Patent ID: 12226841

DETAILED DESCRIPTION

Embodiments and modifications of the present disclosure will now be described with reference to the drawings as appropriate.

A reciprocating cutting tool according to one or more embodiments includes a power tool or a reciprocating tool, or more specifically, a reciprocating saw.

The directional terms such as front, rear, up, down, right, and left in the embodiments and the modifications are defined for ease of explanation, and may be changed depending on, for example, at least the operating situations or the status of a movable member.

The present disclosure is not limited to the embodiments and the modifications.

First Embodiment

FIG.1is a perspective view of a reciprocating saw1according to a first embodiment as viewed from the upper left front.FIG.2is a central longitudinal sectional view of the structure shown inFIG.1.FIG.3is a partial enlarged view ofFIG.2.FIG.4is a cross-sectional view taken along line A-A inFIG.3.

The reciprocating saw1includes a body housing2, a motor3, a fan4, a reciprocation converter5, a slider6as an output section, a guide shoe8, a counterweight9, an orbital unit12, an orbital switcher14, and a release unit201.

The body housing2is a support frame that directly or indirectly holds the components.

The body housing2includes a motor housing18, a power transmission housing20, and a cover22.

The motor housing18has a cylindrical front portion. The motor housing18has a looped rear portion. The motor housing18is formed from plastic.

The motor housing18holds the motor3in its upper front portion. The motor3includes a motor case3a. The motor case3adefines an outer wall of the motor3. The motor case3ais cylindrical. The motor case3ahas an open front portion. The motor housing18is connected to the power transmission housing20with the motor case3a.

The motor housing18is halved into a left motor housing18aand a right motor housing18b.

The left motor housing18ahas multiple screw bosses24. The right motor housing18bhas multiple screw holes (not shown). The screw holes are aligned with the screw bosses24. Multiple screws28are placed through the screw bosses24and the screw holes laterally, fastening the right motor housing18bto the left motor housing18a.

The looped rear portion of the motor housing18extends vertically and defines a first grip30. The first grip30is grippable by a user.

The motor housing18has multiple inlets31in the portion of the looped rear portion that faces the front surface of the first grip30. Each inlet31extends laterally. The inlets31are aligned vertically. The motor3is located in front of the inlets31.

The first grip30holds a main switch32in its upper portion.

The main switch32includes a trigger33and a main switch body34.

The trigger33is exposed at the upper front of the first grip30. The user pulls the trigger33with a fingertip to move the trigger33rearward. The trigger33is in front of the main switch body34. The trigger33is connected to the main switch body34.

The main switch body34is located in the upper portion of the first grip30. The main switch body34is turned on or off in response to an operation on the trigger33. The main switch body34is turned on when the pull of the trigger33reaches or exceeds a predetermined amount. The main switch body34outputs a signal (e.g., a resistance) that varies in accordance with the pull reaching or exceeding the predetermined amount.

The trigger33turns on or off the motor3through the main switch body34. The trigger33is a switch for turning on or off the motor3.

A lock-off button35is located above the trigger33. The lock-off button35is a laterally elongated plate.

The lock-off button35has its right and left portions exposed from the motor housing18. The lock-off button35is slidable rightward when the left portion is pressed. The lock-off button35is slidable leftward when the right portion is pressed.

The lock-off button35slid to a right position prevents the trigger33from being pulled. The motor3cannot be turned on in this state. The lock-off button35slid to a left position permits the trigger33to be pulled. The motor3can be turned on in this state.

A speed switching dial36is located in front of the lock-off button35. The speed switching dial36is a rotatable disk extending vertically and laterally. The speed switching dial36has its upper portion exposed from the motor housing18.

The speed switching dial36outputs a signal corresponding to its rotational position (angle).

The motor housing18holds a controller40below the motor3. The controller40includes a control circuit board42and a controller case44.

The control circuit board42controls the motor3. The control circuit board42includes a microcomputer and multiple (six or twelve) switching elements.

The controller case44is a metal (aluminum) box without a lid. The controller case44accommodates the control circuit board42. The control circuit board42is covered with a mold layer46of a material injected in the controller case44.

The controller40is located below the motor3. The controller40extends diagonally. More specifically, the controller40extends diagonally upward toward the front.

The controller case44has its front surface aligned with a front wall18W of a lower front portion18F of the motor housing18. The motor housing18holds the controller40.

The motor housing18has multiple lower rear outlets48in its lower front portion18F. Each lower rear outlets48extends laterally. The lower rear outlets48are aligned in the front-rear and lateral directions.

The lower rear outlets48are located downward from a portion holding the controller40in the motor housing18. More specifically, the lower rear outlets48are opposite to the fan4from the controller40in the motor housing18.

The space between the front surface of the controller case44and the front wall18W serves as an outlet passage allowing a cooling outlet blow WD to pass from the fan4. The outlet blow WD exits through the lower rear outlets48.

The motor housing18has a lower rear portion18E recessed upward from the lower front portion18F.

The lower rear portion18E receives a battery mount50.

The lower rear portion18E has an opening.

The battery mount50holds a terminal retainer52. The terminal retainer52has a box-like front portion. The terminal retainer52has a plate-like rear portion. The terminal retainer52covers the opening in the lower rear portion18E of the motor housing18. The terminal retainer52is exposed through the opening. The terminal retainer52holds multiple terminal plates (not shown).

The battery mount50receives a battery54that is slid forward from the rear. The mounted battery54is electrically connected to the terminal retainer52(terminal plates). The battery54powers the motor3.

The power transmission housing20supports the components of the reciprocation converter5, the slider6, the counterweight9, the orbital unit12, and the orbital switcher14directly or indirectly. The power transmission housing20is formed from metal. The power transmission housing20is connected to the front of the motor housing18.

The power transmission housing20is halved, and is a cylinder having openings in its front and rear ends. The power transmission housing20houses the reciprocation converter5. The power transmission housing20is thus also a converter housing.

The power transmission housing20includes an upper power transmission housing20a, a lower power transmission housing20b, and a bearing retainer114.

The upper power transmission housing20ais fastened to the lower power transmission housing20bwith multiple screws55(FIG.4) extending vertically.

The lower power transmission housing20bhas its rear end fastened to the front end of the motor housing18with multiple screws (not shown) extending in a front-rear direction from the motor case3a.

The cover22is cylindrical. The cover22is externally mounted on the power transmission housing20. The cover22is outward from the power transmission housing20. The cover22is elastic (rubbery). The cover22is located outside the power transmission housing20as a thermally or electrically insulating cover.

The cover22may not be a component of the body housing2. The cover22may be formed from plastic.

The rear end of the cover22covers the front end of the motor housing18. The cover22is continuous with the motor housing18on the outer surface.

The cover22has multiple body outlets56in the right and left portions in its middle portion (FIGS.1and9). Each left body outlet56extends in the front-rear direction. Each right body outlet56(FIG.9) extends in the front-rear direction. The multiple body outlets56are aligned vertically. The body outlets56are located frontward from the fan4.

The cover22has an orbital switching lever hole58in its left rear portion (FIG.1). The orbital switching lever hole58extends in the vertical and front-rear directions.

A lower portion of the cover22, or more specifically, a front portion of the body housing2, serves as a second grip60. The second grip60is grippable by a user.

