Work machine

Abstract

To inhibit deterioration of workability.SOLUTION: In a reciprocation mechanism 70 of an electric cutting machine 10, a joint part 74 connects a first eccentric shaft part 60A with a connecting rod 71 and connects the connecting rod 71 with a plunger 72. The joint part 74 connects the connecting rod 71 with the first eccentric shaft part 60A and a plunger 72 in a manner that enables the connecting rod 71 to rotate with an axial direction set to a vertical direction and guides the connecting rod 71 in a manner that enables the connecting rod 71 to rotate with the axial direction set to a horizontal direction. Thus, when rotational force whose axial direction is set to the horizontal direction is input to the joint part 74, the joint part 74 can allow the connecting rod 71 to rotate relative to the first eccentric shaft part 60A and the plunger 72. As the result, the structure can inhibit damage, etc. of the reciprocation mechanism 70. Therefore, the structure can inhibit deterioration of workability of the electric cutting machine 10.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a working machine.

Background Art

[0002] In working machines, there are those that perform work by reciprocating a predetermined part, and there are various reciprocating motion conversion mechanisms for this purpose. In the electric tool (working machine) described in Patent Document 1 below, the rotational motion of the motor is converted into a linear motion by a Scotch-yoke type motion conversion mechanism, and the plunger reciprocates in the front-rear direction. Specifically, the connecting piece rotates eccentrically about the vertical axis, and the motion is received by a pin guide integrated with the plunger, so that power is transmitted to the plunger in the front-rear direction. In the electric tool (working machine) described in Patent Document 2 below, the rotational motion of the motor is converted into a linear motion by a so-called connecting rod type motion conversion mechanism, and the piston reciprocates in the front-rear direction. Specifically, the lower end of the crankshaft with the vertical direction as the axial direction is provided so as to be integrally rotatable with the gear, and the crankshaft is arranged at a position eccentric with respect to the axis of the gear. Further, the rear end of the connecting rod extending in the front-rear direction is rotatably connected to the crankshaft, and the front end of the connecting rod is rotatably connected to the piston with the vertical direction as the axial direction. That is, the motion conversion mechanism is a so-called crank mechanism. Thereby, when the gear rotates by the driving force of the motor, the piston reciprocates in the front-rear direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, in the power tool using the motion conversion mechanism of Patent Document 2 described above, there is room for improvement in the following points. That is, for example, when a rotational force having an axial direction in the left - right direction is generated at the connecting portion between the connecting rod and the crankshaft due to a load generated during the operation of the power tool, there is a risk that the connecting portion may be damaged or deformed by this rotational force. If the connecting portion is damaged or the like, it becomes difficult to continue the work, and the workability may be reduced. Further, for example, in the motion conversion mechanism, in order to convert the rotational motion into a linear motion and reciprocate the piston in the front - rear direction, vibrations generated during the operation of the working machine may be transmitted to the operator or the like, and the workability may be reduced.

[0005] An object of the present invention is to provide a working machine capable of suppressing a reduction in workability in consideration of the above facts.

Means for Solving the Problems

[0006] One or more embodiments of the present invention include a motor, an eccentric portion that eccentrically rotates about an axis extending in a predetermined direction by driving of the motor, and a conversion mechanism that converts the rotational motion of the eccentric portion into a reciprocating motion. The conversion mechanism includes a connecting rod connected to the eccentric portion, a reciprocating portion connected to the connecting rod and reciprocating in a first intersecting direction intersecting the predetermined direction, a swing mechanism including a guide surface inclined with respect to the first intersecting direction for displacing one end of the reciprocating portion in the predetermined direction during the reciprocating movement of the reciprocating portion, and a joint portion. The joint portion rotatably connects the connecting rod to at least one of the eccentric portion and the reciprocating portion with the predetermined direction as the axial direction, and has a spherical sliding bearing structure that rotatably guides with the second intersecting direction intersecting the predetermined direction and the first intersecting direction as the axial direction, and is a working machine.

[0007] One or more embodiments of the present invention include a motor, an eccentric portion that eccentrically rotates about an axis extending in a predetermined direction by driving the motor, and a conversion mechanism that converts the rotational motion of the eccentric portion into a reciprocating motion. The conversion mechanism includes a connecting rod connected to the eccentric portion, a reciprocating movement portion connected to the connecting rod and extending in a first intersecting direction intersecting the predetermined direction and reciprocatingly moving in the first intersecting direction, and a swing mechanism including an inclined guide that is inclined with respect to the first intersecting direction because one end of the reciprocating movement portion is displaced in the predetermined direction during the reciprocating movement of the reciprocating movement portion, and a joint portion. The joint portion is a working machine that rotatably connects the connecting rod to at least one of the eccentric portion and the reciprocating movement portion with the predetermined direction as an axial direction and rotatably guides the connecting rod with a second intersecting direction intersecting the predetermined direction and the first intersecting direction as an axial direction.

[0008] One or more embodiments of the present invention are working machines in which the joint portion has a spherical sliding bearing structure.

[0009] One or more embodiments of the present invention are working machines in which the joint portion has a first joint member and a second joint member, and the spherical sliding bearing structure includes a convex spherical surface portion formed on the first joint member and a concave spherical surface portion formed on the second joint member and configured to be slidable on the convex spherical surface portion.

[0010] One or more embodiments of the present invention are working machines in which the joint portion has rolling members, and the connecting rod is rotatably connected to at least one of the eccentric portion and the reciprocating movement portion with the predetermined direction as an axial direction via the rolling members.

[0011] One or more embodiments of the present invention are such that the connecting rod and the reciprocating part are connected by the joint part, the reciprocating part is provided with a tool mounting part on which a tip tool is mounted, the reciprocating movement of the reciprocating part is guided by a swing mechanism, and when the reciprocating part reciprocates, the reciprocating part swings by the swing mechanism and the tool mounting part swings in the predetermined direction. It is a working machine.

[0012] One or more embodiments of the present invention are such that the reciprocating part extends in the first intersecting direction, the tool mounting part is provided at one end in the longitudinal direction of the reciprocating part, the connecting rod is connected to the other end in the longitudinal direction of the reciprocating part, and the swing mechanism includes a first guide part that guides the movement of the reciprocating part in the first intersecting direction, and a second guide part that is located at a position separated from the first guide part in the first intersecting direction and guides the movement of the reciprocating part in the first intersecting direction. When guiding the reciprocating part by the first guide part and the second guide part, the other end in the longitudinal direction of the reciprocating part is displaced to one side or the other side in the predetermined direction by the second guide part, and the first guide part supports the reciprocating part so as to be swingable. It is a working machine.

