Oil pulse unit and work machine

Abstract

To provide an oil pulse unit and a work machine having large fastening torque.SOLUTION: In an oil pulse unit 40, a liner 41 includes third protrusions 54 and 55 configured to protrude inside in a radial direction in an inner peripheral part 66 and a slide 61 and to be able to abut against blades 43 and 44. The third protrusions 54 and 55 protrude from a substantially circular-arc part 61a of the slide 61 inside in the radial direction. The oil pulse unit 40 is configured such that when the liner 41 rotates against a shaft 42, the third protrusions 54 and 55 abut against the blades 43 and 44 to transmit a striking force of a rotation direction from the third protrusions 54 and 55 to the blades 43 and 44, and roughly simultaneously first protrusions 52 and 53 and second protrusions 56 and 57 face each other to add oil pressure of a rotation direction to the blades 43 and 44.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an oil pulse unit and a work machine configured to perform a screw driving operation. [Background technology]

[0002] Figure 16 and other figures of Patent Document 1 disclose an impact tool as a work machine configured such that a raised portion 131 that can abut radially against a sliding member 140 is provided on the inner periphery of a cylinder 120 of an oil pulse unit, and when the cylinder rotates, a sealing convex portion 132 of the cylinder 120 abuts radially against a sealing protrusion 118 of a shaft portion 112, and at the same time, the raised portion 131 of the cylinder 120 abuts radially against the sliding member 140, thereby generating oil pressure in a divided space of a liquid-tight chamber 124. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5021240 Summary of the Invention [Problem to be solved by the invention]

[0004] To improve the efficiency of screw tightening work, it is desirable to have a large tightening torque.

[0005] An object of the present invention is to provide an oil pulse unit and a work machine that have a large tightening torque. [Means for solving the problem]

[0006] One aspect of the present invention is a substantially cylindrical liner extending in the front-rear direction and filled with oil, the liner having an inner circumferential portion, a first protrusion protruding radially inward from the inner circumferential portion, and a sliding portion provided radially inward of the inner circumferential portion; a shaft rotatably supported relative to the liner, the shaft including: a blade support portion located inside the liner; a second protrusion portion configured to face the first protrusion portion of the liner; and a tool holder portion that holds a tool bit; a blade supported by the blade support portion and configured to be slidable relative to the sliding portion of the liner; a spring that biases the blade toward the sliding portion of the liner; An oil pulse unit comprising: the oil pulse unit has a third protrusion portion that protrudes radially inward at the inner circumferential portion and the sliding portion of the liner and is configured to be able to abut against the blade in a rotational direction, When the liner rotates relative to the shaft, the third protrusion abuts against the blade in the rotational direction, transmitting a rotational impact force from the third protrusion to the blade, and at the same time, the first protrusion and the second protrusion face each other, applying oil pressure in the rotational direction to the blade. It is characterized by:

[0007] Another aspect of the present invention is a work machine, The oil pulse unit; a motor that drives the liner of the oil pulse unit; The present invention is characterized by the following.

[0008] The working machine of the present invention may be expressed as an "electric working machine," "power tool," "oil pulse tool," etc., and such expressions are also valid as aspects of the present invention. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide an oil pulse unit and a work machine with a large tightening torque. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a side cross-sectional view of a work machine 1 according to a first embodiment. [Figure 2] 4 is an exploded perspective view of a liner 41, a shaft 42, and blades 43, 44 of an oil pulse unit 40 of a work machine 1. FIG. [Figure 3] FIG. 4 is a cross-sectional view of the oil pulse unit 40. [Figure 4] 4 is an explanatory diagram of the operation of the oil pulse unit 40, showing the operation of the liner 41 relative to the shaft 42 for one rotation. FIG. [Figure 5] 4 is a diagram illustrating the operation of the oil pulse unit 40 when a torque pulse is generated. FIG. [Figure 6] FIG. 6 is a cross-sectional view of an oil pulse unit in a work machine according to a second embodiment. [Figure 7] FIG. 10 is an exploded perspective view of a liner 41, a shaft 42, and blades 143 and 144 of an oil pulse unit in a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] (Embodiment 1) 1 to 5 relate to a work machine 1 and an oil pulse unit 40 according to embodiment 1. The work machine 1 is an oil pulse tool (oil pulse driver). Figure 1 defines front-rear and up-down directions of the work machine 1 that are perpendicular to each other.

