Reciprocating cutting tool

Abstract

The present invention provides a reciprocating cutting tool that allows for easy attachment and detachment of the blade, has a more compact outer diameter, and suppresses changes in the blade mounting angle. [Solution] The jigsaw, as a reciprocating cutting tool, is equipped with a blade holder 32 for attaching and detaching a blade 34, which is capable of reciprocating up and down. The blade holder 32 is movable in a direction approaching and moving away from the blade 34, i.e., in the left-right direction, and has a first pressing member 130 capable of pressing the blade 34, a first biasing member 134 that biases the first pressing member 130, a second pressing member 142 capable of pressing the blade 34 in a direction different from the direction of pressing by the first pressing member 130, i.e., downward, and a second biasing member 144 that biases the second pressing member 142. When the second pressing member 142 is pressed by the blade 34, the first pressing member 130 automatically presses the blade 34. The first biasing member 134 is positioned to avoid the direction of movement of the first pressing member 130.

Description

Technical Field

[0001] The present invention relates to reciprocating cutting tools such as jigsaws and reciprocating saws.

Background Art

[0002] A jigsaw disclosed in Japanese Patent Application Laid-Open No. 2002-254403 (Patent Document 1) is known. This jigsaw 10 includes a clamp device 26 for a blade 22. The clamp device 26 switches the blade 22 between an unlocked state and a locked state as a sleeve 33 rotates. The sleeve 33 is urged in the rotational direction by a coil spring 44. In the locked state, the clamp device 26 sandwiches the blade 22 between a pin 42 pushed by a cam 33c of the sleeve 33 and a wall surface 37j of a slit 37a of a rod 37. The coil spring 44 is disposed radially outside the diameter of the pin 42 that presses the blade 22. When the user attaches and detaches the blade 22, it is necessary to handle the blade 22 while maintaining the unlocked state by holding the rotational position of the sleeve 33 while maintaining an open operation on the operation member 52.

[0003] Also, a blade attachment device for a jigsaw disclosed in Japanese Patent Application Laid-Open No. 2011-255449 (Patent Document 2) is known. This blade attachment device 10 includes a rod 11, a blade guide 12 having a cylindrical shape and held via a cylindrical guide support member 15 at the lower end of the rod 11, a cylindrical guide engagement member 20 disposed below the guide support member 15, blade holders 13 and operation members 1 each having a cylindrical shape and assembled to each other in a state of accommodating the guide support member 15 and the guide engagement member 20 on the inner peripheral side, and a torsion spring 18 interposed between the operation member 14 and the guide engagement member 20 and biasing the operation member 14 in the rotational direction toward the blade attachment position. The blade guide 12 is housed in the inner circumference hole of the rod 11 so as to be movable in the axial direction, and is pushed inward by the pushing operation of the blade B received in its guide groove 12c. Then, a pair of anti-rotation edges 12a of the blade guide 12 are withdrawn from the corresponding engagement grooves 13f of the blade holder 13, and the operating member 14 automatically rotates toward the blade mounting position due to the biasing force of the torsion spring 18. The blade B has a pair of engagement lugs Bb. The engagement lugs Bb are sandwiched from above and below by the corresponding stopper grooves 20a of the guide engagement member 20 and the corresponding cam portion 13e of the blade holder 13 which has rotated toward the blade mounting position. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2002-254403 [Patent Document 2] Japanese Patent Publication No. 2011-255449 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In the clamping device 26 described above, the coil spring 44 is positioned radially outward of the pin 42 that presses the blade 22. As a result, the clamping device 26 has a larger diameter. Consequently, the user has difficulty seeing the area around the blade 22 during operation due to the increased diameter. Furthermore, with the clamping device 26, it is necessary to maintain the open position relative to the operating member 52 when attaching or detaching the blade 22, which is time-consuming. Furthermore, in the blade mounting device 10 described above, each engaging tab Bb of the blade B is sandwiched from above and below. Therefore, each engaging tab Bb is prone to wear. When each engaging tab Bb wears down, the mounting angle of the blade B changes, which affects workability. [Means for solving the problem]

[0006] This specification discloses a reciprocating cutting tool. The reciprocating cutting tool may include a reciprocating blade attachment / detachment unit for attaching and detaching a blade. The blade attachment / detachment unit may include a first pressing member that is movable toward and toward the blade and capable of pressing the blade. The blade attachment / detachment unit may include a first biasing member that biases the first pressing member. The blade attachment / detachment unit may include a second pressing member that is capable of pressing the blade in a direction different from the direction of pressing by the first pressing member. The blade attachment / detachment unit may include a second biasing member that biases the second pressing member. When the second pressing member is pressed by the blade, the first pressing member may automatically press the blade. The first biasing member may be positioned to avoid the direction of movement of the first pressing member.

[0007] Furthermore, this specification discloses another embodiment of a reciprocating cutting tool. This reciprocating cutting tool may include a reciprocating blade attachment / detachment section for attaching and detaching a blade. The blade attachment / detachment section may include a first pressing member that is movable in a direction toward and toward the blade and capable of pressing the blade. The blade attachment / detachment section may include a first biasing member that biases the first pressing member. The blade attachment / detachment section may include a second pressing member that is capable of pressing the blade in a direction different from the direction of pressing by the first pressing member. The blade attachment / detachment section may include a second biasing member that biases the second pressing member. The blade attachment / detachment section may include a sleeve that is rotatable about the direction of reciprocating motion. The first pressing member and the first biasing member may be arranged radially inward of the sleeve. The first pressing member may move in accordance with the rotation of the sleeve. The second pressing member may extend in the direction of reciprocating motion. The second pressing member may have an engaging portion, a pressing portion, and a tongue portion. The sleeve may have an engaged portion. The rotation of the sleeve may be stopped by the engaging portion with the engaged portion. The tongue portion may integrally connect the engaging portion and the pressing portion. When the pressing portion is pressed by the blade, the engaging portion may move and disengage from the engaged portion. The tongue portion and the pressing portion may extend in the direction of reciprocating motion. The virtual center line of the tongue portion may be offset in a direction perpendicular to the direction of reciprocating motion with respect to the virtual center line of the pressing portion. [Effects of the Invention]

[0008] The reciprocating cutting tool of this disclosure allows for easy attachment and detachment of the blade. Furthermore, the reciprocating cutting tool of this disclosure has a more compact outer diameter. Moreover, the reciprocating cutting tool of this disclosure suppresses changes in the mounting angle of the blade. [Brief explanation of the drawing]

[0009] [Figure 1] These are perspective views of the front, top, and left side of a jigsaw according to an embodiment of the present disclosure. [Figure 2] This is a central longitudinal section of the jigsaw in Figure 1. [Figure 3] This is a cross-sectional view along line AA in Figure 2. [Figure 4] Figure 1 shows exploded perspective views of the blade, blade holder, and slider body of the jigsaw, including the top, front, and left sides. [Figure 5] Figure 1 shows exploded perspective views of the blade, blade holder, and slider body of the jigsaw, including the bottom, rear, and right sides. [Figure 6] Figure 4 is a perspective view of the rear half of the sleeve in the blade holder when the blade is locked. [Figure 7] Figure 7A is a bottom view of the blade holder before blade insertion, and Figure 7B is a bottom view of the blade holder when the blade is locked. [Figure 8] Figure 8A is a cross-sectional view of the blade holder portion along line AA before and during blade insertion, and Figure 8B is a cross-sectional view of Figure 8A along line CC. [Figure 9] Figure 9A is a cross-sectional view of the blade holder portion along line AA when the blade is pushed in, and Figure 9B is a cross-sectional view of Figure 9A along line DD. [Figure 10] Figure 10A is a cross-sectional view of the blade holder portion along line AA when the blade is locked, and Figure 10B is a cross-sectional view of Figure 10A along line EE. [Figure 11]Figure 11A is a cross-sectional view along the FF line in Figure 8B, Figure 11B is a cross-sectional view along the GG line in Figure 9B, and Figure 11C is a cross-sectional view along the HH line in Figure 10B. [Modes for carrying out the invention]

[0010] In one embodiment of the present disclosure, the second pressing member may be movable in the direction of reciprocating motion. The direction of movement of the first pressing member may be perpendicular to the direction of movement of the second pressing member. The first biasing member may be positioned offset from the first pressing member in the direction of reciprocating motion. In this case, the radial size of the blade attachment / detachment portion is suppressed. In one embodiment of this disclosure, the first biasing member may be a torsion spring. The second pressing member may be arranged radially inward of the first biasing member. In this case, the space within the blade attachment / detachment section is effectively utilized. As a result, the blade attachment / detachment section becomes more compact.

