JP7773100B2 - Work equipment - Google Patents

Description

The present invention relates to a work machine.

Patent Documents 1 and 2 below disclose work machines such as driver drills. Patent Document 3 below discloses a work machine with a detachable handle.

A work machine such as a driver drill comprises a motor, a spindle, a transmission mechanism that transmits the rotation of the motor to the spindle, a chuck screwed to the spindle, a reduction ratio switching mechanism that switches the reduction ratio of the transmission mechanism, and a clutch mechanism that cuts off the transmission of rotation from the transmission mechanism to the spindle at a predetermined torque.

The reduction ratio switching mechanism has a shift knob operated by the user and a shift arm that moves the slide ring gear of the transmission mechanism forward and backward in response to the operation of the shift knob. The clutch mechanism has a clutch dial that allows the user to change the specified torque. Driver drills with a vibration function, such as those described in Patent Document 2, are also called vibration driver drills, and the on/off state of vibration can be switched on or off by operating the clutch dial.

Japanese Patent Application Laid-Open No. 2014-018914 Japanese Patent Application Laid-Open No. 2015-191735 Japanese Patent Application Laid-Open No. 2017-80853

In work machines such as driver drills, the chuck and spindle are fixed with high torque, and a special jig is required to release the fixation. In other words, without a special jig, the chuck and spindle essentially become a single tool holder. This makes it difficult to replace parts that cannot be removed without releasing the fixation between the chuck and spindle. Conventional work machines have many parts that are difficult to replace, making them difficult to repair. The first challenge recognized by the inventor is to provide a work machine that is easy to repair.

Working machines such as driver drills can be placed in drill mode, which provides maximum torque, by immobilizing the ring gear of the transmission mechanism. One configuration for entering drill mode involves pushing a stopper pin toward the ring gear using a nut that rotates with the clutch dial and moves axially. Depending on the rotational position of the ring gear, part of the ring gear may be located on the extension of the stopper pin. With the above configuration, if the stopper pin hits this part, the clutch dial cannot be turned, making it impossible to switch to drill mode, resulting in poor usability. The second problem recognized by the inventor is to provide a working machine that can prevent problems that prevent the ring gear from being immobilized.

In a work machine such as a driver drill, where the transmission mechanism is housed in multiple cases separated in the front-to-rear direction, the multiple cases can be fixed in the front-to-rear direction with fixing parts such as screws to increase the rigidity of the case and suppress deformation. However, if the shift arm passes outside the fixing parts in the radial direction of the case, the product will become larger in the radial direction. The third challenge recognized by the inventor is to provide a work machine that can suppress size increase.

In work machines such as vibration driver drills, if the clutch dial requires a large amount of operation to switch between vibration and non-vibration, switching between vibration and non-vibration is time-consuming and results in poor workability. The fourth problem recognized by the inventors is to provide a work machine that can reduce the time required to switch between vibration and non-vibration.

A known configuration of a handle that can be attached to or detached from a work machine is one in which the handle is attached to the work machine by closing the gap in an annular mounting section that has a gap (opening) in part of its circumference. In this configuration, if the maximum length of the mounting section gap is its natural length, it can be difficult to attach or detach the handle. The fifth problem recognized by the inventor is to provide a handle that can be easily attached or detached to or from a work machine, and a work machine equipped with a handle that can be easily attached or detached.

If the handle cannot be moved while attached to a work machine, it is not possible to fine-tune the attachment state of the handle, which can be inconvenient. The sixth problem recognized by the inventor is to provide a handle whose attachment state to a work machine can be fine-tuned, and a work machine equipped with a handle whose attachment state can be fine-tuned.

The object of the present invention is to provide a work machine that solves at least the third of the above problems.

One aspect of the present invention is a work machine.
A motor;
a tool holder located on one side of the motor in an axial direction of the motor;
a transmission unit including a transmission mechanism including a gear that transmits rotation of the motor to the tool bit holder, and a transmission unit housing that accommodates the transmission mechanism;
a reduction ratio switching unit that switches the reduction ratio of the transmission mechanism,
The transmission housing includes:
a first case including a cylindrical case having an opening on the other side in the axial direction, and a cover that holds a motor bearing portion that supports a shaft of the motor and closes the opening of the cylindrical case ;
a second case located on one side of the first case in the axial direction,
a first fixing portion extending in the axial direction and fixing the cover of the first case and the second case from the other side in the axial direction ;
a gap is formed between an outer surface of the cylindrical case of the first case and the first fixing portion when the lid of the first case and the second case are fixed by the first fixing portion;
A portion of the reduction ratio changeover portion extends into the gap.

The present invention may also be expressed as an "electric work machine," "power tool," "electrical equipment," etc., and such expressions are also valid aspects of the present invention.

According to the present invention, it is possible to provide a work machine that solves at least the third of the above problems.

1 is a perspective view of a work machine 1 according to an embodiment of the present invention, viewed from the front side; FIG. 2 is a perspective view of the work machine 1 as seen from the rear side. FIG. FIG. FIG. 2 is an enlarged right cross-sectional view showing the configuration of a transmission/output component 4 of the work machine 1. FIG. 2 is an exploded perspective view of the transmission/output component 4, seen from the front side. FIG. 2 is an exploded perspective view of the transmission/output component 4, seen from the rear side. (A) is a perspective view of the rear case 60 appearing in Figures 5 to 7, as seen from the front side. (B) is a perspective view of the rear case 60 as seen from the rear side. (C) is a front view of the rear case 60. (D) is a cross-sectional view taken along line A-A in Figure 8(C). (E) is a cross-sectional view taken along line B-B in Figure 8(C). (F) is a rear view of the rear case 60. (G) is a right side view of the rear case 60. (A) is a perspective view of the final ring gear 90 appearing in Figures 5 to 7, as seen from the front side. (B) is a perspective view of the final ring gear 90, as seen from the rear side. (C) is a front view of the final ring gear 90. (D) is a cross-sectional view taken along line A-A in Figure 9(C). (E) is a cross-sectional view taken along line B-B in Figure 9(C). (F) is a rear view of the final ring gear 90. (G) is a right side view of the final ring gear 90. 10(A) to 10(D) are perspective views of the stopper block 120 appearing in Figures 5 to 7, viewed from different viewpoints. (E) is a front view of the stopper block 120. (F) is a cross-sectional view taken along line A-A in Figure 10(E). (G) is a rear view of the stopper block 120. (G) is a right side view of the stopper block 120. 11A is a perspective view of the gear case 140 that appears in Figures 5 to 7. (B) is a front view of the gear case 140. (C) is a cross-sectional view taken along line A-A in Figure 11B. (D) is a rear view of the gear case 140. (E) is a right side view of the gear case 140. (A) is a perspective view of the rear stopper cam ring 210 appearing in Figures 5 to 7, as seen from the front side. (B) is a perspective view of the rear stopper cam ring 210, as seen from the rear side. (C) is a front view of the rear stopper cam ring 210. (D) is a cross-sectional view taken along line A-A in Figure 12(C). (E) is a cross-sectional view taken along line B-B in Figure 12(C). (F) is a rear view of the rear stopper cam ring 210. (G) is a right side view of the rear stopper cam ring 210. (A) is a perspective view of the front stopper cam ring 230 appearing in Figures 5 to 7, as seen from the front side. (B) is a perspective view of the front stopper cam ring 230 as seen from the rear side. (C) is a front view of the front stopper cam ring 230. (D) is a cross-sectional view taken along line A-A in Figure 13(C). (E) is a cross-sectional view taken along line B-B in Figure 13(C). (F) is a rear view of the front stopper cam ring 230. (G) is a right side view of the front stopper cam ring 230. 14A is a perspective view of the nut 260 that appears in Figures 5 to 7. (B) is a front view of the nut 260. (C) is a cross-sectional view taken along line A-A in Figure 14B. (D) is a rear view of the nut 260. (E) is a right side view of the nut 260. (A) is a perspective view of the ratchet cam ring 280 appearing in Figures 5 to 7, as seen from the front. (B) is a perspective view of the ratchet cam ring 280 as seen from the rear. (C) is a front view of the ratchet cam ring 280. (D) is a cross-sectional view taken along line A-A in Figure 15(C). (E) is a cross-sectional view taken along line B-B in Figure 15(C). (F) is a rear view of the ratchet cam ring 280. (G) is a right side view of the ratchet cam ring 280. (A) is a perspective view of the clutch dial 300 appearing in Figures 5 to 7, as seen from the front. (B) is a perspective view of the clutch dial 300, as seen from the rear. (C) is a front view of the clutch dial 300. (D) is a cross-sectional view taken along line A-A in Figure 16(C). (E) is a rear view of the clutch dial 300. (F) is a right side view of the clutch dial 300. 17A is a perspective view of the front case 340 that appears in Figures 5 to 7. (B) is a front view of the front case 340. (C) is a cross-sectional view taken along line A-A in Figure 17B. (D) is a rear view of the front case 340. (E) is a right side view of the front case 340. 18A is a perspective view of the clutch hub 370 that appears in Figures 5 to 7. (B) is a front view of the clutch hub 370. (C) is a cross-sectional view taken along line A-A in Figure 18B. (D) is a rear view of the clutch hub 370. (E) is a right side view of the clutch hub 370. (A) is a perspective view of the rear ratchet 410 appearing in Figures 5 to 7, as seen from the front side. (B) is a perspective view of the rear ratchet 410, as seen from the rear side. (C) is a front view of the rear ratchet 410. (D) is a cross-sectional view taken along line A-A in Figure 19(C). (E) is a rear view of the rear ratchet 410. (F) is a right side view of the rear ratchet 410. (A) is a perspective view of the front ratchet 440 appearing in Figures 5 to 7, as seen from the front side. (B) is a perspective view of the front ratchet 440, as seen from the rear side. (C) is a front view of the front ratchet 440. (D) is a left side view of the front ratchet 440. (E) is a rear view of the front ratchet 440. (F) is a cross-sectional view taken along line A-A in Figure 20(E). 1 is a right cross-sectional view of the transmission/output component 4 separated into a transmission section 5, an output switching section 6, and an output section 7. FIG. 22(A) is a diagram of the clutch hub 370 and the rear ratchet 410 as seen from the front. (B) is a cross-sectional view taken along line A-A in Fig. 22(A) and shows the positional relationship between the locking protrusions 373 of the clutch hub 370 and the locking protrusions 412 of the rear ratchet 410 in a mode other than the vibration mode. (C) is a cross-sectional view taken along line A-A in Fig. 22(A) and shows the positional relationship between the locking protrusions 373 of the clutch hub 370 and the locking protrusions 412 of the rear ratchet 410 in the vibration mode. 1A to 1E are partially cut-away explanatory diagrams illustrating the essential configuration of the work machine 1 when it is in clutch mode and the set tightening torque is set to the minimum, as viewed from different perspectives. 1A to 1E are partially cut-away explanatory diagrams showing the essential configuration of the work machine 1 in clutch mode with the set tightening torque set to the maximum, as seen from different viewpoints. 1A to 1E are partially cut-away explanatory diagrams illustrating the essential configuration of the work machine 1 set in drill mode, as viewed from different viewpoints. 1A to 1E are partially cut-away explanatory diagrams illustrating the essential configuration of a work machine 1 set in vibration mode, viewed from different viewpoints. FIG. 4 is a perspective view of the transmission/output component 4 as seen from the rear. FIG. FIG. FIG. 4 is a rear cross-sectional view of the transmission/output component 4, taken along the engagement portion between the shift arm 71 and the slide ring gear 57. FIG. 10 is a perspective view of the upper part of the work machine 1 to which the sub-handle 600 is attached, as viewed from the front. FIG. 10 is a perspective view of the upper part of the work machine 1 to which the sub-handle 600 is attached, viewed from the rear. FIG. 2 is a front view of the work machine 1 with the sub-handle 600 attached. FIG. 2 is a front cross-sectional view of the work machine 1 equipped with the sub-handle 600. FIG. FIG. FIG. 37 is an exploded perspective view of the sub-handle 600 as seen from a different viewpoint than that of FIG. 36 . 6 is an explanatory diagram of the openable and closable range of the mount portion 601 of the sub-handle 600. FIG. 10 is a diagram showing that the sub-handle 600 can be rotated within a predetermined angle range in the stored state. FIG.

