Reciprocating cutting tool

Abstract

To provide a reciprocative cutting tool configured to prevent entry of chips into a space between an operation drum and a housing from worsening motion of the operation drum.SOLUTION: A reciprocating saw as a reciprocative cutting tool comprises: a motor 3; a rod-like slider 6 that is reciprocated in a longitudinal direction by a reciprocating conversion mechanism 5; a power transmitting housing 20 that stores the reciprocating conversion mechanism 5; a blade holding part 102 to / from which a blade can be attached and detached, and which is allowed to perform an operation relating to detachment of the blade and is arranged at a front end part of the slider 6; and a release drum 140 as an operation drum which rotates to operate the operation of the detachment of the blade holding part 102. The release drum 140 is rotatably held on the power transmitting housing 20 through two ring springs 144A and 144B.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a reciprocating cutting tool such as a rechargeable reciprocating saw. [Background technology]

[0002] US Pat. No. 8,230,607 (Patent Document 1) discloses a reciprocating tool 10 having a sleeve 138 (operating drum) rotatably mounted within a housing 14 for removing a blade. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 8,230,607 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a reciprocating cutting tool that suppresses deterioration of the movement of an operation drum due to intrusion of cutting chips between the operation drum and a housing. [Means for solving the problem]

[0005] In order to achieve the above object, the reciprocating cutting tool of the present disclosure may include a motor, a rod-shaped slider, a reciprocating motion conversion mechanism in which the extension direction of the slider is a front-rear direction and the rotation of the motor is converted into a reciprocating motion in the front-rear direction and transmitted to the slider, and a power transmission housing that accommodates the reciprocating motion conversion mechanism. The reciprocating cutting tool may include a tool holder that is detachable from a tool tip and that is capable of performing operations related to the attachment and detachment of the tool tip and that is disposed at a front end of the slider. The reciprocating cutting tool may include an operation drum that operates the operation of the tool tip holder by its own rotation. The operation drum may be rotatably held in the power transmission housing via one or more ring members. Effect of the Invention

[0006] According to the reciprocating cutting tool of the present disclosure, deterioration of the movement of the operation drum is suppressed. [Brief description of the drawings]

[0007] [Figure 1] This is an oblique view of the reciprocating saw from the upper right front. [Diagram 2] This is an oblique view of the reciprocating saw from the upper left front. [Diagram 3] FIG. 2 is a central longitudinal sectional view of the front part of FIG. [Figure 4] FIG. 4 is a central longitudinal sectional view of the front part of FIG. 3. [Diagram 5] FIG. 4 is a cross-sectional view taken along line AA in FIG. [Figure 6] FIG. 4 is a cross-sectional view taken along line BB in FIG. [Figure 7] 2 is an exploded perspective view of the slider and release mechanism in the reciprocating saw of FIG. 1, viewed from the upper left rear. FIG. [Figure 8] 2 is an exploded perspective view of the slider and release mechanism in the reciprocating saw of FIG. 1, viewed from the upper right front. FIG. [Figure 9] 9A is a central vertical cross-sectional view of the blade holding portion (blade standby state) of the slider in FIG. 6, and FIG. 9B is a horizontal cross-sectional view of the holding pin portion of the blade holding portion (blade standby state). [Figure 10] 10A is a central vertical cross-sectional view of the blade holding portion (blade attached state) of the slider in FIG. 6, and FIG. 10B is a horizontal cross-sectional view of the holding pin portion of the blade holding portion (blade attached state). [Figure 11] 11A is a central vertical cross-sectional view of the blade holding portion of the slider in FIG. 6 (with the blade removed), and FIG. 11B is a horizontal cross-sectional view of the holding pin portion of the blade holding portion (with the blade removed). [Figure 12] 12A is a central vertical cross-sectional view of the blade holding portion (with the holding pin bottomed out) of the slider in FIG. 6, and FIG. 12B is a horizontal cross-sectional view of the holding pin portion of the blade holding portion (with the holding pin bottomed out). [Figure 13] 2 is an exploded perspective view of the front part of an upper power transmission housing, a release mechanism, and a front part of a lower power transmission housing of the reciprocating saw of FIG. 1, as viewed from above. FIG. [Figure 14] 2 is an exploded perspective view of the front part of an upper power transmission housing, a release mechanism, and a front part of a lower power transmission housing of the reciprocating saw of FIG. 1, as viewed from below. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] In an embodiment of the present disclosure, the operation of the tool holder may be a removal operation for removing the tool. With this configuration, deterioration of operability of the operation drum related to the removal operation is suppressed. In one embodiment of the present disclosure, the tool holder has a protrusion, and the operation of the tool holder is performed by rotational movement of the protrusion about an axis in the front-rear direction, and the operation drum has an inner protrusion that protrudes inward and rotates about an axis in the front-rear direction to operate the rotational movement of the protrusion. With this configuration, deterioration of the operability of the operation drum, which operates the operation of the tool holder by rotational movement, is suppressed. In one embodiment of the present disclosure, the ring member may be a ring spring. Also, in one embodiment of the present disclosure, a circular groove may be formed on the outer surface of the operation drum, and a radially inner portion of the ring member may be inserted into the groove. According to these configurations, the ring member for maintaining the operability of the operation drum can be more easily provided.

[0009] In one embodiment of the present disclosure, the operation drum may have a flange portion. Also, the power transmission housing may have a first groove portion into which the flange portion fits and a cylindrical belt portion with which the ring member comes into contact. With this configuration, the operation drum is prevented from coming off, and deterioration of the operability of the operation drum is suppressed. In one embodiment of the present disclosure, the first groove portion and the cylindrical band portion may be adjacent to each other. With this configuration, the operation drum and the surrounding parts that are prevented from being dislodged and that are prevented from deteriorating in operability are provided in a compact manner.

[0010] In one embodiment of the present disclosure, the reciprocating cutting tool may include an elastic body that biases the operation drum to the initial rotation position. The elastic body may be disposed outside the operation drum. The power transmission housing may have a second groove portion into which the elastic body is inserted and a cylindrical belt portion with which the ring member contacts. With this configuration, deterioration of the operability of the operation drum that can be returned to the initial rotation position is suppressed. In one embodiment of the present disclosure, the second groove portion and the cylindrical band portion may be adjacent to each other. With this configuration, the operation drum and the surrounding parts are compactly provided, which suppresses deterioration of operability and enables return to the initial rotation position.

[0011] In one embodiment of the present disclosure, two ring members may be provided. Also, the ring members may be disposed at the front and rear of the operation drum. According to these configurations, deterioration of the operability of the operation drum is further suppressed. In one embodiment of the present disclosure, the width of the ring member may be 4 mm or less. With this configuration, the contact area of ​​the ring member with the power transmission housing is reduced, and deterioration of the operability of the operation drum is further suppressed. In one embodiment of the present disclosure, the tool bit may have an action part that acts on the workpiece, and may be attached to the tool bit holder with the action part on at least one of the upper and lower sides. With this configuration, deterioration of the operability of the operation drum for the reciprocating cutting tool, which is easier to handle, is suppressed.

[0012] In one embodiment of the present disclosure, the ring member may be made of metal, iron or an iron alloy. The operation drum may be made of synthetic resin. The power transmission housing may be made of metal, aluminum or an aluminum alloy. These configurations make the ring member and the power transmission housing more durable. The operation drum is easier to form, and the resistance of the operation drum to external electric shocks is improved. Furthermore, when the operation drum and the power transmission housing are made of different materials, the ring member is made of a material closer to the power transmission housing than the operation drum, which suppresses deterioration of the operability of the operation drum and extends the life of the operation drum, ring member and power transmission housing. EXAMPLES

[0013] Hereinafter, embodiments of the present disclosure (including modified examples) will be described with reference to the accompanying drawings. The present embodiment relates to a power tool, a reciprocating cutting tool as an example of a reciprocating tool, and more specifically, to a reciprocating saw. In this embodiment, the front, back, up, down, left and right directions are defined for the convenience of explanation, and may change depending on at least one of the work situation and the state of the moving parts.

[0014] Fig. 1 is a perspective view of the reciprocating saw 1 as seen from the upper right front. Fig. 2 is a perspective view of the reciprocating saw 1 as seen from the upper left front. Fig. 3 is a central vertical cross-sectional view of the front part of Fig. 1. Fig. 4 is a central vertical cross-sectional view of the front part of Fig. 3. In FIG. 3, the right side of the drawing is the front of the reciprocating saw 1, and the top of the drawing is the top of the reciprocating saw 1.

[0015] The reciprocating saw 1 has a main body housing 2, a motor 3, a fan 4, a reciprocating motion conversion mechanism 5, a slider 6 as an output section, a release mechanism 7, a counterweight mechanism 9, an orbital mechanism 12, an orbital switching mechanism 14, and a guide shoe 16.

[0016] The main body housing 2 is a support frame that directly or indirectly holds various members. The main housing 2 includes a half housing 18 , a power transmission housing 20 , and a cover 22 .

