Electric tool

Abstract

The invention provides an electric tool. The electric tool has a motor. The electric tool has a rotation direction restricting mechanism (40) that restricts the rotation direction of the electric tool by the output of the motor. The rotation direction restricting mechanism has an outer ring (41). The rotation direction restricting mechanism has an inner peripheral member (42) provided on the inner peripheral side of the outer ring. The rotation direction restricting mechanism has a plurality of cam surfaces (43) recessed in an outer peripheral surface (42a) of the inner peripheral member. The rotation direction restricting mechanism has a lock member (44) which is movably disposed within the cam surface, permits rotation of the outer ring and the inner peripheral member in a first direction (R1) that opposes each other, and restricts rotation of the outer ring and the inner peripheral member in a second direction (R2) that opposes each other. The rotation direction restricting mechanism has a protrusion (eccentric mechanism) (45) that causes the outer ring and the inner peripheral member to be eccentric from each other. Therefore, the electric tool provided with the rotation direction limiting mechanism capable of more reliably limiting the rotation direction based on the output of the motor to one direction is provided.

Description

Technical Field

[0001] The present invention relates to a power tool driven by the output of a motor. Background Art

[0002] For example, as one of the power tools, a so-called gas spring type driving tool is disclosed in Patent Document 1. The driving tool has a driver for striking a driving member, a lifting mechanism for moving the driver to a standby position or a top dead center, and a motor as a driving source of the lifting mechanism. The driving tool has a cylinder extending in the driving direction, and a piston that can move in the cylinder and is connected to the driver. When the driver and the piston are moved in a direction opposite to the driving direction by the lifting mechanism, the air pressure in the pressure accumulation chamber sealed above the cylinder increases. The driver uses this air pressure as a driving force to move in the driving direction and strike the driving member.

[0003] The lifting mechanism, for example, moves the driver and the piston in a direction opposite to the driving direction by rotating in the first direction. Therefore, the lifting mechanism is subjected to a force that wants to rotate in the second direction opposite to the first direction due to the air pressure in the pressure accumulation chamber. In the case where the lifting mechanism can freely rotate in the second direction, the driver and the piston cannot be held against the air pressure. Therefore, a one-way clutch mechanism, for example, is provided in any area from the motor to the lifting mechanism as a mechanism for restricting the rotation direction to one direction.

[0004] The one-way clutch mechanism has, for example, a substantially disk-shaped inner peripheral member that transmits rotational power, and a substantially cylindrical outer ring that surrounds the outer periphery of the inner peripheral member. A cam surface is recessed in either the outer peripheral surface of the inner peripheral member or the inner peripheral surface of the outer ring. A locking member such as a cylindrical pin is inserted into the cam surface. One circumferential end side of the cam surface is provided with a relatively wide width in the radial direction, and the other circumferential end side is provided with a relatively narrow width in the radial direction. When the inner peripheral member rotates in the first direction, the locking member moves to the side where the width of the cam surface is wider. Therefore, the inner peripheral member can rotate in the first direction without being restricted. When the inner peripheral member wants to rotate in the second direction opposite to the first direction, the locking member moves to the side where the width of the cam surface is narrower. Therefore, the locking member is sandwiched between the inner peripheral member and the outer ring. Accordingly, the rotation of the inner peripheral member in the second direction is restricted.

[0005] In the prior art, the structures of the one-way clutch mechanism are symmetrically arranged with respect to the rotation center point of the inner peripheral member. In such a configuration, sometimes the rotation in the second direction cannot be sufficiently restricted. For example, a gear set coated with grease is provided around the one-way clutch mechanism. For example, due to heat during driving or the like, the grease enters the cam surface of the one-way clutch mechanism, and then cools and solidifies or the viscosity increases. At this time, there is a case where the grease hinders the movement of the locking member, so that the locking member cannot move to the side where the width of the cam surface is narrow. Thus, if the movement of the locking member is restricted, the rotation of the inner peripheral member in the second direction cannot be restricted.

[0006] In the one-way clutch mechanism of the prior art, for example, there is also a mechanism in which a spring or the like that always biases the locking member toward the side where the width of the cam surface is narrow is provided. However, space is required to provide a structure that always biases the locking member. For example, when a one-way clutch mechanism is provided in a mechanism with a large number of components such as a planetary gear mechanism, it is difficult to ensure space without interfering with each component. For example, if the number of gears is to be increased, there is insufficient space to arrange a spring or the like. In addition, the cost increases due to the assembly of a spring or the like. [Prior Art Documents] [Patent Documents]

[0007] Patent Document 1: Japanese Patent Publication No. 6627990 Summary of the Invention [Technical Problem to be Solved by the Invention]

[0008] Therefore, there is a need for a power tool having a rotation direction restricting mechanism that can more reliably restrict the rotation direction of the rotation based on the output of the motor to one direction. [Technical Solution for Solving the Technical Problem]

[0009] According to one feature of the present disclosure, a power tool has a motor. The power tool has a rotation direction restricting mechanism that restricts the rotation direction of the rotation by the output of the motor. The rotation direction restricting mechanism has an outer ring. The rotation direction restricting mechanism has an inner peripheral member provided on the inner peripheral side of the outer ring. The rotation direction restricting mechanism has a plurality of cam surfaces recessed in the inner peripheral surface of the outer ring or the outer peripheral surface of the inner peripheral member. The rotation direction restricting mechanism has a locking member that is movably arranged in the cam surface, allowing the relative rotation in the first direction of the outer ring and the inner peripheral member and restricting the relative rotation in the second direction. The rotation direction restricting mechanism has an eccentric mechanism that makes the outer ring and the inner peripheral member eccentric to each other.