At least the number of sections in the body housing2, the size of each section in the body housing2, or the shape of each section in the body housing2may be modified variously. For example, the rear portion of the motor housing18may be a separate handle housing. The battery mount50may be separate from the motor housing18.

A lamp62is located between the upper front portion of the power transmission housing20and the upper front portion of the cover22. The lamp62includes a light-emitting diode (LED) board. The LED board receives an LED.

The lamp62emits light forward. The lamp62can illuminate the area around the cutting position in front of the slider6.

The motor3, the main switch body34, the speed switching dial36, the terminal retainer52(terminal plates), and the lamp62each are electrically connected to the control circuit board42with multiple lead wires (not shown).

The portion of the motor housing18holding the motor3(the outside portion of the motor3), the power transmission housing20, the components held by these housings, and the cover22are included a body69of the reciprocating saw1.

The motor3is an electric motor. The motor3is a brushless motor. The motor3is driven with direct current (DC).

The motor3includes the motor case3a, a stator71, and a rotor72.

The motor case3ais held on the motor housing18.

The stator71includes multiple (six) coils73. The stator71is cylindrical.

A sensor board75is fixed to the stator71. The sensor board75receives multiple (three) magnetic sensors on its rear surface. Each magnetic sensor receives a rotation detection signal indicating the rotational position of the rotor72to obtain the rotational state of the rotor72. The sensor board75and the control circuit board42are electrically connected to each other with multiple (six) lead wires (signal lines, not shown). The signal lines extends through the lower front portion18F of the motor housing18.

A coil connector77is located at the stator71. The coil connector77serves as a contact for electrically connecting the coils73to one another in a predetermined manner. The coil connector77receives first ends of multiple (three) lead wires (power supply lines, not shown). The three power supply lines are used for three phases. Each power supply line extends through the lower front portion18F of the motor housing18. Each power supply line has a second end connected to the control circuit board42.

The rotor72is located inside the stator71. The motor3is an inner-rotor motor.

The rotor72includes a motor shaft80, a rotor core82, multiple (four) permanent magnets84, and a sleeve86.

The motor shaft80is cylindrical, and extends in the front-rear direction. The motor shaft80is formed from metal. The motor shaft80rotates on its axis. The motor shaft80has its front end extending into the rear end of the power transmission housing20. The motor shaft80receives a pinion gear80aon its front end. The pinion gear80aincludes multiple teeth.

The rotor core82is cylindrical. The rotor core82has an axis extending in the front-rear direction. The rotor core82includes multiple steel plates stacked on one another in the front-rear direction. Each steel plate extends in the vertical and lateral directions. The rotor core82is fixed on the outer surface of the motor shaft80.

Each permanent magnet84is a plate. The four permanent magnets84are circumferentially arranged in the rotor core82to alternate in polarity. The four permanent magnets84are not in contact with one another.

The sleeve86is a metal (brass) ring member. The sleeve86is fixed to the front of the rotor core82and the front of the permanent magnets84, and is fixed on the motor shaft80. The sleeve86fixed to the permanent magnets84can prevent the permanent magnets84from slipping off the motor shaft80.

A motor front bearing88is located in front of the sleeve86. The motor front bearing88surrounds the front portion of the motor shaft80. The motor front bearing88supports the motor shaft80in a manner rotatable on the axis.

The motor front bearing88is held on the rear portion of the lower power transmission housing20b.

A motor rear bearing92surrounds the rear end of the motor shaft80. The motor rear bearing92supports the motor shaft80in a manner rotatable on the axis. The motor rear bearing92is held on the motor case3a.

The fan4is located in the middle portion of the motor shaft80, behind the motor front bearing88, and in front of the sleeve86. The fan4is a centrifugal fan with multiple blades. The fan4rotates and forces air radially outward. The fan4is fixed to the motor shaft80integrally to rotate together. The fan4is located on the motor shaft80. The fan4is held on the motor housing18with the rotor72and the lower power transmission housing20b.

The lower power transmission housing20bis in front of the fan4.

The upper end of the air passage (lower air passage) defined between the front surface of the controller case44and the front wall18W of the lower front portion18F of the motor housing18is located below the fan4.

The fan4may be a component of the motor3.

FIGS.5and6each are a partially exploded perspective view of the reciprocation converter5and its surrounding components as viewed from above or below.FIG.7is a central longitudinal sectional view of part of the reciprocation converter5and its surrounding components.FIG.8is a central longitudinal sectional view of the part of the reciprocation converter5, with a knob174of an orbital switching lever170pressed forward (refer to the two-dot chain line inFIG.1) in the state inFIG.7.

The reciprocation converter5is a power transmission that transmits power from the motor3to the slider6. The reciprocation converter5transmits rotational motion of the motor shaft80of the motor3to the slider6. The reciprocation converter5is held on the power transmission housing20. The reciprocation converter5is located between the motor3and the slider6.

The reciprocation converter5includes a bevel gear100, a torque limiter102, a countershaft104, a crank base106, and a crank cam108.

The bevel gear100is a disk extending in the front-rear and lateral directions. The bevel gear100includes bevel teeth (not shown) on the periphery of its upper surface. The bevel gear100meshes with the pinion gear80a.

The bevel gear100rotates on a vertical rotation axis including its center in the front-rear and lateral directions.

The torque limiter102is located between the bevel gear100and the countershaft104.

The torque limiter102transmits power from the bevel gear100to the countershaft104. The torque limiter102includes upper and lower flat plates in close contact with each other under an urging force from an elastic member. In response to an excessive load from the countershaft104, the flat plates separate from each other against the urging force. This protects the bevel gear100and the motor3under the load.

The countershaft104is cylindrical and extends vertically.

The countershaft104is supported by an upper countershaft bearing110and a lower countershaft bearing112in a manner rotatable coaxially with the bevel gear100on the rotation axis (FIGS.2and3).

The upper countershaft bearing110is held on the lower power transmission housing20b.

The lower countershaft bearing112is a needle bearing. The lower countershaft bearing112is held in a dish-shaped bearing retainer114(FIGS.2and3). The bearing retainer114is fastened to the lower power transmission housing20bwith multiple screws116(one is shown inFIGS.2and3) extending vertically.

The crank base106is crank-shaped.

The crank base106includes a cylindrical part106A on the bottom. The cylindrical part106A is screwed to the upper portion of the countershaft104.

The crank base106includes a plate106B extending in the front-rear and lateral directions in the middle.

The crank base106includes an eccentric disk106C on its top. The center of the eccentric disk106C is off the central axis of the lower part of the crank base106. The eccentric disk106C extends in the front-rear and lateral directions.

The crank cam108includes a crank cam body120, an eccentric pin122, a convex roller124, and a bearing126.

The crank cam body120is a disk extending in the front-rear and lateral directions. The crank cam body120has a vertical central axis that is aligned with the rotation axis of the bevel gear100. The crank cam body120has a coupler127on its bottom. The coupler127is cylindrical and protrudes downward from the other portion. The coupler127receives the eccentric disk106C in the crank base106coupled with a screw128. The crank cam body120also includes a cam130on the periphery of the upper surface of the crank cam body120. The cam130protrudes upward from the adjacent portions. The cam130is annular as viewed from above. The cam130has a vertical length changing gradually in the circumferential direction (refer toFIGS.7and8, for example). In other words, the upper surface of the cam130serves as a cam surface130a. The cam surface130ahas a height that gradually changes from a lowest point130a1to a highest point130a2.