[0017] The front portion of the half housing 18 is cylindrical. The rear portion of the half housing 18 is formed in a loop shape. The half housing 18 is made of plastic. The half housing 18 holds the motor 3 in its upper front portion. The half housing 18 has a motor housing portion 18M that houses the motor 3. The motor 3 has a motor case 3a. The motor case 3a is the outer shell of the motor 3. The motor case 3a is cylindrical. The front of the motor case 3a is open. The half housing 18 is connected to the power transmission housing 20 via the motor case 3a. The half housing 18 is split into halves and has a left half housing 18a and a right half housing 18b. The left housing half 18a has a plurality of screw bosses (not shown). The right housing half 18b has a plurality of screw holes 24. The arrangement of the screw holes 24 corresponds to the arrangement of the screw bosses. The right housing half 18b is fixed to the left housing half 18a by inserting a plurality of screws 28 into the screw bosses and the screw holes 24 so as to extend in the left-right direction. The rear part of the loop extending in the vertical direction in the half housing 18 is a first grip portion 30. The first grip portion 30 is held by the user. Incidentally, the half housing 18 does not have to be split into halves, and may be, for example, a single unit.

[0018] A main switch 32 is held on the upper part of the first grip portion 30. The main switch 32 has a trigger 33 and a main switch body 34 . The trigger 33 is exposed at the front of the upper part of the first grip part 30. A user can pull (move rearward) the trigger 33 with a fingertip. The trigger 33 is disposed in front of the main switch body part 34. The trigger 33 is connected to the main switch body part 34. The main switch body 34 is disposed within the upper portion of the first grip portion 30. The main switch body 34 is switched on and off by operating the trigger 33. The main switch body 34 is turned on when the trigger 33 is pulled to a predetermined amount or more. The main switch body 34 also transmits a signal (e.g., a resistance value) that changes depending on the amount of pulling of the trigger 33 that is equal to or greater than the predetermined amount. The trigger 33 switches the motor 3 on and off via the main switch body 34. The trigger 33 is a switch operation unit that operates to turn the motor 3 on and off.

[0019] A lock-off button 35 is provided above the trigger 33. The lock-off button 35 is in the shape of a plate extending in the left-right direction. The left and right parts of the lock-off button 35 are exposed from the half-split housing 18. The lock-off button 35 can be slid to the right by pressing its left part, and can be slid to the left by pressing its right part. When the lock-off button 35 is slid to the right and positioned on the right side, it prevents the trigger 33 from being pulled. This prevents the motor 3 from being turned on. When the lock-off button 35 is slid to the left and positioned on the left side, it allows the trigger 33 to be pulled. This allows the motor 3 to be turned on.

[0020] A speed change dial 36 is provided in front of the lock-off button 35. The speed change dial 36 is disk-shaped and extends in all directions, and can be rotated. An upper portion of the speed change dial 36 is exposed from the half housing 18. The speed change dial 36 transmits a signal according to the rotation position (angle).

[0021] The half housing 18 holds a control circuit board 42 below the motor 3 . The control circuit board 42 controls the motor 3. The control circuit board 42 is equipped with at least a microcomputer and a plurality of (six or twelve) switching elements. The control circuit board 42 is disposed below the motor 3. The control circuit board 42 is in an oblique position, more specifically, in a position with the front side raised.

[0022] A rear lower portion 18E of the half housing 18 is recessed upward with respect to a front lower portion 18F of the half housing 18. A battery mounting portion 50 is provided in a lower rear portion 18E of the half housing 18. The battery 54 is attached to the battery attachment section 50 by sliding it from the rear side to the front. The attached battery 54 is electrically connected to the motor 3 via the control circuit board 42. The battery 54 supplies power to the motor 3.

[0023] The power transmission housing 20 directly or indirectly supports each of the reciprocating motion conversion mechanism 5, the slider 6, the counterweight mechanism 9, the orbital mechanism 12, and the orbital switching mechanism 14. The power transmission housing 20 accommodates the reciprocating motion conversion mechanism 5. The power transmission housing 20 is made of metal. The power transmission housing 20 is connected to the front side of the half housing 18. The power transmission housing 20 is split into halves and has a cylindrical shape with openings at the front and rear. The power transmission housing 20 is made of aluminum (including alloys). Since the power transmission housing 20 houses the reciprocating motion conversion mechanism 5, it can also be regarded as a conversion mechanism housing. The power transmission housing 20 may be made of a metal other than aluminum. The power transmission housing 20 includes an upper power transmission housing 20a, a lower power transmission housing 20b, and a bearing retainer 20c. The upper power transmission housing 20a is fixed to the lower power transmission housing 20b by a plurality of vertical screws (not shown). The rear end of the lower power transmission housing 20b is attached to the front end of the half housing 18 by a plurality of front-rear screws (not shown) that extend forward from the motor case 3a.

[0024] The cover 22 is cylindrical. The cover 22 is attached to the exterior of the power transmission housing 20. The cover 22 is disposed outside the power transmission housing 20. The cover 22 is made of an elastic body (rubber), and is provided on the outside of the power transmission housing 20 as a thermally or electrically insulating cover. The cover 22 does not have to be included as a component of the main body housing 2. The cover 22 may also be made of plastic. The rear end of the cover 22 covers the front end of the half-housing 18. The cover 22 is continuous with the half-housing 18 on its outer surface. Furthermore, an orbital switching lever hole 58 is provided on the rear left portion of the cover 22 (FIG. 2). The orbital switching lever hole 58 is widened in all directions. On the other hand, the lower part of the cover 22, i.e., the front part of the main body housing 2, forms a second grip part 60. The second grip part 60 is held by the user. At least one of the number of sections of the main housing 2, the size of each section of the main housing 2, and the shape of each section of the main housing 2 can be changed in various ways. For example, the rear part of the half housing 18 may be a handle housing separate from the half housing 18. Also, the battery attachment section 50 may be separate from the half housing 18.

[0025] Furthermore, a light 62 is disposed between the upper front portion of the power transmission housing 20 and the upper front portion of the cover 22. The light 62 has an LED board. The LED board has an LED mounted thereon. The light 62 emits light and projects it forward. The light 62 can irradiate the vicinity of the cutting position in front of the slider 6.

[0026] The motor 3, the main switch body 34, the speed change dial 36, and the light 62 are each electrically connected to the control circuit board 42 by a plurality of lead wires (not shown). A main body 64 of the reciprocating saw 1 is formed by the part of the half housing 18 that holds the motor 3 (the part outside the motor 3), the power transmission housing 20, various members held by these, and the cover 22.

[0027] The motor 3 is electrically driven. The motor 3 is a brushless motor. The motor 3 is DC driven. The motor 3 includes a motor case 3 a, a stator 66 , and a rotor 67 .

[0028] The motor case 3a is held in a half housing 18. The stator 66 has a cylindrical shape and includes a plurality of (six) coils 66C. The rotor 67 is disposed inside the stator 66. The motor 3 is of an inner rotor type. The rotor 67 has a motor shaft 68 . The motor shaft 68 is cylindrical and extends in the front-rear direction. The motor shaft 68 is made of metal. The motor shaft 68 rotates around its own axis. The front end of the motor shaft 68 reaches into the rear end of the power transmission housing 20. A pinion gear portion 68a is formed at the front end of the motor shaft 68. The pinion gear portion 68a has a plurality of teeth.

[0029] Further, a motor front bearing 69 is provided behind the pinion gear portion 68a. The motor front bearing 69 is disposed around the front portion of the motor shaft 68. The motor front bearing 69 supports the motor shaft 68 rotatably about its axis. The motor front bearing 69 is carried at the rear of the lower power transmission housing 20b. A motor rear bearing (not shown) is provided around the rear end of the motor shaft 68. The motor rear bearing supports the motor shaft 68 so that it can rotate about its axis. The motor rear bearing is held by the motor case 3a.

[0030] The fan 4 is disposed around the center of the motor shaft 68, behind the motor front bearing 69, and in front of the rotor 67 and stator 66. The fan 4 is a centrifugal fan having multiple blades. The fan 4 pushes air outward in the radial direction when it rotates. The fan 4 is fixed integrally to the motor shaft 68, and can rotate integrally with the motor shaft 68. The fan 4 is provided on the motor shaft 68. The fan 4 is held in the half housing 18 via the rotor 67 and the lower power transmission housing 20b. In front of the fan 4, a lower power transmission housing 20b is disposed. The fan 4 may also be a component of the motor 3 .

[0031] The reciprocating motion conversion mechanism 5 is a power transmission mechanism that transmits the power of the motor 3 to the slider 6. The reciprocating motion conversion mechanism 5 transmits the rotational motion of the motor shaft 68 of the motor 3 to the slider 6. The reciprocating motion conversion mechanism 5 is held in the power transmission housing 20. The reciprocating motion conversion mechanism 5 is interposed between the motor 3 and the slider 6. The reciprocating motion converting mechanism 5 includes a bevel gear 70, a torque limiting mechanism 72, an intermediate shaft 74, a crank base 76, and a crank cam 78.

[0032] The bevel gear 70 has a disk shape that extends in the front-rear and left-right directions, and has bevel teeth (not shown) on the periphery of its upper surface. The bevel gear 70 meshes with the pinion gear portion 68a. The bevel gear 70 rotates around an imaginary rotation axis in the up-down direction that passes through the center of the front-rear and left-right directions.