[0010] Therefore, the outer ring and the inner peripheral member are eccentric to each other by the eccentric mechanism. As a result, a part of the plurality of cam surfaces is disposed at a position where the outer ring and the inner peripheral member are in close contact with each other in the radial direction. Therefore, at least a part of the locking members inserted into the cam surfaces can be in close contact with both the outer ring and the inner peripheral member. Therefore, when the outer ring and the inner peripheral member are about to rotate relative to each other in the second direction, the locking members are reliably clamped between the outer ring and the inner peripheral member. Accordingly, the relative rotational direction of the outer ring and the inner peripheral member can be more reliably restricted to one direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a right view of the power tool according to the first embodiment. Figure 2 is Figure 1 a II-II cross-sectional view in [reference numeral], showing the driving tool when the driver is in the standby position. Figure 3 is Figure 1 a III-III cross-sectional view in [reference numeral]. Figure 4 is an exploded perspective view of the planetary gear mechanism. Figure 5 is an exploded perspective view of the rotation direction restricting mechanism. Figure 6 is Figure 3 a VI-VI cross-sectional view in [reference numeral], showing the state where the rotation direction restricting mechanism rotates forward. Figure 7 is Figure 3 a VI-VI cross-sectional view in [reference numeral], showing the state when the rotation direction restricting mechanism starts to restrict reverse rotation. Figure 8 is Figure 3 a VI-VI cross-sectional view in [reference numeral], showing the state after the rotation direction restricting mechanism restricts reverse rotation. Figure 9 is Figure 6 a cross-sectional view of the planetary gear mechanism in the IX-IX section in [reference numeral]. Figure 10 is Figure 6 a cross-sectional view of the gear box in the X-X section in [reference numeral]. Figure 11 is a front view of the rotation direction restricting mechanism according to the second embodiment. Figure 12 is a front view of the rotation direction restricting mechanism according to the third embodiment. Figure 13 is a front view of the rotation direction restricting mechanism according to the fourth embodiment. [DESCRIPTION OF REFERENCE NUMERALS] 1: Power tool; 2: Driving head of the driving machine; 2a: Driving passage; 2b: Ejection port; 3: Contact arm; 3a: Regulator connection part; 4: Driving tool guide; 5: Handle; 6: Trigger; 6a: Trigger switch; 7: Battery mounting part; 8: Battery; 9: Controller; 10: Tool body; 11: Body housing; 11a: Mechanism housing, 11b: Window part; 12: Cylinder; 13: Pressure accumulation chamber; 13a: Air chamber; 14: Piston; 15: Driving tool; 15a: Rack teeth (engaged part); 15b: Tip; 16: Buffer; 20: Motor; 20a: Motor shaft; 20b, 20c: Bearings; 20d: Driving gear; 21: Fan; 22: Lifting mechanism; 23: Rotating shaft; 23a: Spline shaft; 24: Wheel part; 25: Engaging part; 25a: Final engaging part; 26: Nail magazine; 27: Pusher; 28: Regulator; 28a: Rotating shaft; 28b: Compression spring; 29: Switch; 29a: Protruding pin; 29b: Spring; 30: Planetary gear mechanism; 31: First planetary gear set; 31a: (Upstream side) planetary gear; 31b: (Upstream side) internal gear; 31c: Planet carrier (inner peripheral part); 31d: Support shaft; 31e: Gear outer peripheral part; 31f: Convex part; 31g: Planet carrier outer peripheral part (outer ring); 31h: Convex part; 31i: Washer; 31j: Washer; 31k: Hole; 32: Second planetary gear set; 32a: Sun gear; 32b: (Downstream side) planetary gear; 32c: (Downstream side) internal gear; 32d: Planet carrier; 32e: Support shaft; 32f: Gear outer peripheral part; 32g: Convex part; 32h: Planet carrier outer peripheral part; 32i: Washer; 33: Third planetary gear set; 33a: Sun gear; 33b: Planetary gear; 33c: Internal gear; 33d: Planet carrier; 33e: Support shaft; 33f: Spline groove; 33g: Gear outer peripheral part; 33h: Convex part; 33i: Washer; 34: Gear box (holding part); 34a: Inner peripheral surface; 34b: Engaging recess; 34c: Bottom surface; 35: Bearing; 40: Rotation direction limiting mechanism; 41: Outer ring; 41a: Outer peripheral surface; 41b: Inner peripheral surface; 41c: Inner peripheral surface center; 42: Inner peripheral part; 42a: Outer peripheral surface; 42b: Rotation center; 43: Cam surface; 43a: Widening part; 43b: Narrowing part; 44: Locking part; 45: Protrusion (eccentric mechanism); 50: Power tool; 51: Rotation direction limiting mechanism; 52: Outer ring; 52a: Outer peripheral surface; 52b: Inner peripheral surface; 52c: Outer peripheral surface center; 52d: Inner peripheral surface center; 53: Inner peripheral part; 53a: Outer peripheral surface; 53b: Rotation center; 54: Cam surface; 54a: Widening part; 54b: Narrowing part; 55: Locking part; 60: Power tool; 61: Rotation direction limiting mechanism; 62: Outer ring; 62a: Outer peripheral surface; 62b: Inner peripheral surface; 63: Inner peripheral part; 63a: Outer peripheral surface; 63b: Rotation center; 63c: Eccentric center; 64: Cam surface64a: Widening portion; 64b: Narrowing portion; 65: Locking member; 70: Power tool; 71: Rotation direction restricting mechanism; 72: Outer ring; 72a: Outer peripheral surface; 72b: Inner peripheral surface; 72c: Center of the inner peripheral surface; 73: Inner peripheral member; 73a: Outer peripheral surface; 73b: Rotation center; 74: Cam surface; 74a: Widening portion; 74b: Narrowing portion; 75: Locking member; 76: Projection (eccentric mechanism); N: Driving member; W: Driven member; J: Motor axis; R1: First direction; R2: Second direction; D1: Outer diameter (of the internal gear); D2: Outer diameter (of the outer ring).; Detailed implementation mode

[0012] According to other features of the present disclosure, the power tool has a holding member surrounding the outer ring. A projection serving as an eccentric mechanism that protrudes toward the other party and abuts against the other party is provided on one of the outer ring and the holding member. Therefore, the outer ring and the inner peripheral member can be made eccentric to each other by a simple structure in which a projection is provided on the outer ring or the holding member. Therefore, the rotation direction restricting mechanism can be provided without significant changes compared with the existing structure, and the rotation direction can be more reliably restricted to one direction.

[0013] According to other features of the present disclosure, the inner peripheral member can be rotated by a motor. The outer ring has an inner peripheral surface eccentric with respect to the rotation center of the inner peripheral member. Therefore, for example, when the inner peripheral member rotates, the inner peripheral surface of the outer ring and the outer peripheral surface of the inner peripheral member can be made eccentric to each other while making the inner peripheral member axially symmetric. Therefore, the wobbling of the inner peripheral member can be suppressed, and the rotation direction can be more reliably restricted to one direction.

[0014] According to other features of the present disclosure, the inner peripheral member can be rotated by a motor. The inner peripheral member has an outer peripheral surface eccentric with respect to the rotation center of the inner peripheral member. Therefore, the outer ring can be assembled in the same manner as the existing structure, and the inner peripheral surface of the outer ring and the outer peripheral surface of the inner peripheral member can be made eccentric to each other, so that the rotation direction can be more reliably restricted to one direction.

[0015] According to other features of the present disclosure, the cam surface is provided on the inner peripheral member. Therefore, when the inner peripheral member rotates, the locking member can be smoothly moved along the cam surface by centrifugal force. Accordingly, the rotation in the first direction can be more reliably allowed and the rotation in the second direction can be restricted.

[0016] According to other features of the present disclosure, the power tool has a holding member that surrounds the outer ring and restricts the rotation of the outer ring. The inner peripheral member can be rotated by a motor. Therefore, the outer ring is provided so as not to rotate integrally with the holding member, and the inner peripheral member is provided as a component that rotates by the output of the motor. Accordingly, for example, the rotation direction restricting mechanism can be provided in a gear set or the like that converts and transmits the output of the motor.

[0017] According to other features of the present disclosure, the power tool has a planetary gear mechanism that decelerates the rotation of the motor-based output. The planetary gear mechanism has planetary gears rotatably held by an inner peripheral member. Therefore, a rotation direction restricting mechanism that can more reliably restrict the rotation direction to one direction can be provided in the planetary gear mechanism with a large number of components and a small space.

[0018] According to other features of the present disclosure, the planetary gear mechanism has an internal gear that engages with the planetary gears. The internal gear and the outer ring are arranged and housed in the gearbox. The outer diameter of the outer ring is smaller than the outer diameter of the internal gear. Therefore, by making the outer diameter of the outer ring smaller than the outer diameter of the internal gear, a gap can be provided between the outer diameter of the outer ring and the inner peripheral surface of the gearbox. The center of the internal gear is located at the center of the gearbox. Therefore, the outer ring can be eccentric with respect to the center of the internal gear through the gap.

[0019] According to other features of the present disclosure, the power tool has a planetary gear mechanism that decelerates the rotation of the motor-based output. The planetary gear mechanism has an upstream internal gear. The planetary gear mechanism has an upstream planetary gear that engages with the upstream internal gear. The planetary gear mechanism has a downstream internal gear. The planetary gear mechanism has a downstream planetary gear that engages with the downstream internal gear. The upstream internal gear, the outer ring, and the downstream internal gear are sequentially housed in the gearbox. A protrusion serving as an eccentric mechanism that protrudes toward the outer ring and abuts against the outer ring is provided in the gearbox. The protrusion makes a part of the inner diameter of the gearbox smaller than the outer diameters of the upstream internal gear and the downstream internal gear.

[0020] Therefore, the outer ring can be assembled together with the components of the planetary gear mechanism into the gearbox. Moreover, the protrusion of the gearbox is provided so as not to interfere with components other than the outer ring, such as the upstream internal gear and the downstream internal gear. In this way, while not interfering with the drive of the planetary gear mechanism, only the outer ring can be eccentric with respect to the rotation center of the inner peripheral member.

[0021] According to other features of the present disclosure, the power tool has a lifting mechanism that stores energy through the output of the motor. The power tool has a driver that moves in the driving direction by the energy stored by the lifting mechanism to drive a driving member. Therefore, the lifting mechanism stores energy by rotating forward. If the lifting mechanism rotates in reverse due to the stored energy, the stored energy is lost and a normal driving operation cannot be performed. By allowing the rotation direction of the lifting mechanism to be only the forward rotation direction by the rotation direction restricting mechanism, the inadvertently loss of the stored energy can be suppressed.

[0022] According to other features of the present disclosure, the electric tool has a planetary gear mechanism that reduces the speed of rotation based on the output of the motor. The planetary gear mechanism has an upstream internal gear. The planetary gear mechanism has an upstream planetary gear that engages with the upstream internal gear. The planetary gear mechanism has a downstream internal gear. The planetary gear mechanism has a downstream planetary gear that engages with the downstream internal gear. A downstream internal gear is provided on the downstream side of the rotation direction limiting mechanism. Therefore, the output of the motor is reduced in the downstream internal gear on the downstream side of the rotation direction limiting mechanism. Therefore, at a stage where the output torque is still small, the rotation direction can be limited to one direction by the rotation direction limiting mechanism. Accordingly, the rotation direction can be more reliably limited by the rotation direction limiting mechanism.