[0013] One or more embodiments of the present invention are such that a blade part is provided at one end in the predetermined direction of the tip tool mounted on the tool mounting part, the swing mechanism is configured to be switchable between a normal swing mode and a reverse swing mode, and in the normal swing mode, when the reciprocating part moves forward, the tool mounting part moves to one side in the first intersecting direction and the other side in the predetermined direction, and when the reciprocating part moves backward, the tool mounting part moves to the other side in the first intersecting direction and one side in the predetermined direction. In the reverse swing mode, when the reciprocating part moves forward, the tool mounting part moves to one side in the first intersecting direction and one side in the predetermined direction, and when the reciprocating part moves backward, the tool mounting part moves to the other side in the first intersecting direction and the other side in the predetermined direction. It is a working machine.

[0014] One or more embodiments of the present invention are work machines in which the connecting rod extends in the first intersecting direction, and the swing mechanism has a regulating member that regulates rotation about the longitudinal direction of the connecting rod as an axial direction.

[0015] One or more embodiments of the present invention are work machines in which the regulating member is provided on at least one of the connecting rod, the reciprocating portion, and the tool mounting portion.

[0016] One or more embodiments of the present invention are work machines in which the regulating member has a regulating portion that regulates rotation of the connecting rod by coming into contact therewith, and when viewed from the predetermined direction, the regulating portion is provided on both sides of the joint portion in the second intersecting direction.

[0017] One or more embodiments of the present invention include a motor having a predetermined direction as an axial direction, a rotating body that rotates about the predetermined direction as an axial direction by the driving force of the motor, an eccentric portion that is integrally rotatably provided on the rotating body and is disposed at a position eccentric with respect to the axis of the rotating body, and a conversion mechanism that converts the rotational motion of the eccentric portion that eccentrically rotates about the axis of the rotating body into a reciprocating motion. The conversion mechanism includes a connecting rod connected to the eccentric portion, a reciprocating portion that is connected to the connecting rod and reciprocates in a first intersecting direction that intersects the predetermined direction, and a joint portion. The joint portion is configured to rotatably connect the connecting rod to at least one of the eccentric portion and the reciprocating portion about the predetermined direction as an axial direction, and to rotatably guide about a second intersecting direction that intersects the predetermined direction and the first intersecting direction as an axial direction.

[0018] One or more embodiments of the present invention are work machines in which the motor is disposed on one side in the predetermined direction of the rotating body and the conversion mechanism, a vibration reduction mechanism is provided on the other side in the predetermined direction of the conversion mechanism, and at least a part of the reciprocating movement portion overlaps the vibration reduction mechanism when viewed from the predetermined direction, and the vibration reduction mechanism reduces vibration generated during the reciprocating movement of the reciprocating movement portion.

Advantages of the Invention

[0019] According to one or more embodiments of the present invention, a decrease in workability can be suppressed.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0021] Hereinafter, the electric cutter 10 as a working machine according to the present embodiment will be described with reference to the drawings. The arrows UP, FR, and RH appropriately shown in the drawings indicate the upper side, the front side, and the right side of the electric cutter 10, respectively. In the following description, when the up-down, front-back, and left-right directions are used for explanation, unless otherwise specified, they indicate the up-down direction, the front-back direction, and the left-right direction of the electric cutter 10. And the up-down direction corresponds to the predetermined direction of the present invention, the front-back direction corresponds to the first intersecting direction of the present invention, and the left-right direction corresponds to the second intersecting direction of the present invention.

[0022] The electric cutter 10 is configured as an electric tool for performing cutting work on a workpiece such as a pipe. As shown in FIGS. 1 and 2, the electric cutter 10 includes a housing 12 that constitutes the outer shell of the electric cutter 10, a case 30 housed and fixed within the housing 12, and a motor 40 assembled to the case 30. Further, the electric cutter 10 has a gear mechanism 50, a reciprocating mechanism 70 as a conversion mechanism, a swing mechanism 90, and a vibration reduction mechanism 110, which are housed within the case 30.

[0023] (Regarding the housing 12) As shown in FIG. 1, the housing 12 is formed in a substantially hollow column shape that extends in the front-rear direction as a whole. The housing 12 includes a front housing portion 12A that constitutes the front portion of the housing 12 and a handle housing portion 12B that constitutes the rear end portion of the housing 12. The front housing portion 12A extends in the front-rear direction, and the rear end portion of the front housing portion 12A is bent downward. The handle housing portion 12B extends in the vertical direction, and both the upper and lower end portions of the handle housing portion 12B in the vertical direction are bent forward and connected to the rear end portion of the front housing portion 12A. During cutting, the operator holds the handle housing portion 12B and performs the cutting operation.

[0024] A trigger 14 is provided on the upper end side portion of the handle housing portion 12B. The trigger 14 protrudes forward from the handle housing portion 12B and is configured to be operable to be pulled backward. A switch mechanism portion 16 is provided on the handle housing portion 12B behind the trigger 14. The switch mechanism portion 16 has a switch (not shown) that is operated by the trigger 14, and the switch is electrically connected to the controller 18. The controller 18 is provided at the vertical intermediate portion on the rear end side of the front housing portion 12A. Then, an output signal corresponding to the operation of the trigger 14 is output from the switch to the controller 18.

[0025] A battery 20 is detachably attached to the lower end portion of the handle housing portion 12B from the rear side. The battery 20 is electrically connected to the controller 18 and a motor 40 (described later), and power is supplied from the battery 20 to the controller 18 and the motor 40.

[0026] (Regarding the case 30) As shown in FIGS. 1 and 2, the case 30 is formed in a substantially rectangular box shape extending in the front-rear direction as a whole. The case 30 is housed in the upper part of the front housing portion 12A and is fixed to the housing 12. The rear part of the case 30 is open upward, and the opening is closed by the upper case cover 32. Further, the front part of the case 30 is open downward, and the opening is closed by the lower case cover 34. The upper case cover 32 and the lower case cover 34 are formed in a substantially rectangular plate shape with the vertical direction as the plate thickness direction and are fastened and fixed to the case 30.