This embodiment relates to a work machine 1. The work machine 1 is a vibration driver drill. Figures 3 and 4 define the mutually perpendicular front-to-back and up-to-down directions of the work machine 1. Furthermore, the left-to-right directions, which are perpendicular to the front-to-back and up-to-down directions, are defined based on the operator facing forward.

The front-to-rear direction is a direction parallel to the axial direction of the motor shaft 31. The front side corresponds to one side of the axial direction. The rear side corresponds to the other side of the axial direction. The up-to-down direction is a direction connecting the motor accommodating section 11 and the battery pack mounting section 13 perpendicular to the front-to-rear direction.

As shown in Figures 1 to 4, the work machine 1 includes a housing 10. The housing 10 is, for example, a resin molded body with a two-part structure, left and right. The housing 10 has a motor accommodating section 11, a handle section 12, and a battery pack mounting section 13.

The motor housing 11 is a cylindrical section whose central axis is parallel to the front-to-rear direction. The work machine 1 is provided with a tail cover 15 that covers the rear opening of the motor housing 11. The work machine 1 is provided with a shift knob 21 on top of the motor housing 11. The shift knob 21 is a reduction ratio switching operation unit that rotates a shift arm 71 that appears in Figures 5 to 7 to move a slide ring gear 57 (described below) back and forth, thereby switching the reduction ratio of the transmission mechanism 50 shown in Figure 5. The shift arm 71 is made of, for example, metal, and corresponds to the reduction ratio switching unit.

The handle portion 12 extends downward from the bottom of the motor housing portion 11. The work machine 1 is provided with a trigger switch 17 at the upper end of the handle portion 12, which can switch the motor 30 between driving and stopping. The work machine 1 is provided with a forward/reverse switch 19 at the boundary between the motor housing portion 11 and the handle portion 12, which can switch the motor 30 between forward and reverse rotation.

The battery pack mounting section 13 is connected to the lower end of the handle section 12. A battery pack 25, which serves as the power source for the work machine 1, is removably mounted to the battery pack mounting section 13. As shown in Figure 4, the work machine 1 has a control board section 23 within the battery pack mounting section 13. The control board section 23 is equipped with a microcontroller that controls the drive of the motor 30, an inverter circuit for supplying current to the motor 30, and the like.

As shown in Figure 4, the work machine 1 has a motor 30, a fan 35, and a sensor board 37 within the motor housing 11. The motor 30 is, for example, an inner rotor type brushless motor, and is driven by power from the battery pack 25. The motor 30 has a motor shaft 31 which serves as the output shaft. The fan 35 is provided behind the main body of the motor 30 (the part of the motor 30 excluding the motor shaft 31), rotates integrally with the motor shaft 31, and generates cooling air to cool the motor 30 and other components. The sensor board 37 is provided in front of the main body of the motor 30. The sensor board 37 is equipped with a magnetic sensor such as a Hall IC that outputs a signal corresponding to the rotational position of the motor 30.

(Configuration of transmission/output component 4) Figures 5 to 20 relate to the configuration of the transmission/output component 4 (transmission/output unit) of the work machine 1, i.e., the configuration of the part forward of the motor 30.

The transmission/output component 4 has a motor spacer 40 as a cover for the first case.

As shown in Figures 6 and 7, the motor spacer 40 has a bearing holder portion 41, a gear portion 42, and four screw insertion holes 43.

The bearing holder 41 is located at the rear center of the motor spacer 40. As shown in Figure 4, the bearing holder 41 holds a ball bearing 33 (bearing) that supports the front part of the motor shaft 31. The gear portion 42 is provided on the inner surface of the motor spacer 40. In other words, the motor spacer 40 functions as the first stage ring gear of the transmission mechanism 50.

Each of the four screw insertion holes 43 is a through hole for passing a screw 44 through. The screws 44 are fixing parts that fix the motor spacer 40 and rear case 60 to the gear case 140. The two upper screws 44 correspond to the first fixing part, and the two lower screws 44 correspond to the second fixing part. The screws 44 extend in the front-to-rear direction. The screw collar 45 that appears in Figures 6 and 7 is made of, for example, metal, and is a member through which the two upper screws 44 pass.

The transmission/output component 4 has a rear case 60 as the cylindrical case of the first case. The rear case 60 is made of, for example, resin.

As shown in Figures 8(A) to (G), the rear case 60 has a cylindrical portion 61, two screw boss portions 62 as insertion portions, a guide protrusion portion 63, a guide hole 64, a spring retaining hole 65, a flange portion 66, and two through holes 67.

The cylindrical portion 61 is a cylindrical portion coaxial with the motor shaft 31. The screw boss portions 62 are provided at the lower left and right ends of the cylindrical portion 61 so as to protrude radially outward. The through hole 67 penetrates the screw boss portion 62 in the front-to-rear direction. The through hole 67 is the portion through which the two lower screws 44 shown in Figures 6 and 7 are passed.

The guide protrusion 63 functions as a rotation guide for the shift arm 71. The guide hole 64 is a long, through hole (groove-shaped hole) through which the shift arm 71 passes, and serves as a guide for the forward and backward movement of the lower part of the shift arm 71. The spring retaining hole 65 is a blind hole that opens to the front of the flange 66 and retains the rear end of the stopper spring 117 that appears in Figures 5 to 7. The flange 66 extends radially outward from the front end of the cylindrical portion 61.

The left grease cover 68 and right grease cover 69 shown in Figures 6 and 7 are made of, for example, resin, and are attached to the left and right sides of the cylindrical portion 61 so as to cover the left and right guide holes 64, and each function as a space to store lubricating oil leaking from the guide holes 64.

The transmission/output component 4 includes a final ring gear 90. The final ring gear 90 is made of, for example, metal.

As shown in Figures 9(A) to (G), the final ring gear 90 has six outer peripheral convex portions 91 (protrusions), a cylindrical portion 92, a flange portion 93, a gear portion 94, six front convex portions 95, and six front concave portions 96.

The cylindrical portion 92 is a cylindrical portion coaxial with the motor shaft 31. The flange portion 93 extends radially outward from the front end of the cylindrical portion 92. The six outer peripheral convex portions 91 are arranged at equal angular intervals in the circumferential direction, and each protrudes radially outward from the front of the outer peripheral surface of the cylindrical portion 92. The outer peripheral convex portions 91 are provided across the front of the outer peripheral surface of the cylindrical portion 92 and the back surface of the flange portion 93. The gear portion 94 is provided on the inner peripheral surface of the cylindrical portion 92.

The front convex portion 95 and the front concave portion 96 are provided on the front surface of the flange portion 93. The six front concave portions 96 are arranged at equal angular intervals in the circumferential direction. The front convex portion 95 is located between adjacent front concave portions 96. The rear end portion of the clutch pin 131, described below, is pressed against the front concave portion 96.

The transmission/output component 4 is provided with a stopper block 120 as a stopper portion. The stopper block 120 is made of, for example, metal.

As shown in Figures 10(A) to (H), the stopper block 120 has a base 121, a spring retaining portion 122, a locking protrusion 123, and a wide protrusion 124.

The base 121 is a planar portion (plate-shaped portion) that fits along the inner circumferential surface of the gear case 140. The spring retaining portion 122 is a recess provided on the back surface of the base 121, and retains the front end of the stopper spring 117 that appears in Figures 5 to 7. The base 121 is located between the inner circumferential surface of the gear case 140 and the outer circumferential surface of the final ring gear 90.

The locking protrusion 123 is provided on one surface of the base 121, which surface faces the outer peripheral surface of the final ring gear 90. The locking protrusion 123 is a protrusion that engages with the outer peripheral protrusion 91 of the final ring gear 90 when in the locking position described below, thereby preventing the final ring gear 90 from rotating.

The wide protrusion 124 is connected to the rear of the locking protrusion 123. It has a wider circumferential width than the locking protrusion 123. The wide protrusion 124 is provided to form the spring retaining hole 122.

The transmission/output component 4 has a gear case 140 as a second case. The gear case 140 is made of, for example, metal.

As shown in Figures 11(A) to (E), the gear case 140 has a rear cylindrical portion 141, a front wall portion 142, six through holes 143, three anti-rotation portions 144, three through holes 145, a central through hole 146, four through holes 147, anti-rotation portion protrusions 148 and 149, a front cylindrical portion 150, four screw holes 151, three stopper insertion grooves 152, and three stopper insertion holes 153.

The rear cylindrical portion 141 is a cylindrical portion coaxial with the motor shaft 31 and forms part of the outer shell of the work machine 1. The front wall portion 142 connects the front portion of the rear cylindrical portion 141 to the rear portion of the front cylindrical portion 150 and extends to the radially inner side of the front cylindrical portion 150. Six through holes 143 penetrate the front wall portion 142 in the fore-and-aft direction on the radially outer side of the front cylindrical portion 150, and each hold a pin sleeve 161 (e.g., made of metal) that appears in Figures 6 and 7.

The three anti-rotation portions 144 are arranged at equal angular intervals in the circumferential direction, and each protrudes forward from the front end of the front cylindrical portion 150, splitting into two branches. The anti-rotation portions 144 clamp the anti-rotation protrusions 285 of the ratchet cam ring 280 (described below) from both sides in the circumferential direction, preventing the ratchet cam ring 280 from rotating.

The three through holes 145 penetrate the front wall portion 142 in the front-to-rear direction, radially inside the front cylindrical portion 150. The through holes 145 are the portions through which the screws 133 shown in Figures 5 to 7 are passed, and correspond to the transmission unit housing side mounting portions. The spring washers 135 shown in Figures 6 to 7 are made of metal, for example, and are interposed between the heads of the screws 133 and the periphery of the through holes 145 to prevent the screws 133 from loosening. The central through hole 146 is the portion through which the spindle 470 is passed. The four through holes 147 are the portions through which the screws 27 shown in Figure 1 are passed, i.e., the screws 27 used to secure the gear case 140 to the motor accommodating portion 11 from the front.

The anti-rotation convex portions 148, 149 are protrusions that engage (fit) with the anti-rotation concave portions 218, 219 of the rear stopper cam ring 210 described below, preventing the rear stopper cam ring 210 from rotating. The front cylindrical portion 150 is a cylindrical portion that is coaxial with the motor shaft 31 and has a smaller diameter than the rear cylindrical portion 141. The four screw holes 151 are portions into which the screws 44 shown in Figures 6 and 7 are threaded.

The three stopper insertion grooves 152 are provided at equal angular intervals around the circumferential surface of the rear cylindrical portion 141, and are recessed grooves that extend in the front-to-rear direction. The base 121 of the stopper block 120 fits into each stopper insertion groove 152. The stopper block 120 can move in the front-to-rear direction while being guided by the stopper insertion grooves 152.