[0033] The torque limit mechanism 72 is interposed between the bevel gear 70 and the intermediate shaft 74 . The torque limit mechanism 72 transmits power from the bevel gear 70 to the intermediate shaft 74. When an excessive load is applied from the intermediate shaft 74 side, the upper and lower horizontal plates, which are in close contact with each other due to the biasing force of an elastic body, separate from each other against the biasing force, thereby protecting the bevel gear 70 and the motor 3 from the load.

[0034] The intermediate shaft 74 is a cylindrical member that extends vertically. The intermediate shaft 74 is supported by an upper intermediate bearing 80 and a lower intermediate bearing 82 so as to be rotatable about the same imaginary rotation axis as the bevel gear 70 (FIGS. 2 and 3). The upper intermediate bearing 80 is held in the lower power transmission housing 20b. The lower intermediate bearing 82 is a needle bearing. The lower intermediate bearing 82 is held by a dish-shaped bearing retainer 20c. The bearing retainer 20c is fixed to the lower power transmission housing 20b by a plurality of screws 86 (only one of which is shown in FIG. 3) in the vertical direction.

[0035] The crank base 76 is a crank-shaped member. The lower part of the crank base 76 is a cylindrical part 76A, which is fixed to the upper part of the intermediate shaft 74 by a screw. The central portion of the crank base 76 is a plate-shaped portion 76B that extends in the front-rear and left-right directions. The upper part of the crank base 76 is formed as an eccentric disk part 76C whose center is offset from the imaginary central axis of the lower part of the crank base 76 and which extends in the front-rear and left-right directions.

[0036] The crank cam 78 has a crank cam body 90 , an eccentric pin 92 , a barrel roller 94 , and a bearing 96 . The crank-cam body 90 is disk-shaped and extends forward, backward, left, and right. The imaginary central axis of the crank-cam body 90 in the vertical direction coincides with the same imaginary rotation axis as the bevel gear 70. A connecting portion 97 is formed at the bottom of the crank-cam body 90, which protrudes cylindrically downward from other portions. The eccentric disk portion 76C of the crank base 76 is connected to the connecting portion 97. A cam portion 98 is formed on the periphery of the upper surface of the crank-cam body 90. The cam portion 98 protrudes upward from adjacent portions. The cam portion 98 is ring-shaped when viewed from above. The height of the cam portion 98 in the vertical direction gradually changes along the circumferential direction. That is, the upper surface of the cam portion 98 forms a cam surface 99. The eccentric pin 92 is cylindrical and extends in the vertical direction. The lower part of the eccentric pin 92 is inserted into a vertical hole provided in the crank-cam body 90. The hole is offset in the radial direction from the imaginary central axis of the crank-cam body 90. The barrel-shaped roller 94 is a cylindrical member. The outer surface of the barrel-shaped roller 94 bulges outwardly so that the diameter increases toward the center in the vertical direction. The barrel-shaped roller 94 is provided on the upper part of the eccentric pin 92 via a bearing 96. The barrel-shaped roller 94 is supported so as to be rotatable around an imaginary rotation axis in the vertical direction. The bearing 96 is a needle bearing.

[0037] FIG. 5 is a cross-sectional view taken along line AA in FIG. 3. FIG. 6 is a cross-sectional view taken along line BB in FIG. 3. FIG. 7 is an exploded perspective view of the slider 6 and release mechanism 7 as viewed from the upper left rear. FIG. 8 is an exploded perspective view of the slider 6 and release mechanism 7 as viewed from the upper right front. FIG. 9A is a central vertical cross-sectional view of the blade holding portion 102 of the slider 6. FIG. 9B is a horizontal cross-sectional view of the central portion of the holding pin 113 of the blade holding portion 102. In FIGS. 1 to 9B, the blade holding portion 102 is in a blade standby state in which blade B is on standby. The slider 6 has a slider body 100 and a blade holding portion 102 serving as an end tool holding portion. The front end portion of the slider 6 can protrude from the front end of the power transmission housing 20. The slider body 100 is cylindrical and extends in the front-rear direction. A barrel-shaped roller receiving portion 104 is provided at the rear of the slider body 100. The barrel-shaped roller receiving portion 104 is an elongated cylinder with a bottom that extends in the left-right direction. The barrel-shaped roller receiving portion 104 is open downward. The barrel-shaped roller receiving portion 104 receives the barrel-shaped rollers 94. When the crank cam 78 rotates, the barrel-shaped roller 94 rotates eccentrically. The front-rear component of the movement of the barrel-shaped roller 94 causes the slider body 100 to reciprocate in the front-rear direction via the barrel-shaped roller support portion 104. The left-right component of the movement of the barrel-shaped roller 94 is a relative movement of the barrel-shaped roller 94 within the barrel-shaped roller support portion 104, and is not transmitted to the slider body 100. The blade holding portion 102 holds the blade B as an end tool. The blade B holding portion 102 automatically holds the blade B simply by inserting the rear end portion of the blade B into the blade B holding portion 102 (one-touch attachment). The blade holding portion 102 bulges outwardly and upwardly and downwardly with respect to the slider body 100. The slider 6 is the output portion. The blade B is a tool tip. The blade B is a long plate-like shape, and extends forwards and backwards when attached. The blade B has a blade BE on one long side. The blade BE is a sawtooth. The blade B is attached with the blade BE facing downwards. The blade B may also be attached with the blade BE facing upwards. The blade B may also have blades BE on both long sides. The tool tip may be something other than the blade B.

[0038] The blade holding portion 102 of the slider 6 has a push pin 110, a compression spring for the push pin 111, a guide sleeve 112, a holding pin 113, a compression spring for the holding pin 114, an auxiliary pin 115, a cam sleeve 116, a retaining ring 117, an auxiliary sleeve 118, and a torsion spring 119.

[0039] The front end of the slider body 100 is formed with a slit 120, a first holding pin hole 122, a first auxiliary pin hole 123, and a step portion . The slit 120 is wide in the front-rear and up-down directions. The slit 120 has a width (size in the left-right direction) that is slightly larger than the thickness of the blade B. The central portion of the slit 120 in the up-down direction is provided with an expanded space portion 120E in which the space is expanded to the left compared to other portions. The first retaining pin hole 122 is disposed on the left side of the slit 120 and communicates with the slit 120. The first retaining pin hole 122 extends to the left and right. The left portion of the first retaining pin hole 122 has a larger diameter than the right portion of the first retaining pin hole 122. The first auxiliary pin hole 123 is disposed on the right side of the slit 120 and communicates with the slit 120. The first auxiliary pin hole 123 extends left and right. The first auxiliary pin hole 123 faces the first retaining pin hole 122. A rib 125 is formed on the left side of the center of the first auxiliary pin hole 123, protruding radially inward relative to other portions. The outer diameter of the front end of the slider body 100 is smaller than the outer diameter of the rear portion, and a step 124 is formed at the portion where the outer diameter of the slider body 100 changes.

[0040] The push pin 110 is disposed within the slit 120, in the center of the slit 120 in the up-down direction. The push pin 110 extends forward and backward. The cross section of the push pin 110 is "D-shaped." The front left part of the push pin 110 is provided with a recess 110D that is recessed rightward from the rear part. The part of the push pin 110 rearward of the recess 110D is disposed within the spatial expansion part 120E of the slit 120. The push pin compression spring 111 is provided in the slit 120, in the center of the slit 120 in the up-down direction. The left part of the push pin compression spring 111 is disposed in the space enlargement part 120E of the slit 120. The push pin compression spring 111 is an elastic body, and is a coil spring. The push pin compression spring 111 is disposed on the rear side of the push pin 110. The rear end of the push pin compression spring 111 is disposed at the bottom of the rear end of the slit 120. The front end of the push pin compression spring 111 is in contact with the push pin 110. The push pin compression spring 111 is interposed between the push pin 110 and the slider body 100. The push pin compression spring 111 biases the push pin 110 forward.

[0041] The guide sleeve 112 is cylindrical. The guide sleeve 112 is disposed outside the front end portion of the slider body 100. The axial direction of the guide sleeve 112 is the front-rear direction. A circular recess 112G is formed on the outer surface of the front part of the guide sleeve 112. The groove 112G is recessed radially inward relative to the periphery. The groove 112G is formed so as to extend substantially around the outer surface of the front part of the guide sleeve 112. The guide sleeve 112 also has a second retaining pin hole 126 and a second auxiliary pin hole 128 in the center. The second retaining pin hole 126 is disposed in the left portion of the guide sleeve 112. The second retaining pin hole 126 extends left and right. The second retaining pin hole 126 overlaps with the first retaining pin hole 122. The diameter of the second retaining pin hole 126 is equal to or larger than the diameter of the left portion of the first retaining pin hole 122. The second auxiliary pin hole 128 is disposed on the right side of the guide sleeve 112. The second auxiliary pin hole 128 extends left and right. The second auxiliary pin hole 128 faces the second retaining pin hole 126. The diameter of the second auxiliary pin hole 128 is equal to the diameter of the first auxiliary pin hole 123 on the right side of the rib 125.