The eccentric pin122is cylindrical and extends vertically. The lower portion of the eccentric pin122is received in a vertical hole in the crank cam body120. The hole is radially off the central axis of the crank cam body120.

The convex roller124is cylindrical. The convex roller124has an outer surface with a diameter increasing toward its vertically middle portion.

The convex roller124surrounds the upper portion of the eccentric pin122with the bearing126between them. The convex roller124is supported in a manner rotatable on a vertical rotation axis. The bearing126is a needle bearing.

The slider6includes a slider body136and a blade holder138as a tip tool holder. The slider6has its front end protruding from the front end of the power transmission housing20.

The slider body136is cylindrical and extends in the front-rear direction. The slider body136has a convex roller receiver140in its rear portion. The convex roller receiver140is a bottomed elliptical cylinder extending laterally. The convex roller receiver140is open downward. The convex roller receiver140receives the convex roller124.

In response to rotation of the crank cam108, the convex roller124rotates eccentrically. The motion of the convex roller124includes a front-rear component that causes the slider body136to reciprocate in the front-rear direction through the convex roller receiver140. The lateral component of the motion of the convex roller124is its relative motion within the convex roller receiver140, and is not transmitted to the slider body136.

The blade holder138holds a blade (not shown) as a tip tool. The blade holder138automatically holds a blade in response to the rear end of the blade being simply inserted into the blade holder138(quick attachment).

The blade holder138is larger than the slider body136in the vertical and lateral directions. The slider6is an output section. The blade is a tip tool. The blade is an elongated plate and extends in the front-rear direction when attached. The blade has an edge on a longer side. The edge includes saw teeth. The blade is attached with its edge facing downward. The blade may be attached with its edge facing upward. The blade may have edges on the two longer sides. The tip tool may be any tool other than a blade.

The guide shoe8is located adjacent to the blade attached to the blade holder138.

The counterweight9is combined with the reciprocation converter5.

The counterweight9includes a metal balancer144and a ring145.

The balancer144is a plate extending in the front-rear and lateral directions. The balancer144has a long hole146extending laterally in the middle portion. The portion of the balancer144frontward from the long hole146is heavier than the portion rearward from the long hole146.

The long hole146receives the coupler127in the crank cam108with the ring145.

The portion of the balancer144frontward from the long hole146has a slit147extending in the front-rear direction. The slit147receives a pin148. The pin148extends vertically. The lower portion of the pin148is held on the lower power transmission housing20b.

The portion of the balancer144rearward from the long hole146has a recess149on its bottom. The recess149is recessed upward from the surrounding portion to avoid contact with the upper rear portion of the lower power transmission housing20b(refer toFIG.3).

The balancer144reciprocates in the front-rear direction as the crank cam108rotates. The coupler127is located opposite to the convex roller124from the center of the crank cam body120. More specifically, the coupler127and the convex roller124are at an angle of about 175° to each other about the center of the crank cam body120in the front-rear and lateral directions. The portion of the balancer144frontward from the long hole146thus basically moves opposite to the movement of the slider6in the front-rear direction. The balancer144thus reduces the vibrations generated by the reciprocation of the slider6. More specifically, the balancer144moves in the direction opposite to the backward and forward motion of the slider6, and thus serves as a counterweight. The lateral component in the motion of the coupler127is its relative motion within the long hole146, and is not transmitted to the balancer144. The angle between the coupler127and the convex roller124may be 180° or any other angle.

The orbital unit12includes a slider support body150, multiple (two) oilless bearings151as slider supports, multiple (two) plates152, a slider support shaft153, multiple springs154as elastic members, a bearing156, and multiple screws160.

The slider support body150, the oilless bearings151, the plates152, the bearing156, and the screws160are included in a cylindrical slider support161. The bearing156and other components may be eliminated from the components of the slider support161. At least one of the slider support shaft153or the springs154may be included in the components of the slider support161.

The slider support body150is a metal box extending in the front-rear direction.

The slider support body150holds the oilless bearings151on its front and rear portions. The oilless bearings151have a square cross section.

The slider6extends through the oilless bearings151in a reciprocable manner.

The slider support body150has an opening in its lower middle portion, where the convex roller124and the convex roller receiver140can be located. The oilless bearings151are located in front of and behind the opening.

A rear plate152is fastened to a lower rear portion of the slider support body150below a rear oilless bearing151with (two right and left) screws160extending vertically. The rear plate152is formed from metal, and extends in the front-rear and lateral directions. The slider support body150holds the rear oilless bearing151from above. The rear plate152holds the rear oilless bearing151from below.

A front plate152is fastened to a lower front portion of the slider support body150below a front oilless bearing151with (two, or right and left) screws160extending vertically. The front plate152is formed from metal, and extends in the front-rear and lateral directions. The slider support body150holds the front oilless bearing151from above. The front plate152holds the front oilless bearing151from below.

The plates152and the screws160may be eliminated.

The slider support body150has right and left shaft holes162extending laterally on its front bottom. The peripheries of the shaft holes162are fixed to the upper power transmission housing20a.

The slider support shaft153extends through the right and left shaft holes162. The slider support161is pivotable about the slider support shaft153.

The springs154are located on the right and left of the rear top of the slider support body150. The springs154extend vertically. The upper end of each spring154is held on the rear inner surface of the upper power transmission housing20a.

The bearing156is located behind the lower opening in the slider support body150and in front of the plate152. The bearing156is a ball bearing.

The inner ring of the bearing156is held on the outer surface of the oilless bearing151. The outer ring of the bearing156can be in contact with the cam130in the crank cam108.

The orbital switcher14includes an orbital switching lever170as an orbital switch. The orbital switching lever170includes a lever body172as a shaft and the knob174.

The lever body172is a rod-like shaft extending laterally.

The orbital switching lever170is held on the upper power transmission housing20ain a manner rotatable on a central axis C (refer toFIGS.7and8) of the lever body172. The central axis C of the lever body172is parallel to the plate152to be in contact with the lever body172.

The lever body172has a first flat surface176and a second flat surface178. The first flat surface176is a support flat surface extending laterally. The second flat surface178is a surface for a second orbital mode extending laterally. The first flat surface176and the second flat surface178are at a predetermined angle (about 100° in this example) to each other. The distance from the central axis C to the first flat surface176is larger than the distance from the central axis C to the second flat surface178.

In a first state of orbital (first orbital mode) as inFIG.7, the first flat surface176of the orbital switching lever170can be in contact with the rear bottom (rear plate152) of the slider support161. When the orbital switching lever170is in contact with the plate152, the first flat surface176extends, in the front-rear direction, on both sides of an imaginary perpendicular plane V (vertical plane, refer toFIG.7) including the central axis C and perpendicular to the first flat surface176. More specifically, the first flat surface176extends through the perpendicular plane V. In other words, the first flat surface176has a first portion176afrontward from the central axis C (perpendicular plane V) and a second portion176brearward from the central axis C (perpendicular plane V).FIG.4is a cross-sectional view taken along the perpendicular plane V.