[0011] In one embodiment of this disclosure, the blade attachment / detachment section may include a sleeve. The sleeve may be rotatable around the direction of reciprocating motion. The first pressing member and the first biasing member may be arranged radially inward of the sleeve. In this case, the internal space of the sleeve is effectively utilized. Thus, the blade attachment / detachment section becomes more compact. In one embodiment of the present disclosure, the sleeve may have a cam surface on its inner surface. The first pressing member may move in accordance with the rotation of the sleeve by following the cam surface. In this case, the compactness of the blade attachment / detachment section is maintained while the sleeve allows the first pressing member to move for pressing the blade. In one embodiment of this disclosure, the second pressing member may extend in the direction of reciprocating motion. The second pressing member may have an engaging portion. The sleeve may have an engaged portion. The rotation of the sleeve may be stopped by the engaging portion of the engaging portion. In this case, the rotation of the sleeve can be stopped while maintaining the compactness of the blade attachment / detachment portion. In one embodiment of the present disclosure, when the engaging portion engages with the engaged portion, the sleeve may be capable of moving the first pressing member to a position where it does not press the blade. When the engagement of the engaging portion with the engaged portion is released, the sleeve may move the first pressing member to a position where it presses the blade. In this case, the compactness of the blade attachment / detachment portion is maintained, and the pressing for locking the blade is reasonably performed.

[0012] In one embodiment of the present disclosure, the second pressing member may have a pressing portion and a tongue portion. The tongue portion may integrally connect the engaging portion and the pressing portion. When the pressing portion is pushed by the blade, the engaging portion may move and disengage from the engaged portion. In this case, in the second pressing member, the pressing portion that presses the blade and the engaging portion for controlling the rotation of the sleeve are integrated, and the structure of the second pressing member becomes simpler while having sufficient functions. In one embodiment of the present disclosure, the tongue portion and the pressing portion may extend in the direction of reciprocating motion. The virtual center line of the tongue portion may be offset in a direction orthogonal to the direction of reciprocating motion with respect to the virtual center line of the pressing portion. In this case, the compactness of the blade attachment / detachment portion is maintained, and the engagement of the engaging portion of the second pressing member with the engaged portion for controlling the rotation of the sleeve and its release are more sufficiently performed.

[0013] In one embodiment of the present disclosure, the virtual center line in the extending direction of the blade attached to the blade attachment / detachment portion may be offset toward the first pressing member side in a direction orthogonal to the direction of reciprocating motion with respect to the virtual center line in the extending direction of the blade attachment / detachment portion. In this case, the blade attachment / detachment portion can correspond to various thicknesses of the blade.

Example

[0014] Hereinafter, the embodiments of the present disclosure will be described as appropriate based on the drawings. The description includes modifications of the embodiments. The present disclosure is not limited to the embodiments and the modifications. The front, back, top, bottom, left, and right directions in the above configuration and modification examples are defined for explanatory purposes only and may change depending on the work situation and the movement of components, among other factors.

[0015] Figure 1 is a perspective view of the front, bottom, and left side of a jigsaw 1, which is an example of a reciprocating cutting tool according to an embodiment of the present disclosure. Figure 2 is a central longitudinal cross-sectional view of the jigsaw 1. Figure 3 is a cross-sectional view taken along line AA in Figure 2. The jigsaw 1 comprises a main body 2, a base 6, and a rechargeable battery 8. The jigsaw 1 is rechargeable and powered by the battery 8. The battery 8 is for power tools. The battery 8 may also be treated as a component of the main body 2. Alternatively, the battery 8 may be a component independent of the jigsaw 1. Furthermore, the battery 8 may be a primary battery. Also, the battery 8 does not have to be for power tools; for example, it may be a general-purpose battery. Furthermore, instead of the battery 8, a power cord connected to a power source may be used. A jigsaw with a power cord connected to an AC power source is an AC type. In Figure 2, the right side represents the front of Jigsaw 1. Also, in Figure 2, the top represents the top of Jigsaw 1. Note that Figures 1 through 3 show the blade locked.

[0016] The main body section 2, when viewed from left to right, is "L" shaped overall. The front part of the main body section 2F extends vertically. The rear part of the main body section 2B extends backward from the lower rear side of the front part of the main body section 2F. The rear part of the main body section 2B is barrel-shaped. The main body 2 includes a housing 10, an electric motor 12, a fan 14, a rear bearing 15, a front bearing 16, a battery mounting section 18, a controller 20, a speed adjustment switch 22, a main body connector 24, a switch unit 25, multiple (two) ON / OFF switches 26, multiple (two) lock-off switches 27, a power transmission section 28, a slider 29 as an output section, a slider guide 30, a dust seal 31, a blade holder 32 as a blade attachment / detachment section, a blade 34 as a tip tool, a tool opener 35, an orbital motion section 36, an orbital switching section 37, a counterweight section 38, and a guard 39. Inside the main body 2, generally from rear to front, the following components are arranged: battery mounting section 18, controller 20, main body connector 24, rear bearing 15, electric motor 12, fan 14, front bearing 16, power transmission section 28, orbital motion section 36, counterweight section 38, slider 29, blade holder 32, switch unit 25, guard 39, and tool opener 35. Furthermore, the arrangement of various components and parts can be changed in various ways. Also, the blade 34 may not be a component of the main body 2 or the jigsaw 1, but may be a component independent of the main body 2 or the jigsaw 1. In addition, the slider 29 may be a component of the power transmission unit 28, and the blade holder 32 may be treated as an output unit. Furthermore, the slider 29 and the blade holder 32 may together be treated as an output unit. In addition, a handle that forms a loop when combined with the main body 2 may be provided.

[0017] The housing 10 forms the outer casing of the main body 2. The housing 10 directly or indirectly holds various components. The housing 10 comprises a main housing 40 and a gear housing 42.

[0018] The main housing 40 is made of plastic. The main housing 40 is split in half and has a left main housing 40L and a right main housing 40R. The left main housing 40L has multiple screw boss portions 40B. The right main housing 40R has a screw hole portion. The screw hole portion has screw holes corresponding to the screw boss portions 40B. The left main housing 40L and the right main housing 40R are joined together by screws 43 that go into the screw hole portions and the screw boss portions 40B. The main housing 40 is L-shaped when viewed from right to left. The upper part of the main housing 40 is grippable by the user. A rear lower opening is formed at the rear lower part of the main housing 40. Furthermore, a front lower opening is formed at the front lower part of the main housing 40. The main housing 40 has a plurality of intake ports 44 and a plurality of exhaust ports 47. Each air intake port 44 extends in the front-to-back direction. Some of the air intake ports 44 are arranged vertically in the central part of the left main housing 40L in the front-to-back direction. Other air intake ports 44 are arranged vertically in the central part of the right main housing 40R in the front-to-back direction. Each exhaust port 47 extends forward and backward. Some exhaust ports 47 are located at the top of the left main housing 40L. Other exhaust ports 47 are located at the top of the right main housing 40R. The negative pressure generated by the rotation of the fan 14 draws air in through each intake port 44, which cools the electric motor 12. Most of the air that has cooled the electric motor 12 is then blown out between the bifurcated sections of the base 110. The remaining air that has cooled the electric motor 12 is then discharged through each exhaust port 47.

[0019] The gear housing 42 is made of aluminum die-cast alloy. The gear housing 42 is a bell-shaped member with an opening at its lower end. The gear housing 42 is split in half and has a front gear housing 42F and a rear gear housing 42B. The front gear housing 42F has screw holes in its upper right, lower right, and upper left sections. The rear gear housing 42B has screw bosses corresponding to the screw holes. The front gear housing 42F and the rear gear housing 42B are joined together by screws that fit into the screw holes and screw bosses. The gear housing 42 is held in place by the main housing 40. The gear housing 42 directly or indirectly holds the power transmission unit 28, the orbital motion unit 36, the counterweight unit 38, the slider 29, and the blade holder 32. The rear lower part of the gear housing 42 is exposed downward through the front lower opening of the main housing 40. The rear surface of the gear housing 42 has an upper hole, an upper opening, and a middle opening.