[0027] At the bottom of the rear part of the case 30, a first insertion hole 30A for inserting a support shaft 52 described later is formed to penetrate vertically. The first insertion hole 30A is formed in a substantially stepped hole shape, and the diameter of the lower part of the first insertion hole 30A is set larger than the diameter of the upper part of the first insertion hole 30A. At the bottom of the case 30, a ball groove 30B for accommodating a rolling ball 57 described later is formed on the radially outer side of the first insertion hole 30A. The ball groove 30B is formed in a groove shape that is open upward and along the circumferential direction of the first insertion hole 30A, and is formed in an annular shape when viewed from above. At the bottom of the case 30, on the rear side of the first insertion hole 30A, a second insertion hole 30C through which a rotation shaft 41 described later is inserted is formed to penetrate vertically. The second insertion hole 30C is formed in a substantially stepped hole shape, and the diameter of the lower part of the second insertion hole 30C is set larger than the diameter of the upper part of the first insertion hole 30A.

[0028] At the front part of the upper wall of the case 30, a knob support cylinder portion 30D for supporting a knob 103 described later is formed. The knob support cylinder portion 30D is formed in a substantially cylindrical shape with the vertical direction as the axial direction and protrudes upward from the case 30. On the rear wall of the case 30, a placement portion 30E for placing a vibration reduction mechanism 110 described later is formed, and the placement portion 30E is arranged at a position one step lower than the opening of the case 30. The placement portion 30E is also formed at the rear parts of the left and right side walls of the case 30.

[0029] (Regarding the motor 40) The motor 40 is a brushless motor and is disposed below the rear end portion of the case 30. The motor 40 has a rotating shaft 41. The rotating shaft 41 extends in the vertical direction, and a pinion gear 42 is integrally provided at the upper end portion of the rotating shaft 41. The upper end side portion of the rotating shaft 41 passes through the second insertion hole 30C of the case 30, and the pinion gear 42 of the rotating shaft 41 is disposed inside the rear portion of the case 30. The upper end side portion of the rotating shaft 41 is rotatably supported by a motor bearing 43. The motor bearing 43 is disposed inside the lower portion of the second insertion hole 30C and is fixed to the case 30. The lower end portion of the rotating shaft 41 is rotatably supported by a motor bearing 44, and the motor bearing 44 is fixed to a bearing holder 45 assembled to the case 30.

[0030] (Regarding the gear mechanism 50) The gear mechanism 50 is mainly composed of a transmission gear 51 as a rotating body. The transmission gear 51 is formed in a substantially disk shape with the vertical direction as the thickness direction. The transmission gear 51 is accommodated in the case 30 on the front side of the pinion gear 42 on the rotating shaft 41 and meshes with the pinion gear 42. A support shaft 52 with the vertical direction as the axial direction is provided at the central portion of the transmission gear 51. The support shaft 52 projects downward from the transmission gear 51 and passes through the inside of the first insertion hole 30A. The lower end portion of the support shaft 52 is rotatably supported by a bearing 53. The bearing 53 is accommodated in the lower portion of the first insertion hole 30A and is fixed to the case 30. A shaft bolt 54 is screwed onto the lower end portion of the support shaft 52, and the shaft bolt 54 is fixed to the inner ring of the bearing 53 via a washer 36.

[0031] A thrust bearing 55 is provided below the transmission gear 51. The thrust bearing 55 includes a ring base 56 and a plurality of rolling balls 57. The ring base 56 is formed in a substantially annular shape and, in a cross section viewed from its longitudinal direction, is formed in a substantially U-shaped plate shape that is open upward. The ring base 56 is accommodated in the ball groove 30B and is supported from below by a rubber washer 58. The rubber washer 58 is made of an elastic material such as rubber and is formed in a substantially annular plate shape. The rubber washer 58 is disposed between the bottom surface of the ball groove 30B and the thrust bearing 55. The plurality of rolling balls 57 are placed on the upper side of the lower wall of the ring base 56 and are arranged side by side in the circumferential direction of the ball groove 30B. The upper end portion of the rolling ball 57 protrudes above the bottom surface of the case 30 and is disposed adjacent to the lower side of the transmission gear 51.

[0032] A crankshaft 60 is provided on the transmission gear 51 so as to be integrally rotatable. The crankshaft 60 is formed in a substantially crank shape in a side view. Specifically, the crankshaft 60 includes a first eccentric shaft portion 60A as an eccentric portion extending in the vertical direction, a shaft connecting portion 60B extending forward from the upper end portion of the first eccentric shaft portion 60A, and a second eccentric shaft portion 60C extending upward from the tip end portion of the shaft connecting portion 60B. The first eccentric shaft portion 60A is formed in a substantially cylindrical shape with the vertical direction as the axial direction, is disposed at a position eccentric with respect to the axis AL of the transmission gear 51, and protrudes upward from the transmission gear 51. The second eccentric shaft portion 60C is formed in a substantially cylindrical shape with the vertical direction as the axial direction, similar to the first eccentric shaft portion 60A, and is disposed at a position opposite to the first eccentric shaft portion 60A with the support shaft 52 interposed therebetween and eccentric with respect to the support shaft 52. Specifically, the first eccentric shaft portion 60A and the second eccentric shaft portion 60C are disposed 180 degrees apart in the circumferential direction of the transmission gear 51. A cylindrical sleeve 62 is rotatably externally inserted on the second eccentric shaft portion 60C.

[0033] (Regarding the reciprocating mechanism 70) The reciprocating mechanism 70 is housed in the case 30 above the gear mechanism 50. The reciprocating mechanism 70 includes a connecting rod 71, a plunger 72 as a reciprocating moving part, and a joint part 74. The reciprocating mechanism 70 is connected to the first eccentric shaft part 60A, and is configured as a mechanism that converts the rotational motion of the first eccentric shaft part 60A, which eccentrically rotates about the axis AL of the transmission gear 51 by the drive of the motor 40, into a reciprocating motion, and reciprocates the plunger 72 in the front-rear direction.

[0034] As shown in FIGS. 2 and 3, the connecting rod 71 is formed in a substantially long plate shape with the vertical direction as the plate thickness direction and the front-rear direction as the longitudinal direction. Circular joint holes 71A are respectively formed through the front end portion and the rear end portion of the connecting rod 71. The joint parts 74 described later are respectively assembled in the joint holes 71A. Then, by the joint part 74, the rear end portion of the connecting rod 71 is connected to the upper end side portion of the first eccentric shaft part 60A of the crankshaft 60.