In a second state of orbital (second orbital mode) as inFIG.8, the second flat surface178of the orbital switching lever170faces the rear bottom of the slider support161across a space. In this case, the bearing156in the orbital unit12comes in contact with the cam surface130aof the cam130throughout the circumference of the cam surface130a.

In the second orbital mode, the bearing156comes in contact with the lowest point130a1on the cam surface130a(refer toFIG.8) under the downward urging force from the springs154. The second flat surface178of the lever body172remains separate from the rear bottom of the slider support161in this state. This causes the slider support161, the slider6, and the blade to face upward (toward the front). The bearing156also comes in contact with the highest point130a2on the cam surface130a. The bearing156is then pushed upward by the cam surface130aagainst the urging force from the springs154, causing the slider support161, the slider6, and the blade to face downward (toward the front). The height of the portion of the cam surface130abetween the lowest point130a1and the highest point130a2in the circumferential direction changes gradually. Thus, rotation of the crank cam108moves the bearing156up and down as the bearing156travels relatively on the cam surface130a. The slider support161, the slider6, and the blade thus repeatedly face upward toward the front, align with the front-rear direction, face downward toward the front, and align in the front-rear direction. This causes an elliptical orbital action of the blade holder138.

The slider6is supported on the first portion176aand the second portion176bof the first flat surface176. The slider6supported on the surfaces thus restricts rotation of the lever body172on the central axis C upon an operation other than an operation on the knob174. This allows stable switching of the on-off state or the degree of orbital action with the lever body172having the first flat surface176and also simplifies the structure for switching the orbital action.

Orbital action is associated with the reciprocation of the slider6in accordance with the circumferential distribution of the height of the cam surface130ain the crank cam108. When moving forward, the slider6faces upward toward the front. When switching the moving direction from forward to backward (or passing near the switching point), the slider6aligns with the front-rear direction. When moving backward, the slider6faces downward toward the front. When switching the moving direction from backward to forward (or passing near the switching point), the slider6aligns with the front-rear direction. The height distribution of the cam surface130ais adjusted accordingly.

With the slider support161and the slider6facing either upward or downward, the convex roller124allows reciprocation of the slider6appropriately.

In the first orbital mode, the rear portion of the slider support161is lifted by the first flat surface176of the lever body172. The bearing156thus does not come in contact with the lowest point130a1and the adjacent portions on the cam surface130a. The slider6thus faces less upward toward the front than in the second orbital mode. In contrast, the bearing156comes in contact with the highest point130a2and the adjacent portions on the cam surface130a.

The bearing156comes in contact with the cam130on about half the cam130and does not come in contact with the cam130on the other half due to the first flat surface176of the lever body172. Thus, when moving backward, the slider6aligning with the front-rear direction faces downward toward the front, and then aligns again with the front-rear direction (or causes the semielliptical orbital action of the blade holder138) in the same manner as in the second orbital mode. However, when moving forward, the slider6remains mostly in alignment with the front-rear direction. In the first orbital mode, the blade holder138thus performs semielliptical orbital action.

In the first orbital mode, the blade holder138performs orbital action in a range of about half the rotation (first range). In the second orbital mode, the blade holder138performs orbital action throughout the rotation range (second range), which is wider than the range of about half the rotation (first range). Thus, the slider6is supported further stably on the first flat surface176in the first orbital mode in which the orbital action is performed in the first range.

In the first orbital mode, no orbital action may be performed throughout the rotation range. For example, elliptical orbital action may be performed on one-quarter of the rotation and may not be performed on the remaining three-quarters of the rotation. The range in which orbital action is performed (the on-off ratio of orbital action) may be changed in this manner.

Similarly, in the second orbital mode, orbital action may not be performed in a part of the rotation range. More specifically, the range in which orbital action is performed may be changed variously with the range of orbital action in the first orbital mode (first range) being smaller than the range of orbital action in the second orbital mode (second range).

The knob174crosses the lever body172. For example, the knob174crosses the lever body172orthogonally.

The knob174is located on the left of the power transmission housing20and the cover22. The knob174is exposed outside. The knob174is located in the orbital switching lever hole58in the cover22.

The user operates the knob174to rotate the orbital switching lever170on the central axis C to switch between the orbital modes.

FIG.9is a perspective view of a front portion of the reciprocating saw1as viewed from the upper right front.FIG.10is an enlarged partial view of a front portion inFIG.2.FIG.11is a cross-sectional view taken along line B-B inFIG.10.FIG.12is a cross-sectional view taken along line C-C inFIG.10.FIG.13is a partially exploded perspective view of an upper front portion of the reciprocating saw1as viewed from the above.FIG.14is a perspective view of a front portion of the upper power transmission housing20aas viewed from below. InFIG.9, the front plate of the guide shoe8is not shown.

A clearance is left between the left part of the power transmission housing20and the left part of the cover22to allow passage of a cooling outlet blow WL from the fan4. The outlet blow WL exits through the left body outlets56(FIG.1).

Similarly, a clearance is left between the right part of the power transmission housing20and the right part of the cover22to allow passage of a cooling outlet blow WR from the fan4. The outlet blow WR exits through the right body outlets56(FIG.9).

A ridge portion180is located on the top of the upper power transmission housing20a. The ridge portion180includes a pair of ridges extending in the front-rear direction. The ridge portion180includes a pair of walls protruding upward from the adjacent portions. The front end of the ridge portion180receives a housing180aof the lamp62. A lead wire connecting the lamp62to the control circuit board42extends through the ridge portion180. The ridge portion180houses the lead wire for the lamp62.

The upper end of the ridge portion180is in contact with the upper inner surface of the cover22. Clearances181L and181R, each as a first passage on the right or left of the ridge portion180, are left between the upper portion of the upper power transmission housing20aand the upper portion of the cover22. The clearances181L and181R allow passage of an outlet blow W1from the fan4. AlthoughFIGS.2,3, and10show the outlet blow W1overlapping the ridge portion180for ease of explanation, the outlet blow W1mostly flows through the clearances181L and181R.

The first passage for the outlet blow may not separate into right and left passages or may separate into three or more passage.

The upper power transmission housing20ahas a front wall184extending vertically and laterally in its front portion. The front wall184is in front of the slider support161. The front wall184has a hole receiving the slider body136through the front wall184.

The upper power transmission housing20ahas a wall186in front of the front wall184. The wall186protrudes from the upper inner surface of the upper power transmission housing20adownward from the adjacent portions. The wall186is a semicircular arc strip as viewed from rear and surrounds the slider6.

The upper power transmission housing20ahas a left hole188L and a right hole188R between the front wall184and the wall186. The left hole188L is on the left of the ridge portion180. The right hole188R is on the right of the ridge portion180.

The outlet blow W1passing through the clearance181L enters the left hole188L from above and flows forward until reaching in front of the left hole188L. Without the wall186, the outlet blow W1entering the left hole188L flows toward the blade holder138(refer to an outlet blow W2). Similarly, the outlet blow W1passing through the clearance181R enters the right hole188R from above and flows forward until reaching in front of the right hole188R. Without the wall186, the outlet blow W1entering the right hole188R flows toward the blade holder138.