[0020] Furthermore, the housing 10 can be modified in various ways. For example, in the main housing 40, the outer casing of the front part 2F of the main body and the outer casing of the rear part 2B of the main body may be separate parts that can be combined with each other. Also, in the split main housing 40, the size and shape of at least one of the left main housing 40L and the right main housing 40R may be significantly different. Moreover, the left main housing 40L and the right main housing 40R may be combined using locking parts such as claws and locking parts such as claw holes, rather than by screws. The gear housing 42 may be a single unit without being separated into front and rear parts. The main housing 40 and the gear housing 42 may be a single unit. At least one of the materials of the various parts of the housing 10, as well as the number and arrangement of openings, may be changed. Also, at least one of the number and arrangement of exhaust ports 47 may be changed as appropriate.

[0021] The electric motor 12 is a brushless motor and a DC motor. The electric motor 12 is held in the main housing 40. The main housing 40 can be considered a motor housing because it holds the electric motor 12. The electric motor 12 has a stator 51 and a rotor 52. The stator 51 is cylindrical and held in the main housing 40 with a virtual central axis extending in the front-to-back direction. The rotor 52 has a motor shaft 53 that extends in the front-rear direction. The rotor 52 is cylindrical with the motor shaft 53 passing through its center, and is positioned radially inward of the stator 51. The rotor 52 rotates around the motor shaft 53. A pinion section 54 is formed at the front end of the motor shaft 53.

[0022] The fan 14 is fixed integrally with the motor shaft 53. Fan 14 is a centrifugal fan. However, other types of fans, such as axial fans, may be used instead of fan 14. The rear of the lower opening of the main housing 40 is located radially outward from the fan 14.

[0023] The rear bearing 15 is a ball bearing. The rear bearing 15 rotatably supports the motor shaft 53. The rear bearing 15 is located between the electric motor 12 and the controller 20. The outer ring of the rear bearing 15 is held in the main housing 40. The front bearing 16 is a ball bearing. The front bearing 16 rotatably supports the motor shaft 53. The front bearing 16 is positioned between the fan 14 and the pinion section 54. The front bearing 16 is positioned on the front side of the fan 14. The outer ring of the front bearing 16 is held in the central opening of the gear housing 42. Furthermore, at least one of the rear bearing 15 and the front bearing 16 may be of another type. For example, the rear bearing 15 may be a needle bearing. Other types of bearings can also be similarly modified.

[0024] The battery mounting section 18 is located at the rear end of the main body section 2. The battery 8 is installed in the battery mounting section 18. The battery mounting section 18 has terminals on the main body side that are connected to the terminals of the battery 8. The terminals on the main body side are located in the rear lower opening of the main housing 40. The battery 8 is installed on the underside of the battery mounting section 18. The battery 8 is installed by sliding it from the rear to the front of the battery mounting section 18 with the terminals of the battery 8 facing upwards. However, the direction in which the battery 8 is slid into place may be other than from rear to front. Furthermore, the battery 8 may be installed in a manner other than sliding it in. Battery 8 is a 36V lithium-ion battery. Battery 8 contains eight cells (not shown) within a plastic battery case. The cells are axially elongated cylindrical and extend to the left and right when Battery 8 is installed. Battery 8 holds the power to drive the electric motor 12. Note that any lithium-ion battery with voltages such as 10.8V, 14.4V, 18V, 25.2V, or 28V may be used as Battery 8. Alternatively, a lithium-ion battery with a voltage below 10.8V or above 36V may be used as Battery 8. Other types of batteries may be used as Battery 8. Multiple batteries 8 may be used.

[0025] The controller 20 is held above the battery mounting section 18. The controller 20 controls the electric motor 12. The electric motor 12 is electrically connected to the controller 20. The main body side terminals of the battery mounting section 18 are electrically connected to the electric motor 12 via the main body connector 24. Furthermore, the controller 20 is electrically connected to a speed adjustment switch 22, a switch unit 25, an ON / OFF switch 26, and a lock-off switch 27.

[0026] The speed adjustment switch 22 is a dial-type switch. The speed adjustment switch 22 has a disc portion that extends forward, backward, left, and right. The disc portion of the speed adjustment switch 22 is rotatable around a virtual central axis that extends vertically. The left portion of the disc portion of the speed adjustment switch 22 is exposed through a hole formed on the left side of the main housing 40. The user rotates the disc portion by moving the left portion of the disc portion forward or backward. The speed adjustment switch 22 outputs a signal corresponding to the amount of rotation of the disc portion. The output signal is sent to the controller 20. The speed adjustment switch 22 may be omitted.

[0027] The main unit connector 24 is interposed in a lead wire (not shown) that connects the controller 20 to the main unit terminal of the battery mounting section 18. The main unit connector 24 can be detached so that it can be reconnected. If the electric motor 12 needs to be replaced due to a malfunction or other reason, it can be easily replaced by detaching the main unit connector 24. In this case, the controller 20 connected to the electric motor 12 can also be replaced at the same time. The main unit connector 24 may be omitted.

[0028] The switch unit 25 is located above the guard 39 in the main body 2. The switch unit 25 is held in the housing 10. The switch unit 25 has a light (not shown). The light is an LED. The light illuminates the workpiece being processed by the blade 34 and its surroundings. The light turns on and off in accordance with the switching of the lock-off switch 27. When the lock-off switch 27 is turned on, the light turns on. When the ON / OFF switch 26 is turned off, the light turns off after a predetermined time. When the lock-off switch 27 is turned off, the light turns off immediately. The lights are controlled by the controller 20. The switch unit 25 is connected to the controller 20 by lead wires (not shown). The light may be omitted. The light may be a separate unit from the switch unit 25. Also, the way the light is turned on and off is not limited to those described above. For example, the light may be turned on and off by a dedicated light switch.

[0029] Each ON / OFF switch 26 is a tact switch. The left ON / OFF switch 26 is held in the front left part of the main housing 40. The right ON / OFF switch 26 is held in the front right part of the main housing 40. The ON / OFF switch 26 alternately sends an ON signal or an OFF signal to the controller 20 each time it is pressed by the user.

[0030] Each lock-off switch 27 is a tact switch. The left lock-off switch 27 is located on the left front of the main housing 40, above the ON / OFF switch 26. The right lock-off switch 27 is located on the right front of the main housing 40, above the ON / OFF switch 26. The lock-off switch 27 alternately sends an ON signal or an OFF signal to the controller 20 each time it receives a press operation from the user. Furthermore, the type of at least one of the ON / OFF switch 26 and the lock-off switch 27 can be changed in various ways. For example, the ON / OFF switch 26 may be a toggle switch instead of a tact switch. The types of the other switches can also be changed in various ways in a similar manner.

[0031] When the controller 20 receives an ON signal from the lock-off switch 27, it activates a timer to determine the elapsed time. After receiving the ON signal, if the controller 20 receives an ON signal from the ON / OFF switch 26 before the predetermined time has elapsed, it turns on the power to the jigsaw 1 and drives the electric motor 12. The controller 20 controls the rotation speed of the electric motor 12 based on a signal from the speed adjustment switch 22 corresponding to the amount of rotation of the disc. On the other hand, when the power to the jigsaw 1 is on, the controller 20 receives an off signal from the ON / OFF switch 26 and turns off the power to the jigsaw 1, stopping the electric motor 12. When the power is on, turning off the lock-off switch 27 stops the electric motor 12 and turns off the light. Furthermore, the control of the power supply and other functions of the jigsaw 1 by the controller 20 may be in a manner other than that described above. Other controls can also be similarly modified in various ways.

[0032] The power transmission unit 28 transmits power from the electric motor 12 to the blade 34 via the slider 29 and the blade holder 32. The slider 29 is rectangular in shape. The slider 29 extends vertically. The blade holder 32 is held at the lower end of the slider 29. The slider 29 is reciprocating in the vertical direction. The blade holder 32 is reciprocating in the vertical direction. The power transmission section 28 includes an intermediate gear 65, a support shaft 66, a spacer 67, a plurality (two) needle bearings 68, and a guide roller section 69.

[0033] The intermediate gear 65 has a gear section 65G, a first cam section 65E, and a second cam section 65F. The intermediate gear 65 is cylindrical and extends in the front-to-back direction. The intermediate gear 65 reduces the rotation of the motor shaft 53 and transmits it to the slider 29. The gear section 65G is positioned in front of the intermediate gear 65. Multiple teeth are formed on the outer curved surface of the gear section 65G. The outer diameter of the gear section 65G is larger than the outer diameter of the rear of the intermediate gear 65. The gear section 65G meshes with the pinion section 54. The first cam portion 65E is located at the rear of the intermediate gear 65. The outer surface of the first cam portion 65E is a cylindrical surface that is eccentric with respect to the virtual central axis of the intermediate gear 65 in the front-rear direction. The second cam portion 65F is located in the center of the intermediate gear 65. The outer surface of the second cam portion 65F is a cylindrical surface that is eccentric with respect to the virtual central axis of the intermediate gear 65 in the front-rear direction.