[0042] The retaining pin 113 is disposed inside the first retaining pin hole 122 and the second retaining pin hole 126. The retaining pin 113 is cylindrical and extends left and right. The diameter of the central portion of the retaining pin 113 is the same as the diameter of the right portion of the first retaining pin hole 122. The diameter of the right end portion of the retaining pin 113 is smaller than the diameter of the other portions. Therefore, a step 113S is formed at the left end portion of the retaining pin 113 (a stepped pin). The right end portion of the retaining pin 113 has a tapered shape that becomes thinner toward the right. In addition, the diameter of the left end portion of the retaining pin 113 is larger than the diameter of the other portions, and the left end portion of the retaining pin 113 forms a head portion 113H that is larger in diameter than the other portions. The left surface of the retaining pin 113 forms a curved surface 113C that bulges leftward. The retaining pin compression spring 114 is an elastic body, and is a coil spring. The right end of the retaining pin compression spring 114 contacts the enlarged diameter portion of the first retaining pin hole 122. The left end of the retaining pin compression spring 114 contacts the right surface of the head 113H of the retaining pin 113. The retaining pin compression spring 114 is interposed between the retaining pin 113 and the slider body 100. The retaining pin compression spring 114 urges the retaining pin 113 to the right. The auxiliary pin 115 is disposed inside the first auxiliary pin hole 123 and the second auxiliary pin hole 128. The auxiliary pin 115 is cylindrical and extends left and right. The left end of the auxiliary pin 115 can contact the rib 125 of the first auxiliary pin hole 123. The right end of the auxiliary pin 115 protrudes rightward from the second auxiliary pin hole 128 to form an exposed portion 115A. The diameter of the auxiliary pin 115 is the same as the diameter of the right portion of the first auxiliary pin hole 123 and the diameter of the second auxiliary pin hole 128. The auxiliary pin 115 connects the slider body 100 and the guide sleeve 112.

[0043] The cam sleeve 116 is cylindrical. The axial direction of the cam sleeve 116 is the front-rear direction. The cam sleeve 116 is disposed outside the guide sleeve 112, the retaining pin 113, and the auxiliary pin 115. The cam sleeve 116 is rotatable around the slider body 100 and the guide sleeve 112. A first protruding portion 116E is formed from the top to the left of the cam sleeve 116. The first protruding portion 116E protrudes radially outward relative to other portions of the cam sleeve 116. A cam surface 116C is formed on the inner surface of the first protruding portion 116E. The diameter of the cam surface 116C gradually increases from the bottom to the counterclockwise direction (mounting direction C) when viewed from the front. A curved surface 113C of the head 113H of the holding pin 113 contacts the cam surface 116C. When the blade holding portion 102 is not receiving the blade B (blade standby state), the curved surface 113C contacts the side of the cam surface 116C that is closer to the maximum diameter portion. The cam sleeve 116 also has a second overhang 116F. The second overhang 116F extends from the upper portion to the right portion of the cam sleeve 116. The second overhang 116F overhangs radially outward relative to other portions of the cam sleeve 116. A space is formed between the second overhang 116F and the guide sleeve 112. A first end 116X on the upper side of the second overhang 116F has a surface extending radially and in the front-rear direction. A second end 116Y on the lower side of the second overhang 116F has a surface extending radially and in the front-rear direction. Furthermore, the cam sleeve 116 has a projection 134 that projects outward in the radial direction. The projection 134 is disposed on the outer side of the second protruding portion 116F. In the blade standby state, the projection 134 is disposed at the upper right. In addition, a plurality of protrusions 116B that protrude radially inward from the rest of the inner surface are formed on the inner surface of the opening at the rear end of the cam sleeve 116. The protrusions 116B are aligned in the circumferential direction.

[0044] The retaining ring 117 is ring-shaped. The retaining ring 117 is inserted into the groove 112G and is fixed to the outside of the guide sleeve 112. The retaining ring 117 is disposed on the front side of the cam sleeve 116 and prevents the cam sleeve 116 from moving forward. The auxiliary sleeve 118 is cylindrical. The axial direction of the auxiliary sleeve 118 is the front-rear direction. The auxiliary sleeve 118 is disposed outside the slider body 100 and can rotate around the slider body 100. The auxiliary sleeve 118 is disposed on the front side of the step portion 124. The step portion 124 suppresses the rearward movement of the auxiliary sleeve 118. The outer surface of the opening at the front end of the auxiliary sleeve 118 is formed with a plurality of recesses 118P that are recessed radially inward from the other inner surfaces. The rear end of the auxiliary sleeve 118 is inserted inside the opening at the rear end of the cam sleeve 116. Each recess 118P of the auxiliary sleeve 118 is inserted into the corresponding protrusion 116B of the cam sleeve 116. The auxiliary sleeve 118 rotates together with the cam sleeve 116. The torsion spring 119 is ring-shaped and is an elastic body. The rear end of the torsion spring 119 forms a connecting portion 119A that extends vertically at the center in the left-right direction and is inserted into the slit 120. The connecting portion 119A is disposed between the bottom of the rear end of the slit 120 and the rear end of the push pin compression spring 111. The connecting portion 119A is fixed to the slider body 100. The portion of the torsion spring 119 other than the connecting portion 119A is disposed around the front end of the slider body 100 and on the rear side of the auxiliary sleeve 118. The front end of the torsion spring 119 is inserted into a hole in the front-rear direction of the auxiliary sleeve 118 and is fixed to the auxiliary sleeve 118. The torsion spring 119 biases the auxiliary sleeve 118 in the circumferential direction, that is, in the counterclockwise direction when viewed from the front (mounting direction C).

[0045] The blade B has a retaining hole BH at its rear end. The diameter of the retaining hole BH is slightly larger than the diameter of the left end of the retaining pin 113. In addition, the corner of the rear end of blade B on the opposite side to blade BE is cut out. The part of the rear end of blade B on the same side as blade BE protrudes rearward to form protruding piece BJ. The upper rear edge of blade B above protruding piece BJ forms shoulder BS. Furthermore, the blade B has a protrusion BB at the rear end. The protrusion BB is disposed on the opposite side to the edge BE. The protrusion BB protrudes upward with respect to the other portion of the upper side of the blade B.

[0046] Fig. 10A is a central vertical cross-sectional view of the blade holding portion 102 (blade attached state). Fig. 10B is a cross-sectional view of the central portion of the holding pin 113 of the blade holding portion 102 (blade attached state). Fig. 11A is a central vertical cross-sectional view of the blade holding portion 102 (blade removed state). Fig. 11B is a cross-sectional view of the central portion of the holding pin 113 of the blade holding portion 102 (blade attached state). When the rear end of blade B is not inserted into slit 120 (FIGS. 9A and 9B), the front end of push pin 110 is inserted into the left side of holding pin 113. Holding pin 113 moves leftward to a retracted state. In addition, exposed portion 115A of auxiliary pin 115 is adjacent to second end 116Y of second protruding portion 116F.

[0047] When the rear end of the blade B is inserted into the slit 120 , the push pin 110 is pushed rearward by the shoulder BS of the blade B against the biasing force of the push pin compression spring 111 . When the rear end of blade B further advances rearward and the holding hole BH of blade B is located to the right of the holding pin 113, the cam surface 116C of the cam sleeve 116 pushes the holding pin 113 leftward against the biasing force of the holding pin compression spring 114. That is, the cam sleeve 116 is biased by the torsion spring 119 via the auxiliary sleeve 118. The biasing direction of the torsion spring 119 is the mounting direction C. Then, when the holding hole BH of blade B is located to the left of the holding pin 113 and the holding pin 113 becomes movable to the left, the cam sleeve 116 rotates in the mounting direction C. Then, the curved surface 113C of the holding pin 113 comes into contact with a portion of the cam surface 116C that protrudes further inward (a portion with a smaller diameter, a portion close to the minimum diameter portion of the cam surface 116C). Therefore, the retaining pin 113 is pushed to the left by the cam surface 116C. The portion of holding pin 113 pushed leftwardly to the left of step 113S enters holding hole BH of blade B to hold (attach) blade B (blade attached state, FIGS. 10A and 10B). Therefore, the blade B is automatically held in place simply by inserting it into the slit 120 (one-touch attachment). When the holding pin 113 holds the blade B, the protrusion 134 of the cam sleeve 116 is disposed on the right side due to the rotation of the cam sleeve 116. In addition, the exposed portion 115A of the auxiliary pin 115 is adjacent to the first end 116X of the second protruding portion 116F.

[0048] The protrusion BB of the blade B held by the blade holding portion 102 abuts against the front end surface of the guide sleeve 112 . The guide sleeve 112 is fixed in a state in which its movement in the front-rear direction and its rotation are restricted with respect to the slider body 100 by an auxiliary pin 115 separate from the retaining pin 113. The retaining pin 113 is disposed in a first retaining pin hole 122 whose left portion is enlarged in diameter.

[0049] Then, the blade B held by the blade holding portion 102 is removed from the blade holding portion 102 in cooperation with the release mechanism 7. The release mechanism 7 includes a release drum 140, a tension spring 142 which is an elastic body, and a plurality of (two) ring springs 144A and 144B.