In the reciprocating saw1, the wall186separates the outlet blow W1into the outlet blow W2and an outlet blow W3. The outlet blow W2flows toward the blade holder138. The outlet blow W3does not flow toward the blade holder138. More specifically, the clearances181L and181R, each as the first passage, branch into the second passage192and the third passage193between the front wall184and the wall186. The second passage192extends toward the blade holder138and extends frontward from the portion between the wall186and the slider6. The third passage193extend downward from the portion between the front wall184and the wall186.

The left hole188L and the right hole188R may not be separate right and left holes or may be separate three or more holes.

The lower power transmission housing20bincludes a lower wall196. The lower wall196is vertically symmetrical with the wall186. The lower wall196is a circular arc strip protruding upward from the lower inner surface of the lower power transmission housing20b. The upper end of the lower wall196is continuous and in contact with the lower end of the wall186.

The lower portion of the lower power transmission housing20bhas a lower front outlet198as a lower outlet (FIG.13) behind the lower wall196. The lower portion of the front wall184of the upper power transmission housing20ais located behind the lower front outlet198.

The space between the lower wall196and the slider6, together with the space between the wall186and the slider6, define the second passage192.

The space behind the lower wall196, together with the space between the front wall184and the wall186, defines the third passage193. The third passage193extends to the lower front outlet198. The outlet blow W3flows from the lower front outlet198through a clearance in the guide shoe8to the lower inner surface of the cover22. The outlet blow W3is then directed forward to exit through a portion below the blade holder138(around the base of the guide shoe8).

The release unit201is housed in the power transmission housing20in front of the wall186and the lower wall196.

The release unit201acts on the blade holder138for detachment of the blade.

The blade holder138in the slider6includes a push pin210, a push-pin compression spring211, a guide sleeve212, a holder pin213, a holder-pin compression spring214, an auxiliary pin215, a cam sleeve216, a stop ring217, an auxiliary sleeve218, and a torsion spring219.

The slider body136has, in its front end, a slit220, a first holder-pin hole222, a first auxiliary-pin hole223, and a step224.

The slit220extends in the front-rear and vertical directions. The slit220has a width (lateral dimension) slightly larger than the thickness of the blade.

The first holder-pin hole222is located on the left of the slit220and communicates with the slit220. The first holder-pin hole222extends laterally.

The first auxiliary-pin hole223is located on the right of the slit220and communicates with the slit220. The first auxiliary-pin hole223extends laterally. The first auxiliary-pin hole223faces the first holder-pin hole222. The first auxiliary-pin hole223receives, in the middle on its left inner surface, a rib protruding radially inward from the other portion.

The front end of the slider body136has an outer diameter smaller than the outer diameter of the rear portion of the slider body136. The step224is defined in the portion where the outer diameter of the slider body136changes.

The slit220receives the push pin210in its vertically middle portion. The push pin210extends in the front-rear direction. The push pin210has a D-shaped cross section.

The slit220receives the push-pin compression spring211in its vertically middle portion. The push-pin compression spring211is an elastic member, or more specifically, a coil spring. The push-pin compression spring211is located behind the push pin210. The rear end of the push-pin compression spring211is in contact with the torsion spring219. The front end of the push-pin compression spring211is in contact with the push pin210. The push-pin compression spring211is located between the push pin210and the slider body136. The push-pin compression spring211urges the push pin210frontward.

The guide sleeve212is cylindrical. The guide sleeve212is located outside the front end of the slider body136. The guide sleeve212has an axis extending in the front-rear direction.

The guide sleeve212has a second holder-pin hole226and a second auxiliary-pin hole228in its middle portion.

The second holder-pin hole226is located on the left of the guide sleeve212. The second holder-pin hole226extends laterally. The second holder-pin hole226is aligned with the first holder-pin hole222. The second holder-pin hole226has a larger diameter than the first holder-pin hole222.

The second auxiliary-pin hole228is located on the right of the guide sleeve212. The second auxiliary-pin hole228extends laterally. The second auxiliary-pin hole228faces the second holder-pin hole226. The second auxiliary-pin hole228has the same diameter as a portion of the first auxiliary-pin hole223leftward from the rib.

The holder pin213is received in the first holder-pin hole222and the second holder-pin hole226. The holder pin213is cylindrical and extends laterally. The holder pin213has its middle portion with substantially the same diameter as the left portion of the first holder-pin hole222. The holder pin213has a left end with a smaller diameter than the other portion. The holder pin213thus has a step on the left end (a stepped pin). The holder pin213has the left end tapered leftward. The holder pin213has a right end with a larger diameter than the other portion. The right end of the holder pin213is a head with a larger diameter than the other portion. The holder pin213has a curved right surface expanding rightward.

The holder-pin compression spring214is an elastic member, or more specifically, a coil spring. The holder-pin compression spring214has its left end in contact with the larger-diameter portion of the first holder-pin hole222. The holder-pin compression spring214has its right end in contact with the left surface of the head of the holder pin213. The holder-pin compression spring214is located between the holder pin213and the slider body136. The holder-pin compression spring214urges the holder pin213leftward.

The auxiliary pin215is received in the first auxiliary-pin hole223and the second auxiliary-pin hole228. The auxiliary pin215is cylindrical and extends laterally. The auxiliary pin215has its right end to be in contact with the rib on the first auxiliary-pin hole223. The auxiliary pin215has substantially the same diameter as the right portion of the first auxiliary-pin hole223and as the second auxiliary-pin hole228. The auxiliary pin215connects the guide sleeve212with the slider body136.

The cam sleeve216is cylindrical. The cam sleeve216has its axis extending in the front-rear direction. The cam sleeve216is located outside the guide sleeve212, the holder pin213, and the auxiliary pin215. The cam sleeve216is rotatable around the slider body136and the guide sleeve212.

The cam sleeve216has an extension in its top to left portions. The extension extends radially outward from the other portion of the cam sleeve216. The extension has a cam surface216C on its inner surface. The cam surface216C has a radial dimension gradually increasing counterclockwise from the top as viewed from the front. The cam surface216C is in contact with the curved surface of the head of the holder pin213.

Without the blade holder138receiving a blade, the head of the holder pin213is in contact with a portion of the cam surface216C nearer the largest radial dimension. With the blade holder138receiving a blade, the head of the holder pin213is in contact with a portion of the cam surface216C nearer the smallest radial dimension. The cam sleeve216includes a projection234protruding radially outward. The projection234is located on the right of the cam sleeve216.

The stop ring217is annular. The stop ring217is fixed on the outer surface of the guide sleeve212. The stop ring217is located in front of the cam sleeve216to restrict the forward movement of the cam sleeve216.

The auxiliary sleeve218is cylindrical. The auxiliary sleeve218has its axis extending in the front-rear direction. The auxiliary sleeve218is located outward from the slider body136and is rotatable about the slider body136. The auxiliary sleeve218is located in front of the step224. The step224restricts backward movement of the auxiliary sleeve218. The front end of the auxiliary sleeve218is received in the opening in the rear end of the cam sleeve216and connects to the rear end. The auxiliary sleeve218rotates together with the cam sleeve216.

The torsion spring219is annular and elastic. The torsion spring219has its rear end extending vertically in the middle in the lateral direction to be received in the slit220. The rear end of the torsion spring219is located between the rear bottom end of the slit220and the rear end of the push-pin compression spring211. The rear end of the torsion spring219is fixed to the slider body136. The torsion spring219excluding its rear end surrounds the front end of the slider body136and is located behind the auxiliary sleeve218. The torsion spring219has its front end received in a hole in the front-rear direction in the auxiliary sleeve218and fixed to the auxiliary sleeve218. The torsion spring219urges the auxiliary sleeve218circumferentially counterclockwise as viewed from the front.