[0035] As shown in FIG. 2, the plunger 72 is formed in a substantially bottomed cylindrical shape that is open to the rear side. The plunger 72 is guided by a swing mechanism 90, which will be described later, so as to be movable in the front-rear direction. A plunger connecting portion 72A is provided at the rear end portion of the plunger 72. When viewed from the left-right direction, the plunger connecting portion 72A is formed in a U shape that is open to the rear side. As also shown in FIG. 3, a plunger connecting shaft 73 having the vertical direction as its axial direction is bridged across the plunger connecting portion 72A. The upper end portion of the plunger connecting shaft 73 protrudes above the plunger connecting portion 72A, and a flange 73A that projects radially outward is formed at the upper end portion of the plunger connecting shaft 73. The lower end portion of the plunger connecting shaft 73 protrudes below the plunger connecting portion 72A, and a fixing screw SC is screwed into the lower end portion of the plunger connecting shaft 73. By means of the fixing screw SC, a regulating member 108, which will be described later, is fixed to the lower surface of the plunger connecting portion 72A. And the front end portion of the connecting rod 71 is disposed within the plunger connecting portion 72A and is connected to the plunger connecting shaft 73 (the rear end portion of the plunger 72) by a joint portion 74, which will be described later.

[0036] A blade mounting mechanism 80 as a tool mounting portion is provided at the front end portion of the plunger 72. A blade 82 as a tip tool is mounted on the blade mounting mechanism 80. The blade 82 is formed in a substantially long plate shape with the left-right direction as the plate thickness direction and extending in the front-rear direction, and the rear end portion of the blade 82 is mounted on the blade mounting mechanism 80. A blade portion 82A is formed at the lower end portion of the blade 82, and the blade portion 82A is formed over the entire longitudinal direction of the blade 82.

[0037] (Regarding the joint portion 74) The joint portion 74 is provided between the rear end portion of the connecting rod 71 and the first eccentric shaft portion 60A of the crankshaft 60, and connects the connecting rod 71 and the first eccentric shaft portion 60A. Further, the joint portion 74 is provided between the front end portion of the connecting rod 71 and the plunger connecting shaft 73, and connects the connecting rod 71 and the plunger 72. Hereinafter, the configuration of the joint portion 74 will be described using the front joint portion 74.

[0038] As shown in FIG. 4, the joint portion 74 is formed in a substantially cylindrical shape with the vertical direction as the axial direction as a whole. The joint portion 74 includes a needle bearing 75 as a rolling member that constitutes the radially inner portion of the joint portion 74, an inner sleeve 76 as a first joint member that constitutes the radially intermediate portion of the joint portion 74, and an outer sleeve 77 as a second joint member that constitutes the radially outer portion of the joint portion 74.

[0039] The inner sleeve 76 is formed in a substantially cylindrical shape with the vertical direction as the axial direction. The needle bearing 75 is fitted into the inner sleeve 76, and the needle bearing 75 and the inner sleeve 76 are unitized. Then, the needle bearing 75 is externally inserted into the plunger connecting shaft 73 and connected to the plunger connecting shaft 73. A convex spherical surface portion 76A is formed on the outer peripheral surface of the inner sleeve 76. The convex spherical surface portion 76A coincides with a part of a spherical surface whose center is located on the axis of the plunger connecting shaft 73.

[0040] The outer sleeve 77 is formed in a substantially cylindrical shape with the vertical direction as the axial direction. A concave spherical surface portion 77A is formed on the inner peripheral surface of the outer sleeve 77. The concave spherical surface portion 77A is formed as a spherical surface corresponding to the convex spherical surface portion 76A and is configured to be slidable with respect to the convex spherical surface portion 76A. That is, the joint portion 74 has a spherical sliding bearing structure S. The outer sleeve 77 is fitted into the front joint hole 71A in the connecting rod 71 and is connected to the front end portion of the connecting rod 71. As described above, by the joint portion 74, the connecting rod 71 is rotatably connected to the plunger connecting shaft 73 (the rear end portion of the plunger 72) with the vertical direction, the front-rear direction, and the left-right direction as the axial directions. That is, when the connecting rod 71 rotates relative to the plunger 72 with any of the vertical direction, the front-rear direction, and the left-right direction as the axial direction, the rotation of the connecting rod 71 is guided by the joint portion 74.

[0041] The rear end portion of the connecting rod 71 is also rotatably connected to the first eccentric shaft portion 60A by the joint portion 74 with the vertical direction, the front-rear direction, and the left-right direction as the axial directions. Thus, when the transmission gear 51 rotates by the drive of the motor 40 and the first eccentric shaft portion 60A eccentrically rotates about the axis AL of the transmission gear 51, the plunger 72 connected to the first eccentric shaft portion 60A by the connecting rod 71 reciprocates in the front-rear direction. Therefore, when the reciprocating mechanism 70 operates, the blade 82 reciprocates in the front-rear direction together with the plunger 72. Specifically, the blade 82 and the plunger 72 reciprocate between the rear dead center position (the position shown in FIG. 8(A)) and the front dead center position (the position shown in FIG. 8(B)) moved forward from the rear dead center position.

[0042] (Regarding the swing mechanism 90) As shown in FIG. 2, the swing mechanism 90 is configured as a mechanism for guiding the reciprocating movement of the plunger 72 in the front-rear direction. Further, the swing mechanism 90 is also configured as a mechanism for swinging the blade mounting mechanism 80 (the front end portion of the plunger 72) in the vertical direction when the plunger 72 reciprocates in the front-rear direction. Specifically, the swing mechanism 90 is configured to be switchable to any one of a non-swing mode, a forward swing mode, and a reverse swing mode. In the non-swing mode of the swing mechanism 90, the blade mounting mechanism 80 does not swing vertically but reciprocates along the front-rear direction. In the forward swing mode of the swing mechanism 90, when the plunger 72 moves forward (during the forward stroke), the blade mounting mechanism 80 moves to the front side and the upper side, and when the plunger 72 moves backward (during the return stroke), the blade mounting mechanism 80 moves to the rear side and the lower side. In the reverse swing mode of the swing mechanism 90, when the plunger 72 moves forward, the blade mounting mechanism 80 moves to the front side and the lower side, and when the plunger 72 moves backward, the blade mounting mechanism 80 moves to the rear side and the upper side. The swing mechanism 90 is a mechanism for causing the blade to bite into the workpiece during the retraction of the blade 82, and the reverse swing mode is a mode that is particularly effective when the blade of the blade 82 is mounted upward.