[0034] The support shaft 66 is cylindrical and extends in the front-to-back direction. The rear end of the support shaft 66 is fixed to the upper opening of the gear housing 42 via a cylindrical spacer 67. The support shaft 66 protrudes forward from the rear inner surface of the gear housing 42.

[0035] Each needle bearing 68 is positioned around the central part of the support shaft 66. Two needle bearings 68 are arranged one behind the other. Each needle bearing 68 supports the intermediate gear 65 so that it can rotate around its virtual central axis. Each needle bearing 68 and support shaft 66 is positioned radially inward of the intermediate gear 65.

[0036] The guide roller section 69 includes a shaft 70, a needle bearing 72, and a guide roller 74. The shaft 70 is cylindrical. The shaft 70 extends in the front-rear direction. The rear end of the shaft 70 is fixed to the gear section 65G. The shaft 70 is positioned eccentrically on the gear section 65G. The shaft 70 protrudes forward from the front surface of the gear section 65G. The needle bearing 72 is supported at the front of the shaft 70. The guide roller 74 is cylindrical. The guide roller 74 is supported by a needle bearing 72 so as to be rotatable around a virtual central axis in the longitudinal direction. The guide roller 74 is located in front of the gear section 65G.

[0037] Slider 29 extends vertically and is movable up and down. The slider 29 includes a roller guide 80, a shaft 82, and a slider body 84. The roller guide 80 extends to the left and right and has grooves that extend to the left and right. The guide roller 74 is positioned in the grooves of the roller guide 80 so as to be movable from side to side. The shaft 82 is cylindrical and extends to the left and right. The slider body 84 is a rectangular tube extending vertically. The slider body 84 is attached to the roller guide 80 via a shaft 82. The shaft 82 passes between the lower end of the roller guide 80 and the upper end of the slider body 84. The slider body 84 is able to swing back and forth around the shaft 82. The guide roller 74 of the guide roller section 69, positioned eccentrically on the intermediate gear 65, moves left and right within the roller guide 80 of the slider 29, thereby transmitting only vertical movement to the roller guide 80. As a result, the slider 29 reciprocates vertically due to the rotation of the intermediate gear 65. The guide roller 74 and roller guide 80 convert rotational force into reciprocating motion.

[0038] The slider guide 30 is cylindrical and extends vertically. The slider body 84 passes radially inward through the slider guide 30. The slider guide 30 guides the reciprocating slider 29. The slider guide 30 is held in the gear housing 42. The dust seal 31 is ring-shaped and elastic. The dust seal 31 is held in place by the gear housing 42. The slider body 84 passes radially inward through the inner bore of the dust seal 31. The dust seal 31 contacts the slider 29 and prevents dust from entering the housing 10.

[0039] The blade holder 32 is held by the slider body 84. The blade holder 32 is connected to the lower end of the slider body 84. The blade holder 32 attaches to and detaches the blade 34. The blade 34 extends vertically and has a workpiece-acting portion on one of its longitudinal sides that acts on the workpiece. The workpiece-acting portion is, for example, a saw blade for cutting the workpiece. The blade 34 is attached to the blade holder 32 at its upper end with the workpiece-acting portion facing forward. The blade 34 can be attached to the blade holder 32 without using tools such as a wrench, i.e., tool-less. The blade holder 32 will be described in more detail later.

[0040] The tool opener 35 is lever-shaped and extends to the left and right. The tool opener 35 is rotatable around a virtual vertical axis located within its right end. The user can open the tool opener 35 by extending its left end forward. The tool opener 35 is biased by an elastic spring 86 to pull its left end backward in a rotational direction, i.e., in the closing direction. A blade holder 32 is located adjacent to the left end of the tool opener 35, on the inner side in the left-right direction. The tool opener 35 is made of a translucent resin. The tool opener 35 transmits light from a light source. However, the tool opener 35 does not necessarily need to be translucent.

[0041] The orbital motion unit 36 ​​includes a push plate 90, a holder shaft 91, a roller holder 92, a roller shaft 94, a back roller 96, and a needle bearing 97. The push plate 90 is plate-shaped and extends in all directions (up, down, left, and right). The push plate 90 has a first cam hole at its upper end. A first cam portion 65E is located radially inward of the first cam hole. The first cam portion 65E moves the push plate 90 up and down via the inner surface of the first cam hole. The first cam portion 65E is eccentric to the guide roller portion 69 in the opposite phase. The holder shaft 91 is cylindrical in shape, extending to the left and right. The roller holder 92 is located below the push plate 90. The roller holder 92 has an upper plate portion 92U and a plurality (2) of arm portions 92A. The upper plate portion 92U extends in the front, back, left, and right directions. Each arm portion 92A extends in the front, back, up, and down directions, and extends downward and forward from the left or right side of the upper plate portion 92U. A holder shaft 91 is placed between the centers of each arm portion 92A. The roller holder 92 is held in the gear housing 42 in a state that allows it to swing around the holder shaft 91. The roller shaft 94 is cylindrical in shape and extends to the left and right. The roller shaft 94 is placed between the lower ends of each arm portion 92A in the roller holder 92. The back roller 96 is cylindrical in shape and extends to the left and right. The back roller 96 is rotatably supported on the roller shaft 94 via needle bearings 97. The back roller 96 can contact the rear edge of the blade 34 without hindering the reciprocating motion of the blade 34.

[0042] The orbital switching section 37 has a shaft section 37S and a knob section 37K. The shaft portion 37S is shaft-shaped and extends to the left and right. The cross-section of the central part of the shaft portion 37S is semicircular when viewed from right to left. The central part of the shaft portion 37S is semi-cylindrical. The shaft portion 37S is positioned above the upper plate portion 92U of the roller holder 92 of the orbital motion portion 36 and behind the lower end of the push plate 90. The knob portion 37K is fixed to the left end of the shaft portion 37S. The knob portion 37K extends radially outward from the shaft portion 37S. The user can rotate the orbital switching unit 37 around the virtual central axis of the shaft unit 37S by operating the knob 37K. The knob 37K is rotatable between the marks marked "0" and "III" formed on the outer surface of the gear housing 42. Between these marks, one recess is located on the "0" side and one recess is located on the "III" side. Two recesses are located between the recess on the "0" side and the recess on the "III" side, and adjacent to the recess on the "III" side. That is, three recesses are arranged side by side on the "III" side. Note that some or all of the recesses and marks may be omitted.

[0043] The user can, as needed, switch the mode of orbital motion of the blade 34, which is based on the forward and backward oscillation of the back roller 96 that contacts the blade 34, by operating the knob 37K. When the knob 37K of the orbital switching unit 37 is set to the "0" position, the semi-cylindrical part of the shaft 37S is in a rotational position with its curved surface facing downwards, and contacts the upper plate 92U of the roller holder 92. In this case, regardless of the vertical position of the push plate 90 which moves up and down by the first cam 65E, the back roller 96 remains in the same position and does not swing, and the blade 34 does not perform orbital motion. When the knob 37K of the orbital switching unit 37 is in a position away from the "0" mark, the semi-cylindrical portion of the shaft 37S moves away from the upper plate 92U of the roller holder 92. As a result, the vertically moving push plate 90 causes the roller holder 92 and the back roller 96 to swing via the upper plate 92U, and the back roller 96 applies a force in the front-rear direction to the blade 34. This force leads to the swinging of the slider body 84, blade holder 32, and blade 34 around the shaft 82. The blade 34, with the addition of a front-rear swinging motion to its vertical movement, performs orbital motion as if following a virtual ellipse when viewed from right to left. As the knob 37K moves away from the "0" mark, the semi-cylindrical portion of the shaft 37S gradually moves away from the upper plate 92U. Therefore, the magnitude of the oscillation of the roller holder 92 and the back roller 96 changes depending on the rotational position of the knob 37K. For example, when the knob 37K rotates to the rotational position of the "III" mark, the magnitude of the oscillation of the roller holder 92 and the back roller 96 becomes maximum. Thus, the manner of orbital motion changes depending on the rotational position of the knob 37K. The amount of orbital motion can be switched to three different sizes by switching the position of the knob 37K according to the three recesses or marks described above.