[0050] The release drum 140 is cylindrical and disposed around the cam sleeve 116. The release drum 140 is adjacent to the blade holding portion 102. The release drum 140 is an operation drum that is operated by a user to operate the removal (release) of the blade B from the blade holding portion 102. The release drum 140 is made of synthetic resin. Therefore, compared to a case where the release drum 140 and the surrounding members are all made of metal, the resistance to external electric shock is better. In addition, even if the release drum 140 has a complex shape, it is easier to form it.

[0051] The release drum 140 has a release drum main body 140M, an inward protruding portion 148, an operation piece 150, and a locking portion 154. The inward protrusion 148 is disposed on the inner surface of the release drum 140, and protrudes radially inward from other portions of the inner surface of the release drum 140. The inward protrusion 148 is disposed on the right portion of the release drum 140. The operation piece 150 is disposed on the right side of the release drum 140. The operation piece 150 is disposed radially outward from the inner raised portion 148. The operation piece 150 protrudes radially outward from the other outer surface. The operation piece 150 has a trapezoidal cross section. The tip of the operation piece 150 is thinner than the base of the operation piece 150. In the blade standby state, the operation piece 150 extends from the upper left to the lower right, and extends forward and backward. The operation piece 150 is formed integrally with the other portion of the release drum 140 (the cylindrical release drum main body portion 140M). The operation piece 150 protrudes to the right from the first operation piece hole 20H of the power transmission housing 20 and the second operation piece hole 22H of the cover 22. The locking portion 154 is disposed on the outer side of the upper right portion of the release drum 140. The locking portion 154 protrudes radially outward from the other outer surface. The locking portion 154 has a hook shape. The locking portion 154 is formed integrally with the release drum main body 140M. Further, a circular recess 140G1 is formed in the front part of the outer surface of the release drum main body 140M. The groove 140G1 is recessed radially inward with respect to an adjacent part of the release drum main body 140M. An imaginary plane including the groove 140G1 is perpendicular to an imaginary central axis of the release drum main body 140M. On the other hand, a circular recess 140G2 is formed in the rear part of the outer surface of the release drum main body 140M. The groove 140G2 is recessed radially inward with respect to an adjacent part of the release drum main body 140M. An imaginary plane including the groove 140G2 is perpendicular to an imaginary central axis of the release drum main body 140M. Furthermore, a flange portion 140F is formed at the front end of the release drum main body portion 140M, the flange portion 140F extending radially outward from the adjacent portion. 140G1 is disposed on the rear side of the flange portion 140F.

[0052] The tension spring 142 is a coil spring. The tension spring 142 is disposed on the outer side in the circumferential direction of the release drum 140, and extends in the circumferential direction of the release drum main body 140M. The tension spring 142 is disposed on the upper side of the release drum main body 140M. A first end of the tension spring 142 has a hook shape and is engaged with a stopper 154 of the release drum 140. A second end of the tension spring 142 has a hook shape and is fixed to the upper power transmission housing 20a.

[0053] The ring spring 144A as a ring member is an elastic body and is a single spring. The size (width) of the ring spring 144A in the front-rear direction is 1 mm (millimeter). The ring spring 144A is made of iron (including alloys), more specifically, stainless steel. The ring spring 144A is "C" shaped when viewed from the front, has a slit, and is not a completely closed ring. The ring spring 144A is fitted into a groove 140G1 of the release drum 140. The radially inner part of the ring spring 144A is in the groove 140G1. The radially outer part of the ring spring 144A protrudes radially outward from the groove 140G1. The ring spring 144B as a ring member is an elastic body and is a single spring. The size (width) of the ring spring 144B in the front-rear direction is 1 mm. The ring spring 144B is made of iron (including alloys), more specifically, stainless steel. The ring spring 144B is "C" shaped when viewed from the front, has a slit, and is not a completely closed ring. The ring spring 144B is fitted into the groove 140G2 of the release drum 140. The radially inner part of the ring spring 144B is in the groove 140G2. The radially outer part of the ring spring 144B protrudes radially outward from the groove 140G2. The arrangement of the slits in at least one of the ring springs 144A, 144B is not limited to that shown in FIG. 4. At least one of the ring springs 144A, 144B may be a completely closed ring or a spring having more than one ring. At least one of the ring springs 144A, 144B may not have elasticity and may be attached to the release drum 140 by adhesion or the like. At least one of the ring springs 144A, 144B may be made of iron other than stainless steel or may be made of metal other than iron. In addition, at least one of the ring springs 144A, 144B may be provided on the inner surface of the power transmission housing 20. There may be one ring spring 144A, 144B, or there may be three or more ring springs.

[0054] When the tension spring 142 is in a state where it is slightly stretched from its natural length, the inward protrusion 148 of the release drum 140 is not in contact with the projection 134 of the cam sleeve 116 in the blade attached state. At this time, the operation piece 150 of the release drum 140 is in contact with the lower ends of the first operation piece hole 20H and the second operation piece hole 22H. The rotational position of the release drum 140 at this time is the initial rotational position of the release drum 140. Note that the tension spring 142 at this time may be in another state, such as a natural length state. The user can rotate the release drum 140 around a virtual central axis in the front-rear direction of the release drum 140 by operating the operation piece 150 located at the bottom upward against the biasing force of the tension spring 142. In this case, the operation piece 150 rotates up to the maximum until it comes into contact with the upper ends of the first operation piece hole 20H and the second operation piece hole 22H. By such rotation of the release drum 140, the inward protrusion 148 comes into contact with the protrusion 134 of the cam sleeve 116, rotating the protrusion 134 and rotating the cam sleeve 116 in the opposite direction to the mounting direction C. By this rotation of the cam sleeve 116, the curved surface 113C of the retaining pin 113 is positioned inside the large-diameter portion of the cam surface 116C, and the retaining pin 113 retreats to the right due to the biasing force of the retaining pin compression spring 114 and comes out of the retaining hole BH of the blade B (removal). Then, the push pin 110 moves forward by the biasing force of the push pin compression spring 111, pushing the removed blade B forward and entering the right side of the holding pin 113 (FIGS. 11A and 11B). The push pin 110 smoothly enters the right side of the holding pin 113 due to the recess 110D at the front end of the push pin 110. Therefore, the release drum 140 of the release mechanism 7 works in conjunction with the inner blade holding part 102, and by operating the operating piece 150 upward, the blade B is released from the blade holding part 102. Rotation of the protrusion 134 is the operation of removing the blade B from the blade holding part 102, i.e., the operation of removing the blade holding part 102. The removal operation is an operation related to attaching and detaching the blade B. The release mechanism 7 (release drum 140) operates the operation of removing the blade holding part 102 by rotating itself. Incidentally, the protrusion 134 of the blade holding part 102 may perform the operation related to attaching the blade B. Also, the operation drum may operate the operation related to attaching the blade B. When the push pin 110 enters the right side of the retaining pin 113, the rightward movement of the retaining pin 113 is restricted. Therefore, the retaining pin 113 resists the biasing force of the torsion spring 119 in the mounting direction C and restricts the rotation of the cam sleeve 116 in the mounting direction C. The release drum 140 returns downward due to the biasing force of the tension spring 142 . In addition, in the reciprocating saw 1 according to the embodiment of the present disclosure, the user can attach the blade B with one touch, but other types of products are known that require the user to rotate the operation drum when attaching the blade B. In such products, the member corresponding to the holding pin 113 that enters the holding hole BH of the blade B retracts from the holding hole BH only when the user rotates the operation drum, and the member corresponding to the holding pin 113 does not retract when the user simply inserts the blade B for attachment. In such products, the operation drum is operated when attaching and releasing the blade B, so the frequency of operation of the operation drum is higher than that of the reciprocating saw 1. Therefore, the need to suppress the deterioration of the movement of the operation drum is higher than that of the reciprocating saw 1. In other words, the mechanism including the ring spring 144A for suppressing the deterioration of the movement of the operation drum adopted in the reciprocating saw 1 is more necessary in products in which the operation drum is operated even when the blade B is attached.

[0055] Fig. 12A is a central vertical cross-sectional view of the blade holding portion 102 (with the holding pin bottomed out), and Fig. 12B is a horizontal cross-sectional view of the central portion of the holding pin 113 of the blade holding portion 102 (with the holding pin bottomed out). Depending on at least one of the type of blade B and vibration, the right side of the push pin 110 may not be pressed by the retaining pin 113 even though the blade B is not inserted in the blade retaining portion 102. At this time, the head 113H of the retaining pin 113 is in a position beyond the end of the cam surface 116C in the direction opposite to the mounting direction C, and the retaining pin 113 is pressed to the right by the inner surface of the cam sleeve 116 other than the cam surface 116C (bottomed out state). In the bottomed-out state, wear on the inner surface of the cam sleeve 116 and / or variations in assembly accuracy may cause the cam sleeve 116 to rotate freely from the state shown in Figures 12A and 12B in the direction opposite to the mounting direction C relative to the retaining pin 113. If such rotation occurs and the protrusion 134 goes beyond the inner raised portion 148 of the release drum 140 to the left side of the inner raised portion 148 (the side moving forward in the mounting direction C from the inner raised portion 148), the inner raised portion 148 will not engage with the protrusion 134 even if the operating piece 150 of the release drum 140 is operated, and the release operation of the blade B cannot be performed. However, in the reciprocating saw 1, the exposed portion 115A of the auxiliary pin 115 abuts against the first end 116X of the second protruding portion 116F, thereby preventing such idling. Therefore, in the reciprocating saw 1, the holding pin 113 is prevented from bottoming out and spinning freely, and the release operation is prevented from becoming impossible.