[0023] Next, based on Figures 1 to 10 The first embodiment of the present disclosure is described. As an example of the electric tool 1, a gas spring type driving tool that uses the gas pressure of the pressure storage chamber as the thrust for driving the driven part is illustrated. In the following description, the driving direction of the driven part is set as the downward direction, and the direction opposite to the driving direction is set as the upward direction. The user of the electric tool 1 is located at Figure 1 The center is the left side of the electric tool 1. The user's near side is set as the rear direction, and the far side opposite to the near side is set as the front direction. The left and right directions are based on the user.

[0024] like Figure 2 As shown, the electric tool 1 has a tool body 10 and a main body housing 11 covering the tool body 10. A cylinder 12 extending in the up-down direction is housed in the main body housing 11. A piston 14 is housed in the cylinder 12 in a manner that allows it to reciprocate up and down. A driver 15 that is longer up and down is connected to the lower surface of the piston 14. The upper end of the cylinder 12 is connected to a pressure storage chamber 13. A compressed gas such as air is sealed in the pressure storage chamber 13. The air pressure of the pressure storage chamber 13 acts as a thrust that applies force to the upper surface of the piston 14 to move it downward. The right part of the pressure storage chamber 13 is connected to an air chamber 13a extending downward. The air chamber 13a extends downward along the right side surface of the cylinder 12. The air chamber 13a is arranged above the lifting mechanism 22 in a manner that overlaps with the lifting mechanism 22 described later in the left-right direction.

[0025] like Figure 1 , 2As shown, a driving machine head 2 is provided at the lower part of the tool body 10. The driving machine head 2 has a driver guide 4 extending substantially in the vertical direction. Inside the driver guide 4, a driving passage 2a extending in the vertical direction is provided. The lower end of the driving passage 2a opens downward as a shooting outlet 2b. The driving machine head 2 has a contact arm 3 that abuts against the workpiece W to be driven. The contact arm 3 can move in the vertical direction relative to the driver guide 4. The contact arm 3 is urged downward by a compression spring 28b provided at the front part of the tool body 10. In a state where the lower end of the contact arm 3 abuts against the workpiece W to be driven, the tool body 10 is further moved closer to the workpiece W to be driven. Accordingly, the contact arm 3 is pressed by the workpiece W to be driven and moves upward.

[0026] As Figure 2 shown, the lower part of the driver 15 enters the driving passage 2a. The driver 15 moves downward by the air pressure in the accumulator chamber 13 acting on the upper surface of the piston 14. The tip 15b of the driver 15 strikes the head of a driving member N supplied to the driving passage 2a when it moves to the driving position. The struck driving member N is ejected from the shooting outlet 2b and driven into the workpiece W to be driven. A substantially cylindrical cushion 16 for absorbing the impact at the bottom dead center of the piston 14 is provided inside the lower side of the cylinder 12.

[0027] As Figure 2 shown, a plurality of rack teeth (engaged portions) 15a protruding rightward are provided on the right side portion of the driver 15. In this embodiment, seven rack teeth 15a are arranged in the vertical direction, which is the longitudinal direction of the driver 15. Each rack tooth 15a is provided in a substantially triangular shape with the bottom facing downward, which is the driving direction, when viewed from the front. The bottom of the rack tooth 15a engages with the engaging portion 25 of the lifting mechanism 22.

[0028] As Figure 1 shown, a grip 5 extending rearward and for the user to hold is provided at the rear part of the tool body 10. A trigger 6 for the user to operate by pressing with a fingertip is provided on the lower front surface of the grip 5. A trigger switch 6a is provided inside the grip 5, and the trigger switch 6a switches from the off state to the on state in response to the pressing operation of the trigger 6. The pressing operation of the trigger 6 is effective when the driving machine head 2 is pressed by the workpiece W to be driven and moves upward to the upper position.

[0029] As Figure 1As shown, a battery mounting portion 7 extending in the vertical direction is provided on the rear surface of the grip 5. The battery 8 can be detachably mounted on the battery mounting portion 7. The battery 8 can be removed from the battery mounting portion 7 and repeatedly charged by a separately prepared charger for use. The battery 8 can be used as a common power source for other power tools. The battery 8 supplies power to the motor 20 and the like described later. A controller 9 that mainly controls the driving of the motor 20 is housed in the battery mounting portion 7. The controller 9 is arranged such that a control board is housed in a shallow-bottomed rectangular box-shaped housing. The controller 9 is disposed in front of the battery 8 mounted on the battery mounting portion 7. The controller 9 is arranged in a posture where the longest side extends substantially in the vertical direction and the shortest side extends substantially in the front-rear direction.

[0030] As Figure 1 shown, the main body housing 11 has a substantially cylindrical mechanism housing 11a extending in the front-rear direction below the grip 5. The rear portion of the mechanism housing 11a is connected to the lower portion of the battery mounting portion 7. The grip 5, the battery mounting portion 7, and the mechanism housing 11a cooperate to form a ring shape. The motor 20, the planetary gear mechanism 30, and the lifting mechanism 22 are sequentially housed in the mechanism housing 11a in the order from the rear to the front. The motor 20, the planetary gear mechanism 30, and the lifting mechanism 22 are arranged in the extending direction of the motor axis J extending in the front-rear direction.

[0031] As Figure 3 shown, the motor 20 has a motor shaft 20a extending in the front-rear direction on the motor axis J. The rear portion of the motor shaft 20a is rotatably supported by a bearing 20b. The front portion of the motor shaft 20a is rotatably supported by a bearing 20c provided at the rear portion of the planetary gear mechanism 30. A fan 21 is mounted in front of the front portion of the motor shaft 20a and behind the bearing 20c. The fan 21 rotates integrally with the motor shaft 20a, whereby cooling air flows from the rear to the front in the mechanism housing 11a. A drive gear 20d that meshes with the planetary gear mechanism 30 is provided at the front end of the motor shaft 20a.

[0032] As Figure 3 and 4As shown, the planetary gear mechanism 30 has three stages of planetary gear sets 31, 32, and 33. The three stages of planetary gear sets 31, 32, and 33 are coaxial with each other and are coaxially arranged with the motor axis J. The rotational output of the motor 20 is decelerated by the planetary gear mechanism 30 including the three stages of planetary gear sets 31, 32, and 33 and transmitted to the lifting mechanism 22. The planetary gear mechanism 30 has a gearbox 34 that houses the three stages of planetary gear sets 31, 32, and 33. The gearbox 34 is made of resin, for example. The gearbox 34 is held in the mechanism housing 11a so as not to move within the mechanism housing 11a. A plurality of engaging recesses 34b are provided on the substantially cylindrical inner peripheral surface 34a of the gearbox 34. The engaging recesses 34b are recessed radially outward and extend in the front-rear direction from the bottom surface 34c of the gearbox 34 to the front end of the gearbox 34.

[0033] As Figure 3 , 4 shown, the first planetary gear set 31 has three planetary gears 31a, one internal gear 31b, and one planet carrier 31c. The three planetary gears 31a mesh with the drive gear 20d of the motor shaft 20a. The drive gear 20d corresponds to the sun gear of the first planetary gear set 31. A substantially cylindrical gear outer peripheral member 31e is provided on the outer peripheral side of the internal gear 31b, and the gear outer peripheral member 31e has a plurality of convex portions 31f that protrude radially outward. The gear outer peripheral member 31e is housed along the inner peripheral surface 34a of the gearbox 34. By inserting the plurality of convex portions 31f into the engaging recesses 34b of the gearbox 34, the internal gear 31b is stopped from rotating relative to the gearbox 34.

[0034] As Figure 3 , 4 shown, the three planetary gears 31a also mesh with the internal gear 31b. The three planetary gears 31a are respectively rotatably supported by the planet carrier 31c via support shafts 31d. Washers 31i are sandwiched behind the three planetary gears 31a and the internal gear 31b.