The blade has a holding hole in its rear end. The holding hole has a slightly larger diameter than the right end of the holder pin213. The blade has a cutout in its corner opposite to the edge at the rear end of the blade. The blade has a protruding tab on its rear end protruding rearward on the same side as the edge. The blade has a shoulder at the upper rear of the protruding tab. The blade has a protrusion at its rear end.

Without the rear end of the blade received in the slit220, the front end of the push pin210is on the left of the holder pin213. The holder pin213retracts rightward.

With the rear end of the blade received in the slit220, the blade pushes, with the shoulder, the push pin210rearward against the urging force from the push-pin compression spring211.

When the rear end of the blade moves further rearward to cause the holding hole in the blade to reach the left of the holder pin213, the cam surface216C of the cam sleeve216pushes the holder pin213leftward against the urging force from the holder-pin compression spring214. More specifically, the cam sleeve216is urged by the torsion spring219through the auxiliary sleeve218. The torsion spring219applies an urging force counterclockwise as viewed from the front. In response to the holding hole in the blade reaching the left of the holder pin213to allow the holder pin213to move leftward, the cam sleeve216rotates counterclockwise as viewed from the front. The curved surface of the holder pin213comes in contact with an inward extending portion (a portion with a smaller diameter) of the cam surface216C. The cam surface216C pushes the holder pin213leftward.

When pushed leftward, a portion of the holder pin213leftward from the step enters the holding hole in the blade to hold the blade.

The blade is thus automatically held when simply inserted in the slit220(quick attachment).

The auxiliary pin215, which is different from the holder pin213, fixes the guide sleeve212to restrict its movement in the front-rear direction and its rotation relative to the slider body136. The holder pin213is received in the first holder-pin hole222having the right portion with the larger diameter.

The release unit201includes a release drum240and a tension spring242.

The release drum240is cylindrical and is housed in the power transmission housing20. The wall186restricts the backward movement of the release drum240. The release drum240is adjacent to the blade holder138. The release drum240surrounds the cam sleeve216. The release drum240is an operation drum operable by the user to detach (release) the blade from the blade holder138.

The release drum240includes an inward-raised portion248and an operation tab250.

The inward-raised portion248is located on the inner surface of the release drum240. The inward-raised portion248is raised radially inward from the other portion of the inner surface of the release drum240. The inward-raised portion248is located on the right of the release drum240.

The operation tab250is located on the right of the release drum240. The operation tab250protrudes radially outward from the other portion of the outer surface. The operation tab250extends from the upper left to the lower right as indicated by the solid line in the figure, and elongated in the front-rear direction. The operation tab250is integral with other parts of the release drum240(the cylindrical body of the release drum). The operation tab250protrudes rightward through a first operation tab hole252in the power transmission housing20and a second operation tab hole254in the cover22.

The tension spring242is a coil spring. The tension spring242is located circumferentially outside the release drum240and extends circumferentially on the release drum240. The tension spring242is housed in the power transmission housing20.

The tension spring242has a hook-shaped first end engaged with the release drum240. The tension spring242has a hook-shaped second end fixed to the lower power transmission housing20b.

With the tension spring242slightly stretched from its equilibrium length, the inward-raised portion248(the solid line inFIG.12) on the release drum240is not in contact with the projection234(dot-and-dash line inFIG.12) on the cam sleeve216in a blade holding state. In this state, the operation tab250on the release drum240is in contact with the lower ends of the first operation tab hole252and the second operation tab hole254. In this state, the tension spring242may be in other states, such as the state having the equilibrium length.

The user operates the operation tab250at the lower position upward to rotate the release drum240on its axis extending in the front-rear direction against the urging force from the tension spring242. This rotation of the release drum240causes the inward-raised portion248(the dot-and-dash line inFIG.12) to come in contact with the projection234on the cam sleeve216and rotate the cam sleeve216clockwise as viewed from the front. This places the head of the holder pin213inside the larger diameter portion on the cam surface216C. The holder pin213also retracts leftward and exits through the holding hole in the blade under the urging force from the holder-pin compression spring214(holding released). The push pin210then moves forward under the urging force from the push-pin compression spring211to push the released blade forward and then moves to the left of the holder pin213.

The release drum240in the release unit201cooperates with the internal blade holder138, causing the blade to be released from the blade holder138in response to the upward operation performed on the operation tab250.

The push pin210on the right of the holder pin213restricts rightward movement of the holder pin213. The holder pin213thus restricts counterclockwise rotation of the cam sleeve216as viewed from the front, against the urging force from the torsion spring219applied counterclockwise as viewed from the front.

The operation drum may be used to attach the blade instead of or in addition to releasing the blade.

The outlet blow W2toward the blade holder138flows between the release drum240and the slider6forward to the outside.

An operation example of the reciprocating saw1described above will now be described.

The user attaches a blade to the blade holder138in the slider6in an off-state. Typically, the blade is applied onto a workpiece from above. The blade is thus attached with the edge (applied part) facing downward. The blade may be attached to face upward to, for example, apply the blade from below.

The user adjusts the length of the guide shoe8as appropriate to place the front face of the guide shoe8onto a workpiece. The user attaches the charged battery54to the battery mount50. The user operates the speed switching dial36to select the speed.

The user then holds the first grip30(and the second grip60) and pulls the trigger33by a predetermined amount. This turns on the main switch body34and powers the motor3to rotate the motor shaft80. The motor3operates on DC power rectified through the controller40. The lamp62turns on in response to the trigger33pulled by an amount reaching or exceeding a specified amount. The specified amount is smaller than the predetermined amount set for the motor3to be powered.

A microcomputer in the controller40obtains information about the rotational state of the rotor72from the sensor board75. The microcomputer in the controller40also controls the on-off state of each switching element in accordance with the obtained information about the rotational state, and sequentially applies a current through the coils73in the stator71to rotate the rotor72. The controller40for the motor3, which is a brushless motor, may typically generate heat when, for example, driving the microcomputer. The heat accumulating on the controller40may affect the operation of the controller40.

The motor shaft80rotates at a rotational speed corresponding to a signal (the pulling amount of the trigger33) from the main switch body34in an on-state. The motor shaft80rotates at a higher rotational speed in correspondence with a larger pulling amount of the trigger33. The highest rotational speed of the motor shaft80is controlled by the controller40in accordance with the rotational state of the speed switching dial36.

In response to rotation of the motor shaft80, the crank cam108rotates with the bevel gear100, the torque limiter102, the countershaft104, and the crank base106, causing the slider6to move forward and backward. The balancer144moves in the direction opposite to the slider6in the front-rear direction. The slider6thus moves forward and backward with reduced vibrations.

The slider6guided by the front and rear oilless bearings151is restricted from facing in any direction other than the direction of the slider support body150.

When the user turns the knob174in the orbital switching lever170forward (refer to the two-dot chain line inFIG.1), the second flat surface178of the lever body172aligns with the front-rear and lateral directions (refer toFIG.8) and separates from the rear plate152. The bearing156in the orbital unit12travels relatively on the full circumference of the cam surface130aon the crank cam108, causing the slider support body150to pivot as the slider6reciprocates. This causes orbital action throughout the reciprocation of the slider6(second orbital mode).