The three stopper insertion holes 153 each penetrate the front wall portion 142 in the front-to-rear direction and communicate with the stopper insertion groove 152. The stopper block 120 can protrude forward from the front wall portion 142 by penetrating each stopper insertion hole 153.

The aforementioned motor spacer 40, rear case 60, and gear case 140 are combined with each other by four screws 44 to form a transmission housing that houses the transmission mechanism 50.

Here, the transmission mechanism 50 is a reduction mechanism consisting of a planetary gear mechanism, and includes the gear portion 42 of the motor spacer 40, the first planetary gear 51, the first carrier 55, the slide ring gear 57, the second planetary gear 81, the second carrier 85, the final planetary gear 87, the final ring gear 90, and the final carrier 101. These components that make up the transmission mechanism 50 are made, for example, of metal.

The needle bearing 53 shown in Figures 6 and 7 is interposed between the inner surface of the first planetary gear 51 and a pin protruding rearward from the first carrier 55.

The slide ring gear 57 has a groove 58 that engages with the end of the shift arm 71. The slide ring gear 57 moves back and forth in response to the back and forth movement of the end of the shift arm 71 as the shift arm 71 rotates.

When the slide ring gear 57 is positioned forward, it meshes with the second planetary gear 81. At this time, the slide ring gear 57 is fixed so that it cannot rotate by a shift dog 75 (made of metal, for example), and the transmission mechanism 50 has a high reduction ratio with three speed reduction stages.

When the slide ring gear 57 is positioned rearward, it meshes with both the first planetary gear 51 and the second planetary gear 81. At this time, the transmission mechanism 50 has a low reduction ratio with two stages of reduction.

The spline hub 105 shown in Figures 5 to 7 is made of, for example, metal, and is a part that meshes with the inner periphery of the final carrier 101 and the outer periphery of the rear end of the spindle 470, transmitting the rotation of the final carrier 101 to the spindle 470. The final carrier 101 is made of, for example, metal.

The roller 103 and lock ring 110 shown in Figures 6 and 7 are made of metal, for example, and are components that suppress the transmission of rotation from the spindle 470 and chuck 500 side to the final carrier 101 side. When an attempt is made to rotate the chuck 500, the roller 103 is sandwiched and fixed between the outer periphery of the spline hub 105 and the inner periphery of the lock ring 110. The components are positioned such that the roller 103 is not fixed when rotation is transmitted from the final carrier 101 side to the spindle 470 and chuck 500 side.

The hub washer 115 shown in Figures 6 and 7 is made of, for example, metal and is a part that is interposed between the front surface of the spline hub 105 and the back surface of the front wall portion 142 of the gear case 140 to prevent contact between the gear case 140 and the spline hub 105 and reduce friction.

The transmission/output component 4 has a rear stopper cam ring 210 as the first cam.

The rear stopper cam ring 210 is located forward of the stopper block 120 and contacts the front end of the stopper block 120, and is biased forward by the stopper spring 117 via the stopper block 120, restricting rotation relative to the gear case 140.

As shown in Figures 12(A) to (G), the rear stopper cam ring 210 has a flat portion 211, an outer peripheral inclined portion 212, an outer peripheral flat portion 213, an inner peripheral inclined portion 214, an inner peripheral flat portion 215, and anti-rotation recesses 218 and 219.

The flat portion 211 is a planar portion perpendicular to the front-to-rear direction provided on the front surface of the rear stopper cam ring 210. The outer peripheral inclined portion 212 is provided on the radially outer portion of the front surface of the rear stopper cam ring 210. One end of the outer peripheral inclined portion 212 is connected to the flat portion 211, and is an inclined surface that inclines from the flat portion 211 so that it becomes more rearward as you move clockwise when viewed from the front. The outer peripheral flat portion 213 is a planar portion perpendicular to the front-to-rear direction that extends circumferentially from the other end of the outer peripheral inclined portion 212. The outer peripheral inclined portion 212 and the outer peripheral flat portion 213 form a recess or hole.

The inner circumferential inclined portion 214 is provided on the radially inner portion of the front surface of the rear stopper cam ring 210. The inner circumferential inclined portion 214 is located approximately 180° apart from the outer circumferential inclined portion 212 in the circumferential direction. The inner circumferential inclined portion 214 is connected at one end to the flat portion 211 and is an inclined surface that inclines from the flat portion 211 so that it becomes more rearward as it moves clockwise when viewed from the front. The inner circumferential flat portion 215 is a flat portion that is perpendicular to the fore-and-aft direction and extends circumferentially from the other end of the inner circumferential inclined portion 214. The inner circumferential inclined portion 214 and the inner circumferential flat portion 215 form a recess or hole.

The anti-rotation recesses 218, 219 engage (fit) with the anti-rotation protrusions 148, 149 of the gear case 140 mentioned above, preventing the rear stopper cam ring 210 from rotating relative to the gear case 140.

The transmission/output component 4 is equipped with a front stopper cam ring 230 as a second cam. The front stopper cam ring 230 is made of, for example, resin.

The front stopper cam ring 230 is located forward of the rear stopper cam ring 210 and rotates together with the clutch dial 300.

As shown in Figures 13(A) to (G), the front stopper cam ring 230 has an outer peripheral protrusion 232, an inner peripheral protrusion 234, and two locking protrusions 235.

The outer peripheral protrusion 232 protrudes rearward from the radially outer portion of the front stopper cam ring 230. The outer peripheral protrusion 232 is a flat or curved plate-shaped portion that is approximately perpendicular to the radial direction. The radial position of the outer peripheral protrusion 232 is equal to the radial positions of the outer peripheral inclined portion 212 and the outer peripheral flat portion 213 of the rear stopper cam ring 210.

The inner peripheral protrusion 234 protrudes rearward from the radially inner portion of the front stopper cam ring 230. The inner peripheral protrusion 234 is a flat or curved plate-shaped portion that is approximately perpendicular to the radial direction. The inner peripheral protrusion 234 is located approximately 180° apart from the outer peripheral protrusion 232 in the circumferential direction. The radial position of the inner peripheral protrusion 234 is equal to the radial positions of the inner peripheral inclined portion 214 and the inner peripheral flat portion 215 of the rear stopper cam ring 210.

The two locking protrusions 235 protrude forward from the radially outer portion of the front stopper cam ring 230 at positions spaced approximately 180° apart in the circumferential direction. The locking protrusions 235 are flat or curved plate-shaped portions that are approximately perpendicular to the radial direction. The locking protrusions 235 engage (fit) with the locking recesses 302 of the clutch dial 300, which will be described later. This allows the front stopper cam ring 230 to rotate together with the clutch dial 300.

The transmission/output component 4 is equipped with a nut 260 as a screw member. The nut 260 is made of, for example, resin.

As shown in Figures 14(A) to (E), the nut 260 has a threaded portion 261, six spring engagement holes 262, and three notches 263.

The threaded portion 261 is provided on the outer peripheral surface of the nut 260 and threadably engages with the threaded portion 301 of the clutch dial 300, which will be described later. The six spring engagement holes 262 are non-through holes arranged at equal angular intervals in the circumferential direction, and each holds the front end of the clutch spring 250 (e.g., made of metal) shown in Figures 5 to 7. The three notches 263 are arranged at equal angular intervals in the circumferential direction, and each receives a screw 133 shown in Figures 5 to 7.

The thrust plate 165 shown in Figures 6 and 7 is made of, for example, metal, and is biased rearward against the nut 260 by the clutch spring 250, pressing the front end of the clutch pin 131 rearward and forcing the rear end of the clutch pin 131 against the front surface of the final ring gear 90. The clutch pin 131 is made of, for example, metal, and extends in the fore-and-aft direction through the pin sleeve 161 held in the through hole 143 of the gear case 140 mentioned above.

The transmission/output component 4 is equipped with a ratchet cam ring 280 as a cam ring. The ratchet cam ring 280 is made of, for example, metal.

As shown in Figures 15(A) to (G), the ratchet cam ring 280 has an outer peripheral protrusion 282, an inner peripheral protrusion 284, three anti-rotation protrusions 285, and three small protrusions 288.

The outer peripheral protrusion 282 protrudes forward from the radially outer portion of the ratchet cam ring 280. The outer peripheral protrusion 282 is a flat or curved plate-shaped portion that is approximately perpendicular to the radial direction.

The inner circumferential protrusion 284 protrudes forward from the radially inner portion of the ratchet cam ring 280. The inner circumferential protrusion 284 is a flat or curved plate-shaped portion that is approximately perpendicular to the radial direction.

The three anti-rotation protrusions 285 are arranged at equal angular intervals circumferentially and each protrudes toward the center of the ratchet cam ring 280. The anti-rotation protrusions 285 are sandwiched in the gap between the two-pronged anti-rotation portions 144 of the gear case 140 described above. This prevents the ratchet cam ring 280 from rotating relative to the gear case 140. The back surface of the anti-rotation protrusions 285 comes into contact with the front surface of the outer protrusion 372 of the clutch hub 370 described below and is pressed forward.

The three small protrusions 288 each protrude radially inward at a position spaced a predetermined angle circumferentially from the anti-rotation protrusion 285. The small protrusions 288 come into contact with the outer surface of the screw boss portion 345 of the front case 340 (described below) when the circumferential position of the anti-rotation protrusion 285 coincides with the circumferential position of the outer protrusion 372 of the clutch hub 370, thereby serving to determine circumferential positioning.

When setting the ratchet cam ring 280 in front of the clutch hub 370, the outer protrusion 372 of the clutch hub 370 is passed through the circumferential gap between the anti-rotation protrusion 285 and the small protrusion 288. The ratchet cam ring 280 is then rotated until the small protrusion 288 contacts the outer peripheral surface of the screw boss portion 345 of the front case 340, and the back surface of the anti-rotation protrusion 285 and the front surface of the outer protrusion 372 of the clutch hub 370 are brought into contact with each other by the biasing force of the ratchet spring 360.

The transmission/output component 4 is equipped with a clutch dial 300 as a switching operation unit. The clutch dial 300 is made of, for example, resin.

As shown in Figures 16(A) to (F), the clutch dial 300 has a threaded portion 301, two locking recesses 302, an inner recess 304, an outer hole portion 305, a cylindrical portion 306, a front wall portion 307, and a leaf spring mounting portion 308.

The cylindrical portion 306 has a central axis coaxial with the motor shaft 31, a cross section perpendicular to the fore-and-aft direction that is approximately circular, and a diameter that decreases toward the front. The front wall portion 307 extends radially inward from the front end of the cylindrical portion 306.

The threaded portion 301 is provided on the inner surface of the cylindrical portion 306. The threaded portion 301 screws into the threaded portion 261 of the nut 260 described above. The clutch dial 300 is sandwiched between the gear case 140 and the front case 340 described below in the fore-and-aft direction, and its position in the fore-and-aft direction is fixed. Therefore, the nut 260 moves in the fore-and-aft direction in conjunction with the rotation of the clutch dial 300.

The two locking recesses 302 are located approximately 180° apart in the circumferential direction, and are each formed as a notch formed by partially cutting out the lower end of the threaded portion 301. The locking recesses 302 engage with the locking protrusions 235 of the front stopper cam ring 230 described above, causing the front stopper cam ring 230 to rotate together with the clutch dial 300.

The inner recess 304 is located on the radially inner portion of the back surface of the front wall portion 307. The radial position of the inner recess 304 is equal to the radial position of the inner protrusion 284 of the aforementioned ratchet cam ring 280 (or includes the radial position range of the inner protrusion 284).

