left in the figure) in a state where the force of the spring 61 is received. When the pressure in the liquid tight chamber 24 increases due to heat generated by the operation of the torque wrench or an increase in ambient temperature, the plug body 62 resists the force of the spring 61 and the air in the hole 44 due to the increase in pressure received on the front end surface. Slowly moving backwards while compressing. As a result, the hydraulic oil storage volume is increased, and as a result, the pressure in the liquid tight chamber 24 is compensated and normal operation is ensured. In this example, the accumulator is provided in the outer portion 42 of the sliding member 40, and the outer portion has a sufficient volume to provide a hole for the accumulator, so that the function of the transmission device 4 is impaired. In addition, the torque wrench has the advantage that it can be installed without causing an increase in the external dimensions of the torque wrench or very little.

[Second Embodiment]
Next, a second embodiment of the hydraulic torque wrench according to the present invention will be described. 12 is a front view showing a part of the hydraulic torque wrench, FIG. 13 is a longitudinal section showing the transmission device 104 together with a part of the casing, and FIG. 14 is a section taken along line XIV-XIV in FIG. ing. As in the case of the first embodiment, this hydraulic torque wrench includes a body 101, a handle 102, a drive motor 103, a transmission device 104, and an on / off switch 105, and projects an output shaft 110 from the front end. Yes.

  In this embodiment, the following structure is the same as that of the first embodiment. That is, the transmission device 104 includes a cylinder 120. The cylinder 120 includes a front wall 121, a rear member 122, and a side wall 123. The rear member 122 includes a cylindrical wall 126, a flange 127, a connecting shaft portion 128, And a retaining ring 129. In addition, seal rings 121a and 127a are arranged, and the inside of the cylinder 120 forms a liquid tight chamber 124 containing hydraulic oil. The output shaft 110 includes a shaft tip portion 111 and a shaft base portion 112. The shaft base portion 112 is rotatably supported at the rear end portion inside the cylindrical wall 126 of the rear member 122, and the accommodation hole 114 is formed inside. A surrounding wall 115 is formed, and a pair of guide grooves 116 having side walls extending in parallel to each other are formed in the surrounding wall. In addition, a sliding member 140 including an outer portion 141 and an inner portion 142 is slidably held in the guide groove 116.

  In this embodiment, unlike the first embodiment, 123 provided with side walls extending in parallel with the side walls of the cylinder 120 is raised lower than the raised portions 131 at opposed positions in a direction orthogonal to the pair of raised portions 131. Sealing convex portions 132 are provided, and the raised portions 131 and the sealing convex portions 132 each extend in the axial direction. The shaft base 112 is formed with a seal projection 118 corresponding to the seal projection 132. As shown in FIG. 14, these portions are arranged so that the raised portion 131 and the sliding member 140, the sealing convex portion 132, and the sealing projection 118 reach the opposing positions at the same time in the rotational position of the cylinder 120. At this position, the raised portion 131 is in contact with the sliding member 140 to apply a pushing force in the radial direction, and the sealing convex portion 132 is substantially in contact with or slightly pressed against the sealing projection 118. A cam member 150 shown in FIG. 15 is accommodated in the accommodation hole 114 of the shaft base 112. FIG. 15 shows the positional relationship between the cam member 150 and the sliding member 140 in an exploded state. FIG. 15A shows that the sliding member 140 is pushed out by the flat portions 154 and 155 of the cam member 150. FIG. 15B shows a state where the sliding member 140 is retracted from the action of the flat portions 154 and 155 of the cam member 150. The cam member 150 has the same structure as that of the first embodiment, and has a disk-shaped front end portion 151, a central portion 152 and a rear end portion 153 having outer diameters close to the inner diameter of the accommodation hole 114, and these Are provided with flat portions 154 and 155. The rear end surface of the rear end 153 is provided with a convex portion 153c extending in the radial direction, and the inner end surface of the rear wall 122 of the cylinder 120 is provided with a concave portion 122a corresponding to the convex portion 153c (see FIG. 13) The output shaft 110 rotates together with the cylinder 120 by the fitting of the convex portion 153c and the concave portion 122a.