[0012] The work machine 1 has a housing 10. The housing 10 is, for example, a resin molded body having a structure divided into left and right halves. The housing 10 includes a motor housing portion 11, a handle portion 12, and a battery pack mounting portion 13.

[0013] The motor housing 11 is a cylindrical part whose central axis is approximately parallel to the front-to-rear direction. The upper end of the handle 12 is connected to the middle part of the motor housing 11 in the front-to-rear direction, and extends downward from the middle part. A trigger switch 14, which is an operation part that allows the user to switch the motor 30 between running and stopping, is provided at the upper end of the handle 12. The battery pack attachment part 13 is provided at the lower end of the handle 12, and a battery pack 18 can be attached detachably. The work machine 1 operates using power from the battery pack 18.

[0014] The work machine 1 has a hammer case 19. The hammer case 19 is made of, for example, metal, and is held in the motor housing portion 11 and extends forward from the motor housing portion 11. The work machine 1 has a protector 20. The protector 20 is a protective member made of elastomer or the like that covers the outer surface (surface) of the hammer case 19.

[0015] The work machine 1 has a motor 30, a reduction mechanism 38, and an oil pulse unit 40 inside the motor housing 11 and the hammer case 19. The motor 30 is an inner rotor type brushless motor and has a motor shaft 31 that is parallel to the front-to-rear direction. The reduction mechanism 38 is provided in front of the motor 30 and reduces the rotation of the motor 30 before transmitting it to the oil pulse unit 40 (oil pulse mechanism). The oil pulse unit 40 is housed in the hammer case 19 and is driven by the motor 30.

[0016] The oil pulse unit 40 has a liner 41 as a cylindrical member, a shaft 42 as an axial member, blades 43 and 44 as reciprocating members, a spring 45 as a biasing member, a liner upper plate 47, and a liner cap 48.

[0017] The liner 41 is driven by the rotational force of the motor 30. Specifically, the liner 41 is driven to rotate coaxially with the motor shaft 31 by the motor 30 via the reduction gear mechanism 38. The liner 41 is made of, for example, metal, and is configured in a tubular shape extending in the axial direction of the motor 30, specifically in a substantially cylindrical shape coaxial with the motor shaft 31, and is filled with oil (hydraulic oil). The axial direction of the motor 30 is parallel to the front-to-rear direction and is parallel to the axial direction of the liner 41 and the axial direction of the shaft 42, and will be referred to as the "axial direction" hereinafter. The radial direction of the liner 41 and the radial direction of the shaft 42 are the same direction, and will be referred to as the "radial direction" hereinafter.

[0018] As shown in FIG. 2, the liner 41 has an inner circumferential portion 66 and a sliding portion 61 (blade sliding portion). The inner circumferential portion 66 forms the inner circumferential surface of an oil chamber filled with oil. The sliding portion 61 is provided radially inward from the inner circumferential portion 66. The sliding portions 61 are surfaces on the front and rear sides of the inner circumferential portion 66 that face radially inward, and are configured to be able to abut against the radially outer portions of the front and rear portions of the blades 43, 44, respectively. The sliding portion 61 has a portion 61a that is approximately arc-shaped when viewed in the axial direction.