[0043] The swing mechanism 90 includes a support guide mechanism portion 91 as a first guide portion, a rear guide mechanism portion 95 as a second guide portion, a mode switching mechanism portion 100, and a regulating member 108.

[0044] As shown in FIGS. 2 and 5, the support guide mechanism portion 91 mainly includes a pair of upper and lower support rollers 92. The support rollers 92 are housed inside the front end portion of the case 30 and are arranged adjacent to both the upper and lower sides of the middle portion in the front-rear direction of the plunger 72. The upper support roller 92 is rotatably supported by an upper roller shaft 93 having the left-right direction as the axial direction. Both end portions of the upper roller shaft 93 are bridged over the left and right side walls of the case 30 and are fixed to a shaft holder 89 housed inside the case 30. The lower support roller 92 is rotatably supported by a lower roller shaft 94 having the left-right direction as the axial direction, and both end portions of the lower roller shaft 94 are bridged over the shaft holder 89. A roller groove 92A is formed on the outer peripheral surface of the support roller 92. The roller groove 92A is formed in a substantially arc shape that opens radially outward when viewed from the circumferential direction of the support roller 92 and is adapted to be in close contact with the outer peripheral surface of the plunger 72. Thereby, the middle portion in the front-rear direction of the plunger 72 is supported from both the upper and lower sides by the pair of upper and lower support rollers 92, and the movement of the plunger 72 in the front-rear direction is guided.

[0045] As shown in FIGS. 2 and 6, the rear guide mechanism portion 95 has a guide member 96 and a pair of left and right rolling rollers 97. The rear guide mechanism portion 95 is located at a position spaced apart from the support guide mechanism portion 91 in the front-rear direction. The guide member 96 is formed in a cylindrical shape with the front-rear direction as the axial direction and is housed in the middle portion in the front-rear direction of the case 30. The middle portion in the front-rear direction at the upper end of the guide member 96 is rotatably supported by a guide support shaft 98 having the left-right direction as the axial direction, and the guide support shaft 98 is bridged across the left and right side walls of the case 30. In the non-swing mode of the swing mechanism 90, the guide member 96 is located at the initial position (the position shown in FIG. 2). In the forward swing mode of the swing mechanism 90, the guide member 96 is rotated by a mode switching mechanism portion 100 described later to the forward swing mode position (the position shown in FIGS. 9(A) and (B)) rotated clockwise from the initial position when viewed from the right side. In the reverse swing mode of the swing mechanism 90, the guide member 96 is rotated by the mode switching mechanism portion 100 described later to the reverse swing mode position (the position shown in FIGS. 10(A) and (B)) rotated counterclockwise from the initial position when viewed from the right side.

[0046] The interior of the guide member 96 is a guide hole 96A, which is formed in a substantially cross shape when viewed from the front side. The rear end side portion of the plunger 72 is inserted into the guide hole 96A, and the plunger connecting portion 72A of the plunger 72 is located on the rear side of the guide member 96. The left and right side portions of the guide hole 96A are guide grooves 96B (guide portions), and the guide grooves 96B are formed in a concave shape that opens inward in the left - right direction and penetrates in the front - rear direction. In the initial position of the guide member 96, the guide grooves 96B extend along the front - rear direction. The guide grooves 96B have guide surfaces in contact with and guiding the rolling rollers 97 at the lower and upper parts. The rolling roller 97 is guided by contacting the lower or upper part according to the direction of the load applied to the blade 82. Specifically, when an upward load is applied to the blade 82 from below, with the support roller 92 as a fulcrum, the rear end of the plunger 72 moves downward, and thereby the rolling roller 97 contacts and is guided by the lower guide surface of the guide groove 96B. When the direction of the load on the blade 82 is reversed, the rolling roller 97 contacts and is guided by the upper guide surface of the guide groove 96B.

[0047] A pair of left - right rolling rollers 97 are arranged outside the left - right direction of the rear end side portion of the plunger 72. A roller shaft 99 for supporting the rolling roller 97 is fixed to the plunger 72. The roller shaft 99 is arranged with the left - right direction as the axial direction and penetrates the plunger 72, and both axial ends of the roller shaft 99 protrude from the plunger 72 to both sides in the left - right direction. And the rolling roller 97 is rotatably supported at both axial ends of the roller shaft 99. The rolling roller 97 is arranged inside the rear end portion of the guide groove 96B at the rear dead center position of the plunger 72. When the plunger 72 reciprocates in the front - rear direction, the front - rear movement of the rear end side portion of the plunger 72 is guided by the rolling roller 97 and the guide groove 96B.

[0048] Accordingly, in the non-swing mode of the swing mechanism 90, the rear end portion of the plunger 72 reciprocates along the front-rear direction. For this reason, when the plunger 72 reciprocates in the front-rear direction in the non-swing mode of the swing mechanism 90, the blade mounting mechanism 80 is configured to reciprocate in the front-rear direction together with the plunger 72 (see FIGS. 8(A) and (B)).

[0049] On the other hand, in the forward swing mode (reverse swing mode) of the swing mechanism 90, when the plunger 72 moves forward, the rear end portion of the plunger 72 is displaced downward (upward), and when the plunger 72 moves backward, the rear end portion of the plunger 72 is displaced upward (downward). At this time, the guide groove 96B (guide surface) is inclined with respect to the front-rear direction. Also, as described above, the plunger 72 is supported from both sides in the vertical direction by a pair of upper and lower support rollers 92. Accordingly, when the plunger 72 reciprocates in the front-rear direction in the forward swing mode of the swing mechanism 90, the plunger 72 swings with the pair of upper and lower support rollers 92 as a fulcrum, and the blade mounting mechanism 80 is configured to swing in the vertical direction (see FIGS. 9(A) and (B)). Further, when the plunger 72 reciprocates in the front-rear direction in the reverse swing mode of the swing mechanism 90, the plunger 72 swings with the pair of upper and lower support rollers 92 as a fulcrum, and the blade mounting mechanism 80 is configured to swing in the vertical direction (see FIGS. 10(A) and (B)).

[0050] As shown in FIGS. 6 and 7, the mode switching mechanism unit 100 includes a guide plate 101, a pair of front and rear switching balls 102 (see FIG. 2), a knob 103, and a regulating member 107.