[0056] Fig. 13 is an exploded perspective view of the front part of the upper power transmission housing 20a, the release mechanism 7, and the front part of the lower power transmission housing 20b as viewed from above. Fig. 14 is an exploded perspective view of the front part of the upper power transmission housing 20a, the release mechanism 7, and the front part of the lower power transmission housing 20b as viewed from below. The release mechanism 7 is disposed within the cylindrical front end of the power transmission housing 20 . A first upper groove 160U having a semicircular arc shape extending left and right is formed on the front end inner surface of the upper power transmission housing 20a. The first upper groove 160U is recessed radially outward from the adjacent portion. Half of the flange portion 140F of the release drum 140 is inserted into the first upper groove 160U. In addition, a second upper groove 162U having a semicircular arc shape extending left and right is formed behind the first upper groove 160U. The second upper groove 162U is recessed radially outward from the adjacent portion. The tension spring 142 is inserted into the second upper groove 162U. A first upper cylindrical band portion 164U having a semicircular arc band shape is formed between the first upper groove 160U and the second upper groove 162U. A plurality (two places) of lightening holes 165U are provided behind the second upper groove 162U. A semicircular arc-shaped second upper cylindrical band portion 166U is disposed behind the lightening hole 165U. Furthermore, an upper semicircular arc wall 167U that protrudes radially inward in a semicircular arc shape and a wall 168 that has a central hole and extends up, down, left and right are disposed behind the second upper cylindrical band portion 166U. A plurality of (two) vent holes 169 are formed between the upper semicircular arc wall 167U and the wall 168, aligned left and right. A first lower groove 160D having a semicircular arc shape extending left and right is formed on the front end inner surface of the lower power transmission housing 20b. The first lower groove 160D is recessed radially outward from the adjacent portion. Half of the flange portion 140F of the release drum 140 is inserted into the first lower groove 160D. A vertical hole 160H is arranged at the lower end of the first lower groove 160D. The hole 160H allows chips and the like that have entered the first upper groove 160U and the first lower groove 160D to be discharged downward. In addition, a second lower groove 162D having a quarter-circular arc shape extending left and right is formed behind the first lower groove 160D. The second lower groove 162D is recessed radially outward from the adjacent portion. The second lower groove 162D is arranged at the left part of the lower power transmission housing 20b. The second lower groove 162D receives the locking portion 154 of the release drum 140. A first lower cylindrical band portion 164D having a semicircular arc shape is formed between the first lower groove portion 160D and the second lower groove portion 162D. A lightening hole 165D is provided behind the second lower groove portion 162D. A second lower cylindrical band portion 166D having a semicircular arc shape is disposed behind the lightening hole 165D. Furthermore, a lower semicircular arc wall 167D protruding radially inward in a semicircular arc shape is disposed behind the second upper cylindrical band portion 166U. The first upper groove portion 160U and the first lower groove portion 160D face each other and are continuous with each other. The second upper groove portion 162U and the second lower groove portion 162D face each other and are continuous with each other. The first upper cylindrical band portion 164U and the first lower cylindrical band portion 164D face each other and are continuous with each other. The second upper cylindrical band portion 166U and the second lower cylindrical band portion 166D face each other and are continuous with each other. The upper semicircular arc wall 167U and the lower semicircular arc wall 167D face each other and are continuous with each other. The first upper groove portion 160U and the first lower groove portion 160D, the first upper cylindrical band portion 164U and the first lower cylindrical band portion 164D, and the second upper groove portion 162U and the second lower groove portion 162D are adjacent to one another in the front-rear direction.

[0057] The release drum body 140M is disposed rearward of the first upper groove portion 160U and the first lower groove portion 160D and forward of the upper semicircular arc wall 167U and the lower semicircular arc wall 167D. An iron front ring spring 144A abuts against the aluminum first upper cylindrical band portion 164U and first lower cylindrical band portion 164D. An iron rear ring spring 144B abuts against the aluminum second upper cylindrical band portion 166U and second lower cylindrical band portion 166D. The release drum 140 contacts the power transmission housing 20 via the two ring springs 144A, 144B and does not basically contact the power transmission housing 20. This contact is maintained even when the release drum 140 rotates. These contacts prevent chips from entering behind the front ring spring 144A and in front of the rear ring spring 144B. Furthermore, even if chips are present between the release drum main body 140M and the power transmission housing 20, the release drum main body 140M contacts the power transmission housing 20 through the two ring springs 144A and 144B in a linear contact state with the power transmission housing 20, and the contact area is smaller than in the case of surface contact, etc., so that the release drum 140 is prevented from being caught by chips and becoming difficult to rotate. Furthermore, if the synthetic resin release drum 140 were to contact the aluminum power transmission housing 20 widely, the part of the release drum 140 that contacts the power transmission housing 20 may melt after long-term use. However, in the reciprocating saw 1, the metal ring springs 144A and 144B contact the power transmission housing 20, so that the release drum 140 is prevented from melting. In consideration of at least one of the viewpoints of reducing the contact area and suppressing dissolution of the synthetic resin release drum 140, the width of at least one of the ring springs 144A, 144B may be set to 4 mm or less, or 3 mm or less, 2 mm or less, or 1 mm or less. In addition to the ring springs 144A and 144B, one or more seal members such as elastic rings that suppress the intrusion of chips may be provided. At least one of the first upper cylindrical band portion 164U and the first lower cylindrical band portion 164D and the second upper cylindrical band portion 166U and the second lower cylindrical band portion 166D may have projections and recesses in the radial direction, and at least one of the ring springs 144A and 144B may contact the inwardly protruding portion. In this case, the contact area is further reduced.

[0058] The counterweight mechanism 9 is combined with the reciprocating motion conversion mechanism 5. The counterweight mechanism 9 has a metallic balancer 170 and a ring 172 . The balancer 170 is in the form of a plate extending in the front-rear and left-right directions, and has in its center a long hole 174 extending in the left-right direction. The portion of the balancer 170 in front of the long hole 174 is heavier than the portion behind the long hole 174. The connecting portion 97 of the crank cam 78 is inserted into the elongated hole 174 of the balancer 170 via a ring 172 . The balancer 170 reciprocates in the front-rear direction due to the rotation of the crank cam 78. The joint 97 is disposed on the opposite side of the center of the crank cam body 90 from the barrel roller 94. More specifically, the joint 97 and the barrel roller 94 are at an angle of about 175° with respect to the center of the front-rear and left-right of the crank cam body 90. Therefore, the part of the balancer 170 in front of the long hole 174 basically moves in the opposite direction to the slider 6 in the front-rear direction. Therefore, the vibration generated by the reciprocating motion of the slider 6 is suppressed by the balancer 170. That is, the balancer 170 acts as a counterweight by moving in the opposite direction to the front-rear motion of the slider 6. The left-right component of the movement of the joint 97 is the relative movement of the joint 97 in the long hole 174 and is not transmitted to the balancer 170. Moreover, the angle between the connecting portion 97 and the barrel-shaped roller 94 may be 180° or may be another angle.

[0059] The orbital mechanism 12 has a slider support body 180, a plurality (two pieces) of oilless bearings 181 as slider supports, a plurality (two pieces) of plates 182, a slider support shaft 183, a plurality of springs 184 as elastic bodies, a bearing 186, and a plurality of screws 190. A cylindrical slider support 191 is configured by the slider support main body 180, the oil-less bearings 181, the plates 182, the bearings 186, and the screws 190. The bearings 186 and the like may be removed from the components of the slider support 191. Furthermore, the components of the slider support 191 may include at least one of the slider support shaft 183 and the springs 184.

[0060] The slider support body 180 is made of metal and has a box shape that extends in the front-rear direction. Oilless bearings 181 are held at the front and rear inside the slider support body 180. The outer shape of the cross section of the oilless bearing 181 is square. The slider 6 passes through each oilless bearing 181 so as to be capable of reciprocating motion. An opening is provided in the center of the lower part of the slider support body 180, which includes a portion where the barrel-shaped roller 94 and the barrel-shaped roller support portion 104 can be located. The oil-less bearings 181 are disposed in front of and behind the opening. A rear plate 182 is fixed to the rear of the lower part of the slider support body 180, below the rear oilless bearing 181, by multiple (two on the left and right) screws 190 in the vertical direction. The rear plate 182 is made of metal and extends in the front-rear and left-right directions. The slider support body 180 holds the rear oilless bearing 181 from above. The rear plate 182 holds the rear oilless bearing 181 from below. A front plate 182 is fixed to the front of the lower part of the slider support body 180, below the front oilless bearing 181, by multiple screws 190 (two on the left and right) in the vertical direction. The front plate 182 is made of metal and extends in the front-rear and left-right directions. The slider support body 180 holds the front oilless bearing 181 from above. The front plate 182 holds the front oilless bearing 181 from below. It should be noted that the plate 182 and the screw 190 may be omitted.