[0019] 3, the liner 41 has first protrusions 52, 53 that protrude radially inward from the inner circumferential portion 66. The first protrusions 52, 53 are configured to face second protrusions 56, 57 of the shaft 42. The liner 41 has third protrusions 54, 55 that protrude radially inward from the inner circumferential portion 66 and the sliding portion 61 and are configured to be able to abut against the blades 43, 44 in the rotational direction. The third protrusions 54, 55 protrude radially inward from a substantially arc-shaped portion 61a of the sliding portion 61.

[0020] The third protrusion 54 has a first inclined portion 54a and a second inclined portion 54b inclined with respect to the rotation direction of the liner 41, and a connecting portion 54c connecting the first inclined portion 54a and the second inclined portion 54b. The third protrusion 55 has a first inclined portion 55a and a second inclined portion 55b inclined with respect to the rotation direction of the liner 41, and a connecting portion 55c connecting the first inclined portion 55a and the second inclined portion 55b. The connecting portions 54c, 55c are configured as part of a substantially cylindrical surface centered on the rotation axis of the liner 41, and are configured to maintain the blades 43, 44 in a radially outer position (a second position described below) when the blades 43, 44 slide along the connecting portions 54c, 55c.

[0021] The shaft 42 is made of, for example, metal, and extends in the axial direction while being rotatably supported relative to the liner 41. A predetermined length of the shaft 42 from its rear end is housed inside the liner 41 and rotates inside the liner 41. The front end of the shaft 42 protrudes forward and outside the liner 41. The shaft 42 is coaxial with the motor shaft 31, and as shown in FIG. 1 , has a tool bit holding hole 51 at its front end as a tool bit holder. The tool bit holding hole 51 opens at the front end of the shaft 42 and holds a tool bit 15.

[0022] The shaft 42 has blade support holes 70 as blade support portions. The blade support holes 70 are located inside the liner 41. The blade support holes 70 are through-holes that penetrate the shaft 42 in the radial direction.

[0023] The shaft 42 has second protrusions 56, 57. The second protrusions 56, 57 each protrude radially outward from the outer surface of the shaft 42. The second protrusions 56, 57 are configured to face the first protrusions 52, 53 of the liner 41.

[0024] The blades 43, 44 are each supported in a blade support hole 70 of the shaft 42, and are rotatable integrally with the shaft 42 and are reciprocable relative to the shaft 42 between a first position and a second position. The first position is a radially outer position, and the second position is a radially inner position. The blades 43, 44 are housed inside the liner 41. The blades 43, 44 are each configured to be able to slide relative to the sliding portion 61 of the liner 41.

[0025] 2, each of the blades 43 and 44 has a substantially rectangular parallelepiped shape, with its radially outer surface being a curved surface that is convex radially outward. The radially inner portions of the blades 43 and 44 are positioned within the blade support holes 70. Two spring insertion holes 43a are formed in the radially inner surface of the blade 43. Two spring insertion holes 44a are formed in the radially inner surface of the blade 44.

[0026] Two springs 45 are inserted and held across the opposing insertion holes 43a, 44a. One end of each spring 45 is in the spring insertion hole 43a and the other end is in the spring insertion hole 44a. The springs 45 are, for example, compression coil springs, and are rotatable integrally with the shaft 42 and are expandable and contractible relative to the shaft 42. The springs 45 urge the blades 43, 44 from the second position toward the first position, i.e., urge the blades 43, 44 radially outward (toward the inner circumferential portion of the liner 41). The springs 45 urge the blades 43, 44 toward the sliding portion 61.

[0027] The liner upper plate 47 is supported integrally with the liner 41 at the rear of the liner 41 and rotates integrally with the liner 41. The liner upper plate 47 is connected to the rear end opening of the liner 41 and closes the rear end opening. The liner upper plate 47 rotatably supports the rear of the shaft 42. The liner cap 48 is threadedly attached to the rear end opening of the liner 41 and prevents the liner upper plate 47 from slipping off rearward. Note that the threads on the outer peripheral surface of the liner cap 48 and the threads on the inner peripheral surface of the liner 41 that screw into it are not shown in the figure.