[0044] The counterweight section 38 includes a counterweight 100 and a shaft 102. The counterweight 100 is plate-shaped and extends in all directions (up, down, left, and right). The counterweight 100 has a cam hole located in the center in the vertical direction and an upper hole located above it. The second cam portion 65F of the intermediate gear 65 is placed in the cam hole of the counterweight 100. The second cam portion 65F is eccentric to the guide roller portion 69 in the opposite phase. The shaft 102 extends in the front-rear direction. The shaft 102 is held in the gear housing 42. The shaft 102 spans between the front wall and the rear wall of the gear housing 42. The central part of the shaft 102 fits into the upper hole of the counterweight 100. The counterweight 100 moves up and down in the opposite phase to the slider 29, blade holder 32, and blade 34, due to a second cam portion 65F that is eccentrically positioned in the opposite phase to the guide roller portion 69. Therefore, vibrations caused by the reciprocating motion of the slider 29, blade holder 32, and blade 34 are suppressed by the counterweight 100.

[0045] The guard 39 extends vertically. The upper end of the guard 39 is held by the gear housing 42. The lower end of the guard 39 is adjacent to the upper surface of the base portion 6. Blade 34 is positioned behind Guard 39.

[0046] The base unit 6 is located on the underside of the main unit 2 and is attached to the main unit 2. The base portion 6 includes a base 110, a base plate 112, a number of screws (four, not shown), a nut 114, a bolt 116, and a retaining plate 117.

[0047] The base 110 is made of die-cast aluminum alloy and is plate-shaped, extending in all directions (front, back, left, and right). The front part of the base 110 is bifurcated. The blade 34 can pass between the bifurcated parts of the base 110. The base 110 has ruler mounting sections 119. The ruler mounting sections 119 are located at each front end of the bifurcated portion of the base 110. One ruler (not shown) can be inserted into the ruler mounting section 119.

[0048] The base plate 112 is made of metal, specifically steel plate, and is plate-shaped. By positioning the base plate 112 on the lower surface of the base portion 6, wear of the base portion 6 due to contact with the workpiece is suppressed. The base plate 112 is attached to the underside of the base 110 with four screws.

[0049] The nut 114 is held at the rear lower part of the gear housing 42. The nut 114 is located in the center of the main body 2 in the left-right direction. Furthermore, the nut 114 may be a component of the main body 2, or it may be an independent component.

[0050] Bolt 116 extends vertically, with its head facing downwards. The retaining plate 117 is plate-shaped. The cross-section of the retaining plate 117 is arch-shaped. A bolt hole is provided in the center of the retaining plate 117. The retaining plate 117 may be omitted. The bolt 116 passes through the bolt hole in the retaining plate 117 and the cross-shaped hole provided in the base 110, and is inserted into the nut 114. The base portion 6 is fixed to the gear housing 42 by a bolt 116 that fits into a nut 114, and a retaining plate 117.

[0051] The user may, as necessary, change at least one of the orientation of the main body 2 relative to the base 6 (the angle of tilt of the main body 2 to the left or right) and the relative position of the main body 2 relative to the base 6 in the front-rear direction. To change the orientation of the main body 2 relative to the base 6, the user loosens the bolt 116. This releases the base 6 from its fixing via the retaining plate 117, allowing the bolt 116 to move along the cross-shaped holes. By moving the bolt 116 along the portions extending to the left and right of the cross-shaped holes, the user can change the orientation of the main body 2 relative to the base 6, or in other words, change the inclination angle of the main body 2 relative to the base 6. The user then tightens the bolt 116 in the desired orientation to complete the change. Furthermore, when changing the relative position of the main body 2 with respect to the base 6 in the front-to-back direction, the user loosens the bolt 116, moves the bolt 116 along the portion extending front to back from the cross-shaped hole, and tightens the bolt 116 at the desired position. When the bolt 116 is located at the intersection of the front-to-back and left-to-right portions of the cross-shaped hole, the main body 2 is in its basic position relative to the base 6. Figures 1 to 3 show the jigsaw 1 with the main body 2 in its basic position.

[0052] The blade holder 32 will be described in more detail below. Figures 4 and 5 are exploded perspective views of the blade 34, blade holder 32, and slider body 84. Note that Figures 4 and 5 show the slider before blade insertion.

[0053] The blade 34 has multiple (two) protrusions 34C at its upper end, which is the end on the main body 2 side. Each protrusion 34C is positioned front to back. The front protrusion 34C protrudes forward from the front edge of the upper end of the blade 34. The rear protrusion 34C protrudes backward from the rear edge of the upper end of the blade 34. The upper end of the blade 34 is formed in a "+" shape by the protrusions 34C.

[0054] The slider body 84 has a guide portion 84G at its lower end, which is the end opposite to the main body portion 2, i.e., the end opposite the main body. The guide portion 84G is a cylindrical block made of metal having grooves, slits, and holes, and is fixed to the lower end of the other part of the slider body 84. The guide portion 84G may be formed integrally with the other rectangular tubular part of the slider body 84. The guide portion 84G includes a blade receiving groove 84C, a guide hole 84H, an engagement portion guide slit 84S, a fastener mounting hole 84P, and a flange portion 84F.

[0055] The blade receiving groove 84C is located in the center of the guide section 84G in the left-right direction and extends in the front-back, up-down, and rear-right directions. The lower part of the blade receiving groove 84C reaches the front and rear outer surfaces of the guide section 84G, forming the slit portion of the blade receiving groove 84C. The portion of the blade receiving groove 84C other than the slit portion is a hole-like area formed by combining a rectangular space and a semi-cylindrical space when viewed from below and above. The semi-cylindrical space is located to the left of the rectangular space. The inner surface on the left side of the hole-like area of ​​the blade receiving groove 84C is formed in a semi-cylindrical shape. The guide hole 84H extends to the left and right, is located to the right of the blade receiving groove 84C, and communicates with the blade receiving groove 84C. The engagement guide slit 84S is located to the left of the blade receiving groove 84C. The engagement guide slit 84S communicates with the blade receiving groove 84C. The engagement guide slit 84S reaches the left outer surface of the guide portion 84G and extends vertically. The fastener mounting hole 84P is located in the circumferential direction between the blade receiving groove 84C and the engagement part guide slit 84S. The fastener mounting hole 84P extends diagonally from the front left to the rear right and communicates with the blade receiving groove 84C. The flange portion 84F is positioned at the upper end of the guide portion 84G and protrudes radially outward from the adjacent portion. The flange portion 84F is ring-shaped when viewed from below and upward. Furthermore, at least one of the grooves, slits, and holes may be changed to other forms, for example, by making the engagement part guide slit 84S an engagement part guide groove that does not reach the outer surface of the guide part 84G. Also, the fastener mounting hole 84P does not need to be in communication with the blade receiving groove 84C.

[0056] The blade holder 32 includes a first pressing member 130, a sleeve 132, a first biasing member 134, a fastener 136, a circlip 138, a cover 140, a second pressing member 142, and a second biasing member 144.

[0057] The first pressing member 130 is pin-shaped and comprises a first pressing member body 130B and a first pressing member head 130H. The first pressing member body 130B is a rectangular prism shape extending to the left and right, and is slidably inserted into the guide hole 84H. The direction of movement of the first pressing member 130 is left and right. The first pressing member 130 is movable in a direction approaching and moving away from the blade 34. The head portion 130H of the first pressing member is positioned to the right of the main body 130B of the first pressing member. The head portion 130H of the first pressing member protrudes upward, downward, forward, and backward from the right end of the main body 130B of the first pressing member. Therefore, the occurrence of the entire first pressing member 130 entering radially inward from the radially outward opening of the guide hole 84H is suppressed. The first pressing member 130 is positioned radially inward of the sleeve 132. The first pressing member 130 is capable of pressing the blade 34.

[0058] As shown in Figure 6, the sleeve 132 is cylindrical and cap-shaped. The sleeve 132 includes a sleeve body 132B, a handle portion 132H, a circlip mounting groove 132S, a first cam surface 132C as a cam surface, a blade passage hole 132P, a plurality (two) blade holding portions 132L, an engagement portion guide portion 132G as an engaged portion, and a second cam surface 132D. Note that the direction in Figure 6 is when the blade is locked.

[0059] The sleeve body 132B is a cap-shaped portion having a cylindrical portion that extends vertically and a lower surface portion. The handle portion 132H is a lever-shaped part that protrudes radially outward from the left side of the sleeve body 132B. The circlip mounting groove 132S is formed in a ring shape with a slit on the inner surface of the upper opening of the sleeve body 132B. The slit is located at the base of the handle portion 132H. The circlip mounting groove 132S is recessed radially outward with respect to the adjacent inner surface.