[0035] As Figure 3 , 4As shown, a substantially cylindrical planetary carrier outer peripheral member 31g is provided on the outer peripheral side of the planetary carrier 31c. The planetary carrier outer peripheral member 31g has a plurality of convex portions 31h that project radially outward. The planetary carrier outer peripheral member 31g is housed along the inner peripheral surface 34a of the gear box 34. By inserting the plurality of convex portions 31h into the engagement recesses 34b of the gear box 34, the planetary carrier outer peripheral member 31g is stopped from rotating relative to the gear box 34. The planetary gear mechanism 30 has a rotation direction restricting mechanism 40 that includes the planetary carrier 31c and the planetary carrier outer peripheral member 31g. By the rotation direction restricting mechanism 40, rotation in the first direction (counterclockwise when viewed from the front) of the rotational output is allowed, and rotation in the second direction opposite to the first direction is restricted. The rotation direction restricting mechanism 40 will be described in detail later.

[0036] As Figure 3 , 4 shown, the sun gear 32a of the second planetary gear set 32 is integrally formed on the front surface of the planetary carrier 31c of the first planetary gear set 31. The second planetary gear set 32 has four planetary gears 32b, one internal gear 32c, and one planetary carrier 32d. The four planetary gears 32b are engaged with the sun gear 32a. A substantially cylindrical gear outer peripheral member 32f is provided on the outer peripheral side of the internal gear 32c. The gear outer peripheral member 32f has a plurality of convex portions 32g that project radially outward. The gear outer peripheral member 32f is housed along the inner peripheral surface 34a of the gear box 34. By inserting the plurality of convex portions 32g into the engagement recesses 34b of the gear box 34, the internal gear 32c is stopped from rotating relative to the gear box 34.

[0037] As Figure 3 , 4 shown, the four planetary gears 32b are also engaged with the internal gear 32c. The four planetary gears 32b are respectively rotatably supported by the support shafts 32e on the planetary carrier 32d. A washer 32i is sandwiched between the four planetary gears 32b and the internal gear 32c at the rear. A cylindrical planetary carrier outer peripheral member 32h is provided on the outer peripheral side of the planetary carrier 32d. The planetary carrier outer peripheral member 32h is housed along the inner peripheral surface 34a of the gear box 34. The displacement of the planetary gear sets 32, 33 in the direction of the motor axis J is restricted by the planetary carrier outer peripheral member 32h.

[0038] As Figure 3 , 4As shown, a sun gear 33a of a third planetary gear set 33 is integrally formed on the front surface of a carrier 32d of a second planetary gear set 32. The third planetary gear set 33 has four planetary gears 33b, one internal gear 33c, and one carrier 33d. The four planetary gears 33b mesh with the sun gear 33a. A substantially cylindrical gear outer peripheral member 33g is provided on the outer peripheral side of the internal gear 33c, and the gear outer peripheral member 33g has a plurality of convex portions 33h protruding radially outward. The gear outer peripheral member 33g is housed along the inner peripheral surface 34a of a gear case 34. By inserting the plurality of convex portions 33h into engagement recesses 34b of the gear case 34, the internal gear 33c is stopped from rotating relative to the gear case 34.

[0039] As Figure 3 , 4 shown, the four planetary gears 33b also mesh with the internal gear 33c. The four planetary gears 33b are each rotatably supported by a support shaft 33e on the carrier 33d. A washer 33i is sandwiched between the four planetary gears 33b and the internal gear 33c at the rear. A spline groove 33f is provided at the center of the carrier 33d. A spline shaft 23a provided at the rear end of a rotating shaft 23 of a lifting mechanism 22 is inserted into the spline groove 33f. Accordingly, the carrier 33d rotates integrally with the rotating shaft 23. A bearing 35 is provided on the outer peripheral side of the carrier 33d, and the bearing 35 supports the carrier 33d and the rotating shaft 23 so as to be rotatable integrally.

[0040] As Figure 2 shown, the lifting mechanism 22 is provided on the right side portion of a driving machine head 2. The lifting mechanism 22 moves a driver 15 and a piston 14 upward against the air pressure in a pressure accumulating chamber 13. The lifting mechanism 22 has a rotating shaft 23 that can rotate about a motor axis J. A wheel portion 24 is mounted on the rotating shaft 23 so as to be rotatable about the motor axis J. By a rotation direction restricting mechanism 40 (refer to Figure 3 ), rotation of the wheel portion 24 in the counterclockwise direction is permitted when viewed from the front, and rotation in the clockwise direction is restricted. A plurality of engaging portions 25 are provided along the outer peripheral edge of the wheel portion 24. In the present embodiment, for example, seven engaging portions 25 are arranged at intervals in the circumferential direction of the wheel portion 24. The engaging portions 25 are, for example, cylindrical pins extending in the front-rear direction. Each engaging portion 25 moves about the motor axis J by rotation of the wheel portion 24.

[0041] As Figure 2As shown, the left part of the wheel portion 24 enters the driving passage 2a of the driver guide 4 through the window portion 11b provided in the left part of the mechanism housing 11a. Each engaging portion 25 of the wheel portion 24 engages with the bottom of the rack teeth 15a of the driver 15 in the driving passage 2a. In a state where at least one of the engaging portions 25 engages with the bottom of any one of the rack teeth 15a, the wheel portion 24 rotates counterclockwise when viewed from the front. Accordingly, the driver 15 and the piston 14 move upward. By the upward movement of the piston 14, the air pressure in the accumulator chamber 13 increases.

[0042] As Figure 2 shown, a dial-type regulator 28 is provided at the front left of the driver head 2. The regulator 28 has a rotating shaft 28a extending in the vertical direction. The rotating shaft 28a can rotate integrally with the regulator 28 and can move in the vertical direction. A regulator connection portion 3a connected to the regulator 28 is provided at the upper part of the contact arm 3. The contact arm 3 can move integrally with the regulator 28 in the vertical direction. By rotating the regulator 28 about the axis, the vertical position of the contact arm 3 can be adjusted. The regulator 28 has a compression spring 28b disposed on the outer peripheral side of the rotating shaft 28a and supported by the main body housing 11. The compression spring 28b biases the regulator 28 and the contact arm 3 downward.

[0043] As Figure 2 shown, a switch 29 is provided above the regulator 28. When the contact arm 3 moves upward, the regulator 28 presses the protruding pin 29a of the switch 29 through a spring (not shown). Accordingly, the switch 29 becomes on state and sends an on signal to the controller 9. When the on signal is sent to the controller 9, the trigger operation of the trigger 6 is effective (refer to Figure 1 ). When the contact arm 3 is biased downward, the protruding pin 29a of the switch 29 is not pressed. Therefore, the switch 29 does not send an on signal, and the trigger operation of the trigger is ineffective.

[0044] As Figure 1 shown, a substantially rectangular box-shaped magazine 26 is provided behind the driver head 2. The magazine 26 extends straight backward from the driver guide 4. It is set in a substantially rectangular box shape. A plurality of driving members N extending in the vertical direction and arranged in the front-rear direction are loaded in the magazine 26 (refer to Figure 2 ). A pusher 27 for supplying the driving members N to the driving passage 2a is provided inside the magazine 26. The pusher 27 is biased forward by a wound spring (not shown). The front surface of the pusher 27 presses the driving member N accommodated in the front toward the driving passage 2a. Accordingly, the driving members N are supplied one by one from the magazine 26 into the driving passage 2a forward.

[0045] As Figure 3 , 5As shown in FIGS. 6, the rotation direction restricting mechanism 40 has a substantially cylindrical outer ring 41 and a substantially disc-shaped inner peripheral member 42 disposed inside the outer ring 41. In each embodiment of the present disclosure, the outer ring 41 is the outer peripheral member 31g of the carrier of the first planetary gear set 31. In each embodiment of the present disclosure, the inner peripheral member 42 is the carrier 31c of the first planetary gear set 31. The inner peripheral member 42 is received inside the outer ring 41. The inner peripheral surface 41b of the outer ring 41 faces the outer peripheral surface 42a of the inner peripheral member 42 in the radial direction.

[0046] As Figure 3 、 6 shown, the outer peripheral surface 41a of the outer ring 41 faces the inner peripheral surface 34a of the gear box 34 in the radial direction. The length of the inner diameter of the inner peripheral surface 34a of the gear box 34 that does not include the engaging recess 34b is substantially the same as the outer diameter D1 of the internal gear 31b (see Figure 9 ). The outer diameter D2 of the outer peripheral surface 41a of the outer ring 41 that does not include the convex portion 31h is slightly shorter than the outer diameter D1. Therefore, a minute gap is provided between the outer peripheral surface 41a of the outer ring 41 and the inner peripheral surface 34a of the gear box 34.