The outer peripheral side hole portion 305 penetrates the radially outer portion of the front wall portion 307 in the front-to-rear direction. The radial position of the outer peripheral side hole portion 305 is equal to the radial position of the outer peripheral side protrusion portion 282 of the aforementioned ratchet cam ring 280 (or includes the radial position range of the outer peripheral side protrusion portion 282).

The leaf spring mounting portion 308 is the part where the leaf spring 331 (e.g., made of metal) that appears in Figures 6 and 7 is mounted.

The transmission/output component 4 has a front case 340 as the output component housing. The front case 340 is made of, for example, metal.

As shown in Figures 17(A) to (E), the front case 340 has a large diameter cylindrical portion 341, a small diameter cylindrical portion 342, a connection surface portion 343, three notches 344, three screw boss portions 345, three screw holes 346, three screw holes 347, a bearing retaining portion 348, two anti-rotation protrusions 349, two anti-detachment protrusions 350, and a locking recess 351.

The large diameter cylindrical portion 341 is a cylindrical portion coaxial with the motor shaft 31. The small diameter cylindrical portion 342 is a cylindrical portion coaxial with the motor shaft 31. The small diameter cylindrical portion 342 has a smaller diameter than the large diameter cylindrical portion 341 and is located rearward of the large diameter cylindrical portion 341. A ratchet spring 360, a rear ratchet 410, a front ratchet 440, a ball bearing 461, etc. are arranged within the small diameter cylindrical portion 342. The connection surface portion 343 is a wall portion perpendicular to the front-to-rear direction that connects the rear end of the large diameter cylindrical portion 341 and the front end of the small diameter cylindrical portion 342.

The three notches 344 are arranged at equal angular intervals in the circumferential direction, and each receives an outer protrusion 372 of the clutch hub 370 described below. The three screw bosses 345 are arranged at equal angular intervals in the circumferential direction, and each protrudes radially outward from the outer circumferential surface of the small diameter cylindrical portion 342. The three screw holes 347 are blind holes that open to the back surface of the screw bosses 345, and each receives a screw 133 shown in Figures 5 to 7. The screw bosses 345 and screw holes 347 correspond to the mounting portions on the output unit housing side.

The three screw holes 346 are blind holes that open to the front surface of the connection surface portion 343, and each receives a screw 489, which appears in Figures 5 to 7. The three screw holes 346 are located at the same positions in the circumferential direction as the three screw holes 347. The bearing holder 348 holds the ball bearing 335 (bearing), which appears in Figures 5 to 7. The ball bearing 335 is made of, for example, metal, and supports the rear portion of the spindle 470 so that it can rotate freely.

The two anti-rotation protrusions 349 are located approximately 180° apart in the circumferential direction and protrude radially outward from the left and right portions of the outer peripheral surface of the large-diameter cylindrical portion 341. The anti-rotation protrusions 349 engage (fit) with the first anti-rotation recess 616 or the second anti-rotation recess 617 of the sub-handle 600 described below, and are rotation restriction portions that restrict rotation of the sub-handle 600 relative to the front case 340.

The two anti-slip protrusions 350 are located approximately 180° apart in the circumferential direction, and protrude radially outward from the left and right parts of the outer peripheral surface of the large diameter cylindrical portion 341, respectively. The protruding length of the anti-slip protrusions 350 is shorter than the protruding length of the anti-rotation protrusions 349. The anti-slip protrusions 350 extend from the anti-rotation protrusions 349 on both sides in the circumferential direction. The anti-slip protrusions 350 prevent the sub-handle 600, described below, from slipping out (detaching) forward from the front case 340.

The locking recess 351 is a groove into which the leaf spring 331 fits, and there are ones that correspond to each stage of the set tightening torque for the clutch mode, ones that correspond to the drill mode, and ones that correspond to the vibration mode. When the leaf spring 331 fits into the locking recess 351, the rotational position of the clutch dial 300 is determined and the clutch dial 300 is locked in the rotational direction, preventing it from rotating unintentionally.

The transmission/output component 4 includes a clutch hub 370.

The clutch hub 370 is a regulating part that regulates the movement (rotation) of the rear ratchet 410 in vibration mode. The clutch hub 370 is made of, for example, metal.

As shown in Figures 18(A) to (E), the clutch hub 370 has an annular portion 371, three outer protrusions 372, and six locking protrusions 373.

The annular portion 371 is a ring portion coaxial with the motor shaft 31. The three outer protrusions 372 are arranged at equal angular intervals in the circumferential direction and each protrude radially outward from the outer peripheral surface of the annular portion 371. The six locking protrusions 373 are arranged at equal angular intervals in the circumferential direction and are protrusions that each protrude radially inward from the rear of the inner peripheral surface of the annular portion 371.

The transmission/output component 4 includes a rear ratchet 410 as a second vibration component. The rear ratchet 410 is made of, for example, metal.

As shown in Figures 19(A) to (F), the rear ratchet 410 is ring-shaped and has an uneven portion 411 on its front surface, and six locking protrusions 412 on the front of its outer circumferential surface. The six locking protrusions 412 are arranged at equal angular intervals in the circumferential direction, and each protrusion protrudes radially outward.

The thrust bearing 391 and bearing washer 395 shown in Figures 6 and 7 are made of, for example, metal and are interposed between the back surface of the rear ratchet 410 and the surface of the front case 340 facing it, and receive loads in the front-to-rear direction. The thrust bearing 391 and bearing washer 395 reduce friction and suppress power loss when the tool bit 20 is pressed against an opposing material.

The transmission/output component 4 includes a front ratchet 440 as a first vibration component. The front ratchet 440 is made of, for example, metal.

As shown in Figures 20(A) to (F), the front ratchet 440 is ring-shaped and has an uneven portion 441 on its back surface. The uneven portion 441 is a vibration-generating portion that outputs vibration to the spindle 470 by coming into contact with the uneven portion 411 (vibration-generating portion) of the rear ratchet 410 and rotating relative to it.

The spring 431 shown in Figures 5 to 7 is made of, for example, metal and biases the front ratchet 440 forward relative to the rear ratchet 410. As a result, when the tool bit 20 is not pressed against the mating material, the rear ratchet 410 and the front ratchet 440 are not in contact with each other, thereby suppressing the generation of vibration. The ratchet washer 435 is made of, for example, metal and prevents contact between the front ratchet 440 and the spring 431, thereby reducing friction.

The ball bearing 461 shown in Figures 5 to 7 is made of, for example, metal, and rotatably supports the front ratchet 440 and the middle portion of the spindle 470 relative to the front case 340. The front ratchet 440 rotates integrally with the spindle 470.

The transmission/output component 4 comprises a spindle 470 and a chuck 500. The spindle 470 and the chuck 500 are both made of, for example, metal. The spindle 470 is driven to rotate by the motor 30 via the transmission mechanism 50. The chuck 500 holds the tool bit 20 shown in Figure 3 and rotates integrally with the spindle 470.

The threaded portion on the rear inner surface of the chuck 500 threads into the threaded portion on the front outer surface of the spindle 470, securing the chuck 500 to the spindle 470. The chuck 500 is also secured to the spindle 470 by a left-handed thread 495 (e.g., made of metal). The spindle 470 and the chuck 500 are firmly secured to each other and form a substantially integrated tool holder.

The bearing cover 485 shown in Figures 5 to 7 is made of, for example, metal, and is fixed to the front case 340 by screws 489 that pass through their own through holes 487 and screw into the screw holes 346 in the front case 340.

The O-ring 481 shown in Figures 5 to 7 is an elastic material such as rubber, and is provided between the inner surface of the bearing cover 485 and the outer surface of the spindle 470. The O-ring 481 slides on the inner surface of the bearing cover 485, reducing the impact when the rotation is stopped (when braking). The O-ring 481 also functions to prevent oil leakage.

The retaining ring 483 appearing in Figures 5 to 7 is made of, for example, metal and is provided on the inner surface of the small diameter cylindrical portion 342 of the front case 340, functioning to prevent the ball bearing 461 from coming loose.

(Disassembly of transmission/output component 4) Figure 21 is a right-side cross-sectional view of the transmission/output component 4 separated into the transmission component 5, output switching component 6, and output component 7.

The transmission unit 5 is located in front of the motor 30 and transmits the driving force of the motor 30 to the spindle 470. The transmission unit 5 includes a transmission unit housing (motor spacer 40, rear case 60, gear case 140) and each part held or supported therein (transmission mechanism 50, etc.).

The output switching unit 6 switches the output of the output unit 7, i.e., torque and the presence or absence of vibration. The output switching unit 6 is positioned between the output unit 7 and the transmission unit 5 in the front-to-rear direction. The output switching unit 6 includes the clutch dial 300 and various parts held or supported by it (nut 260, etc.).

The output section 7 includes the front case 340 and the various parts held or supported by it, namely the spindle 470, the chuck 500, the ball bearings 335, 461, etc.

The transmission unit 5 is removably assembled to the output unit 7 from the rear side. Specifically, the gear case 140 is assembled to the front case 340 from the rear side by screws 133 that pass through the through holes 145 of the gear case 140 and are screwed into the threaded holes 347 of the front case 340.

Screw 133 is an example of a fixing part that fixes the output part 7 and the transmission part 5. The ranges of existence of screw 133 and output switching part 6 at least partially overlap. When the fixation by screw 133 is released, the transmission part 5 can be removed from the output part 7.

When the transmission unit 5 is removed from the output unit 7, that is, when the screw 133 is removed and the gear case 140 is removed from the front case 340, the output switching unit 6 can be removed rearward from the output unit 7 while the spindle 470 and chuck 500 remain fixed.

(Clutch mode, drill mode, vibration mode) The work machine 1 has clutch mode, drill mode, and vibration mode, and any of the modes can be selected by operating the clutch dial 300.

Clutch mode is a mode in which the transmission of rotation from the transmission mechanism 50 to the spindle 470 is cut off when the set tightening torque (predetermined torque) is exceeded, i.e., the clutch mechanism is active. The set tightening torque can be adjusted in multiple steps, for example, 22 steps, by operating the clutch dial 300.

Figures 23(A) to (E) show the state in which clutch mode is selected and the set tightening torque is set to the minimum. Figures 24(A) to (E) show the state in which clutch mode is selected and the set tightening torque is set to the maximum.

The clutch mechanism stops the rotation of the final ring gear 90 up to a set tightening torque, but allows the rotation of the final ring gear 90 once the tightening torque exceeds the set tightening torque. The clutch mechanism includes a nut 260, a clutch spring 250, a thrust plate 165, and a clutch pin 131.

When a load (torque) is applied to the tool bit 20 while the motor 30 is running, the loose final ring gear 90 attempts to rotate. The clutch pin 131 is positioned in the front recess 96 of the final ring gear 90 until the set tightening torque is reached. This prevents the final ring gear 90 from rotating, and torque transmission by the transmission mechanism 50 becomes effective.

On the other hand, when the torque applied to the tool bit 20 increases and exceeds the set tightening torque, that is, when a load (torque) greater than the force that causes the clutch pin 131 to push the final ring gear 90 rearward and stop the rotation of the final ring gear 90 is applied to the final ring gear 90, the final ring gear 90 rotates and the clutch pin 131 overcomes the front convex portion 95 of the final ring gear 90. This is the clutch operation, and torque transmission by the transmission mechanism 50 is interrupted by the clutch mechanism.

The load (set tightening torque) when the clutch mechanism operates is proportional to the amount of compression of the clutch spring 250. Turning the clutch dial 300 moves the nut 260 back and forth, changing the amount of compression of the clutch spring 250.