[0051] The guide plate 101 is bent into a substantially concave shape that opens downward when viewed from the front side. The guide plate 101 is integrally and rotatably assembled to the guide member 96 so as to cover the guide member 96 from above and laterally outward in the left and right directions. A ball groove 101A is formed in the central portion of the guide plate 101 in the left and right direction. The ball groove 101A is formed in a groove shape that opens upward and extends in the front-rear direction, and is formed in a substantially arc shape that opens upward when viewed from its longitudinal direction. Switching balls 102 are respectively placed at the front end portion and the rear end portion of the ball groove 101A, and the lower end portion of the switching ball 102 is disposed within the ball groove 101A.

[0052] The knob 103 is formed as a substantially columnar shape with the vertical direction as the thickness direction as a whole. The knob 103 includes a knob body 104 that constitutes the upper portion of the knob 103 and a cam member 105 that constitutes the lower portion of the knob 103, and the knob body 104 and the cam member 105 are fastened and fixed to each other. Further, a disk-shaped knob plate 106 is provided between the knob body 104 and the cam member 105, and the knob plate 106 is sandwiched vertically by the knob body 104 and the cam member 105.

[0053] The knob 103 is disposed within the knob support cylinder portion 30D of the case 30 above the guide plate 101, and is rotatably supported by the knob support cylinder portion 30D with the vertical direction as the axial direction. A ring-shaped ring plate 38 is provided on the inner peripheral portion of the knob support cylinder portion 30D. The ring plate 38 is disposed between the knob plate 106 and the knob body 104, and the vertical movement of the knob 103 is restricted by the ring plate 38.

[0054] On the upper surface of the knob body 104, a knob portion 104A extending in the front-rear direction is formed. And the knob portion 104A of the knob 103 is operably exposed from the upper part of the housing 12. On the outer peripheral portion of the knob body 104, a knob flange 104B protruding radially outward is formed, and the knob flange 104B is located above the knob support cylinder portion 30D. On the knob flange 104B, a plurality (eight locations in the present embodiment) of regulating grooves 104C are formed penetrating in the vertical direction, and the regulating grooves 104C are formed in a substantially semicircular shape opened radially outward of the knob 103 in plan view. The regulating grooves 104C are arranged at equal intervals in the circumferential direction of the knob flange 104B.

[0055] On the outer peripheral portion of the lower surface of the cam member 105, a cam surface 105A is formed, and the cam surface 105A extends in the circumferential direction of the cam member 105 and is formed over the entire circumference. On the cam surface 105A, a cam groove 105B opened downward is formed. The upper end portion of the switching ball 102 is inserted into the cam groove 105B. And in the non-swing mode of the swing mechanism 90, the guide member 96 is held at the initial position by the switching ball 102 and the guide plate 101. Also, in plan view, by rotating the knob 103 clockwise by 90 degrees, the guide member 96 is arranged at the positive swing mode position from the initial position, and the vertical position of the cam surface 105A is set so that the swing mechanism 90 switches from the non-swing mode to the positive swing mode. Further, in plan view, by rotating the knob 103 counterclockwise by 90 degrees, the guide member 96 is arranged at the reverse swing mode position from the initial position, and the vertical position of the cam surface 105A is set so that the swing mechanism 90 switches from the non-swing mode to the reverse swing mode. In the positive swing mode, the guide groove 96B (the guide surface thereof) has an inclination angle such that it goes downward as it advances forward, and in the reverse swing mode, the guide groove 96B (the guide surface thereof) has an inclination angle such that it goes upward as it advances forward.

[0056] The regulating member 107 is a leaf spring and is formed in a substantially long plate shape with the radial direction of the knob 103 as the plate thickness direction and the circumferential direction of the knob 103 as the longitudinal direction. Specifically, the regulating member 107 is disposed on the front side of the knob 103 and is formed in a substantially C-shaped configuration that is open to the rear side in plan view. A fixing portion 107A bent forward is formed at the front end portion of the regulating member 107, and the fixing portion 107A is fastened and fixed to the case 30. Regulation engaging portions 107B are provided at both longitudinal ends of the regulating member 107, respectively. The regulation engaging portion 107B is bent into a substantially C-shaped configuration that is open outward in the left-right direction in plan view. The lower end portion of the regulation engaging portion 107B is connected to both longitudinal ends of the regulating member 107, and the upper end portion of the regulation engaging portion 107B is disposed in the regulation groove 104C of the knob 103. Thereby, the rotation of the knob 103 is restricted by the regulating member 107. When the knob 103 is rotated, the regulating member 107 elastically deforms outward in the left-right direction, and the regulation engaging portion 107B disengages from the regulation groove 104C and slides on the outer peripheral portion of the knob flange 104B. Further, the regulation engaging portion 107B engages again with the adjacent regulation groove 104C, thereby providing a regulation feeling (click feeling) to the knob 103.

[0057] As shown in FIGS. 3 and 4, the restricting member 108 is assembled to the plunger connecting portion 72A of the plunger 72 and is configured as a member that restricts rotation about the longitudinal direction (its own longitudinal direction) of the connecting rod 71. The restricting member 108 is a leaf spring and is formed in a substantially inverted hat shape that is open upward when viewed from the front side. Specifically, the restricting member 108 has a bottom wall 108A, a pair of side walls 108B extending upward from both left and right ends of the bottom wall 108A, and a pair of top walls 108C extending outward in the left-right direction from the upper end portions of the side walls 108B. The bottom wall 108A is disposed adjacent to the lower side of the plunger connecting portion 72A in the plunger 72 and is fixed to the plunger connecting portion 72A by a fixing screw SC. The pair of top walls 108C are disposed outside the left and right sides of the joint portion 74 and are located below the outer ends in the left-right direction of the rear end portion of the connecting rod 71. A restricting portion 108D that bulges upward is formed at the middle portion in the front-rear direction of the top wall 108C, and the restricting portion 108D is curved in a substantially C shape that is open downward when viewed from the left-right direction. The restricting portion 108D is disposed adjacent to the lower side of the connecting rod 71. Thereby, when the lower surface of the connecting rod 71 abuts against the restricting portion 108D, rotation of the connecting rod 71 about its longitudinal direction as the axial direction is restricted.