[0028] The oil pulse unit 40 is configured to apply an intermittent rotational striking force and an intermittent rotational oil pressure to the blades 43, 44 by rotation of the liner 41 relative to the shaft 42.

[0029] The oil pulse unit 40 is configured so that when the liner 41 rotates relative to the shaft 42, the third protrusions 54, 55 abut against the blades 43, 44 in the rotational direction, transmitting a rotational impact force from the third protrusions 54, 55 to the blades 43, 44, and at approximately the same time, the first protrusions 52, 53 and the second protrusions 56, 57 face each other, applying rotational oil pressure to the blades 43, 44.

[0030] 4(a) to 4(h) are explanatory diagrams of the operation of the oil pulse unit 40, showing the movement of the liner 41 relative to the shaft 42 for one rotation at 45° intervals. The impact force in the rotational direction is generated in the states shown in FIGS. 4(a) and 4(e). The operation during the periods shown in FIGS. 4(a), (b), ..., (e) is similar to the operation during the periods shown in FIGS. 4(e), (f), ..., (a).

[0031] 4(a), the third protrusion 55 of the liner 41 strikes the blade 43, and the third protrusion 54 strikes the blade 44, transmitting a rotational striking force to the blades 43, 44. Immediately after this state, a seal (restricting the flow of oil) is formed by the close opposition of the first protrusion 52 of the liner 41 and the second protrusion 56 of the shaft 42, and a seal is also formed by the close opposition of the first protrusion 53 of the liner 41 and the second protrusion 57 of the shaft 42, and oil pressure is applied to the blades 43, 44 in the rotational direction.

[0032] 4(e), the third protrusion 54 of the liner 41 strikes the blade 43, and the third protrusion 55 strikes the blade 44, transmitting a rotational striking force to the blades 43, 44. Immediately after this state, a seal (restricting the flow of oil) is formed by the close opposition of the first protrusion 53 of the liner 41 and the second protrusion 56 of the shaft 42, and a seal is formed by the close opposition of the first protrusion 52 of the liner 41 and the second protrusion 57 of the shaft 42, and oil pressure is applied to the blades 43, 44 in the rotational direction.

[0033] 5(A) to 5(C) are explanatory diagrams of the operation of the oil pulse unit 40, showing, at small angle intervals, the operation when a torque pulse is generated from the liner 41 to the shaft 42. In Figures 5(B) and 5(C), the high-pressure chamber and the low-pressure chamber generated by the interaction of the contact between the blades 43 and 44 and the third protrusions 55 and 54 of the liner 41, and the engagement (close opposition) between the second protrusions 56 and 57 of the shaft 42 and the first protrusions 52 and 53 of the liner 41 are shown by hatching.

[0034] 5(A) shows the same state as in FIG. 4(a), that is, a state in which the third protrusion 55 of the liner 41 strikes the blade 43, and the third protrusion 54 strikes the blade 44. As shown in FIG. 5(A), the oil pulse unit 40 is configured such that, when the liner 41 rotates relative to the shaft 42 and the blades 43, 44 are in a first radial position (a radially outer position), the first inclined portion 54a of the third protrusion 54 abuts against the blade 44 in the rotational direction, transmitting an impact force in the rotational direction from the third protrusion 54 to the blade 44, and the first inclined portion 55a of the third protrusion 55 abuts against the blade 43, transmitting an impact force in the rotational direction from the third protrusion 55 to the blade 43. The tip of the blade 43 is formed with two chamfered portions configured to be in almost face-to-face contact with the first inclined portion 54a and the second inclined portion 55b, respectively, thereby increasing the contact area between the blade 43 and the first inclined portion 54a and the second inclined portion 55b, and reducing wear on both.