[0061] The slider support shaft 183 passes through holes 162 provided on the left and right sides of the front lower part of the slider support main body 180. The slider support 191 is capable of swinging around the slider support shaft 183. The springs 184 are provided on the left and right sides of the upper rear portion of the slider support body 180. Each spring 184 extends in the vertical direction. The upper end of each spring 184 is held by the inner surface of the rear portion of the upper power transmission housing 20a.

[0062] The bearing 186 is provided behind the lower opening of the slider support body 180 and in front of the plate 182. The bearing 186 is a ball bearing. The inner race of the bearing 186 is held on the outer surface of the oilless bearing 181. The outer race of the bearing 186 is capable of contacting the cam portion 98 of the crank cam 78.

[0063] The orbital switching mechanism 14 has an orbital switching lever 192 as an orbital switching member. The orbital switching lever 192 has a lever body 193 as a shaft-shaped portion, and a knob portion 194 .

[0064] The lever body 193 is rod-like and axially extends to the left and right. The orbital switching lever 192 is held by the upper power transmission housing 20a in a state in which it can rotate around an imaginary central axis of a lever body 193. The imaginary central axis of the lever body 193 is parallel to the plate 182 with which it comes into contact. Lever body 193 has a first plane 196 as a support surface extending left and right, and a second plane 198 as a second orbital state surface extending left and right. First plane 196 and second plane 198 form a predetermined angle (about 100° in this case). The distance from an imaginary central axis to first plane 196 is greater than the distance from the imaginary central axis to second plane 198. When the orbital is in the first state (first orbital state), the orbital switching lever 192 is in a state in which the first plane 196 can come into contact with the rear lower part (rear plate 182) of the slider support 191. When the orbital switching lever 192 comes into contact with the plate 182, the first plane 196 is horizontal, unlike in FIG. 3 where the orbital is in the second state (second orbital state), the second plane 198 of the orbital switching lever 192 is horizontal and faces the rear lower part of the slider support 191 with a gap therebetween. In this case, the bearing 186 of the orbital mechanism 12 contacts the entire circumference of the cam surface 99 of the cam portion 98.

[0065] In the second orbital state, the bearing 186 also comes into contact with the lowest point of the cam surface 99 of the cam portion 98 due to the downward biasing force of each spring 184. The second plane 198 of the lever body 193 is still separated from the rear lower part of the slider support 191. Then, the slider support 191, the slider 6, and the blade B face upward (front up). The bearing 186 also comes into contact with the highest point of the cam surface 99. Then, the bearing 186 is pushed upward by the cam surface 99 against the biasing force of each spring 184, and the slider support 191, the slider 6, and the blade B face downward (front down). The height of the part of the cam surface 99 between the lowest point and the highest point in the circumferential direction gradually changes. Therefore, the bearing 186, which relatively follows the cam surface 99 due to the rotation of the crank cam 78, moves up and down. Therefore, the slider support 191, slider 6 and blade B repeat a front-up state, a state along the front-rear direction, a front-down state and a state along the front-rear direction, and the blade holding portion 102 performs an elliptical orbital motion. The orbital motion is associated with the reciprocating motion of the slider 6 in accordance with the circumferential distribution of the height of the cam surface 99 of the crank cam 78. Here, the distribution of the height of the cam surface 99 is adjusted so that when the slider 6 moves forward, the slider 6 is in a front-up state, and when the direction of movement of the slider 6 switches from forward to rearward (or when passing near the switching point), the slider 6 is in a state along the front-to-rear direction, and when the slider 6 moves rearward, the slider 6 is in a front-down state, and when the direction of movement of the slider 6 switches from rear to forward (or when passing near the switching point), the slider 6 is in a state along the front-to-rear direction. Even if the slider support 191 and the slider 6 change position upward or downward, the slider 6 can be sufficiently reciprocated by the barrel-shaped rollers 94 .

[0066] On the other hand, in the first orbital state, the rear portion of the slider support 191 is raised by the first flat surface 196 of the lever body 193, so that the bearing 186 does not contact the lowest point of the cam surface 99 or its adjacent portion. Therefore, compared to the second orbital state, the front rise of the slider 6 is suppressed. In contrast, the bearing 186 contacts the highest point of the cam surface 99 and its adjacent portion. The bearing 186 is in contact with approximately half of the cam portion 98, and is not in contact with the remaining portion due to the first flat surface 196 of the lever body 193. Thus, when the slider 6 moves rearward, the transition from a state along the front-rear direction to a state along the front-rear direction via a front-down state (semi-elliptical orbital motion of the blade holding portion 102 when the slider 6 moves rearward) occurs in the same manner as in the second orbital state, but when the slider 6 moves forward, the state of the slider 6 roughly along the front-rear direction is maintained. Therefore, in the first orbital state, the blade holding portion 102 performs a semi-elliptical orbital motion.

[0067] In the first orbital state, the blade holding portion 102 performs orbital motion in a range of approximately half a circumference (first range). In contrast, in the second orbital state, the blade holding portion 102 performs orbital motion in a range of the entire circumference (second range) that is wider than the range of approximately half a circumference (first range). In the first orbital state, orbital motion does not have to occur over the entire range, or the range of orbital motion (proportion of presence or absence) may be changed, for example, by making orbital motion occur in an elliptical arc in only one-quarter of the range and not in the remaining three-quarters of the range. Similarly, in the second orbital state, orbital motion may not occur over a portion of the range. In other words, the range in which orbital motion occurs can be changed in various ways as long as the range of orbital motion in the first orbital state (first range) is smaller than the range of orbital motion in the second orbital state (second range).

[0068] The knob portion 194 intersects with the lever body 193 at right angles here. The knob portion 194 is disposed to the left of the power transmission housing 20 and the cover 22 and is exposed to the outside. The knob portion 194 is disposed in the orbital switching lever hole 58 of the cover 22. The user can operate knob portion 194 to rotate orbital switching lever 192 around an imaginary central axis to switch the orbital state.

[0069] The guide shoe 16 is disposed adjacent to the blade B attached to the blade holding portion 102 . The guide shoe 16 is disposed in front of and below the slider 6 . The guide shoe 16 includes a shoe plate 200, a shoe supporter 206, and a plurality of (two) shafts 207. The shoe plate 200 is capable of contacting the workpiece. The shoe supporter 206 is disposed above a shoe supporter cover 208. The shoe supporter 206 is disposed inside the shoe supporter cover 208 so as to be able to slide back and forth. The shoe supporter cover 208 is fixed to the power transmission housing 20. Although the main body housing 2 does not include the shoe supporter cover 208, it may be treated as if it does. The shafts 207 are disposed on the left and right of the front end portion of the shoe supporter 206. The shafts 207 support the shoe plate 200 so that the shoe plate 200 is swingable around an axis in the left-right direction. The cross section of the shoe supporter 206 and the cross section of the shoe supporter cover 208 are each U-shaped. The shoe supporter 206 and the shoe supporter cover 208 are disposed between the front lower outer surface of the power transmission housing 20 and the front lower inner surface of the cover 22.

[0070] A shoe lever 210 is disposed on the outer side of the shoe supporter cover 208. The shoe lever 210 is equipped with a shoe supporter fixing shaft 212 in the left-right direction that passes above the shoe supporter cover 208 and the shoe supporter 206. The shoe lever 210 is rotatable around the shoe supporter fixing shaft 212 and can be opened and closed relative to the shoe supporter cover 208. When the shoe lever 210 is closed (facing the front-to-rear direction as shown in the drawing), the shoe supporter fixing shaft 212 tightens and fixes the shoe supporter 206. On the other hand, when the shoe lever 210 is open (facing the up-down direction), the shoe supporter 206 is released from the tightening by the shoe supporter fixing shaft 212. This allows the shoe supporter 206 and the shoe plate 200 to slide in the front-to-rear direction, making it possible to adjust the position of the guide shoe 16.

[0071] A pin 214 extending vertically is provided on the rear side of the shoe supporter fixing shaft 212. A spring 216 serving as an elastic body is interposed between the upper end of the pin 214 and the power transmission housing 20. The lower end of the pin 214 is located within the lower surface of the cover 22. The pin 214 can be raised by being pushed through the cover 22 against the elastic force of the spring 216. The lower part of the pin 214 is thinner than the central part. When the pin 214 is not raised, the central part of the pin 214 interferes with the shoe supporter 206 attempting to advance beyond a predetermined extent, suppressing the advancement of the shoe supporter 206 and preventing the guide shoe 16 from coming off. When the pin 214 is raised, the interference of the central part of the pin 214 with the shoe supporter 206 is eliminated, and the guide shoe 16 can be separated from other parts of the reciprocating saw 1.