In the states shown in Figures 23(A) to (E), the nut 260 is in its most advanced position, and the amount of compression of the clutch spring 250 is minimal (the set tightening torque is the lowest). From this state, if the nut 260 is rotated clockwise as viewed from the front, the nut 260 will retract, and the amount of compression of the clutch spring 250 will increase. In the states shown in Figures 24(A) to (E), the nut 260 is in its most advanced position, and the amount of compression of the clutch spring 250 is maximum (the set tightening torque is the highest).

(Configuration for switching to drill mode) Drill mode is a mode in which the final ring gear 90 is prevented from rotating without using a clutch mechanism, and is a mode in which the maximum tightening torque can be produced by the work machine 1.

From the state shown in Figures 24(A) to (E), i.e., the state in which the clutch mode and the set tightening torque are set to the maximum, if the clutch dial 300 is further rotated clockwise as viewed from the front to the rotation position corresponding to the drill mode, the state will become as shown in Figures 25(A) to (E), i.e., the drill mode.

The switching configuration to drill mode includes a stopper block 120, a stopper spring 117 as a biasing means, a rear stopper cam ring 210, and a front stopper cam ring 230.

The stopper block 120 is movable between a locking position (forward position) and a non-locking position (rearward position), and prevents the final ring gear 90 from rotating when in the locking position. The front end of the stopper block 120 protrudes forward beyond the final ring gear 90. The stopper spring 117 is made, for example, of metal, and urges the stopper block 120 forward, i.e., toward the locking position.

The clutch dial 300 is a switching operation part that can switch the position of the stopper block 120 between an engaged position and an unengaged position. The clutch dial 300 is located forward of the final ring gear 90. The clutch dial 300 can rotate around an extension of the axis of the motor shaft 31.

The rear stopper cam ring 210 and the front stopper cam ring 230 are restricting parts that restrict the movement of the stopper block 120 from the non-engaging position to the engaging position against the force of the stopper spring 117. The restriction by the rear stopper cam ring 210 and the front stopper cam ring 230 can be switched between on and off by operating the clutch dial 300. In other words, the rear stopper cam ring 210 and the front stopper cam ring 230 form a cam mechanism that moves the stopper block 120 between the non-engaging position and the engaging position in conjunction with the rotation of the clutch dial 300.

The rear stopper cam ring 210 is located forward of the stopper block 120, and its back surface contacts the stopper block 120. The rear stopper cam ring 210 contacts the stopper block 120 on the outer side of the final ring gear 90 in the radial direction of the final ring gear 90. The rear stopper cam ring 210 is located forward of the final ring gear 90. The rear stopper cam ring 210 is urged forward by the stopper spring 117 via the stopper block 120. The rotation of the rear stopper cam ring 210 relative to the gear case 140 is restricted by the engagement (fitting) of the anti-rotation portion protrusions 148, 149 of the gear case 140 with the anti-rotation recesses 218, 219 of the rear stopper cam ring 210.

The front stopper cam ring 230 is located forward of the rear stopper cam ring 210. The engagement (fitting) between the locking protrusion 235 of the front stopper cam ring 230 and the locking recess 302 of the clutch dial 300 causes the front stopper cam ring 230 to rotate together with the clutch dial 300. When the clutch dial 300 reaches a rotation position corresponding to the drill mode, i.e., when the front stopper cam ring 230 reaches a predetermined rotation position, the rear stopper cam ring 210 moves forward. This releases the restriction on the movement of the stopper block 120 from the unlocked position to the locked position.

The rear stopper cam ring 210 has an outer peripheral inclined portion 212 and an outer peripheral flat portion 213 as recesses, and an inner peripheral inclined portion 214 and an inner peripheral flat portion 215 as recesses. The front stopper cam ring 230 has an outer peripheral protrusion 232 and an inner peripheral protrusion 234 as protrusions. As the front stopper cam ring 230 reaches a predetermined rotation position (as the clutch dial 300 reaches the rotation position for drill mode), the outer peripheral protrusion 232 and the inner peripheral protrusion 234 descend down the outer peripheral inclined portion 212 and the inner peripheral inclined portion 214, and the rear stopper cam ring 210 moves forward. It is preferable that the slope of the outer peripheral inclined portion 212 and the inner peripheral inclined portion 214 be steeper than the slope of the thread portion 301 of the clutch dial 300.

Figures 24(A)-(E) and 25(A)-(E) show that during the process of switching from clutch mode to drill mode, the outer peripheral protrusion 232 of the front stopper cam ring 230 descends over the outer peripheral inclined portion 212 of the rear stopper cam ring 210, the rear stopper cam ring 210 advances due to the bias of the stopper spring 117, and the stopper block 120 moves to the locked position (advanced position). In drill mode, the locking protrusion 123 of the stopper block 120 in the locked position engages (abuts in the rotational direction) with the outer peripheral protrusion 91 of the final ring gear 90, preventing the final ring gear 90 from rotating. Note that the locking protrusion 123 of the stopper block 120 in the unlocked position does not engage with the outer peripheral protrusion 91 of the final ring gear 90, allowing the final ring gear 90 to rotate.

When the clutch dial 300 is within the specified rotation range corresponding to the aforementioned clutch mode (a rotational position between the states of Figures 23(A) to (E) and Figures 24(A) to (E)), the outer peripheral protrusion 232 and inner peripheral protrusion 234 of the front stopper cam ring 230 abut against the flat portion 211 of the rear stopper cam ring 210, so that the rear stopper cam ring 210 does not move forward and the stopper block 120 does not move to the engaging position.

(Configuration for switching to vibration mode) The vibration mode is a mode in which forward and backward vibrations are applied to the spindle 470 in the drill mode.

From the state shown in Figures 25(A) to (E), i.e., drill mode, if the clutch dial 300 is further rotated clockwise as viewed from the front to a rotational position corresponding to vibration mode, it will enter the state shown in Figures 26(A) to (E), i.e., vibration mode.

The drill mode switching configuration includes a ratchet cam ring 280, a ratchet spring 360, a clutch hub 370, a rear ratchet 410, and a front ratchet 440.

The rear ratchet 410 and the front ratchet 440 are vibration units that output the driving force of the motor 30 as vibration to the spindle 470. The front ratchet 440 is driven (rotated) by the driving force of the motor 30. The clutch dial 300 switches the vibration on state and the vibration off state of the rear ratchet 410 and the front ratchet 440.

The ratchet cam ring 280 and clutch hub 370 are vibration switching parts that move from a vibration-off position (retracted position) to a vibration-on position (forward position) in response to operation of the clutch dial 300. The ratchet spring 360 is made of, for example, metal, and is a biasing part that biases the ratchet cam ring 280 and clutch hub 370 forward, i.e., toward the vibration-on position.

The outer peripheral protrusion 282 and inner peripheral protrusion 284 of the ratchet cam ring 280 shown in Figures 15(A) to (E) and (G), and the inner peripheral recess 304 and outer peripheral hole 305 of the clutch dial 300 shown in Figures 16(A) to (C) and (E) are guide parts that guide the ratchet cam ring 280 and clutch hub 370 to move from the vibration off position to the vibration on position when the clutch dial 300 reaches a rotational position corresponding to the vibration mode.

When the clutch dial 300 reaches a rotational position corresponding to the vibration mode, the outer peripheral protrusion 282 of the ratchet cam ring 280 faces the outer peripheral hole 305 of the clutch dial 300, and the inner peripheral protrusion 284 of the ratchet cam ring 280 faces the inner peripheral recess 304 of the clutch dial 300. The outer peripheral protrusion 282 and inner peripheral protrusion 284 of the ratchet cam ring 280 then enter the outer peripheral hole 305 and inner peripheral recess 304 of the clutch dial 300, respectively, and the ratchet cam ring 280 and clutch hub 370 move from the vibration-off position to the vibration-on position due to the bias of the ratchet spring 360.

The inclined portions 286 and 287 shown in Figure 15(G) provided at one circumferential end of the outer peripheral protrusion 282 and inner peripheral protrusion 284 of the ratchet cam ring 280 function to smoothly move the outer peripheral protrusion 282 and inner peripheral protrusion 284, respectively, in and out of the outer peripheral hole 305 and inner peripheral recess 304 of the clutch dial 300.

The clutch hub 370 does not restrict the movement of the rear ratchet 410 in the vibration-off position, but restricts the movement of the rear ratchet 410 in the vibration-on position. Vibration occurs when the front ratchet 440 is driven by the driving force of the motor 30 relative to the rear ratchet 410, whose movement is restricted.

The clutch hub 370 is biased forward by the ratchet spring 360, pressing the ratchet cam ring 280 forward. The locking protrusion 373 of the clutch hub 370, shown in Figures 18(A) to (D), and the locking protrusion 412 of the rear ratchet 410, shown in Figures 19(A) to (C) and (E) to (F), engage with each other as shown in Figures 22(C) and 26(D) when the clutch hub 370 is in the vibration-on position.

As shown in Figures 22(B) and (C), both circumferential sides of the locking protrusion 373 of the clutch hub 370 and the locking protrusion 412 of the rear ratchet 410 are provided with inclined portions 374, 413 that make it difficult for the clutch hub 370 to move from the vibration-on position to the vibration-off position. Using the angle θ shown in Figures 22(B) and (C), the inclination angle is expressed as θ/2 in the front-to-rear direction. When the clutch hub 370 is in the vibration-on position, the inclined portions 374, 413 of the locking protrusions 373, 412 come into contact with each other. When a rotational force is applied to the rear ratchet 410 in this state, the engagement of the inclined portions 374, 413 applies a forward force to the clutch hub 370, making it difficult for it to move to the vibration-off position.

25(A)-(E) and 26(A)-(E) show that during the process of switching from drill mode to vibration mode, the ratchet cam ring 280 and clutch hub 370 move forward due to the bias of the ratchet spring 360, and the front-to-rear positions of the locking protrusion 373 of the clutch hub 370 and the locking protrusion 412 of the rear ratchet 410 become aligned. During this process, the outer peripheral protrusion 232 and inner peripheral protrusion 234 of the front stopper cam ring 230 move over the outer peripheral flat portion 213 and inner peripheral flat portion 215 of the rear stopper cam ring 210, and the rotation restriction of the final ring gear 90 by the stopper block 120 is effectively maintained.

When the clutch dial 300 is within a specified rotation range corresponding to the aforementioned clutch mode and drill mode (a rotational position between the states of Figures 23(A) to (E) and Figures 25(A) to (E)), the outer peripheral protrusion 282 and inner peripheral protrusion 284 of the ratchet cam ring 280 abut against the flat portion (plane portion perpendicular to the front-to-rear direction) of the clutch dial 300, and the ratchet cam ring 280 and clutch hub 370 do not move forward (do not move to the vibration on position).

(How to pass the shift arm 71) As mentioned above, the motor spacer 40, rear case 60, and gear case 140 are fixed with four screws 44 to form the transmission unit housing. This increases the rigidity of the entire transmission unit housing and can suppress deformation when, for example, the clutch mechanism is activated.

On the other hand, in a configuration in which the shift arm 71 is extended radially from the rear case 60 through the outside of the screw 44 to the guide hole 64 of the rear case 60, the motor accommodating section 11 that covers the outside of the shift arm 71 becomes larger, resulting in an increase in the size of the product.

As shown in Figures 27 to 30, in the work machine 1, the shift arm 71 is extended radially of the rear case 60 through the inside of the screw 44 to the guide hole 64 of the rear case 60.