[0035] The enlarged portion B in FIG. 5A shows the impact force F applied to the blade 43 from the first inclined portion 55a, as well as the components F1 and F2 obtained by decomposing the impact force F into the circumferential and radial directions. The component F1 acts on the blade 43 as a rotational impact force, while the component F2 acts as a force that moves the blade 43 radially inward against the bias of the spring 45. Although not shown, a similar impact force is also applied to the blade 44 from the first inclined portion 54a, acting in a similar manner. To ensure smooth operation of the oil pulse unit 40, the blade 43 must be configured to move smoothly radially when the tip of the blade 43 abuts the first inclined portion 54a. To achieve this, it is desirable that the radial component F2 be greater than the rotational component F1. Specifically, the inclination angle of the first inclined portion 54a relative to the rotational direction is desirably set between 25 and 35 degrees. The most desirable inclination angle is 30 degrees. Similarly, the second tilt angle 55b with respect to the rotation direction is preferably set between 25 and 35 degrees, with the most preferable tilt angle being 30 degrees.

[0036] Figure 5(B) shows a state in which the liner 41 rotates from the state shown in Figure 5(A) and the blades 43, 44 are in the process of moving to a second radially inner position (radially inner position) due to the action of the first inclined portions 55a, 54a.

[0037] During the transition from FIG. 5(A) to FIG. 5(B), a seal (restricting oil flow) is formed by the close opposition between the first protrusion 52 of the liner 41 and the second protrusion 56 of the shaft 42, and a seal is formed by the close opposition between the first protrusion 53 of the liner 41 and the second protrusion 57 of the shaft 42. As the liner 41 rotates with the seal formed, the volume of the seal chamber on the opposite side of the rotation direction of the liner 41 from the blade 43 decreases and becomes a high-pressure chamber, while the volume of the seal chamber on the rotation direction side of the liner 41 increases and becomes a low-pressure chamber. As a result, oil pressure F5 is applied to the blade 43 in the rotation direction, and similarly, oil pressure is applied to the blade 44. At the same time, a load F4 is applied to the blade 43 from the first inclined portion 55a of the liner 41. The load F4 is the circumferential component of the load applied to the blade 43 from the first inclined portion 55a (a load in the same direction as the impact force F). A similar load is applied to the blade 44 from the first inclined portion 54a and acts in the same manner.

[0038] 5(C) shows the initial state in which the liner 41 has rotated from the state shown in FIG. 5(B) and the blades 43, 44 have begun to slide against the connecting portions 55c, 54c. In this state, the sealing (oil flow restriction) due to the close opposition between the first protrusion 52 of the liner 41 and the second protrusion 56 of the shaft 42, and the sealing due to the close opposition between the first protrusion 53 of the liner 41 and the second protrusion 57 of the shaft 42 continue, and oil pressure F5 in the rotational direction is applied to the blades 43, 44. Meanwhile, the load from the first inclined portions 55a, 54a of the liner 41 to the blades 43, 44 is eliminated.

[0039] As shown in the state transitions in Figures 5(A) to (C), the oil pulse unit 40 is configured so that when the liner 41 rotates relative to the shaft 42, a rotational impact force is transmitted from the third protrusions 55, 54 to the blades 43, 44, and then the blades 43, 44 move to a second position radially inward due to the action of the first inclined portions 55a, 54a and slide along the connecting portions 55c, 54c.

[0040] The oil pulse unit 40 is configured so that when the liner 41 rotates relative to the shaft 42, the third protrusions 55, 54 come into contact with the blades 43, 44 in the rotational direction, and a rotational impact force begins to be transmitted from the third protrusions 55, 54 to the blades 43, 44, and then the first protrusions 52, 53 and the second protrusions 56, 57 face each other, and rotational oil pressure is applied to the blades 43, 44.

[0041] The oil pulse unit 40 is configured such that the liner 41 rotates relative to the shaft 42 from the state shown in Figure 5(C), the blades 43, 44 slide along the connection portions 55c, 54c, and then the blades 43, 44 slide along the second inclined portions 55b, 54b to move to the first position (radially outer position).