  In the sliding member 140, the outer portion 141 has a side wall parallel to the side wall of the guide groove 116, and the inner portion 142 is radially inward from the outer portion 141. It is integrally formed as an extended protrusion (small piece). The pair of sliding members 140 includes inner portions 142 at different locations in the axial direction. As shown in FIG. 15A, the sliding member 140 is in a position protruding from a guide groove (not shown) when in contact with the tip portions of the flat portions 154 and 155, and as the cam member 150 rotates. Then, when the flat portions 154 and 155 are disengaged from the tip portions, as shown in FIG.

  Next, the second embodiment will be further described with reference to FIG. FIG. 16 shows how the cylinder 120 and the like rotate in accordance with the phase when the hydraulic torque wrench is in use. Assuming that the phase (A) in the drawing of the cylinder 120 rotating clockwise is the initial state (0 °), the rotation angle of the cylinder 120 in each phase is as follows: phase (B): 90 °, phase (C): 180 °, phase (D): 270 °.

  In the phase (A), the sliding member 140 is at a position deviated from the flat portion 154 of the cam member 150 and is retracted into the guide groove 116. In this state, the sealing convex portion 132 of the cylinder 120 is at a position corresponding to the sliding member 140, but no pressure is generated to transmit the rotational force in the liquid tight chamber.

  In phase (B), the flat portions 154 and 155 each contact the pair of inner portions 142 of the sliding member, and push the sliding member 140 to the operating position at the tip. As a result, the raised portion 131 comes into contact with the sliding member 140, and at the same time, the sealing convex portion 132 comes into contact with the sealing projection 118.

  In the phase (C), the sealing convex portion 132 again comes to a position corresponding to the sliding member 140. However, since the sliding member 140 is in the retracted position, the pressure that transmits the rotational force to the liquid tight chamber is not Does not occur.

  In the phase (D), the sealing projection 132 is in contact with the sealing projection 118, but the sliding member 140 is in the retracted position, so that no pressure is generated to transmit the rotational force in the liquid tight chamber.

  Details of the phase (B) state are shown in FIG. Since the cylinder 120 rotates clockwise in the drawing, when the upper sliding member 140 is viewed, the sliding member 140 is inclined clockwise by the pressing force from the raised portion 131 and the right end surface of the outer portion 141 is inclined. The right side opening edge of the guide groove 116 is contacted and pressed to perform a sealing action (a contact point is indicated by P3). An oil storage space is formed between the cylinder 120 and the shaft base 112. In the phase (B), the oil storage space includes the raised portion 131, the sliding member 140, the sealing convex portion 132, and the sealing protrusion 118, respectively. Is partitioned into divided spaces. The shape of the oil storage space is determined by rotating the cylinder 120 so that the divided space on the upstream side of the rotation is made high pressure and the divided space on the downstream side is made low pressure by the ridge 131. In FIG. 16B, the high-pressure portion is shown with spots. Note that the left end surface of the sliding member 140 is such that the inner portion 142 contacts the guide groove 116 at the point P0. As a result, the outer portion 141 does not contact the guide groove 116, and a sealing action does not occur. As a result, the high pressure portion passes through the left side of the sliding member 140 and extends into the accommodation hole 114. Therefore, the contact pressure with the raised portion 131 tries to push the sliding member 140 into the guide groove 116, but the sliding member is in an operating state in which the protruding position is maintained by the action of the high pressure portion.

  In this way, the rotational driving force to the shaft base 112 based on the contact between the raised portion 131 and the sliding member 140 is transmitted by the pressing force accompanying the contact and the pressure in the divided space generated under the seal. This output state occurs instantaneously in the phase (B), and pulse torque is generated on the output shaft 110. Then, the cylinder 120 further rotates and shifts to the phase (C).