[0047] As Figure 5 、 6 shown, the rotation direction restricting mechanism 40 has a plurality of cam surfaces 43. The plurality of cam surfaces 43 are recessed radially inward from the outer peripheral surface 42a of the inner peripheral member 42. The plurality of cam surfaces 43 are disposed at substantially equal intervals in the circumferential direction of the outer peripheral surface 42a. For example, six cam surfaces 43 are provided on the outer peripheral surface 42a at intervals of 60° in the circumferential direction. One locking member 44 is inserted into each of the cam surfaces 43. The locking member 44 is, for example, a cylindrical pin having a length substantially the same as the front and rear thicknesses of the inner peripheral member 42. A washer 31j is sandwiched between the inner peripheral member 42 and the locking member 44. Three holes 31k are provided in the washer 31j for inserting three support shafts 31d extending rearward from the inner peripheral member 42.

[0048] As Figures 5 to 7 shown, each of the cam surfaces 43 is disposed asymmetrically in the circumferential direction of the inner peripheral member 42. On the outer peripheral surface 42a, the cam surface 43 on the first direction R1 (counterclockwise when viewed from the front) side is provided as a narrowed portion 43b having a relatively narrow radial width. On the outer peripheral surface 42a, the cam surface 43 on the second direction R2 (clockwise when viewed from the front) side is provided as a widened portion 43a having a relatively wide radial width. The radial width of the widened portion 43a is larger than the diameter of the locking member 44. The radial width of the narrowed portion 43b is smaller than the diameter of the locking member 44.

[0049] As Figure 3 、 6, as shown in FIGS. 9, the rotation direction restricting mechanism 40 has an eccentric mechanism 45 that eccentrically positions the outer ring 41 and the inner peripheral member 42 with respect to each other. In the present embodiment, the eccentric mechanism 45 is a single protrusion 45 that projects radially inward from the inner peripheral surface 34a of the gearbox 34. The length from the tip of the protrusion 45 to the opposite inner peripheral surface 34a of the gearbox 34 is approximately the same as the length of the outer diameter D2 of the outer ring 41. The outer ring 41 is eccentric with respect to the gearbox 34 and the inner peripheral member 42 in the protruding direction of the protrusion 45. Therefore, the center 41c of the inner peripheral surface of the outer ring 41 is offset in the protruding direction of the protrusion 45 with respect to the rotation center 42b of the inner peripheral member 42, i.e., the motor axis J.

[0050] As Figure 3 , 10 shown, the protrusion 45 is provided to have a substantially rectangular shape in a side view. The protrusion 45 is provided only at a position radially laterally aligned with the outer ring 41, and is not provided on the inner peripheral surface 34a of the gearbox 34, for example, in front of or behind the outer ring 41. In the gearbox 34, the respective components of the planetary gear mechanism 30 are assembled in sequence from the bottom surface 34c side of the rear end. The upstream planetary gear 31a and the upstream internal gear 31b located upstream of the outer ring 41 in the power transmission direction are assembled to the gearbox 34 before the outer ring 41. The gearbox 34 is made of a resin that is easily elastically deformable, and the protruding length of the protrusion 45 is very small. Therefore, the upstream internal gear 31b can be assembled over the protrusion 45. The upstream internal gear 31b assembled to the gearbox 34 is held in a rear position where it does not interfere with the protrusion 45.

[0051] As Figure 3 shown, the downstream planetary gear 32b and the downstream internal gear 32c located downstream of the outer ring 41 in the power transmission direction are assembled to the gearbox 34 after the outer ring 41. The downstream internal gear 32c assembled to the gearbox 34 is held in a front position where it does not interfere with the protrusion 45.

[0052] As Figures 6 to 8 shown, by eccentrically positioning the outer ring 41 and the inner peripheral member 42 with respect to each other, the radial distance between the cam surface 43 and the inner peripheral surface 41b of the outer ring 41 is of different sizes for each cam surface 43. Specifically, the radial distance between the cam surface 43 on the side where the protrusion 45 is provided (left side in the figure) and the inner peripheral surface 41b of the outer ring 41 becomes smaller. The radial distance between the cam surface 43 on the side opposite to the protrusion 45 (right side in the figure) and the inner peripheral surface 41b of the outer ring 41 becomes larger.

[0053] As Figure 6As shown in FIG. 1 , when the inner peripheral member 42 rotates in the first direction R1, the locking member 44 moves toward the widened portion 43a in all the cam surfaces 43. Therefore, there is a gap between all the locking members 44 and the inner peripheral surface 41b of the outer ring 41. Therefore, the locking member 44 does not prevent the inner peripheral member 42 from rotating in the first direction R1. Accordingly, the inner peripheral member 42 is allowed to rotate in the first direction R1.

[0054] like Figure 7 , 8 As shown in FIG. 1 , when the inner peripheral member 42 wants to rotate in the second direction R2, the locking member 44 moves to the narrowed portion 43b side in the cam surface 43. In particular, in the cam surface 43 located on the side (left side in the figure) where the protrusion 45 protrudes, the locking member 44 bites between the cam surface 43 and the inner peripheral surface 41b of the outer ring 41. For example, when there are three or more locking members 44 biting between the cam surface 43 and the inner peripheral surface 41b of the outer ring 41, the rotation of the inner peripheral member 42 is restricted. More specifically, the rotation center 42b of the inner peripheral member 42 is located inside the triangle formed by the three locking members 44 biting into the three cam surfaces 43, thereby restricting the rotation of the inner peripheral member 42 in the second direction R2. In this way, by eccentricating the outer ring 41 and the inner peripheral member 42, the number of locking members 44 that can reliably bite between the cam surface 43 and the inner peripheral surface 41b of the outer ring 41 can be increased. According to this, the rotation of the inner peripheral member 42 in the second direction R2 can be restricted more reliably.

[0055] Next, refer to Figures 1 to 3 A series of processes of the driving action of the electric tool 1 are explained. The driver 15 in the standby position stops slightly below the top dead center. When the driver 15 is in the standby position, the bottom surface of the rack teeth 15a at the lower end engages with the final engaging portion 25a of the lifting mechanism 22. The contact arm 3 moves upward when pressed by the driven workpiece W. The regulator 28 moves upward in conjunction with the contact arm 3, pressing the protruding pin 29a of the switch 29. The switch 29 sends an on signal to the controller 9. The controller 9 starts the motor 20 when receiving the on signal from the switch 29 and pulling the trigger 6. When the motor 20 is started, the wheel portion 24 of the lifting mechanism 22 rotates. The final engaging portion 25a causes the rack teeth 15a at the lower end to move upward. Accordingly, the driver 15 moves upward from the standby position to the top dead center.

[0056] In a state where the driver 15 stops at the standby position, the tip 15b of the driver 15 overlaps with the head of the foremost driving element N in the front-rear direction. Therefore, the driving element N is not loaded in the driving path 2a. When the tip 15b of the driver 15 moves to a position above the head of the foremost driving element N, the foremost driving element N is loaded into the driving path. When the driver 15 moves upward to the top dead center and reaches the state just before driving, by the rotation of the wheel portion 24, the final engaging portion 25a disengages from the bottom of the lowermost rack tooth 15a. The driver 15 is urged downward by the air pressure applied to the accumulator chamber 13 of the piston 14. The tip 15b of the driver 15 moves downward to strike the driving element N in the driving path 2a. The struck driving element N is ejected from the ejection port 2b toward the work piece W. When the driver 15 moves downward, all the engaging portions 25 retract to a position to the right of the driving path 2a. Therefore, interference between the rack tooth 15a of the downward-moving driver 15 and the engaging portion 25 is avoided, and the driving operation is smoothly performed.

[0057] The wheel portion 24 continues to rotate during the downward movement of the driver 15 and after reaching the bottom dead center. When the driver 15 is at the bottom dead center and the wheel portion 24 rotates to a specified rotation angle, one of the engaging portions 25 engages with the bottom of the uppermost rack tooth 15a. Accordingly, the return operation for moving the driver 15 upward is started. When the final engaging portion 25a engages with the bottom of the lowermost rack tooth 15a, the driver 15 returns to the standby position. For example, by appropriately measuring the time from the start of the motor 20 or appropriately measuring the rotation position of the wheel portion 24, the motor 20 is stopped at the stage when the piston 14 reaches the standby position. Accordingly, the driver 15 is held at the standby position. Thus, a series of driving operations are completed.