When the user turns the knob174in the orbital switching lever170backward (refer to the solid line inFIG.1), the first flat surface176of the lever body172aligns with the front-rear and lateral directions (refer toFIG.7) and lifts the rear plate152. The bearing156in the orbital unit12travels relatively on about half the circumference of the cam surface130aon the crank cam108to cause the slider support body150to pivot with the reciprocation of the slider6for half the circumference. For the remaining half of the circumference, the bearing156does not come in contact with the cam130and retains the orientation of the slider support body150. This causes orbital action for about half the reciprocation of the slider6(first orbital mode).

As the user moves down the blade toward the workpiece with the slider6or the blade in operation, the edge of the blade reciprocating forward and backward comes in contact with the workpiece and cuts the workpiece.

The second orbital mode is suitable for a wood workpiece, for example. The first orbital mode is suitable for a metal workpiece, for example.

As the fan4rotates with rotation of the motor shaft80, the air around the fan4is forced radially outward. An airflow (blow) thus reaches the fan4through the inlets31after being through the motor housing18. The airflow then flows to the body outlets56and the lower outlet48. In other words, blows such as outlet blows WD, WL, WR, and W1to W3occur.

Such blows cool the components in the body housing2.

In particular, the motor3is cooled by the inlet blow through the inlets31to the fan4. The inlet blow cools the stator71and the rotor72by passing between the stator71and the rotor72. The inlet blow also passes through the stator71and cools the stator71.

The outlet blows WL and WR from the fan4to the body outlets56flows outside the power transmission housing20. The outlet blows WL and WR cool the power transmission housing20and the components inside.

The outlet blow WD from the fan4to the lower outlets48cools the controller40. The outlet blow WD flows near the controller case44covering the control circuit board42. The outlet blow WD thus cools the control circuit board42appropriately.

The outlet blow W1flows above the power transmission housing20. The outlet blow W2flows through the release drum240radially inward. The outlet blow W3flows in front of the power transmission housing20. The outlet blows W1to W3thus cool the power transmission housing20and the components inside and in front of the power transmission housing20. The outlet blow W1branches into the outlet blows W2and W3. This allows less outlet blow W2to flow toward the blade holder138than when the outlet blow W1does not branch. This reduces dispersion of dust produced from a workpiece. Although the outlet blow W3eventually flows forward, the outlet blow W3does not flows toward the blade holder138but flows forward around the guide shoe8below the blade holder138. This reduces dispersion of dust produced from a workpiece.

In response to the user turning off the main switch body34by operating the trigger33, the motor shaft80of the motor3stops to stop reciprocation motions and inflow and outflow of air. The lamp62turns off after a predetermined time.

The embodiments and the modifications are not limited to those described above. For example, the embodiments and the modifications may be further modified appropriately as described below.

Orbital action (trajectory motion) of the blade holder138and other components is not limited to elliptical and semi-elliptical motions. For example, the orbital action may include reciprocation along an imaginary semi-elliptical arc (swinging).

The first flat surface176may not be the continuous flat surface including the first portion176aand the second portion176b. For example, the first flat surface176may include a flat first portion176aand a flat second portion176bat a distance from the first portion176a. Such a first portion176aand a second portion176bmay together support the slider6directly or indirectly. At least one of the first portion176aor the second portion176bmay protrude from the surrounding portion.

The cam130may be arc-shaped, linear, or curved as viewed from above. The cam130may be located on the lower surface of the crank cam108. The cam130may be separate from the crank cam108.

At least one of a portion of the reciprocation converter5, the reciprocation converter5, or the orbital switcher14(orbital switching lever170) may be located above the slider support161.

The reciprocation converter5may include a crank and connecting rod (connecting rod type), in place of the crank cam108extending in the front-rear and lateral directions (horizontal crank type). In another example, the reciprocation converter5may include a rotational member with a sloping cylinder surface and swash bearings on the sloping cylinder surface (swash type).

The body outlets56may be located in a portion of the cover22frontward from the reciprocation converter5. The body outlets56may be located in the power transmission housing20. The lower outlets48may be located outside the controller40.

The cover22may be halved into right and left covers.

The ball bearing may be replaced by a needle bearing. The needle bearings may be replaced by ball bearings. At least one of the torque limiter102or the countershaft104may be eliminated. The size, arrangement, and number of at least the inlets31, the body outlets56, or the lower outlets48may be changed. The direction in which the battery54is attached or detached may be changed from the front-rear direction. Multiple batteries54may be attached. As described above, some of the components may be eliminated, or the number of components, their materials, shapes, types, and arrangement may be modified variously.

The tip tool may be any tool other than a blade.

In place of the battery54, a cord may be used to supply power. The cord may be connected to utility power.

The embodiments and their modifications are applicable to reciprocating cutting tools other than the reciprocating saw1(e.g., a jigsaw), as well as to reciprocating tools other than reciprocating cutting tools, power tools, gardening tools, and electric work machines.

Second Embodiment

FIG.15Ais a central longitudinal sectional view of a main portion of a reciprocating saw according to a second embodiment, with a highest point130a2on a cam surface130aat the rearmost position in a 1-1-orbital mode.FIG.15Bis a central longitudinal sectional view of the main portion of the reciprocating saw inFIG.15A, with a lowest point130a1on the cam surface130aat the rearmost position in the 1-1-orbital mode.

FIG.16Ais a central longitudinal sectional view of the main portion of the reciprocating saw inFIG.15A, with the highest point130a2on the cam surface130aat the rearmost position in a 1-2-orbital mode.FIG.16Bis a central longitudinal sectional view of the main portion of the reciprocating saw inFIG.16A, with the lowest point130a1on the cam surface130aat the rearmost position in the 1-2-orbital mode.

FIG.17Ais a central longitudinal sectional view of the main portion of the reciprocating saw inFIG.15A, with the highest point130a2on the cam surface130aat the rearmost position in the second orbital mode.FIG.17Bis a central longitudinal sectional view of the main portion of the reciprocating saw inFIG.17A, with the lowest point130a1on the cam surface130aat the rearmost position in the second orbital mode.

The reciprocating saw according to a second embodiment is the same as the reciprocating saw1according to the first embodiment except the lever body of the orbital switching lever (and the positional relationship with the cam surface130ain the vertical direction). The components and portions that are the same as those in the reciprocating saw1according to the first embodiment are given the same reference numerals, and will not be described.

A lever body272in an orbital switching lever270in the second embodiment has a first flat surface276, a second flat surface277, and a third surface278. The first flat surface276is a first support flat surface extending laterally. The second flat surface277is a second support flat surface extending laterally. The third surface278is a surface for the second orbital mode extending laterally.

The first flat surface276and the second flat surface277are at a predetermined angle (about 100° in this example) to each other. The second flat surface277and the third surface278are at a predetermined angle (about 100° in this example) to each other.

The distance from the central axis C to the first flat surface276is larger than the distance from the central axis C to the second flat surface277. The distance from the central axis C to the second flat surface277is larger than the distance from the central axis C to the third surface278.