[0072] An example of the operation of such a reciprocating saw 1 will now be described. The user sets the blade B on the blade holding portion 102 of the slider 6 in a stopped state with a single touch. Typically, the blade B is set so that the cutting edge BE (working portion) faces downwards, in order for the blade B to act on the workpiece from above. Also, for example, when the blade B acts on the workpiece from below, the blade B may be set so that the cutting edge BE faces upwards. The user adjusts the length of the guide shoe 16 as needed, and places the front surface of the guide shoe 16 against the workpiece. Furthermore, the user attaches a charged battery 54 to the battery attachment section 50. In addition, the user operates the speed switching dial 36 to select the speed. When the user holds the first grip portion 30 (and the second grip portion 60) and pulls the trigger 33 a predetermined amount, the main switch body portion 34 turns on, power is supplied to the motor 3, and the motor shaft 68 rotates. Power is supplied to the motor 3 from a DC power source rectified by the control circuit board 42. When the trigger 33 is pulled by more than a specific amount, the light 62 turns on. This specific amount is smaller than the predetermined amount at which power is supplied to the motor 3. The microcomputer of the control circuit board 42 acquires the rotation state of the rotor 67. Furthermore, the microcomputer of the control circuit board 42 controls the on / off of each switching element in accordance with the acquired rotation state, and causes a current to flow in sequence through each coil 66C of the stator 66, thereby rotating the rotor 67. The motor shaft 68 rotates at a rotation speed according to the signal (pulling amount of the trigger 33) of the turned-on main switch body 34. The rotation speed of the motor shaft 68 becomes faster as the pulling amount of the trigger 33 increases. In addition, the maximum rotation speed of the motor shaft 68 is controlled by the control circuit board 42 to a value according to the rotation state of the speed switching dial 36. When the motor shaft 68 rotates, the crank cam 78 rotates via the bevel gear 70, the torque limit mechanism 72, the intermediate shaft 74, and the crank base 76, and the slider 6 moves back and forth. Also, the balancer 170 moves in the opposite direction to the slider 6 in the front-rear direction, and the slider 6 moves back and forth in a state where vibration is suppressed.

[0073] The slider 6 is guided by the front and rear oilless bearings 181 in a state where it is prevented from facing in any direction other than the direction of the slider support body 180. When the user moves the knob portion 194 of the orbital switching lever 192 forward (see FIG. 1), the second flat surface 198 of the lever body 193 extends in all directions (see FIG. 3) and separates from the rear plate 182. The bearing 186 of the orbital mechanism 12 relatively follows the entire circumference of the cam surface 99 of the crank cam 78, and swings the slider support body 180 in accordance with the reciprocating motion of the slider 6. Thus, the orbital motion is performed by the entire reciprocating motion of the slider 6 (second orbital state). Also, when the user tilts the knob portion 194 of the orbital switching lever 192 backward, the first flat surface 196 of the lever body 193 extends forward, backward, left and right, and is ready to lift the rear plate 182. The bearing 186 of the orbital mechanism 12 relatively follows only about half the circumference of the cam surface 99 of the crank cam 78, oscillating the slider support body 180 in accordance with the reciprocating motion of the slider 6 only about half the circumference, and does not contact the cam portion 98 during the remaining about half the circumference, maintaining the position of the slider support body 180. Thus, the orbital motion is performed during about half of the reciprocating motion of the slider 6 (first orbital state).

[0074] When the user moves the blade B down toward the workpiece while the slider 6 or the blade B is in operation, the edge BE of the blade B moving back and forth comes into contact with the workpiece, and the workpiece is cut. The second orbital state is suitable, for example, for the workpiece being wood, and the first orbital state is suitable, for example, for the workpiece being metal.

[0075] Furthermore, the rotation of the fan 4 accompanying the rotation of the motor shaft 68 pushes the air around the fan 4 outward in the radial direction of the fan 4. Thus, an air flow (wind) is generated within the main housing 2, and various components within the main housing 2 are cooled. In particular, part of the wind passes between the upper part of the power transmission housing 20 and the upper part of the cover 22 to reach each vent hole 169, and further passes between the upper semicircular arc wall 167U and the wall 168, branching into a wind that flows directly downward and a wind that flows forward from the lower side of the upper semicircular arc wall 167U. The forward wind passes radially inward of the release drum main body 140M.

[0076] When the user operates the trigger 33 to turn off the main switch body 34, the motor shaft 68 of the motor 3 stops, and the various forward and backward movements and the wind stop. After a predetermined time has passed, the light 62 goes out.

[0077] When the user operates the operation piece 150 of the release drum 140 upward while the slider 6 is stopped, the protrusion 134 of the blade holding part 102 is moved in an arc via the inward protrusion 148. Thus, the blade B attached to the blade holding part 102 is removed by operating the operation piece 150.

[0078] The embodiments and modifications of the present invention are not limited to those described above. For example, the following modifications may be made to the embodiments and modifications of the present invention as appropriate. The orbital motion (trajectory motion) of the blade holding portion 102 etc. is not limited to an elliptical or semi-elliptical motion. For example, the orbital motion may be a reciprocating motion (swing motion) along a virtual semi-elliptical arc.

[0079] The cam portion 98 may be arc-shaped, straight, or curved when viewed from above. The cam portion 98 may be provided on the lower surface of the crank cam 78. The cam portion 98 may be a separate body from the crank cam 78. At least one of a part or the whole of the reciprocating motion conversion mechanism 5 and the orbital switching mechanism 14 (the orbital switching lever 192) may be disposed above the slider support 191. The reciprocating motion conversion mechanism 5 may be of a type that uses a crank and a connecting rod (connecting rod type) instead of a type that uses a crank cam 78 extending in all directions (horizontal crank type), or may be of a type that uses a rotating body with an inclined cylindrical surface and a swash bearing provided on the inclined cylindrical surface (swash type).

[0080] The cover 22 may be a half-piece having a left cover portion and a right cover portion. A needle bearing may be used instead of the ball bearing, or a ball bearing may be used instead of the needle bearing. At least one of the torque limit mechanism 72 and the intermediate shaft 74 may be omitted. The direction in which the battery 54 is attached and detached may be other than the front-rear direction. A plurality of batteries 54 may be attached. In addition, at least any of the presence or absence, number, material, shape, type, and arrangement of various members may be changed in various ways. The cutting tool may be something other than the blade B. Power may be supplied via a cord instead of the battery 54. The cord may be connected to a commercial power source. The embodiments and modifications of the present disclosure may be applied to reciprocating cutting tools other than the reciprocating saw 1 (for example, a jigsaw), and may also be applied to reciprocating tools other than reciprocating cutting tools, power tools, gardening tools, and power working machines. [Explanation of symbols]

[0081] 1··Reciprocating saw (reciprocating cutting tool), 3··Motor, 5··Reciprocating motion conversion mechanism, 6··Slider, 7··Release mechanism, 20··Power transmission housing, 102··Blade holding portion (tool holding portion), 140··Release drum (operation drum), 140F··Flange portion, 140G1, 140G2··Groove, 142··Tension spring (elastic body), 144A, 144B··Ring spring (ring member), 148··Inward protrusion, 150··Protrusion, 160U··First upper groove portion (first groove portion), 160D··First lower groove portion (first groove portion), 162U··Second upper groove portion (second groove portion), 162D ··Second lower groove portion (second groove portion), 164U··First upper cylindrical band portion (cylindrical band portion), 164D··First lower cylindrical band portion (cylindrical band portion), B··Blade (tip tool), BE··Blade (action part).

Claims

1. A motor; A rod-shaped slider; a reciprocating motion conversion mechanism that converts rotation of the motor into reciprocating motion in the forward / backward direction and transmits the reciprocating motion to the slider, the reciprocating motion conversion mechanism defining an extension direction of the slider as a forward / backward direction; a metallic power transmission housing that accommodates the reciprocating motion conversion mechanism; a tool holder that is detachably mounted on the slider and that is operable to attach and detach the tool; and a tool holder that is disposed at a front end of the slider; An operation drum made of synthetic resin that operates the operation of the tool holder by its own rotation; It is equipped with The operation drum is rotatably held within the power transmission housing via a metal ring spring that contacts the power transmission housing, The ring spring has a width of 4 mm or less, the ring spring is maintained in contact with the power transmission housing during rotation of the operating drum; The ring spring is disposed at least one of the front and rear of the outer surface of the operation drum. A reciprocating cutting tool characterized by:

2. A motor; A rod-shaped slider; a reciprocating motion conversion mechanism that converts rotation of the motor into reciprocating motion in the forward / backward direction and transmits the reciprocating motion to the slider, the reciprocating motion conversion mechanism defining an extension direction of the slider as a forward / backward direction; a metallic power transmission housing that accommodates the reciprocating motion conversion mechanism; a tool holder that is detachably mounted on the slider and that is operable to attach and detach the tool; and a tool holder that is disposed at a front end of the slider; An operation drum made of synthetic resin that operates the operation of the tool holder by its own rotation; It is equipped with The operation drum is rotatably held within the power transmission housing via one or more metal ring springs that contact the power transmission housing, the ring spring is maintained in contact with the power transmission housing during rotation of the operating drum; The ring spring is provided on at least one of the front and rear portions of the outer surface of the operation drum. A reciprocating cutting tool characterized by:

3. The ring spring is made of iron or an iron alloy.

3. A reciprocating cutting tool according to claim 1 or 2.

4. The power transmission housing is made of aluminum or an aluminum alloy.

4. A reciprocating cutting tool according to claim 1, wherein the cutting tool is a reciprocating cutting tool.

5. The operation of the tool bit holder is a removal operation, which is an operation of removing the tool bit.

5. A reciprocating cutting tool according to claim 1, wherein the cutting tool is a reciprocating cutting tool.

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