[0058] As described above, the power tool 1 is as Figures 6 to 8 shown and has a motor 20 (refer to Figure 3 ). The power tool 1 has a rotation direction restricting mechanism 40 that restricts the rotation direction of the rotation driven by the output of the motor 20. The rotation direction restricting mechanism 40 has an outer ring 41. The rotation direction restricting mechanism 40 has an inner peripheral member 42 provided on the inner peripheral side of the outer ring 41. The rotation direction restricting mechanism 40 has a plurality of cam surfaces 43 recessed in the outer peripheral surface 42a of the inner peripheral member 42. The rotation direction restricting mechanism 40 has a locking member 44 that is movably arranged within the cam surface 43, allows rotation in the relative first direction R1 of the outer ring 41 and the inner peripheral member 42, and restricts rotation in the relative second direction R2. The rotation direction restricting mechanism 40 has a projection (eccentric mechanism) 45 that eccentrically positions the outer ring 41 and the inner peripheral member 42 with respect to each other.

[0059] Therefore, the outer ring 41 and the inner peripheral member 42 are eccentric to each other by the protrusion 45. As a result, a part of the plurality of cam surfaces 43 is disposed at a position where the outer ring 41 and the inner peripheral member 42 are in close contact with each other in the radial direction. Therefore, at least a part of the locking members 44 inserted into the cam surfaces 43 can be in close contact with both the outer ring 41 and the inner peripheral member 42. Therefore, when the outer ring 41 and the inner peripheral member 42 are about to rotate relative to each other in the second direction R2, the locking members 44 are reliably clamped between the outer ring 41 and the inner peripheral member 42. Accordingly, the relative rotational direction of the outer ring 41 and the inner peripheral member 42 can be more reliably restricted to one direction.

[0060] As Figure 3 , Figures 6 to 8 shown, the power tool 1 has a gear box (holding member) 34 that surrounds the outer ring 41. A protrusion 45 serving as an eccentric mechanism that protrudes toward the other and abuts against the other is provided on one of the outer ring 41 and the gear box 34. Therefore, the outer ring 41 and the inner peripheral member 42 can be made eccentric to each other by a simple structure in which the protrusion 45 is provided on the outer ring 41 or the gear box 34. Therefore, the rotation direction restricting mechanism 40 can be provided without significant changes compared to the existing structure, and the rotation direction can be more reliably restricted to one direction.

[0061] As Figures 5 to 8 shown, the cam surface 43 is provided on the inner peripheral member 42. Therefore, when the inner peripheral member 42 rotates, the locking member 44 can be smoothly moved along the cam surface 43 by centrifugal force. Accordingly, rotation in the first direction R1 can be more reliably allowed and rotation in the second direction R2 can be restricted.

[0062] As Figure 3 , Figures 6 to 8 shown, the power tool 1 has a gear box (holding member) 34 that surrounds the outer ring 41 and restricts the rotation of the outer ring 41. The inner peripheral member 42 can be rotated by the motor 20. Therefore, the outer ring 41 is provided so as not to rotate integrally with the gear box 34, and the inner peripheral member 42 is provided as a component that rotates by the output of the motor 20. Accordingly, for example, the rotation direction restricting mechanism 40 can be provided in a gear train or the like that converts and transmits the output of the motor 20.

[0063] As Figure 3 shown, the power tool 1 has a planetary gear mechanism 30 that decelerates the rotation based on the output of the motor 20. The planetary gear mechanism 30 has a planetary gear 31a rotatably held by the inner peripheral member 42. Therefore, the rotation direction restricting mechanism 40 that can more reliably restrict the rotation direction to one direction can be provided in the planetary gear mechanism 30 with a large number of components and a small space.

[0064] As Figure 3 ,4 As shown in Fig. 9, the planetary gear mechanism 30 has an internal gear 31b that engages with the planetary gear 31a. The internal gear 31b and the outer ring 41 are arranged and housed in the gearbox 34. The outer diameter D2 of the outer ring 41 is smaller than the outer diameter D1 of the internal gear 31b. Therefore, by making the outer diameter D2 of the outer ring 41 smaller than the outer diameter D1 of the internal gear 31b, a gap can be provided between the outer diameter D2 of the outer ring 41 and the inner peripheral surface 34a of the gearbox 34. The center of the internal gear 31b is located at the center of the gearbox 34. Therefore, the outer ring 41 can be eccentric with respect to the center of the internal gear 31b using the gap.

[0065] As Figure 3 shown, the power tool 1 has a planetary gear mechanism 30 that decelerates the rotation based on the output of the motor 20. The planetary gear mechanism 30 has an upstream internal gear 31b. The planetary gear mechanism 30 has an upstream planetary gear 31a that engages with the upstream internal gear 31b. The planetary gear mechanism 30 has a downstream internal gear 32c. The planetary gear mechanism 30 has a downstream planetary gear 32b that engages with the downstream internal gear 32c. The upstream internal gear 31b, the outer ring 41, and the downstream internal gear 32c are sequentially housed in the gearbox 34. A protrusion 45 serving as an eccentric mechanism that protrudes toward the outer ring 41 and abuts against the outer ring 41 is provided on the gearbox 34. The protrusion 45 makes a part of the inner diameter of the gearbox 34 smaller than the outer diameter D1 of the upstream internal gear 31b and the outer diameter D1 of the downstream internal gear 32c (see Figure 9 ).

[0066] Therefore, the outer ring 41 can be assembled together with the components of the planetary gear mechanism 30 into the gearbox 34. Moreover, the protrusion 45 of the gearbox 34 is provided so as not to interfere with components other than the outer ring 41, such as the upstream internal gear 31b and the downstream internal gear 32c. In this way, while not interfering with the drive of the planetary gear mechanism 30, only the outer ring 41 can be eccentric with respect to the motor axis J, which is the rotation center 42b of the inner peripheral component 42.

[0067] As Figure 2 , 3 shown, the power tool 1 has a lifting mechanism 22 that stores energy through the output of the motor 20. The power tool 1 has a driver 15 that moves in the driving direction by the energy stored by the lifting mechanism 22 to drive a driving member N. Therefore, the lifting mechanism 22 stores energy by rotating forward. If the lifting mechanism 22 rotates backward due to the stored energy, the stored energy is lost and a normal driving operation cannot be performed. By allowing the rotation direction of the lifting mechanism 22 to be only the forward rotation direction by the rotation direction restricting mechanism 40, the inadvertent loss of the stored energy can be suppressed.

[0068] As Figure 3As shown, the power tool 1 has a planetary gear mechanism 30 that decelerates the rotation based on the output of the motor 20. The planetary gear mechanism 30 has an upstream internal gear 31b. The planetary gear mechanism 30 has an upstream planetary gear 31a that engages with the upstream internal gear 31b. The planetary gear mechanism 30 has a downstream internal gear 32c. The planetary gear mechanism 30 has a downstream planetary gear 32b that engages with the downstream internal gear 32c. The downstream internal gear 32c is provided on the downstream side of the rotation direction restricting mechanism 40. Therefore, at the downstream internal gear 32c on the downstream side of the rotation direction restricting mechanism 40, the output of the motor 20 is decelerated. Therefore, at a stage where the output torque is still small, the rotation direction can be restricted to one direction by the rotation direction restricting mechanism 40. Accordingly, the rotation direction restricting mechanism 40 can more reliably restrict the rotation direction.

[0069] Next, according to Figure 11 a second embodiment of the present disclosure will be described. The power tool 50 of the second embodiment has a rotation direction restricting mechanism 51 that replaces Figure 6 the rotation direction restricting mechanism 40 shown. In the following description, only the parts different from the first embodiment will be described in detail. The rotation direction restricting mechanism 51 has a planetary carrier outer peripheral member 31g as an outer ring 52. The rotation direction restricting mechanism 51 has a planetary carrier 31c as an inner peripheral member 53. A plurality of cam surfaces 54 are provided on the outer peripheral surface 53a of the inner peripheral member 53. One locking member 55 is inserted into each of the cam surfaces 54. The inner peripheral member 53, the outer peripheral surface 53a, and the rotation center 53b are provided in the same manner as Figure 6 the inner peripheral member 42, the outer peripheral surface 42a, and the rotation center 42b shown. The cam surfaces 54, the widened portion 54a, the narrowed portion 54b, and the locking member 55 are provided in the same manner as Figure 6 the cam surfaces 43, the widened portion 43a, the narrowed portion 43b, and the locking member 44 shown.