In the 1-1-orbital mode inFIGS.15A and15B, the first flat surface276of the orbital switching lever270is constantly in contact with the rear bottom (rear plate152) of the slider support161.

In other words, when the highest point130a2on the cam surface130ais at the rearmost position as shown inFIG.15A, the first flat surface276supports the rear bottom of the slider support161, without the cam surface130abeing in contact with the slider support161(bearing156). When the lowest point130a1on the cam surface130ais at the rearmost position as shown inFIG.15B, the first flat surface276supports the rear bottom of the slider support161without the cam surface130abeing in contact with the slider support161. Thus, in the 1-1-orbital mode, no orbital action of the blade holder138is performed throughout the range of the reciprocation. The blade holder138reciprocates linearly forward and backward.

In this state, the first flat surface276extends, in the front-rear direction, on both sides of the imaginary perpendicular plane V including the central axis C and perpendicular to the first flat surface276. More specifically, the first flat surface276extends through the perpendicular plane V. In other words, the first flat surface276has a first portion276afrontward from the central axis C (perpendicular plane V) and a second portion276brearward from the central axis C (perpendicular plane V).

In the 1-2-orbital mode inFIGS.16A and16B, the second flat surface277of the orbital switching lever270can be in contact with the rear bottom of the slider support161.

In other words, when the highest point130a2on the cam surface130ais at the rearmost position as shown inFIG.16A, the cam surface130acomes in contact with the slider support161(bearing156), with the second flat surface277separating from the rear bottom of the slider support161. When the lowest point130a1on the cam surface130ais at the rearmost position as shown inFIG.16B, the second flat surface277supports the rear bottom of the slider support161, without the cam surface130abeing in contact with the slider support161. In the 1-2 orbital mode, in the same manner as in the first orbital mode, the orbital action of the blade holder138is not performed for about half the range of the reciprocation. The blade holder138reciprocates along a semi-elliptical trajectory.

In this state, the second flat surface277extends, in the front-rear direction, on both sides of the imaginary perpendicular plane V including the central axis C and perpendicular to the second flat surface277. More specifically, the second flat surface277extends through the perpendicular plane V. In other words, the second flat surface277has a first portion277afrontward from the central axis C (perpendicular plane V) and a second portion277brearward from the central axis C (perpendicular plane V).

In the second orbital state as inFIGS.17A and17B, the third surface278of the orbital switching lever270faces the rear bottom of the slider support161across a space.

In other words, when the highest point130a2on the cam surface130ais at the rearmost position as shown inFIG.17A, the cam surface130ais in contact with the slider support161(bearing156), with the third surface278being separate from the rear bottom of the slider support161. When the lowest point130a1on the cam surface130ais at the rearmost position as shown inFIG.17B, the cam surface130ais also in contact with the slider support161, with the third surface278being separate from the rear bottom of the slider support161. In other words, the bearing156in the slider support161comes in contact with the cam surface130athroughout the circumference. Thus, in the second orbital mode, the orbital action of the blade holder138is performed throughout the range of the reciprocation. The blade holder138reciprocates along an elliptical trajectory.

The diameter of the orbital switching lever170is smaller in the portion facing the screw160on the third surface278than in the other portion. The orbital switching lever170thus avoids contact with the screw160. The portion of the third surface278facing the screw160is recessed to avoid contact with the screw160.

The reciprocating saw according to the second embodiment can be modified as appropriate in the same manner as the reciprocating saw1according to the first embodiment.

The lever body272in the reciprocating saw according to the second embodiment may have three or more support flat surfaces.

Third Embodiment

FIG.18is a view of a reciprocating saw according to the third embodiment, similar toFIG.11.FIG.19is a view of the reciprocating saw according to the third embodiment, similar toFIG.14.

The reciprocating saw according to the third embodiment is the same as the reciprocating saw1according to the first embodiment except the structure of the wall and the lower wall in the power transmission housing and their surroundings, and the second passage192(outlet blow W2) being substantially eliminated. The components and portions that are the same as those in the reciprocating saw1according to the first embodiment are given the same reference numerals, and will not be described.

In the reciprocating saw according to the third embodiment, a wall386in an upper power transmission housing320aprotrudes more than the wall186in the first embodiment. Similarly, in the reciprocating saw according to the third embodiment, a lower wall396in a lower power transmission housing320bprotrudes more than the lower wall196in the first embodiment. At least one of the wall386or the lower wall396may protrude by a degree other than described above.

An elastic (rubber) ring397is located between the wall386and the lower wall396. The ring397extends vertically and laterally. The ring397has a groove397aon its circumference. The groove397ais recessed radially inward from its front and rear portions. The upper portion of the groove397areceives the wall386. The lower portion of the groove397areceives the lower wall396. The ring397is held by the wall386and the lower wall396. The ring397has a hole397bat its center.

The wall386, the lower wall396, and the ring397block the space from the front of the left hole188L and the right hole188R to the front of the lower front outlet198while allowing reciprocation the slider6. The slider body136is received in the hole397band in contact with the hole397b. The second passage192(outlet blow W2) toward the front (toward the blade holder138) is thus substantially eliminated in the third embodiment. The wall386, the lower wall396, the ring397, and the front wall184in the upper power transmission housing20abehind the ring397define a third passage393in the third embodiment. The third passage393extends outside the reciprocating saw without extending toward the blade holder138. The clearances181L and181R (first passage) connect to the third passage393alone. In the third passage393, the outlet blow W1from the left hole188L and the right hole188R does not branch and flows as the outlet blow W3without flowing toward the blade holder138.

In the third embodiment, the outlet blow W1flows above the power transmission housing20. Substantially no outlet blow W2flows through the release drum240radially inward. The outlet blow W3along the third passage393flows vertically in front of the power transmission housing20. The outlet blows W1and W3thus cool the power transmission housing20and the components inside. The outlet blow W1flows as the outlet blow W3without flowing toward the blade holder138. This allows less outlet blow W2to flow toward the blade holder138than when the outlet blow W1does not branch. This reduces dispersion of dust produced from a workpiece. Although the outlet blow W3eventually flows forward, the outlet blow W3does not flow toward the blade holder138but flows forward around the guide shoe8below the blade holder138. This reduces dispersion of dust produced from a workpiece.

The reciprocating saw according to the third embodiment may be modified as appropriate in the same manner as the reciprocating saw according to at least one of the first embodiment or the second embodiment.

REFERENCE SIGNS LIST

1reciprocating saw (reciprocating cutting tool)3motor4fan5reciprocation converter6slider12orbital unit14orbital switcher20power transmission housing20aupper power transmission housing20lower power transmission housing22cover30first grip (grip)62lamp71stator72rotor108crank cam (crank)122eccentric pin130cam138blade holder (tip tool holder)156bearing161slider support170,270orbital switching lever172,272lever body (shaft)176,276first flat surface (support flat surface)176a,276a,277afirst portion176b,276b,277bsecond portion178second flat surface (second orbital mode surface)180ridge portion181L,181R clearance (first passage)186wall188L,188R hole192second passage193third passage198lower front outlet (lower outlet)240release drum277second flat surface (support flat surface)278third surface (second orbital mode surface)C central axis (rotation axis) of the lever bodyW1outlet blow (for the first passage)W2outlet blow (for the second passage)W3outlet blow (for the third passage)