When the motor spacer 40, rear case 60, and gear case 140 are fixed by the two upper screws 44, there is a gap between the outer surface of the rear case 60 and the two upper screws 44, and the shift arm 71 extends into this gap.

The two upper screws 44 have their portions extending in the fore-and-aft direction on the outside of the rear case 60 inserted into a screw collar 45, which is a cylindrical portion separate from the rear case 60. That is, the two upper screws 44 each pass through the screw insertion holes 43 and screw collar 45 of the motor spacer 40 and are screwed into the threaded holes 151 of the gear case 140. The screw collar 45 is used to prevent the motor spacer 40 from bending or being damaged due to overtightening of the two upper screws 44. The shift arm 71 passes through the gap between the outer surface of the screw collar 45 and the outer surface of the rear case 60.

The two lower screws 44 pass through the screw insertion holes 43 of the motor spacer 40 and the through holes 67 of the rear case 60, respectively, and are screwed into the threaded holes 151 of the gear case 140. The screw boss portion 62 with the through holes 67 is part of the rear case 60 (integral with the rear case 60), and there is no gap between the screw boss portion 62 and the outer surface of the rear case 60, but this is not the part through which the shift arm 71 passes, so there are no problems with enlargement, etc.

(Sub-handle 600) Figures 31 to 39 relate to the sub-handle 600 in this embodiment. Figures 31 to 34 and 39 show the work machine 1 with the sub-handle 600 attached. Figures 35 to 38 show the sub-handle 600 alone. The front case 340 is the handle mounting portion of the work machine 1. Note that the sub-handle 600 is not limited to an attachment form extending leftward from the work machine 1 as in Figure 31 etc., but can also be attached in a form extending rightward from the work machine 1.

(Opening and closing structure of mount portion 601) The sub-handle 600 comprises a mount portion 601, a first shaft portion 602, and a second shaft portion 603.

The mounting portion 601 is annular with a gap 614 in part of the circumferential direction and engages with the front case 340 of the work machine 1. The mounting portion 601 has a pin layer through hole 606, a first cylindrical portion 612, a second cylindrical portion 613, and an annular portion 615.

The first cylindrical portion 612 is located above the annular portion 615 and on one side of the gap 614 (left side in Figure 35) in the longitudinal direction of the gap 614 (hereinafter referred to as the "gap length direction"), and extends in the gap length direction.

The first cylindrical portion 612 has a head holding portion 624 and a shaft insertion portion 626. The head holding portion 624 holds the head 610 of the first shaft portion 602. The head holding portion 624 is located on one side of the shaft insertion portion 626 in the gap length direction (the left side in Figure 35), and is larger and non-circular, for example hexagonal, than the shaft insertion portion 626 when viewed from the gap length direction, into which the head 610 fits. The shaft insertion portion 626 is smaller than the head 610 when viewed from the gap length direction, and the shaft 611 of the first shaft portion 602 passes.

The second cylindrical portion 613 is located above the annular portion 615 and on one side of the gap 614 in the gap length direction (the right side in Figure 35), and extends in the gap length direction. The central axes of the first cylindrical portion 612 and the second cylindrical portion 613 are parallel to the gap length direction.

The second cylindrical portion 613 has a shaft insertion portion 627 and an expanded diameter portion 628. The shaft portion 611 of the first shaft portion 602 passes through the shaft insertion portion 627. The expanded diameter portion 628 is located on the other side of the shaft insertion portion 627 in the gap length direction (the right side in Figure 35), has a larger diameter than the shaft insertion portion 627, and allows the shaft portion 611 of the first shaft portion 602 to pass through it and the end of the second shaft portion 603 to be inserted into it. The pin layer through hole 606 faces the inside of the expanded diameter portion 628. The pin layer through hole 606 opens in a direction intersecting the gap length direction.

The annular portion 615 has two first anti-rotation recesses 616 and ten second anti-rotation recesses 617 on its inner surface. The two first anti-rotation recesses 616 are spaced approximately 180° apart in the circumferential direction of the mount portion 601. The two first anti-rotation recesses 616 face each other across the center of the mount portion 601. The ten second anti-rotation recesses 617 are spaced equally apart, five at a time, between the two first anti-rotation recesses 616 in the circumferential direction of the mount portion 601. The first anti-rotation recesses 616 have a longer length in the circumferential direction of the mount portion 601 than the second anti-rotation recesses 617.

A depth gauge (not shown) can be attached to the sub-handle 600, and the knob bolt 605 is used to secure the depth gauge.

The first shaft portion 602 and the second shaft portion 603 form an adjustment mechanism that can adjust the length of the gap 614 within a predetermined range, including lengths longer than the natural length. The natural length is the length of the gap 614 when no external force that widens or narrows the gap 614 is applied to the mount portion 601.

The first shaft portion 602 extends in the gap length direction and is attached to the mount portion 601 on one side of the gap 614 in the gap length direction (the left side in Figure 35) so as not to be able to move in the gap length direction. The first shaft portion 602 passes through the gap 614 and protrudes from the mount portion 601 to the other side in the gap length direction.

The second shaft portion 603 extends in the length direction of the gap and is mounted on the mount portion 601 on the other side of the gap 614 in the length direction of the gap (the right side in Figure 35) so as not to be able to move longitudinally. The second shaft portion 603 protrudes from the mount portion 601 to the other side in the length direction.

The first shaft portion 602 and the second shaft portion 603 are engaged with each other so that they can move relative to each other in the gap length direction, and the length of the gap 614 can be adjusted by moving the second shaft portion 603 relative to the first shaft portion 602 in the gap length direction.

The first and second shaft portions 603 are threadedly engaged with each other, and by rotating the second shaft portion 603 relative to the first shaft portion 602, the second shaft portion 603 can be moved longitudinally relative to the first shaft portion 602.

The first shaft portion 602 has a head portion 610 and a shaft portion 611. The head portion 610 is located on one side of the shaft portion 611 in the gap length direction, and is larger than the shaft portion 611 and has a non-circular shape, for example, a hexagonal shape, when viewed from the gap length direction. The head portion 610 fits into the head holding portion 624 of the mount portion 601, preventing the first shaft portion 602 from rotating relative to the mount portion 601 and preventing the first shaft portion 602 from slipping out of the mount portion 601 to the other side in the gap length direction (the right side in Figure 35). In addition, a retaining ring 608 provided on the inner surface of the first cylindrical portion 612 adjacent to the head holding portion 624 prevents the first shaft portion 602 from slipping out of the mount portion 601 to one side in the gap length direction (the left side in Figure 35).

The shaft portion 611 extends from the head portion 610 to the other side in the gap length direction, passes through the shaft portion insertion portions 626, 627 of the mount portion 601, and reaches the inside of the second shaft portion 603. A male thread portion 622 is provided on the outer peripheral surface of the tip portion of the shaft portion 611.

The second shaft portion 603 has, in order from the other side in the gap length direction, a grip portion 604, a large diameter portion 618, and a small diameter portion 619.

The small diameter portion 619 is inserted into the expanded diameter portion 628 of the second cylindrical portion 613 of the mounting portion 601. Both the small diameter portion 619 and the expanded diameter portion 628 have a circular cross section. The small diameter portion 619 has a pin insertion groove 620 and an O-ring insertion groove 621. The pin insertion groove 620 and the O-ring insertion groove 621 are each grooves that run around the outer periphery of the small diameter portion 619. The pin insertion groove 620 is located on one side (the left side in Figure 35) of the O-ring insertion groove 621 in the gap length direction.

A pin 607 inserted into the pin layer through hole 606 extends into the pin insertion groove 620. The pin layer through hole 606 is at the same position as the pin insertion groove 620 in the gap length direction. The pin 607 is inserted into the pin layer through hole 606 and extends inside the pin insertion groove 620, preventing the second shaft portion 603 from moving in the gap length direction relative to the second cylindrical portion 613 of the mount portion 601.

The second shaft portion 603 is rotatable relative to the second cylindrical portion 613. An O-ring 609 fits into the O-ring fitting groove 621. The O-ring 609 generates frictional resistance against the rotation of the second shaft portion 603 relative to the second cylindrical portion 613, preventing the second shaft portion 603 from rotating easily.

The second shaft portion 603 has a nut portion 623 that forms a female thread portion. The nut portion 623 screws into the male thread portion 622 of the first shaft portion 602. The nut portion 623 may be a separate part from the large diameter portion 618 and the small diameter portion 619, or may be integrated with them. In the example of Figure 35, the nut portion 623 is a separate part from the large diameter portion 618 and the small diameter portion 619.

When the grip portion 604 is turned, the entire second shaft portion 603 rotates integrally relative to the mount portion 601 and the first shaft portion 602. In conjunction with this, the second shaft portion 603 moves in the gap length direction relative to the first shaft portion 602 due to the threaded engagement between the male thread portion 622 of the first shaft portion 602 and the nut 623 of the second shaft portion 603. At this time, the engagement between the second shaft portion 603 and the second cylindrical portion 613 of the mount portion 601 via the pin 607 moves the second cylindrical portion 613 in the gap length direction relative to the first cylindrical portion 612. This adjusts the length of the gap 614.

When the grip portion 604 is turned left from the state shown in Figures 38(B) and (E), i.e., when the gap 614 is at its natural length, the second shaft portion 603 is moved relatively to the other side in the gap length direction (the right side in Figure 38), and the length of the gap 614 can be adjusted to be longer than its natural length. Figures 38(C) and (F) show the state when the length of the gap 614 is at its maximum, i.e., when the mount portion 601 is fully open. The length of the threaded engagement between the male thread portion 622 of the first shaft portion 602 and the nut 623 of the second shaft portion 603 is set so that the upper limit of the length of the gap 614 is within a predetermined length that will not damage the mount portion 601.

By turning the grip portion 604 to the right from the state shown in Figures 38(B) and (E), i.e., when the gap 614 is at its natural length, the second shaft portion 603 and the second cylindrical portion 613 of the mount portion 601 are moved relatively to one side in the gap length direction (the left side in Figure 35), and the length of the gap 614 can be adjusted to be shorter than its natural length. Figures 38(A) and (D) show the state when the length of the gap 614 is at its smallest, i.e., the state when the mount portion 601 is fully closed. By adjusting the length of the gap 614 to be shorter than its natural length, the mount portion 601 can be tightened to the front case 340, and the sub-handle 600 can be fixed to the front case 340.

By opening the gap 614 wider than its natural length, the front case 340 of the work machine 1 can be passed inside the mounting portion 601. The anti-slip protrusion 350 of the front case 340 is large enough that it cannot be inserted inside the mounting portion 601 when the gap 614 is at its natural length. The anti-slip protrusion 350 inhibits (prevents) the mounting portion 601 from slipping forward out of the front case 340 when the gap 614 is at or below its natural length.

(Structure for easy storage of sub-handle 600) To attach the sub-handle 600 to the front case 340, adjust the length of the gap 614 to be longer than its natural length, and then fit the mount portion 601 into the front case 340 from the front. Then, turn the grip portion 604 to the right to narrow the gap 614.

When attaching the sub-handle 600 to the front case 340, the attachment angle can be selected from multiple stages. Of the two first anti-rotation recesses 616 and ten second anti-rotation recesses 617 on the mounting portion 601, two that correspond to the attachment angle of the sub-handle 600 relative to the front case 340 engage with the two anti-rotation protrusions 349 on the front case 340.