[0070] As Figure 11 shown, the outer peripheral surface 52a and the inner peripheral surface 52b of the outer ring 52 are eccentric to each other. The inner peripheral center 52d of the inner peripheral surface 52b is offset to the right in the drawing with respect to the outer peripheral center 52c of the outer peripheral surface 52a. The rotation center 53b of the inner peripheral member 53 is located at the same position as the outer peripheral center 52c of the outer peripheral surface 52a. Therefore, the inner peripheral surface 52b of the outer ring 52 is eccentric with respect to the rotation center 53b of the inner peripheral member 53. Therefore, in the drawing, the radial interval between the left cam surface 54 and the inner peripheral surface 52b of the outer ring 52 becomes smaller. In the drawing, the radial interval between the right cam surface 54 and the inner peripheral surface 52b of the outer ring 52 becomes larger. Accordingly, the rotation direction restricting mechanism 51 operates in the same manner as Figures 6 to 8 the rotation direction restricting mechanism 40 shown.

[0071] AsFigure 11 As shown, when the inner peripheral member 53 rotates in the first direction R1, all the locking members 55 move toward the widening portion 54a within all the cam surfaces 54. Accordingly, all the locking members 55 have a gap between the inner peripheral surface 52b of the outer ring 52. Thereby, the locking members 55 do not impede the rotation of the inner peripheral member 53 in the first direction R1. When the inner peripheral member 53 attempts to rotate in the second direction R2, the locking members 55 move toward the narrowing portion 54b within the cam surfaces 54. For example, among at least three cam surfaces 54, the locking members 55 bite into the space between the cam surfaces 54 and the inner peripheral surface 52b of the outer ring 52. Thereby, the rotation of the inner peripheral member 53 in the second direction R2 can be more reliably restricted.

[0072] As described above, as Figure 11 shown, the inner peripheral member 53 can be rotated by the motor 20 (refer to Figure 3 ). The outer ring 52 has an inner peripheral surface 52b that is eccentric with respect to the rotation center 53b of the inner peripheral member 53. Thus, for example, when the inner peripheral member 53 rotates, the inner peripheral surface 52b of the outer ring 52 and the outer peripheral surface 53a of the inner peripheral member 53 can be made eccentric to each other while making the inner peripheral member 53 axisymmetric. Therefore, the wobbling of the inner peripheral member 53 can be suppressed, and the rotation direction can be more reliably restricted to one direction.

[0073] Next, a third embodiment of the present disclosure will be described according to Figure 12 . The power tool 60 of the third embodiment has a rotation direction restricting mechanism 61 that replaces the Figure 6 shown rotation direction restricting mechanism 40. In the following description, only the parts different from the first embodiment will be described in detail. The rotation direction restricting mechanism 61 has a planet carrier outer peripheral member 31g as the outer ring 62. The rotation direction restricting mechanism 61 has a planet carrier 31c as the inner peripheral member 63. A plurality of cam surfaces 64 are provided on the outer peripheral surface 63a of the inner peripheral member 63. One locking member 65 is inserted into each of the cam surfaces 64. The outer ring 62, the outer peripheral surface 62a, and the inner peripheral surface 62b are provided in the same manner as the Figure 6 shown outer ring 41, the outer peripheral surface 41a, and the inner peripheral surface 41b. The cam surfaces 64, the widening portion 64a, the narrowing portion 64b, and the locking members 65 are provided in the same manner as the Figure 6 shown cam surfaces 43, the widening portion 43a, the narrowing portion 43b, and the locking members 44.

[0074] As Figure 12As shown, the outer peripheral surface 63a of the inner peripheral member 63 is eccentric with respect to the rotation center 63b. The eccentric center 63c of the outer peripheral surface 63a is offset to the left in the drawing with respect to the rotation center 63b. The inner peripheral surface 62b of the outer ring 62 is arranged around the rotation center 63b of the inner peripheral member 63. Therefore, in the drawing, the radial interval between the left cam surface 64 and the inner peripheral surface 62b of the outer ring 62 becomes smaller. In the drawing, the radial interval between the right cam surface 64 and the inner peripheral surface 62b of the outer ring 62 becomes larger. Accordingly, the rotation direction restricting mechanism 61 operates in the same manner as Figures 6 to 8 the rotation direction restricting mechanism 40 shown.

[0075] As Figure 12 shown, when the inner peripheral member 63 rotates in the first direction R1, the locking members 65 move toward the widening portion 64a side within all the cam surfaces 64. Therefore, all the locking members 65 have a gap with the inner peripheral surface 62b of the outer ring 62. Accordingly, the locking members 65 do not hinder the rotation of the inner peripheral member 63 in the first direction R1. When the inner peripheral member 63 attempts to rotate in the second direction R2, the locking members 65 move toward the narrowing portion 64b side within the cam surfaces 64. For example, among at least three cam surfaces 64, the locking members 65 bite into the space between the cam surfaces 64 and the inner peripheral surface 62b of the outer ring 62. Accordingly, the rotation of the inner peripheral member 63 in the second direction R2 can be restricted more reliably.

[0076] As described above, as Figure 12 shown, the inner peripheral member 63 can be rotated by the motor 20 (refer to Figure 3 ). The inner peripheral member 63 has an outer peripheral surface 63a that is eccentric with respect to the rotation center 63b of the inner peripheral member 63. Therefore, the outer ring 62 can be assembled in the same manner as the existing structure, and the inner peripheral surface 62b of the outer ring 62 and the outer peripheral surface 63a of the inner peripheral member 63 can be made eccentric with respect to each other, thereby restricting the rotation direction to one direction more reliably.

[0077] Next, a fourth embodiment of the present disclosure will be described according to Figure 13 . The power tool 70 of the fourth embodiment has a rotation direction restricting mechanism 71 that replaces the Figure 6 rotation direction restricting mechanism 40 shown. In the following description, only the parts different from the first embodiment will be described in detail. The rotation direction restricting mechanism 71 has a carrier outer peripheral member 31g as the outer ring 72. The rotation direction restricting mechanism 71 has a carrier 31c as the inner peripheral member 73. One protrusion (eccentric mechanism) 76 that protrudes radially inward is provided on the inner peripheral surface 34a of the gear box 34. The protrusion 76 is provided in the same manner as the Figure 6 protrusion 45 shown. The rotation direction restricting mechanism 71 has a locking member 75 that is provided in the same manner as the locking member 44 (refer to Figure 6 ).

[0078] As shown Figure 13 in FIG. 1, the inner peripheral member 73 is not provided with a cam surface and is formed into a disc shape. The outer peripheral surface 73a of the inner peripheral member 73 is formed as an arc surface centered on the rotation center 73b. The outer peripheral surface 72a and the inner peripheral surface 72b of the outer ring 72 extend in an arc shape centered on the inner peripheral surface center 72c. A plurality of cam surfaces 74 are provided on the inner peripheral surface 72b of the outer ring 72. The cam surfaces 74 are recessed toward the radially outer side. The plurality of cam surfaces 74 are provided at substantially equal intervals in the circumferential direction of the inner peripheral surface 72b. For example, six cam surfaces 74 are provided on the inner peripheral surface 72b at intervals of 60° in the circumferential direction. One locking member 75 is inserted into each of the cam surfaces 74.

[0079] As shown Figure 13 in FIG. 2, the respective cam surfaces 74 are provided asymmetrically in the circumferential direction of the outer ring 72. In the inner peripheral surface 72b, the cam surface 74 on the first direction R1 (counterclockwise direction when viewed from the front) side is provided as a widened portion 74a having a wider radial width. In the inner peripheral surface 72b, the cam surface 74 on the second direction R2 (clockwise direction when viewed from the front) side is provided as a narrowed portion 74b having a narrower radial width. The radial width of the widened portion 74a is larger than the diameter of the locking member 75. The radial width of the narrowed portion 74b is smaller than the diameter of the locking member 75.

[0080] As shown Figure 13 in FIG. 3, the inner peripheral surface 72b of the outer ring 72 is eccentric with respect to the outer peripheral surface 73a of the inner peripheral member 73 by means of a protrusion 76. The inner peripheral surface center 72c of the outer ring 72 is offset to the right in the drawing with respect to the rotation center 73b of the inner peripheral member 73. Therefore, in the drawing, the radial interval between the left cam surface 74 and the outer peripheral surface 73a of the inner peripheral member 73 becomes smaller. In the drawing, the radial interval between the right cam surface 74 and the outer peripheral surface 73a of the inner peripheral member 73 becomes larger. Accordingly, the rotation direction restricting mechanism 71 operates in the same manner as the rotation direction restricting mechanism 40 Figures 6 to 8 shown in FIG. 4.