[0060] The first cam surface 132C is formed on the right side of the lower inner surface of the sleeve body 132B, and radially outward from the first pressing member 130. The first cam surface 132C is formed such that its inner diameter gradually decreases from the front to the rear. The first pressing member 130 is positioned radially inward of the first cam surface 132C. The radially outward surface, i.e., the right surface, of the head 130H of the first pressing member is in contact with the first cam surface 132C. The first pressing member 130 can traverse the first cam surface 132C by rotational movement relative to the sleeve 132.

[0061] The blade passage hole 132P is formed on the lower surface of the sleeve body 132B. The blade passage hole 132P is "φ" shaped. The diameter of the circular portion of the blade passage hole 132P, when viewed from below upward, is the same as or slightly larger than the size in the front-to-back direction (i.e., the width direction of the blade 34) of the upper end of the blade 34 where the protrusion 34C is not located. The size of the long side of the rectangular portion of the blade passage hole 132P, when viewed from below upward, is the same as or slightly larger than the size in the front-to-back direction of the upper end of the blade 34 where the pair of protrusions 34C are located. Each blade retaining portion 132L is positioned front to back. Each blade retaining portion 132L is located on the lower surface of the sleeve body 132B, adjacent to the blade passage hole 132P. More specifically, the front blade retaining portion 132L is positioned counterclockwise when viewed from below and above, relative to the front end of the rectangular portion that extends radially outward from the circular portion of the blade passage hole 132P. The rear blade retaining portion 132L is positioned counterclockwise when viewed from below and above, relative to the rear end of the rectangular portion that extends radially outward from the circular portion of the blade passage hole 132P.

[0062] The engagement guide portion 132G is located on the left inner surface of the sleeve body 132B, to the left of the first cam surface 132C. The engagement guide portion 132G is formed in a groove shape with a larger inner diameter than the adjacent first cam surface 132C. The engagement guide portion 132G is located to the left of the rear blade holding portion 132L. The second cam surface 132D is formed on the inner surface of the left side of the lower surface of the sleeve body 132B, in a portion adjacent to the blade passage hole 132P and adjacent to the blade holding portion 132L. The second cam surface 132D is located to the left of the lower end of the engagement portion guide portion 132G. The second cam surface 132D is a cam surface whose vertical position, i.e., height, changes. The height of the second cam surface 132D is highest on the side closest to the engagement portion guide portion 132G and gradually decreases as it moves circumferentially towards the left front.

[0063] The first biasing member 134 is an elastic body and is a torsion spring. The first biasing member 134 is ring-shaped and extends in the front, back, left, and right directions. The first biasing member 134 biases the sleeve 132 in a counterclockwise direction when viewed from below and upward. The first biasing member 134 biases the first pressing member 130 via the sleeve 132. The upper end of the first biasing member 134 extends radially outward and is held by the handle portion 132H of the sleeve 132. The lower end of the first biasing member 134 extends vertically and is secured by a fastener 136. In Figures 4 and 5, the first biasing member 134 and the fastener 136 are shown in contact with each other in order to be clearly illustrated in the perspective view. The fastener 136 is pin-shaped and is inserted into the fastener mounting hole 84P of the guide portion 84G of the slider body 84. The first biasing member 134 is positioned above the first pressing member 130. Alternatively, the first biasing member 134 may be positioned below the first pressing member 130. The first biasing member 134 is positioned radially inward of the sleeve 132.

[0064] The circlip 138 is positioned above the flange portion 84F of the guide portion 84G and is held in the circlip mounting groove 132S of the sleeve 132. The circlip 138 prevents the sleeve 132 from coming off the guide portion 84G. The cover 140 is ring-shaped and is fitted into the upper end opening of the sleeve 132, covering the opening. The cover 140 prevents dust from entering the sleeve 132.

[0065] The second pressing member 142 is pin-shaped and extends vertically, and has a pressing portion 142P, a tongue portion 142T, and an engaging portion 142F. The pressing portion 142P is cylindrical in shape and extends vertically, and is positioned at the upper end of the second pressing member 142. The virtual center line or its extension extending vertically from the pressing portion 142P passes through the attached blade 34. The tongue portion 142T is plate-shaped with a cylindrical surface. The tongue portion 142T extends downward from the left side of the lower end of the pressing portion 142P. The cylindrical surface of the tongue portion 142T is continuous with the left cylindrical surface of the pressing portion 142P. The tongue portion 142T of the second pressing member 142 is positioned radially inward of the first biasing member 134. The second pressing member 142 penetrates the inner space of the first biasing member 134. The tongue portion 142T connects the pressing portion 142P and the engaging portion 142F. The pressing portion 142P, the tongue portion 142T, and the engaging portion 142F are integral. The vertically extending tongue portion 142T is offset in the left-right direction with respect to the virtual center line of the pressing portion 142P. The engaging portion 142F is plate-shaped and extends in all directions (up, down, left, and right). The engaging portion 142F protrudes to the left from the left surface of the lower end of the tongue portion 142T. The pressing portion 142P and the tongue portion 142T are positioned vertically movably within the blade receiving groove 84C of the guide portion 84G. The left surface of the pressing portion 142P and the left surface of the tongue portion 142T are formed in a series of semi-cylindrical surfaces and are in contact with the semi-cylindrical inner surface of the left side of the blade receiving groove 84C. The movement of the pressing portion 142P and the tongue portion 142T is guided by the blade receiving groove 84C. The engaging portion 142F is positioned vertically movably within the engaging portion guide slit 84S of the guide portion 84G. The vertical movement of the engaging portion 142F is guided by the engaging portion guide slit 84S. In addition, the engaging portion 142F is positioned vertically movably within the engaging portion guide portion 132G of the sleeve 132. Part of the vertical movement of the engaging portion 142F is guided by the engaging portion guide portion 132G. The second pressing member 142 is capable of pressing the blade 34.

[0066] The second biasing member 144 is an elastic body and is a compression spring. The second biasing member 144 extends vertically. The second biasing member 144 biases the second pressing member 142 downward. The second biasing member 144 is positioned above the second pressing member 142. The second biasing member 144 is placed in the upper end of the blade receiving groove 84C.

[0067] The blade holder 32 is assembled to the guide portion 84G of the slider body 84 as follows. For the sake of ease of understanding, the explanation is given in the direction shown in the drawing, but the actual assembly work may be carried out in orientations of the various components that differ from the direction described below. Specifically, the second biasing member 144 and the second pressing member 142 are placed in the blade receiving groove 84C. The circlip 138 is positioned on the upper side of the flange portion 84F. Furthermore, the first pressing member 130 is placed in the guide hole 84H. In addition, the fastener 136 is placed in the fastener mounting hole 84P in a manner that it does not protrude radially outward. Then, with the upper end of the first biasing member 134 attached to the handle portion 132H of the sleeve 132, the sleeve 132 is moved relatively outward radially from below the guide portion 84G. The circlip 138 enters the circlip mounting groove 132S. The engaging portion 142F of the second pressing member 142 enters the engaging portion guide portion 132G of the sleeve 132. Subsequently, the radially outward end of the fastener 136 is moved so that it extends radially outward from the fastener mounting hole 84P, and the lower end of the second biasing member 144 is hooked onto it. Finally, the cover 140 is fitted into the upper opening of the sleeve 132.

[0068] The blade holder 32 can be automatically installed with a single touch and without tools, simply by receiving the blade 34 between the first pressing member 130 and the second pressing member 142. The installation of the blade 34 will be described below in the following order: before blade 34 insertion, during blade 34 insertion, when blade 34 is pushed in, and when blade 34 is locked. These four states are distinguished for the sake of explanation, and the actual installation of the blade 34 is performed in a series of actions over a short period of time. Figure 7A is a bottom view of the blade holder 32 before the blade 34 is inserted. Figure 7B is a bottom view of the blade holder 32 when the blade 34 is locked. Figure 8A is a cross-sectional view of the blade holder 32 along line AA before and during the insertion of the blade 34. Figure 8B is a cross-sectional view of Figure 8A along line CC. Figure 9A is a cross-sectional view of the blade holder 32 along line AA when the blade 34 is pushed in. Figure 9B is a cross-sectional view of Figure 9A along line DD. Figure 10A is a cross-sectional view of the blade holder 32 along line AA when the blade 34 is locked. Figure 10B is a cross-sectional view of Figure 10A along line EE. Figure 11A is a cross-sectional view of Figure 8B along line FF. Figure 11B is a cross-sectional view of Figure 9B along line GG. Figure 11C is a cross-sectional view of Figure 10B along line HH.