[0058] (Regarding the vibration reduction mechanism 110) As shown in FIGS. 2 and 7, the vibration reduction mechanism 110 is housed inside the upper end portion of the rear portion of the case 30 above the reciprocating mechanism 70. Specifically, in a plan view, at least a part of the connecting rod 71 and the plunger 72 overlaps the vibration reduction mechanism 110 in a plan view. The vibration reduction mechanism 110 includes a pair of left and right base members 111, a pair of left and right guide members 112, and a counterweight 113.

[0059] The base member 111 extends in the front-rear direction and is formed in a substantially L-shaped plate form when viewed from the front-rear direction, and is respectively disposed on the inner sides in the left-right direction of the left and right side walls of the case 30. Specifically, the base member 111 has a side wall extending in the vertical direction and a lower wall extending inward in the left-right direction from the lower end of the side wall. And the base member 111 is placed on the placement portion 30E of the case 30 and assembled to the case 30.

[0060] The pair of left and right guide members 112 extend in the front-rear direction as well as the base member 111 and are formed in a substantially L-shaped plate form when viewed from the front-rear direction. And the guide member 112 is placed on the lower wall of the base member 111 and is located on the inner side in the left-right direction of the side wall of the base member 111.

[0061] The counterweight 113 is formed in a substantially rectangular plate form with the vertical direction as the plate thickness direction and the front-rear direction as the longitudinal direction as a whole. The counterweight 113 is composed of a plurality of plate members, and these plate members are attached to each other. The counterweight 113 is disposed on the inner sides in the left and right of the side wall of the guide member 112.

[0062] On the left and right side surfaces of the counterweight 113, a pair of front and rear first ball groove portions 113A are respectively formed. The first ball groove portion 113A extends in the front-rear direction and is open to the outer side and the lower side in the left-right direction. And the counterweight 113 is rollably supported by a plurality (three in this embodiment) of first balls 114 disposed between the first ball groove portion 113A and the guide member 112. Thereby, the counterweight 113 is configured to be slidable in the front-rear direction.

[0063] Further, on the upper surface of the counterweight 113, a pair of front and rear second ball groove portions 113B are formed at the center in the left-right direction. The second ball groove portions 113B extend in the front-rear direction and are formed in a concave shape that opens upward in a cross-sectional view seen from the front-rear direction. A plurality (three in this embodiment) of second balls 115 are arranged in the second ball groove portions 113B, and the second balls 115 are in contact with the lower surface of the upper case cover 32 and the inner peripheral surface of the second ball groove portions 113B. As a result, the counterweight 113 is supported by rolling on the second balls 115.

[0064] A pair of front and rear connecting pieces 113C are provided at the middle portion of the counterweight 113 in the front-rear direction. The connecting pieces 113C are formed in a substantially rectangular plate shape that extends in the left-right direction with the front-rear direction as the plate thickness direction and protrude downward from the counterweight 113. The upper end portion of the second eccentric shaft portion 60C (sleeve 62) of the crankshaft 60 is disposed between the pair of front and rear connecting pieces 113C so as to be relatively movable in the left-right direction and engageable in the front-rear direction. As a result, when the transmission gear 51 rotates, the counterweight 113 reciprocates in the front-rear direction. Specifically, when the transmission gear 51 rotates, the counterweight 113 reciprocates in the front-rear direction in a reverse phase to the plunger 72.

[0065] (Function and effect) Next, the operation and effects of the electric cutting machine 10 of the present embodiment will be described.

[0066] In the cutting process of the electric cutting machine 10 configured as described above, when the operator pulls the trigger 14, the controller 18 drives the motor 40. As a result, the transmission gear 51 meshed with the pinion gear 42 of the motor 40 rotates, and the first eccentric shaft portion 60A of the crankshaft 60 eccentrically rotates around the axis AL of the transmission gear 51. Therefore, the reciprocating mechanism 70 operates, and the plunger 72 of the reciprocating mechanism 70 reciprocates along the front-rear direction together with the blade 82 (see FIGS. 8(A) and 8(B)). Therefore, the cutting process is performed on the workpiece.

[0067] Further, when the crankshaft 60 rotates, the counterweight 113 connected to the second eccentric shaft portion 60C of the crankshaft 60 reciprocates in the front-rear direction. Since the first eccentric shaft portion 60A and the second eccentric shaft portion 60C are separated by 180 degrees in the circumferential direction of the transmission gear 51, the reciprocating movement of the counterweight 113 in the front-rear direction is out of phase with the reciprocating movement of the plunger 72 and the blade 82 in the front-rear direction. Thereby, the vibration reduction mechanism 110 acts as a dynamic vibration absorber, and the vibration generated by the reciprocating movement of the plunger 72 and the blade 82 is reduced by the vibration reduction mechanism 110.

[0068] Further, when the blade 82 is swung to perform cutting, an operator rotates the knob 103 of the mode switching mechanism unit 100 to switch the swing mechanism 90 from the non-swing mode to the forward swing mode or the reverse swing mode. Specifically, in a plan view, by rotating the knob 103 clockwise (counterclockwise), the guide member 96 of the rear guide mechanism unit 95 rotates from the initial position to the forward swing mode position (reverse swing mode position), and the swing mechanism 90 transitions to the forward swing mode (reverse swing mode).

[0069] As shown in FIGS. 9(A) and (B), in the forward swing mode of the swing mechanism 90, when the plunger 72 moves forward, the rear end portion of the plunger 72 moves obliquely downward to the front side by the rear guide mechanism unit 95, so that the plunger 72 swings with the support guide mechanism unit 91 as a fulcrum, and the front end portion (blade 82) of the plunger 72 moves obliquely upward to the front side. On the other hand, in the forward swing mode of the swing mechanism 90, when the plunger 72 moves backward, the rear end portion of the plunger 72 moves obliquely upward to the rear side by the rear guide mechanism unit 95, so that the plunger 72 swings with the support guide mechanism unit 91 as a fulcrum, and the front end portion (blade 82) of the plunger 72 moves obliquely downward to the rear side. Thereby, the cutting process can be performed on the workpiece with the blade 82 being swung.

[0070] As shown in FIGS. 10(A) and 10(B), in the reverse swing mode of the swing mechanism 90, when the plunger 72 moves forward, the rear end portion of the plunger 72 is moved obliquely upward to the front by the rear guide mechanism portion 95, so that the plunger 72 swings with the support guide mechanism portion 91 as a fulcrum, and the front end portion (blade 82) of the plunger 72 moves obliquely downward to the front. On the other hand, in the reverse swing mode of the swing mechanism 90, when the plunger 72 moves backward, the rear end portion of the plunger 72 is moved obliquely downward to the rear by the rear guide mechanism portion 95, so that the plunger 72 swings with the support guide mechanism portion 91 as a fulcrum, and the front end portion (blade 82) of the plunger 72 moves obliquely upward to the rear. Thereby, the cutting process can be performed on the workpiece in a state where the blade 82 is swung.