[0042] This embodiment has the following advantages.

[0043] (1) The oil pulse unit 40 is configured so that, when the liner 41 rotates relative to the shaft 42, the third protrusions 54, 55 come into contact with the blades 43, 44 in the rotational direction, transmitting an impact force in the rotational direction from the third protrusions 54, 55 to the blades 43, 44, and at approximately the same time, the first protrusions 52, 53 and the second protrusions 56, 57 face each other, applying oil pressure in the rotational direction to the blades 43, 44. Because the third protrusions 54, 55 are configured to protrude radially inward at the sliding portion 61 and be able to come into contact with the blades 43, 44, a large impact force is transmitted from the third protrusions 54, 55 to the blades 43, 44, resulting in a large tightening torque.

[0044] (2) Since the first inclined portions 54a, 55a of the third protrusions 54, 55 strike the blades 43, 44, the striking force in the rotational direction can be adjusted by the inclination angle of the first inclined portions 54a, 55a, which is advantageous in terms of design.

[0045] (3) The blades 43, 44 are configured to slide along the second inclined portions 55b, 54b to move from the second position (the radially inner position) to the first position (the radially outer position). This prevents the blades 43, 44 from suddenly changing their positions in the radial direction, thereby preventing instability in their operation.

[0046] (4) The oil pulse unit 40 is configured so that oil pressure is applied to the blades 43, 44 after the rotational impact force begins to be transmitted to the blades 43, 44. Therefore, compared to a configuration in which oil pressure is applied before the impact force is transmitted to the blades 43, 44, the rotational speed of the liner 41 immediately before impact is increased, and the impact force is increased.

[0047] (5) Because the third protrusions 54, 55 have connecting portions 54c, 55c, the time during which oil pressure is applied to the blades 43, 44 can be extended, compared to a configuration in which the first inclined portions 54a, 55a and the second inclined portions 54b, 55b are directly connected without the intermediary of the connecting portions 54c, 55c, thereby improving the screw tightening speed.

[0048] (Embodiment 2) Fig. 6 is a cross-sectional view of the oil pulse unit in the work machine according to embodiment 2. Fig. 7 is an exploded perspective view of the liner 41, shaft 42, and blades 143, 144 of the oil pulse unit in embodiment 2. The following description will focus on the differences from embodiment 1.

[0049] In the oil pulse unit of the second embodiment, the blades 43 and 44 of the oil pulse unit 40 of the first embodiment are replaced with blades 143 and 144. The blades 143 and 144 have recesses 145 and 146, respectively. The recesses 145 and 146 are configured as recessed grooves extending in the axial direction.

[0050] 6, the recesses 145, 146 are configured to connect the inside of the blade support hole 70 of the shaft 42 with the low-pressure chamber around the time when the sliding object of the blades 143, 144 switches from the first inclined portions 55a, 54a of the third protrusions 55, 54 to the connecting portions 55c, 54c (when the blades 143, 144 are detached from the liner 41), and to facilitate the escape of oil compressed between the blades 143, 144 from the inside of the blade support hole 70 to the low-pressure chamber. This makes it easier for the blades 143, 144 to retreat toward the inside of the blade support hole 70, reducing wear on the third protrusions 54, 55.

[0051] Although the present invention has been described above using the embodiments as examples, the present invention is not limited to these embodiments. Various modifications are possible to the details specifically described in the embodiments within the scope of the claims. For example, the motor 30 may be a brushed motor. Furthermore, the power source for the work machine may be an external AC power source such as a commercial power source. [Explanation of symbols]