As described above, in this embodiment, when the cylinder 120 makes one rotation with respect to the sliding member 140 from the initial output state, the cam member 150 makes one rotation to bring the sliding member 140 into an operating state. Thus, the next output state is obtained. As in the first embodiment, the raised portions are formed at two opposing positions in the cylinder, and the pair of sliding members 140 are provided with inner portions 142 at different positions in the axial direction. The cam member is provided with a pair of flat portions 154 and 155 extending in the direction of 180 ° from the rotation axis, and the pair of flat portions is a sliding member simultaneously every time the cam member makes one rotation. It is obtained by being arranged corresponding to each sliding member 140 so as to act on 140 and bring the sliding member to the operating position.
[Other Embodiments]
The present invention is not limited to the above embodiment, and various modifications can be involved. FIG. 18 shows a modification of the second embodiment. In the sliding member 140 according to the second embodiment, the inner portion 142 is integrally formed as a protrusion extending radially inward from the outer portion 141, but here, the sliding member 140 ′ is the first member. The sliding member 40 according to the embodiment has substantially the same configuration, and includes an outer portion 141 ′ extending over the axial length of the guide groove and a roller (small piece) in contact with the radially inner side of the outer portion 41. An inner portion 142 is provided. 18 shows the same parts as those in the first embodiment with the same numbers, and FIG. 18A shows a state in which the sliding member 140 ′ is pushed out by the flat portions 154 and 155 of the cam member 150, FIG. ) Shows a state in which the sliding member 140 ′ is retracted from the action of the flat portions 154 and 155 of the cam member 150, respectively. In this example, the outer portion 141 ′ has a notch 143 formed at a radially inner corner with respect to a block having the same shape as the outer portion 141 in the first embodiment. The notches 143 are provided at positions corresponding to different ones of the flat portions 154 and 155 of the cam member 150 in the pair of outer portions 141 ′. Since the outer portion 141 ′ has this configuration, in the state shown in FIG. 19, that is, in the same phase as the phase (B) in the second embodiment (FIG. 17), the outer portion 141 ′ is rotated by the cylinder 120 turning to the right. The right end surface is brought into contact with the right opening edge of the guide groove 116 for sealing (a contact point is indicated by P4). When the cylinder 120 rotates clockwise in this state, the divided space partitioned by the facing of the raised portion 131 and the sliding member 140, the sealing convex portion 132, and the sealing projection 118 becomes high pressure. On the other hand, even if the left end surface of the sliding member 140 is in contact with the side wall of the guide groove 116, communication through the notch 143 is ensured. As a result, the high pressure portion passes through the left side of the sliding member 140 and extends into the accommodation hole 114. FIG. 19 shows the high-pressure portion by cross hatching. Thus, when the divided space is formed, the communication through the notch 143 is ensured. As a result, the pressure in the high-pressure portion is made uniform, and smooth rotation without unevenness is obtained. The notches 143 are provided on both the left and right sides of the single outer portion 141 ′ so as to act on both forward and reverse rotations of the cylinder 120.

  As another modification, the number of sliding members can be three or more at regular intervals around the rotation axis of the output shaft, in addition to a pair as in the above embodiment. In this case, a seal projection, a seal projection, a flat portion of the cam member, a communication hole, and the like are arranged corresponding to the arrangement of the sliding member.

  Further, the accumulator and torque setting structure shown in the first embodiment can be applied to the second embodiment.

  Furthermore, by interposing a transmission gear train between the cylinder or the rear member and the cam member, the cylinder brings the raised portion into contact with the sliding member and the cam member is in the position where the sliding member is in the operating state. When the cylinder rotates more than one rotation with respect to the sliding body, the speed change operation can be performed so that the cam member reaches the position where the sliding body is activated. As a result, the output cycle is obtained when the cylinder rotates more than one rotation, and the energy at each output increases as the output frequency with respect to the rotation of the input shaft decreases. As a result, a higher torque can be generated, or the apparatus can be further miniaturized with the same torque.