[0069] Before the blade 34 is inserted, the rectangular portion of the blade passage hole 132P in the sleeve 132 is facing in the front-to-back direction. Also, the handle portion 132H is located slightly to the left and forward (at the 1 o'clock position in Figures 7A and 8B). In addition, the first biasing member 134 biases the sleeve 132 in a clockwise direction when viewed from below and upward (Figure 8B). The second biasing member 144 is in its natural length state, or a state relatively close to its natural length. Furthermore, the engaging portion 142F of the second pressing member 142 is inserted into the engaging portion guide portion 132G. Therefore, rotation in the clockwise direction of the sleeve 132, which is biased by the first biasing member 134, is suppressed. In other words, the sleeve 132 is prevented from rotating. Also, the lower edge of the engaging portion 142F is in contact with the inner surface of the lower surface of the sleeve 132. Therefore, the second pressing member 142 is prevented from coming off. Furthermore, the engaging portion 142F engages with the engaging portion guide portion 132G, thereby stopping the rotation of the sleeve 132. In addition, the first pressing member 130 is located radially inward of the large-diameter portion of the first cam surface 132C, and the first pressing member body 130B can be easily moved to the right and easily retracted from the blade receiving groove 84C.

[0070] When the ends of the blade 34 on each protrusion 34C are inserted into the blade holder 32 from this state, the ends of the blade 34 first pass through the rectangular portion of the blade passage hole 132P. Passing through this rectangular portion guides the blade 34 into a mounting position where it spreads out in the front, back, up, and down directions. Next, the end of the blade 34 passes between the first pressing member 130 and the second pressing member 142. Then, the end of the blade 34 contacts the lower surface of the pressing portion 142P of the second pressing member 142 (dotted line in Figures 8A, 8B, and 11A). When inserting the blade 34 as described above, and when pushing in the next blade 34, operation of the tool opener 35 is unnecessary. The tool opener 35 is used only when removing the blade 34.

[0071] When the blade 34 is moved further upward, it is time for the blade 34 to be pushed in, which is when the blade 34 is pushed in against the second pressing member 142. At this time, the pressing portion 142P of the second pressing member 142 is pushed up by the end of the blade 34 against the biasing force of the second biasing member 144. The left side of the pressing portion 142P and the left side of the tongue portion 142T of the second pressing member 142 are guided to the left side of the blade receiving groove 84C. The engaging portion 142F of the second pressing member 142 is guided to the engaging portion guide slit 84S and the engaging portion guide portion 132G. Each protrusion 34C of the blade 34 is guided to the corresponding slit portion of the blade receiving groove 84C.

[0072] Then, when the lower edge of the engaging portion 142F of the second pressing member 142 is above the upper edge of the engaging portion guide portion 132G of the sleeve 132, the engaging portion 142F disengages from the engaging portion guide portion 132G, and the engagement of the engaging portion 142F with respect to the engaging portion guide portion 132G is released, the sleeve 132 automatically rotates in a clockwise direction when viewed from below to above due to the biasing force of the first biasing member 134. The rotation of the sleeve 132 stops when the first pressing member 130 reaches a predetermined state. This predetermined state is when the head 130H of the first pressing member contacts the first cam surface 132C of the sleeve 132, and the left side of the body 130B of the first pressing member presses against the right side of the blade 34. As the sleeve 132 rotates, the first pressing member 130 moves to the left along the first cam surface 132C. After the sleeve 132 rotates, the first pressing member 130 is biased by the first biasing member 134 via the sleeve 132. The direction of biasing here is a clockwise direction when viewed from below to above on the first pressing member 130, which is converted to a leftward direction on the first pressing member 130 by the first cam surface 132C. The first biasing member 134 is retracted by rotating its arm 50° from the free angle when the blade 34 is not present, and retracted by rotating its arm 60° from the free angle when the blade 34 is inserted. The first pressing member 130 automatically presses the blade 34 when the second pressing member 142 is pushed upward. The angle from the free angle of the first biasing member 134 in each state may be changed in various ways from the values ​​described above as appropriate. At this time, the rectangular portion of the blade passage hole 132P of the sleeve 132 is oriented diagonally from the rear right to the front left when viewed from below and above, and each protrusion 34C of the blade 34 is located above the lower surface of the sleeve body 132B. The lower edge of each protrusion 34C is in contact with the corresponding blade holding portion 132L. Each protrusion 34C is biased toward the corresponding blade holding portion 132L by the second biasing member 144. Furthermore, the upper edge of each protrusion 34C is separated from the upper end of the slit portion of the corresponding blade receiving groove 84C. In addition, the handle portion 132H is located to the left (at the 3 o'clock position in Figures 7B and 10B).

[0073] Upon completion of the rotation of the sleeve 132, the blade holder 32 locks the blade 34 in place. When the blade 34 is locked, it is sandwiched between the first pressing member 130 and the left inner surface of the blade receiving groove 84C of the slider body 84, as shown in Figure 10B. The central part of the right side of the blade 34 in the front-rear direction is in contact with the left end surface of the first pressing member 130. The front and rear parts of the left side of the blade 34 are in contact with the left inner surface of the blade receiving groove 84C. In addition, each protrusion 34C of the blade 34 is held by the corresponding blade holding part 132L in the sleeve 132. Thus, the blade 34 is prevented from coming off. The virtual center line of the blade 34 attached to the blade holder 32 in the extending direction, i.e., the vertical direction, is shifted toward the first pressing member 130 in the direction perpendicular to the reciprocating motion, i.e., the left-right direction, relative to the extending direction, i.e., the virtual center line of the blade holder 32 in the extending direction, i.e., the vertical direction, and the blade 34 is offset to the right with respect to the center of the blade holder 32.

[0074] On the other hand, the blade 34 is removed as follows: In other words, when the power to the jigsaw 1 is turned off, and the left side of the tool opener 35 is extended forward, the left rear side of the tool opener 35 moves the handle portion 132H of the sleeve 132 against the biasing force of the first biasing member 134. As a result, the sleeve 132 rotates counterclockwise when viewed from below and above, changing from the state in Figure 7B to the state in Figure 7A. The engaging portion 142F of the second pressing member 142, due to the downward biasing force of the second biasing member 144, relatively follows the second cam surface 132D during the rotation of the sleeve 132, and at the end of the rotation of the sleeve 132, enters the engaging portion guide portion 132G from the end of the second cam surface 132D, stopping the rotation of the sleeve 132. At this time, the large-diameter portion of the first cam surface 132C of the sleeve 132 is located to the right of the first pressing member 130, allowing the first pressing member 130 to move freely to the right, opposite to the blade 34, without being subjected to the biasing force of the first biasing member 134. Also, the rectangular portion of the blade passage hole 132P in the sleeve 132 changes from an oblique direction to a front-to-back direction, becoming a rotational position that allows the blade 34 to pass through each of its protrusions 34C. Each protrusion 34C disengages from the corresponding blade holding portion 132L due to the rotation of the sleeve 132. As a result, the blade 34 is pushed downward via the second pressing member 142 by the biasing force of the second biasing member 144.

[0075] In the blade holder 32, the first biasing member 134 that biases the first pressing member 130 is offset from the first pressing member 130 that presses the blade 34 in the vertical direction, which is the direction of extension and reciprocating motion related to the slider body 84, the blade holder 32, and the blade 34, and is positioned above the first pressing member 130. More specifically, regardless of the position in which the movable first biasing member 134 is positioned, it does not overlap with the first pressing member 130 when viewed from a direction perpendicular to the extension direction of the slider body 84 (front-to-back direction, left-to-right direction, etc., i.e., the radial direction of the cylindrical sleeve 132). In other words, regardless of the position in which the movable first biasing member 134 is positioned, it does not overlap with the first pressing member 130 when viewed from the direction of movement of the first pressing member 130 (i.e., left-to-right direction). In other words, the first biasing member 134 is positioned to avoid the direction of movement of the first pressing member 130. Therefore, in the jigsaw 1, the size of the first biasing member 134 in at least one of the front-to-back and left-to-right directions, i.e., the size of the first biasing member 134 in the front-to-back and left-to-right directions, can be suppressed and its size optimized. Consequently, the size of the blade holder 32 in the front-to-back and left-to-right directions is suppressed, and the diameter of the blade holder 32 is reduced. As a result, the visibility of the part adjacent to the blade 34 is improved, and the workability of processing and other operations in the jigsaw 1 is improved. Furthermore, in the jigsaw 1, the biasing action of the first biasing member 134 and the biasing action of the second biasing member 144 allow the user to easily attach the blade 34 by simply inserting it into the blade holder 32 without operating the tool opener 35. Moreover, the user can easily remove the attached blade 34 by simply moving the handle portion 132H forward by operating the tool opener 35.