[0081] As shown Figure 13 in FIG. 5, when the inner peripheral member 73 rotates in the first direction R1, the locking members 75 move toward the widened portion 74a side within all the cam surfaces 74. Therefore, all the locking members 75 have a gap with the outer peripheral surface 73a of the inner peripheral member 73. Accordingly, the locking members 75 do not hinder the rotation of the inner peripheral member 73 in the first direction R1. When the inner peripheral member 73 attempts to rotate in the second direction R2, the locking members 75 move toward the narrowed portion 74b side within the cam surfaces 74. For example, in at least three cam surfaces 74, the locking members 75 bite between the cam surfaces 74 and the outer peripheral surface 73a of the inner peripheral member 73. Accordingly, the rotation of the inner peripheral member 73 in the second direction R2 can be restricted more reliably.

[0082] As described above, the power tool 70 is as follows Figure 13 shown and has a motor 20 (see Figure 3 ). The power tool 70 has a rotation direction restricting mechanism 71 that restricts the rotation direction of the rotation caused by the output of the motor 20. The rotation direction restricting mechanism 71 has an outer ring 72. The rotation direction restricting mechanism 71 has an inner peripheral member 73 provided on the inner peripheral side of the outer ring 72. The rotation direction restricting mechanism 71 has a cam surface 74 recessed in the inner peripheral surface 72b of the outer ring 72. The rotation direction restricting mechanism 71 has a locking member 75 that is movably disposed within the cam surface 74, allows rotation in the relative first direction R1 of the outer ring 72 and the inner peripheral member 73, and restricts rotation in the relative second direction R2. The rotation direction restricting mechanism 71 has a projection (eccentric mechanism) 76 that eccentrically positions the outer ring 72 and the inner peripheral member 73 with respect to each other.

[0083] Therefore, the outer ring 72 and the inner peripheral member 73 are eccentric with respect to each other by the projection 76, whereby a part of the plurality of cam surfaces 74 is disposed at a position where the outer ring 72 and the inner peripheral member 73 are in close contact with each other in the radial direction. Therefore, at least a part of the locking members 75 inserted into the cam surface 74 can be in close contact with both the outer ring 72 and the inner peripheral member 73. Therefore, when the outer ring 72 and the inner peripheral member 73 are about to rotate relative to each other in the second direction R2, the locking member 75 is reliably clamped between the outer ring 72 and the inner peripheral member 73. Accordingly, the relative rotation direction of the outer ring 72 and the inner peripheral member 73 can be more reliably restricted to one direction.

[0084] Various modifications can be applied to the power tools 1, 50, 60, and 70 of the embodiments described above. As the power tool, a pneumatic spring type driving tool is exemplified. Instead of this, for example, the present disclosure can also be applied to power tools such as a ratchet, a screwdriver, a caulking gun, and a reciprocating saw that have a power transmission path in which the rotation direction is desired to be restricted to one direction.

[0085] The number of the cam surfaces and the locking members is not limited to the exemplified number and can be appropriately changed. A structure in which a rotation direction restricting mechanism is provided in the planetary gear mechanism 30 is exemplified. Instead of this, for example, a rotation direction restricting mechanism can also be provided in a reduction gear set that does not have a planetary gear set. A structure in which a rotation direction restricting mechanism is provided in the planetary gear mechanism 30 having a three-stage planetary gear set is exemplified. Instead of this, for example, a rotation direction restricting mechanism can also be provided in a planetary gear mechanism having a two-stage or four-stage or more planetary gear set.

[0086] Illustrated is a structure in which a rotation direction restricting mechanism is provided between the carrier 31c of the first planetary gear set 31 and the outer peripheral member 31g of the carrier. Instead of this, for example, a rotation direction restricting mechanism may be provided between the carrier 32d of the second planetary gear set 32 and the outer peripheral member 31g. Since there is a third planetary gear set 33 on the downstream side of the second planetary gear set 32, the torque is not increased to the maximum in the second planetary gear set 32. Therefore, the load applied to the rotation direction restricting mechanism when restricting the rotation in the second direction R2 is not large enough. Therefore, the effect of restricting the rotation direction is sufficient.

[0087] Illustrated is a structure in which the inner peripheral member rotates about the axis and the outer ring is held in a non-rotating manner in the gear case 34. Instead of this, for example, it may be a structure in which the outer ring can rotate about the axis and the inner peripheral member is held in a non-rotating manner. Alternatively, it may be a structure in which the inner peripheral member and the outer ring can each rotate about the axis and the relative rotational positions of the two change.

Claims

1. An electric tool, characterized in that: A motor and a rotation direction limiting mechanism are provided, wherein the rotation direction limiting mechanism limits the rotation direction of the motor output. The rotation direction limiting mechanism comprises an outer ring, an inner peripheral component, a plurality of cam surfaces, a locking component and an eccentric mechanism, wherein: The inner peripheral component is arranged on the inner peripheral side of the outer ring; A plurality of cam surfaces are recessedly disposed on the inner peripheral surface of the outer ring or the outer peripheral surface of the inner peripheral component; The locking member is movably disposed in the cam surface, allowing the outer ring and the inner peripheral member to rotate relative to each other in a first direction and restricting rotation relative to each other in a second direction; The eccentric mechanism causes the outer ring and the inner peripheral member to be eccentric with each other.

2. The electric tool according to claim 1, characterized in that: having a retaining member surrounding the outer ring, One of the outer ring and the holding member is provided with a protrusion as the eccentric mechanism that protrudes toward the other and contacts the other.

3. The electric tool according to claim 1, characterized in that: The inner peripheral member can be rotated by the motor, The outer ring has the inner peripheral surface that is eccentric with respect to the rotation center of the inner peripheral member.

4. The electric tool according to claim 1, characterized in that: The inner peripheral member can be rotated by the motor, The inner peripheral member has an outer peripheral surface that is eccentric with respect to a rotation center of the inner peripheral member.

5. The electric tool according to any one of claims 1 to 4, characterized in that: The cam surface is provided on the inner peripheral component.

6. The electric tool according to any one of claims 1 to 5, characterized in that: A retaining member is provided which surrounds the outer ring and restricts the rotation of the outer ring. The inner peripheral member is rotatable by the motor.

7. The electric tool according to any one of claims 1 to 6, characterized in that: A planetary gear mechanism is provided for reducing the speed of rotation based on the output of the motor. The planetary gear mechanism includes a planetary gear rotatably held on the inner peripheral member.

8. The electric tool according to claim 7, characterized in that: The planetary gear mechanism includes an internal gear engaged with the planetary gear. The inner gear and the outer ring are arranged in parallel and housed in a gear box. The outer diameter of the outer ring is smaller than the outer diameter of the inner gear.

9. The electric tool according to any one of claims 1 to 8, characterized in that: A planetary gear mechanism is provided for reducing the speed of rotation based on the output of the motor. The planetary gear mechanism includes an upstream internal gear, an upstream planetary gear engaged with the upstream internal gear, a downstream internal gear, and a downstream planetary gear engaged with the downstream internal gear. The upstream internal gear, the outer ring, and the downstream internal gear are sequentially housed in a gear box. The gear box is provided with a protrusion as the eccentric mechanism which protrudes toward the outer ring and abuts against the outer ring. The protrusion makes a portion of the inner diameter of the gear case smaller than the outer diameters of the upstream side internal gear and the downstream side internal gear.

10. The electric tool according to any one of claims 1 to 9, characterized in that: It has a lifting mechanism and a driver, wherein: The lifting mechanism accumulates energy through the output of the motor; The driver drives the driven object by moving in a driving direction using the energy accumulated in the lifting mechanism.

11. The electric tool according to any one of claims 1 to 10, characterized in that: A planetary gear mechanism is provided for reducing the speed of rotation based on the output of the motor. The planetary gear mechanism includes an upstream internal gear, an upstream planetary gear engaged with the upstream internal gear, a downstream internal gear, and a downstream planetary gear engaged with the downstream internal gear. The downstream side internal gear is provided on the downstream side of the rotation direction restricting mechanism.

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