1 is a front view showing a hydraulic torque wrench according to a first embodiment of the present invention. It is a front view which notches and shows a part of hydraulic type torque wrench of FIG. It is a longitudinal front view of the transmission device of the hydraulic torque wrench of FIG. It is sectional drawing which follows the IV-IV line of FIG. It is a figure which shows the cam member in the transmission of FIG. 3, (a) is a front view, (b) is a top view, (c) is c view of (a), (d) is d view of (b). FIG. 4E is a sectional view taken along line ee of a, and FIG. 5F is a sectional view taken along line ff of FIG. FIG. 6 is a perspective view of the cam member shown in FIG. 5. It is explanatory drawing about an action | operation with the cam member and sliding member in the transmission of FIG. (a) is sectional drawing which follows the VIII-VIII line of FIG. 3, (b) is a figure which expands and shows a part of (a). (a) is a figure which shows the phase from which cylinder rotation differs about the same cross section as FIG. 8, (b) is a figure which expands and shows a part of (a). FIG. 2 is an operation explanatory diagram of the hydraulic torque wrench of FIG. 1. It is the longitudinal cross-sectional view which shows the accumulator part in the hydraulic torque wrench of FIG. 1 in a different state to (a) and (b). It is a front view which shows the hydraulic type torque wrench which concerns on 2nd Embodiment of this invention in a partial cross section. FIG. 13 is a longitudinal front view of the transmission device of the hydraulic torque wrench of FIG. 12. It is sectional drawing which follows the XIV-XIV line of the transmission of FIG. It is explanatory drawing which shows a different state about the action | operation of the cam member and sliding member in the transmission of FIG. 13, in (a) and (b). It is action | operation explanatory drawing of the hydraulic torque wrench of FIG. It is sectional drawing which shows the cross section of the same location as FIG. 14 in a different operation | movement phase. It is a perspective view which shows the sliding member and cam member in the modification of 2nd Embodiment of this invention. It is sectional drawing of the same location as FIG. 17 shown about the modification shown in FIG.

Explanation of symbols

10, 110 Output shaft 11, 111 Shaft tip portion 12, 112 Shaft base portion 14, 114 Housing hole 15, 115 Surrounding wall 16, 116 Guide groove 18, 118 Seal projection 19 Release hole 20, 120 Cylinder 21, 121 Front wall 22 122 Rear member 23, 123 Side wall 24, 124 Liquid tight chamber 31, 131 Raised portion 132 Sealing convex portion 40, 140, 140 'Sliding member 50, 150 Cam member 60 Accumulator

Claims (4)

An output shaft for applying torque to the object;
The output shaft is provided with a front wall that is rotatably supported and penetrated so as to protrude forward, a rear wall that is connected to the rear portion of the drive input portion, and a side wall positioned therebetween, and contains hydraulic oil therein. A cylinder capable of rotating around the same rotation axis as the output shaft,
A plurality of sliding members held slidable in the radial direction by the output shaft in the liquid tight chamber;
A cam member connected to the rear wall to rotate with the cylinder;
The output shaft includes a shaft tip portion that is supported by the front wall and protrudes forward, and a shaft base portion that is located in the liquid-tight chamber,
A plurality of raised portions in the circumferential direction are formed on the inner surface of the side wall of the cylinder to exert a rotational driving force on the shaft base portion based on contact with the sliding member,
The shaft base is formed with a receiving hole extending along the rotational axis, and a plurality of guide grooves that are arranged at intervals corresponding to the raised portions and each extend in the axial direction and open to the outer peripheral surface.
The sliding member is slidably received in each guide groove of the shaft base portion in a radial direction, and has an outer portion extending along the guide groove, and a portion positioned radially inward from the outer portion. An inner portion provided so as to protrude into the receiving hole, and the plurality of sliding members include the inner portions at different locations in the axial direction,
The shaft base includes a bottom wall on the radially inner side of the guide groove, and a through hole is formed on the bottom wall to guide the inner portion in the radial direction.
The cam member includes a plurality of flat portions located in the receiving hole at different positions in the axial direction, the flat portions extend in mutually different radial directions from the rotation axis, and the cam member makes one rotation. Each hydraulic member is arranged corresponding to each sliding member so as to act on the sliding member at the same time and reach the operating position where the sliding member can come into contact with the raised portion. A wrench.   2. The hydraulic torque wrench according to claim 1, wherein an inner portion of the sliding member is formed by a projecting piece continuously extending from the outer portion. The sliding member includes an outer portion extending along the guide groove, and an inner portion protruding radially inward from the outer portion, and the inner portion is formed by a small piece separate from the outer portion. The shaft base portion includes a bottom wall on the radially inner side of the guide groove, and a through hole that guides the inner portion in the radial direction is formed on the bottom wall. Hydraulic torque wrench. The sliding member incorporates an accumulator for buffering hydraulic pressure fluctuations in the liquid tight chamber, and the accumulator extends in a direction along the rotation axis and has a reservoir chamber having a liquid passage hole at one end thereof, The hydraulic torque wrench according to any one of claims 1 to 3, further comprising a piston slidably accommodated in the chamber and biased toward the liquid passage hole.

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