The circumferential length of the first anti-rotation recess 616 of the mount portion 601 is longer than the circumferential length of the anti-rotation protrusion 349 of the front case 340. The circumferential length of the second anti-rotation recess 617 of the mount portion 601 is approximately equal to the circumferential length of the anti-rotation protrusion 349 of the front case 340.

When the second anti-rotation recess 617 of the mount portion 601 and the anti-rotation protrusion 349 of the front case 340 engage with each other, the circumferential lengths of both are approximately equal, so the sub-handle 600 can be attached to the front case 340 without or with minimal rattling. The second anti-rotation recess 617 of the mount portion 601 is used when the sub-handle 600 is not stored, i.e., when the work machine 1 is in use.

When the first anti-rotation recess 616 of the mounting portion 601 and the anti-rotation protrusion 349 of the front case 340 engage with each other, the circumferential length of the first anti-rotation recess 616 is longer than the circumferential length of the anti-rotation protrusion 349, allowing the sub-handle 600 to rotate within a predetermined angle range relative to the front case 340. The first anti-rotation recess 616 is used when the sub-handle 600 is stored, i.e., when the work machine 1 is not in use.

Figures 39(A) to (C) show that the sub-handle 600 can be rotated within a specified angle range when in the stored state.

Figure 39(A) shows the state in which the sub-handle 600 has been rotated to its maximum extent counterclockwise in the figure. This state, as shown enlarged in Figure 39(B), is the first engagement state in which the circumferential ends of the first anti-rotation recess 616 of the mount portion 601 and the anti-rotation protrusion 349 of the front case 340 engage with each other.

Figure 39 (B) shows the state in which the sub-handle 600 is in the center of its rotational range. This state is the second engagement state in which the circumferential ends of the first anti-rotation recess 616 of the mount portion 601 and the anti-rotation protrusion 349 of the front case 340 do not come into contact with each other. Note that in the second engagement state, the circumferential ends of the first anti-rotation recess 616 of the mount portion 601 and the anti-rotation protrusion 349 of the front case 340 may also engage with each other.

Even when the first anti-rotation recess 616 of the mount portion 601 and the anti-rotation protrusion 349 of the front case 340 are engaged with each other, by setting the gap 614 of the mount portion 601 to a predetermined length that is shorter than the natural length, the frictional force caused by the mount portion 601 tightening against the front case 340 prevents the sub-handle 600 from rotating relative to the front case 340.

This embodiment has the following effects.

(1) The work machine 1 includes an output switching unit 6 that switches the output (torque and presence or absence of vibration) of the output unit 7, and is positioned between the output unit 7 and the transmission unit 5. When the transmission unit 5 is removed from the output unit 7, the output switching unit 6 can be removed rearward from the output unit 7. Specifically, when the screw 133 is removed and the gear case 140 is removed from the front case 340 (removing the transmission unit 5 from the output unit 7), the output switching unit 6 can be removed rearward from the output unit 7. Therefore, even if the spindle 470 and chuck 500 cannot be released from their fixed positions, the components of the output switching unit 6, i.e., the clutch dial 300, nut 260, clutch spring 250, etc., can be replaced, improving repairability.

For comparison, consider a configuration (hereinafter referred to as "Comparative Configuration 1") in which the gear case 140 is extended forward, ball bearings 335 and 461 are held in place, and a retaining ring prevents the clutch dial 300 from slipping forward relative to the gear case 140. In Comparative Configuration 1, the retaining ring cannot be accessed unless the chuck 500 is removed from the spindle 470, and the clutch dial 300, etc. cannot be removed forward or backward. Therefore, in Comparative Configuration 1, if the clutch dial 300, etc. is damaged and needs to be replaced, it is necessary to remove the chuck 500 from the spindle 470 using a special jig or replace the entire transmission/output component 4, which increases the time and cost required for repairs. This embodiment provides an excellent solution to such problems.

(2) The transmission unit 5 and output unit 7 can be used as modules in common with multiple models, making them highly convenient.

(3) The work machine 1 is equipped with a transmission mechanism 50 including the final ring gear 90, a stopper block 120 that disables the rotation of the final ring gear 90 when it is in the locked position, and a stopper spring 117 that biases the stopper block 120 toward the locked position. Therefore, even if the front end of the convex portion 123 of the stopper block 120 attempting to move to the locked position comes into contact with the rear end of the outer peripheral convex portion 91 of the final ring gear 90, preventing it from reaching the locked position, if the final ring gear 90 subsequently rotates, the outer peripheral convex portion 91 will move from in front of the convex portion 123, and the stopper block 120 will automatically move to the locked position. This makes it possible to prevent a malfunction that would prevent the final ring gear 90 from being disabled from rotating, i.e., a malfunction that would prevent the machine from switching to drill mode.

(4) The work machine 1 can switch the position of the stopper block 120 between the locked position and the unlocked position using the clutch dial 300. Specifically, when the clutch dial 300 is rotated to the drill mode rotation position, the stopper block 120 moves to the locked position. Here, the force that moves the stopper block 120 to the locked position is the biasing force of the stopper spring 117, and is not due to threaded engagement that utilizes the rotation of the clutch dial 300. Therefore, compared to a configuration in which the stopper pin is pushed toward the final ring gear 90 by the nut 260, which moves back and forth in conjunction with the rotation of the clutch dial 300, this configuration can reduce the problem of not being able to rotate the clutch dial 300 to the drill mode rotation position, and is easier to use.

(5) The stopper spring 117 is configured to bias the stopper block 120 forward, and the stopper spring 117 and the stopper block 120 are provided behind the clutch dial 300. Therefore, compared to when the stopper spring 117 and the stopper block 120 are provided inside the clutch dial 300, the diameter of the clutch dial 300 can be prevented from increasing, and deterioration in operability when rotating the clutch dial 300 can be prevented.

(6) When the clutch dial 300 is within the clutch mode rotation range, the rear stopper cam ring 210 and the front stopper cam ring 230 function as a restricting portion that restricts movement of the stopper block 120 from the unlocked position to the locked position against the biasing force of the stopper spring 117. Furthermore, the rear stopper cam ring 210 and the front stopper cam ring 230 form a cam mechanism that moves the stopper block 120 between the unlocked position and the locked position in conjunction with the rotation of the clutch dial 300 between the drill mode rotation position and the clutch mode rotation position. Therefore, the forward and backward movement of the stopper block 120 is limited to when the clutch dial 300 rotates between the drill mode rotation position and the clutch mode rotation position, and the forward and backward movement of the stopper block 120 (movement between the unlocked position and the locked position) can be preferably achieved without relying on the threaded engagement between the clutch dial 300 and the nut 260.

(7) When the clutch dial 300 rotates between the drill mode rotation position and the clutch mode rotation position, the outer circumferential projection 232 and inner circumferential projection 234 of the front stopper cam ring 230 move along the outer circumferential inclined portion 212 and inner circumferential inclined portion 214 of the rear stopper cam ring 210. By making the inclination angles of the outer circumferential inclined portion 212 and inner circumferential inclined portion 214 steeper than the inclination of the threaded portion 301 of the clutch dial 300, the stopper block 120 can be moved significantly forward and backward in conjunction with the rotation of the clutch dial 300, compared to when the stopper block 120 is moved by the threaded engagement between the clutch dial 300 and the nut 260. This reduces the amount of clutch dial 300 operation required to switch between clutch mode and drill mode, improving usability. Furthermore, because the outer circumferential inclined portion 212 and the inner circumferential inclined portion 214 form a recess, the outer circumferential protrusion 232 and the inner circumferential protrusion 234 of the front stopper cam ring 230 can easily move in and out of the recess. This reduces sticking when switching between the clutch mode and the drill mode, improving usability.

(8) The rear stopper cam ring 210 is positioned forward of the final ring gear 90, and the stopper block 120 protrudes forward of the final ring gear 90 and engages with the rear stopper cam ring 210. As a result, the drill mode switching configuration (stopper block 120, stopper spring 117, rear stopper cam ring 210, front stopper cam ring 230) is distributed in front of and behind the final ring gear 90. Therefore, unlike when the drill mode switching configuration is biased toward either the front or rear of the final ring gear 90, it is easier to balance the radial sizes of the gear case 140 and the clutch dial 300, and layout efficiency is improved.

(9) When the clutch hub 370 of the work machine 1 reaches the vibration-on position, the clutch hub 370 restricts the movement of the rear ratchet 410. Vibration occurs when the front ratchet 440 is driven by the driving force of the motor 30 relative to the restricted movement of the rear ratchet 410. When the clutch dial 300 reaches a rotational position corresponding to the vibration mode, the outer peripheral protrusion 282 and inner peripheral protrusion 284 of the ratchet cam ring 280 move along their respective inclined portions 286 and 287 into the outer peripheral hole 305 and inner peripheral recess 304 of the clutch dial 300, and the ratchet cam ring 280 and clutch hub 370 move from the vibration-off position to the vibration-on position due to the bias of the ratchet spring 360. Therefore, compared to a configuration in which the clutch hub 370 is pushed forward by the nut 260 which moves back and forth in conjunction with the rotation of the clutch dial 300, the amount of operation of the clutch dial 300 required to switch between vibration on and off can be reduced, making it easier to use.

(10) Since the outer peripheral protrusion 282 and inner peripheral protrusion 284 of the ratchet cam ring 280 have inclined portions 286, 287, the outer peripheral protrusion 282 and inner peripheral protrusion 284 can smoothly enter and exit the outer peripheral hole 305 and inner peripheral recess 304 of the clutch dial 300, thereby reducing snagging when switching between drill mode and vibration mode, and improving usability.

(11) When the clutch dial 300 is within the rotation range of the clutch mode and drill mode, the ratchet cam ring 280 and the clutch dial 300 function as a restricting portion that restricts movement of the clutch hub 370 from the vibration-off position to the vibration-on position against the biasing force of the ratchet spring 360. Furthermore, the ratchet cam ring 280 and the clutch dial 300 form a cam mechanism that moves the clutch hub 370 between the vibration-off position and the vibration-on position in conjunction with the rotation of the clutch dial 300 between the vibration mode rotation position and the drill mode rotation position. Therefore, the forward and backward movement of the clutch hub 370 is limited to when the clutch dial 300 rotates between the vibration mode rotation position and the drill mode rotation position, and the forward and backward movement of the clutch hub 370 (movement between the vibration-off position and the vibration-on position) can be preferably achieved without relying on the threaded engagement between the clutch dial 300 and the nut 260.

(12) As shown in Figures 22(B) and (C), both circumferential sides of the locking protrusion 373 of the clutch hub 370 and the locking protrusion 412 of the rear ratchet 410 are provided with inclined portions 374, 413 that make it difficult for the clutch hub 370 to move from the vibration-on position to the vibration-off position. When a rotational force is applied to the rear ratchet 410 in the vibration-on position, the engagement between the inclined portions 374, 413 applies a forward force to the clutch hub 370, making it difficult for it to move to the vibration-off position. This prevents the clutch hub 370 from accidentally moving to the vibration-off position due to vibrations, etc.

(13) The motor spacer 40, rear case 60, and gear case 140 are fixed with four screws 44 to form a highly rigid transmission housing, which reduces deformation when the clutch mechanism is activated. Meanwhile, a gap exists between the outer surface of the rear case 60 and the two upper screws 44, and the shift arm 71 extends through this gap to the guide hole 64 in the rear case 60. Therefore, compared to a configuration in which the shift arm 71 extends radially from the rear case 60 through the outside of the screws 44 to the guide hole 64 in the rear case 60, the motor accommodating section 11, which covers the outer side of the shift arm 71, does not need to be enlarged, and the product size can be reduced.