[0052] 1...Work machine, 10...Housing, 11...Motor accommodating section, 12...Handle section, 13...Battery pack mounting section, 14...Trigger switch, 15...Tip tool, 18...Battery pack, 19...Hammer case, 20...Protector (protective member), 30...Motor, 31...Motor shaft, 38...Reduction mechanism, 40...Oil pulse unit, 41...Liner (cylindrical member), 42...Shaft (axial member), 43, 44...Blade (reciprocating member), 43a, 44a...Spring insertion hole, 45...Spring (biasing member), 4 7...liner upper plate, 48...liner cap, 51...tool holding hole (tool holding portion), 52, 53...first protrusion, 54, 55...third protrusion, 54a, 55a...first inclined portion, 54b, 55b...second inclined portion, 54c, 55c...connection portion, 56, 57...second protrusion, 61...sliding portion (blade sliding portion), 61a...substantially arc-shaped portion, 66...inner peripheral portion, 70...blade support hole (blade support portion), 143, 144...blade (reciprocating member), 145, 146...recess.

Claims

1. a substantially cylindrical liner extending in the front-rear direction and filled with oil, the liner having an inner circumferential portion, a first protrusion protruding radially inward from the inner circumferential portion, and a sliding portion provided radially inward of the inner circumferential portion; a shaft rotatably supported relative to the liner, the shaft including: a blade support portion located inside the liner; a second protrusion portion configured to face the first protrusion portion of the liner; and a tool holder portion that holds a tool; a blade supported by the blade support portion and configured to be slidable relative to the sliding portion of the liner; a spring that biases the blade toward the sliding portion of the liner; An oil pulse unit comprising: the oil pulse unit has a third protrusion portion that protrudes radially inward from the inner circumferential portion and the sliding portion of the liner and is configured to be able to abut against the blade in a rotational direction, When the liner rotates relative to the shaft, the third protrusion abuts against the blade in the rotational direction, transmitting a rotational impact force from the third protrusion to the blade, and at the same time, the first protrusion and the second protrusion face each other, applying oil pressure in the rotational direction to the blade. An oil pulse unit characterized by:

2. 2. The oil pulse unit according to claim 1, The sliding portion has a substantially arc-shaped portion when viewed from the axial direction, the third protrusion protrudes radially inward from the substantially arc-shaped portion of the sliding portion; An oil pulse unit characterized by:

3. 2. The oil pulse unit according to claim 1, The third protrusion is a first inclined portion and a second inclined portion inclined with respect to a rotation direction of the liner; a connection portion connecting the first inclined portion and the second inclined portion, An oil pulse unit characterized by:

4. 3. The oil pulse unit according to claim 2, When the liner rotates relative to the shaft, the first inclined portion of the third protrusion abuts against the blade in the rotational direction with the blade at a first radial position, so that a striking force in the rotational direction is transmitted from the third protrusion to the blade. An oil pulse unit characterized by:

5. 3. The oil pulse unit according to claim 2, When the liner rotates relative to the shaft, a rotational impact force is transmitted from the third protrusion to the blade, and then the blade moves to a second position radially inward by the action of the first inclined portion and slides along the connection portion. An oil pulse unit characterized by:

6. 5. The oil pulse unit according to claim 4, the connecting portion is configured as a part of a substantially cylindrical surface centered on the rotation axis of the liner, and is configured to maintain the blade in the second radial position when the blade slides along the connecting portion. An oil pulse unit characterized by:

7. 5. The oil pulse unit according to claim 4, When the liner rotates relative to the shaft, the blade slides along the connecting portion, and then the blade slides along the second inclined portion and moves to the first position radially outward. An oil pulse unit characterized by:

8. 2. The oil pulse unit according to claim 1, When the liner rotates relative to the shaft, the third protrusion comes into contact with the blade in the rotational direction, and a rotational impact force is transmitted from the third protrusion to the blade. Then, the first protrusion and the second protrusion face each other, and oil pressure in the rotational direction is applied to the blade. An oil pulse unit characterized by:

9. The oil pulse unit according to claim 1; a motor that drives the liner of the oil pulse unit; A work machine characterized by comprising:

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