[0076] Furthermore, in the blade holder 32, the blade 34 is held mainly by being clamped between the first pressing member 130 and the second pressing member 142, and the upper edges of each protrusion 34C are separated from the upper ends of the slits of the blade receiving groove 84C. Therefore, wear on the upper and lower edges of each protrusion 34C is suppressed. Consequently, the occurrence of changes in the mounting angle of the blade 34 is suppressed, and the occurrence of situations that affect workability is suppressed.

[0077] An example of the operation of jigsaw 1 is described.

[0078] The user attaches the blade 34 to the blade holder 32. The blade 34 is attached to the blade holder 32 by passing its upper end through it and then pushing it in slightly at the end. The user also inserts the charged battery 8 into the battery mounting section 18.

[0079] If the user operates the ON / OFF switch 26 within a predetermined time after operating the lock-off switch 27, the controller 20 controls and supplies power from the battery 8 to the electric motor 12 so that the motor shaft 53 rotates at a controlled speed. The electric motor 12 is driven at a speed corresponding to the rotation position of the speed adjustment switch 22. Furthermore, the rotation direction of the motor shaft 53 may be switchable.

[0080] The rotation of the motor shaft 53 causes the fan 14 to rotate, and within the main body 2, an airflow (i.e., wind) is formed from the gap between the intake port 44 and the housing 10, extending radially outward from the fan 14. Such wind cools the internal mechanisms of the jigsaw 1, including the electric motor 12 and the controller 20.

[0081] Furthermore, the rotational force of the motor shaft 53 is reduced by the intermediate gear 65 and then converted into reciprocating motion which is transmitted to the slider 29, blade holder 32, and blade 34. The vibration of the jigsaw 1 is suppressed by the counterweight section 38. Furthermore, the user can switch the mode of orbital motion of the blade 34 by operating the knob 37K as needed. Furthermore, the user can adjust the reciprocating speed of the blade 34 using the speed adjustment switch 22 as needed.

[0082] The user then applies the workpiece-acting portion of the reciprocating blade 34 to the workpiece portion of the workpiece and moves the blade 34 relative to the workpiece. As a result, the workpiece portion of the workpiece is cut by the blade 34.

[0083] When processing is complete, the user operates the ON / OFF switch 26 to turn off the electric motor 12. At this time, the blade 34 stops. The user removes the battery 8 and blade 34 as appropriate. The blade can be removed tool-less and with a single touch by operating the tool opener 35.

[0084] Furthermore, the above forms and examples of their modifications are not limited to those described above, and for example, the following modifications may be made as appropriate. In the jigsaw 1, even if the second pressing member 142 is pushed in by the blade 34, the first pressing member 142 does not have to automatically press the blade 34. For example, the blade 34 may be made attachable by the user maintaining the forward movement of the tool opener 35.

[0085] The reduction mechanism from the motor shaft 53 to the blade 34 in the jigsaw 1 may be replaced with a reduction mechanism other than the pinion section 54 and the intermediate gear 65. The reciprocating motion conversion mechanism in the jigsaw 1 that converts the rotational driving force from the motor shaft 53 to the blade 34 into reciprocating motion may be replaced with a mechanism other than the one using the guide roller section 69 and the roller guide 80. The jigsaw 1 may be AC-driven using a commercial power supply by having a power cord instead of a battery mounting section 18. The material of at least one of the various cases and housings may be changed to resin, metal, or a composite thereof. The division of the housing 10 may be changed from those described above. In addition, at least one of the various components, parts, presence or absence of installation, material, arrangement, structure, and type may be changed as appropriate. Furthermore, the above configuration or its modifications may also be applied to jigsaws that attach cutting tools other than the blade 34. In addition, the above-described form or its modifications may be applied to reciprocating cutting tools other than jigsaws, such as reciprocating saws. [Explanation of Symbols]

[0086] 1 Jigsaw 32 Blade Holder 34 blades 130 First pressing member 132 sleeves 132C First cam surface (cam surface) 132G Engaging part guide part (engaged part) 134 First biasing member 142 Second pressing member 142F Engagement part 142P Pressing part 142T Tongue 144 Second biasing member

Claims

1. The blade attachment / detachment mechanism is designed to be reciprocating, The aforementioned blade attachment / detachment section is A first pressing member is movable in a direction approaching and moving away from the blade and is capable of pressing the blade, A first biasing member that biases the first pressing member, The blade is pressed by a second pressing member which is capable of pressing the blade in a direction different from the direction of pressing by the first pressing member, A second biasing member that biases the second pressing member, It has, When the second pressing member is pressed by the blade, the first pressing member automatically presses against the blade. The first biasing member is positioned to avoid the direction of movement of the first pressing member. A reciprocating cutting tool characterized by the following features.

2. The second pressing member is movable in the direction of the reciprocating motion, The direction of movement of the first pressing member is perpendicular to the direction of movement of the second pressing member. The first biasing member is positioned in a location offset from the first pressing member in the direction of the reciprocating motion. The reciprocating cutting tool according to feature 1.

3. The first biasing member is a torsion spring, The second pressing member is positioned radially inward of the first biasing member. A reciprocating cutting tool according to claim 1 or 2, characterized by the features described above.

4. The aforementioned blade attachment / detachment section is equipped with a sleeve, The sleeve is rotatable about the direction of the reciprocating motion, The first pressing member and the first biasing member are arranged radially inward of the sleeve. A reciprocating cutting tool according to any one of claims 1 to 3.

5. The sleeve has a cam surface on its inner surface, The first pressing member moves in accordance with the rotation of the sleeve by following the cam surface. The reciprocating cutting tool according to feature 4.

6. The second pressing member extends in the direction of the reciprocating motion and has an engaging portion. The sleeve has an engaging portion, The rotation of the sleeve is stopped when the engaging portion engages with the engaged portion. The reciprocating cutting tool according to claim 4 or 5, characterized by the features described above.

7. When the engaging portion engages with the engaged portion, the sleeve allows the first pressing member to move to a position where it does not press the blade. When the engagement of the engaging portion with the engaged portion is released, the sleeve moves the first pressing member to a position that presses the blade. The reciprocating cutting tool described in Feature 6.

8. The second pressing member has a pressing portion and a tongue portion, The tongue portion integrally connects the engaging portion and the pressing portion. When the pressing portion is pressed by the blade, the engaging portion moves and disengages from the engaged portion. The reciprocating cutting tool according to claim 6 or 7, characterized by the features described above.

9. The tongue portion and the pressing portion extend in the direction of the reciprocating motion. The tongue portion is offset in a direction perpendicular to the direction of the reciprocating motion with respect to the virtual center line of the pressing portion. The reciprocating cutting tool according to feature 8.

10. The blade attachment / detachment mechanism is designed to be reciprocating, The aforementioned blade attachment / detachment section is A first pressing member is movable in a direction approaching and moving away from the blade and is capable of pressing the blade, A first biasing member that biases the first pressing member, The blade is pressed by a second pressing member which is capable of pressing the blade in a direction different from the direction of pressing by the first pressing member, A second biasing member that biases the second pressing member, A sleeve that is rotatable about the direction of the aforementioned reciprocating motion, It has, The first pressing member and the first biasing member are arranged radially inward of the sleeve. The first pressing member moves in accordance with the rotation of the sleeve, The second pressing member extends in the direction of the reciprocating motion and has an engaging portion, a pressing portion, and a tongue portion. The sleeve has an engaging portion, When the engaging portion engages with the engaged portion, the rotation of the sleeve is stopped. The tongue portion integrally connects the engaging portion and the pressing portion. When the pressing portion is pressed by the blade, the engaging portion moves and disengages from the engaged portion. The tongue portion and the pressing portion extend in the direction of the reciprocating motion. The tongue portion is offset in a direction perpendicular to the direction of the reciprocating motion with respect to the virtual center line of the pressing portion. A reciprocating cutting tool characterized by the following features.

11. The virtual center line of the blade attached to the blade attachment / detachment portion in the extending direction is shifted toward the first pressing member in a direction perpendicular to the direction of reciprocating motion with respect to the virtual center line of the blade attachment / detachment portion in the extending direction. A reciprocating cutting tool according to any one of claims 1 to 10.

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