(14) The two upper screws 44 have their portions extending in the front-to-rear direction on the outside of the rear case 60 inserted into a screw collar 45, which is a cylindrical portion separate from the rear case 60. This prevents the motor spacer 40 from bending or being damaged due to overtightening of the two upper screws 44.

(15) The front case 340 has a protrusion 350 for preventing the sub-handle 600 from slipping out, which prevents the sub-handle 600 from slipping out forward due to vibrations during work, etc., improving workability.

(16) The sub-handle 600 is annular with a gap 614 in part of its circumferential direction and includes a mount portion 601 that engages with the front case 340 of the work machine 1, and is configured so that the length of the gap 614 can be adjusted within a predetermined range, including lengths longer than the natural length. Therefore, even if the length of the gap 614 in the front case 340 is in its natural length and interferes with, for example, the anti-slip protrusion 350 of the front case 340, making attachment and detachment difficult, attachment and detachment can be easily achieved by adjusting the length of the gap 614 to be longer than the natural length.

(17) The first shaft portion 602 and the second shaft portion 603 are threadedly engaged with each other, and the length of the gap 614 can be adjusted by turning the grip portion 604 provided on the second shaft portion 603. Therefore, the length of the gap 614 can be easily adjusted, making it easy to use.

(18) The pin 607 extending into the pin insertion groove 620 of the second shaft portion 603 prevents the second shaft portion 603 from moving in the gap length direction relative to the second cylindrical portion 613 of the mount portion 601. Because the pin 607 allows the second shaft portion 603 to rotate, it does not prevent the length of the gap 614 from being adjusted by turning the second shaft portion 603.

(19) The O-ring 609 generates frictional resistance against the rotation of the second shaft portion 603 relative to the second cylindrical portion 613, thereby preventing the second shaft portion 603 from rotating easily, improving workability.

(20) The length of the threaded engagement between the male thread portion 622 of the first shaft portion 602 and the nut 623 of the second shaft portion 603 is set so that the upper limit of the length of the gap 614 is within a predetermined length that will not damage the mount portion 601. Therefore, regardless of the degree of operation by the user, damage to the mount portion 601 due to excessive widening of the gap 614 can be suppressed, resulting in improved usability.

(21) The mount portion 601 has a first anti-rotation recess 616 that is long in the circumferential direction and a second anti-rotation recess 617 that is short in the circumferential direction. When the second anti-rotation recess 617 and the anti-rotation protrusion 349 of the front case 340 are engaged with each other, their circumferential lengths are approximately equal, allowing the sub-handle 600 to be attached to the front case 340 without or with minimal rattle, enabling stable work. On the other hand, when the first anti-rotation recess 616 of the mount portion 601 and the anti-rotation protrusion 349 of the front case 340 are engaged with each other, the circumferential length of the first anti-rotation recess 616 is longer than the circumferential length of the anti-rotation protrusion 349. This allows the sub-handle 600 to be rotated within a predetermined angle range relative to the work machine 1 in the stored state, as shown in Figures 39(A) and (C), i.e., fine adjustment of the attached state is possible. This improves the ease of storing the sub-handle 600 in the work machine 1. If the angle when stored cannot be changed from the angle shown in Figure 39 (C), the flange portion 625 of the grip portion 604 will interfere with the battery pack 25, battery pack attachment portion 13, etc., making it difficult to store, but this embodiment can suitably solve such problems.

(22) Even when the first anti-rotation recess 616 of the mount portion 601 and the anti-rotation protrusion 349 of the front case 340 are engaged with each other, by setting the gap 614 of the mount portion 601 to a predetermined length that is shorter than the natural length, the frictional force generated when the mount portion 601 tightens against the front case 340 can prevent the sub-handle 600 from rotating relative to the front case 340. This makes it possible to suppress rattle of the sub-handle 600 in the stored state as needed. Furthermore, even when the first anti-rotation recess 616 of the mount portion 601 is configured to be used when the work machine 1 is in use, rattle during operation can be suppressed.

The present invention has been described above using embodiments as examples, but the present invention is not limited to these embodiments. Various modifications are possible to each of the details specifically described in the embodiments within the scope of the claims.

The concave-convex structure exemplified in the embodiment may have the concave-convex relationship reversed as appropriate. For example, the rear stopper cam ring 210 may have a convex portion, and the front stopper cam ring 230 may have a concave portion that engages with the convex portion. Similarly, the ratchet cam ring 280 may have a concave portion, and the clutch dial 300 may have a convex portion that engages with the concave portion.

The number of outer peripheral protrusions 91 and stopper blocks 120 of the final ring gear 90, the number of screws 44, 133, the number of set tightening torque levels, the number of possible angles at which the sub-handle 600 can be attached to the work machine 1, the number of first anti-rotation recesses 616 and second anti-rotation recesses 617, etc., which are exemplified as specific numbers in the embodiments, do not in any way limit the scope of the invention and can be changed as desired to suit the required specifications.

1...Work machine, 4...Transmission/output component, 5...Transmission section, 6...Output switching section, 7...Output section, 10...Housing, 11...Motor accommodating section, 12...Handle section, 13...Battery pack mounting section, 15...Tail cover, 17...Trigger switch, 19...Forward/reverse switch, 20...Tool tip, 21...Shift knob, 23...Control board section, 25...Battery pack, 27...Screw, 30...Motor, 31...Motor shaft, 33...Ball bearing, 35...Fan, 37...Sensor board, 40...Motor spacer, 41...Bearing holder, 42...Gear section, 43...Screw insertion hole, 45...Screw the same collar, 50...transmission mechanism (reduction mechanism), 51...first planetary gear, 53...needle bearing, 55...first carrier, 57...slide ring gear, 58...groove portion, 60...rear case, 61...cylindrical portion, 62...screw boss portion, 63...guide convex portion, 64...guide hole, 65...spring retaining hole, 66...flange portion, 67...through hole, 68...left grease cover, 69...right grease cover, 71...shift arm, 75...shift dog, 81...second planetary gear, 85...second carrier, 87...final planetary gear, 90...final ring gear, 91...outer peripheral convex portion , 92...Cylindrical portion, 93...Flange portion, 94...Gear portion, 95...Front convex portion, 96...Front concave portion, 101...Final carrier, 103...Roller, 105...Spline hub, 110...Lock ring, 115...Hub washer, 117...Stopper spring (biasing means), 120...Stopper block, 121...Base, 122...Spring holding portion, 123...Latching convex portion (protrusion portion), 124...Wide convex portion, 131...Clutch pin, 133...Screw, 135...Spring washer, 140...Gear case, 141...Rear cylindrical portion, 142...Front wall portion, 14 3...through hole, 144...rotation prevention portion, 145...through hole, 146...central through hole, 147...through hole, 148...rotation prevention portion protrusion, 149...rotation prevention portion protrusion, 150...front cylindrical portion, 151...screw hole, 152...stopper insertion groove, stopper insertion hole, 161...pin sleeve, 165...thrust plate, 210...rear stopper cam ring, 211...flat portion, 212...outer peripheral side inclined portion, 213...outer peripheral side flat portion, 214...inner peripheral side inclined portion, 215...inner peripheral side flat portion, 218...rotation prevention recess, 219...rotation prevention recess, 230...front stopper cam ring, 2 32...Outer peripheral projection, 234...Inner peripheral projection, 235...Latching projection, 250...Clutch spring, 260...Nut, 261...Threaded portion, 262...Spring locking hole, 263...Notch, 280...Ratchet cam ring, 282...Outer peripheral projection, 284...Inner peripheral projection, 285...Detent convex portion, 286...Inclined portion, 287...Inclined portion, 288...Small projection, 300...Clutch dial, 301...Threaded portion, 302...Latching recess, 304...Inner peripheral recess, 305...Outer peripheral hole, 306...Cylindrical portion, 307...Front wall portion, 308...Leaf spring mounting portion, 331...leaf spring, 335...ball bearing (bearing), 340...front case, 341...large diameter cylindrical portion, 342...small diameter cylindrical portion, 343...connection surface portion, 344...notch portion, 345...screw boss portion, 346...screw hole, 347...screw hole, 348...bearing holding portion, 349...rotation prevention protrusion portion (rotation regulating portion), 350...removal prevention protrusion portion, 351...locking recess portion, 360...ratchet spring, 370...clutch hub, 371...annular portion, 372...outer protrusion portion, 373...locking protrusion portion, 374...inclined portion, 391...thrust bearing, 395...bear Ring washer, 410... rear ratchet, 411... uneven portion (vibration generating shape portion), 412... locking convex portion, 413... inclined portion, 431... spring, 435... ratchet washer, 440... front ratchet, 441... uneven portion (vibration generating shape portion), 461... ball bearing, 470... spindle, 481... O-ring, 483... retaining ring, 485... bearing cover, 487... through hole, 489... screw, 495... left-handed screw, 500... chuck, 600... sub-handle, 601... mount portion, 602... first shaft portion, 603... second shaft Shaft portion, 604...grip portion, 605...knob bolt, 606...pin layer through hole, 607...pin, 608...retaining ring, 609...O-ring, 610...head, 611...shaft portion, 612...first cylindrical portion, 613...second cylindrical portion, 614...gap, 615...annular portion, 616...first anti-rotation recess, 617...second anti-rotation recess, 618...large diameter portion, 619...small diameter portion, 620...pin insertion groove, 621...O-ring fitting groove, 622...male thread portion, 623...nut portion, 624...head holding portion, 625...flange portion, 626...shaft insertion portion, 627...shaft insertion portion, 628...expanded diameter portion.

Claims (6)

A motor;
a tool holder located on one side of the motor in an axial direction of the motor;
a transmission unit including a transmission mechanism including a gear that transmits rotation of the motor to the tool bit holder, and a transmission unit housing that accommodates the transmission mechanism;
a reduction ratio switching unit that switches the reduction ratio of the transmission mechanism,
The transmission housing includes:
a first case including a cylindrical case having an opening on the other side in the axial direction, and a cover that holds a motor bearing portion that supports a shaft of the motor and closes the opening of the cylindrical case ;
a second case located on one side of the first case in the axial direction,
a first fixing portion extending in the axial direction and fixing the cover of the first case and the second case from the other side in the axial direction ;
a gap is formed between an outer surface of the cylindrical case of the first case and the first fixing portion when the lid of the first case and the second case are fixed by the first fixing portion;
a portion of the reduction ratio switching portion extending into the gap;
A work machine characterized by: a second fixing portion extending in the axial direction at a position different from the first fixing portion and fixing the first and second cases together;
an insertion portion through which the second fixing portion is inserted is provided on the opposite side of the first case from the reduction ratio switching portion;
2. The work machine according to claim 1. The insertion portion is integral with the first case.
3. The work machine according to claim 2. a cylindrical portion into which the first fixing portion is inserted, the cylindrical portion being separate from the first case;
The gap exists between the outer surface of the cylindrical portion and the outer surface of the first case.
2. The work machine according to claim 1. the first and second fixing portions are screws,
the insertion portion is a through hole through which the screw passes,
the second case has a screw hole into which the screw is screwed;
3. The work machine according to claim 2. The tool bit holder is
a spindle connected to the transmission mechanism;
a chuck that is screwed onto the spindle and holds the tool bit,
a clutch mechanism that interrupts the transmission of rotation from the transmission mechanism to the spindle at a predetermined torque;
a switching operation unit capable of switching the predetermined torque, the switching operation unit being provided on one side of the second case in the axial direction,
2. The work machine according to claim 1.