[0071] Here, in the reciprocating mechanism 70 that converts the rotational motion of the first eccentric shaft portion 60A that eccentrically rotates about the axis AL into the reciprocating motion in the front-rear direction of the plunger 72, a rotational force having the left-right direction as the axial direction may be generated at the connecting portion of the reciprocating mechanism 70 due to the load generated during the cutting process of the electric cutting machine 10. Specifically, a rotational force having the left-right direction as the axial direction may be generated at the connecting portion between the connecting rod 71 and the first eccentric shaft portion 60A and at the connecting portion between the connecting rod 71 and the plunger 72. At this time, if the connecting portion is damaged or the like, the workability of the electric cutting machine 10 may be reduced.

[0072] Here, in the reciprocating mechanism 70 of the electric cutting machine 10, the joint portion 74 connects the first eccentric shaft portion 60A and the connecting rod 71, and also connects the connecting rod 71 and the plunger 72. Further, the joint portion 74 rotatably connects the connecting rod 71 to the first eccentric shaft portion 60A and the plunger 72 with the vertical direction as the axial direction, and rotatably guides it with the horizontal direction as the axial direction. Thus, if a rotational force with the horizontal direction as the axial direction is input to the joint portion 74, the joint portion 74 can relatively rotate the connecting rod 71 with respect to the first eccentric shaft portion 60A and the plunger 72. As a result, damage or the like of the reciprocating mechanism 70 can be suppressed. Therefore, a decrease in the workability of the electric cutting machine 10 can be suppressed.

[0073] Further, the joint portion 74 has a spherical sliding bearing structure S. Specifically, a convex spherical surface portion 76A is formed on the outer peripheral surface of the inner sleeve 76, and a concave spherical surface portion 77A on which the convex spherical surface portion 76A slides is formed on the inner peripheral surface of the outer sleeve 77. Also, a needle bearing 75 with the vertical direction as the axial direction is provided inside the inner sleeve 76. Thereby, with a simple configuration, the connecting rod 71 and the first eccentric shaft portion 60A (plunger 72) can be rotatably connected with the vertical direction as the axial direction and rotatably connected with the horizontal direction as the axial direction.

[0074] Also, the reciprocating movement of the plunger 72 in the front-rear direction is guided by the swing mechanism 90. When the plunger 72 reciprocates in the front-rear direction, the swing mechanism 90 causes the plunger 72 to swing, and the blade mounting mechanism 80 (blade 82) swings up and down. Thereby, the workpiece can be efficiently cut by the blade 82 that swings up and down.

[0075] Further, the swing mechanism 90 includes a support guide mechanism portion 91 that guides the forward and backward movement of the plunger 72 (particularly the front portion thereof), and a rear guide mechanism portion 95 that guides the forward and backward movement of the plunger 72 (particularly the rear portion thereof). When guiding the reciprocating movement of the plunger 72 in the forward and backward direction by the support guide mechanism portion 91 and the rear guide mechanism portion 95, the rear end side portion of the plunger 72 is displaced upward or downward by the rear guide mechanism portion 95, and the plunger 72 swings about the support guide mechanism portion 91 as a fulcrum. Specifically, a rolling roller 97 is provided on the rear end side portion of the plunger 72, and the rolling roller 97 is guided by a guide groove 96B of a guide member 96. When the plunger 72 reciprocates, the rear end side portion of the plunger 72 is displaced upward or downward by the guide member 96 and the rolling roller 97. Further, the front portion of the plunger 72 is supported by a pair of upper and lower support rollers 92. Therefore, when the plunger 72 reciprocates, the plunger 72 swings about the pair of support rollers 92 as a fulcrum. In other words, when the plunger 72 reciprocates, the plunger 72 is swingably supported by the support rollers 92. As described above, the blade 82 can be swung with a simple configuration.

[0076] Also, as described above, the joint portion 74 connects the connecting rod 71, the first eccentric shaft portion 60A, and the plunger 72 with the left - right direction as the axial direction. Thereby, in the forward swing mode or the reverse swing mode of the swing mechanism 90, the power of the motor 40 can be efficiently transmitted to the plunger 72 by the joint portion 74, and the plunger 72 can be swung well. That is, in the forward swing mode (reverse swing mode) of the swing mechanism 90, compared with the non - swing mode, since the joint portion 74 is arranged at a position slightly displaced upward (downward), the postures of the plunger 72 and the connecting rod 71 are changed so as to be slightly inclined. For this reason, when the reciprocating mechanism 70 operates in the forward swing mode (reverse swing mode) of the swing mechanism 90, a rotational force with the left - right direction as the axial direction is likely to act on the front and rear connecting portions of the connecting rod 71. On the other hand, in the present embodiment, the joint portion 74 rotatably connects the connecting rod 71 and the first eccentric shaft portion 60A with the left - right direction as the axial direction, and rotatably connects the connecting rod 71 and the plunger 72 with the left - right direction as the axial direction. Therefore, even in the forward swing mode (reverse swing mode) of the swing mechanism 90, the reciprocating mechanism 70 can be operated well and the plunger 72 can be swung well.

[0077] Further, the swing mechanism 90 is configured to be switchable between a forward swing mode and a reverse swing mode. Thereby, according to the working form of the operator, by switching the mode of the swing mechanism 90, the workability during cutting can be improved.

[0078] Further, a regulating member 108 is provided on the plunger 72, and rotation about the longitudinal direction of the connecting rod 71 as the axial direction is regulated by the regulating member 108. Specifically, a pair of left and right regulating portions 108D are provided on the regulating member 108, and the regulating portions 108D are adjacently disposed below the outer ends in the left and right directions of the front end portion of the connecting rod 71 and are configured to be able to contact the connecting rod 71. Thereby, when the connecting rod 71 contacts the regulating portion 108D, rotation about the longitudinal direction of the connecting rod 71 as the axial direction is regulated. Therefore, while suppressing the power transmission loss from the connecting rod 71 to the plunger 72, the rotational movement of the first eccentric shaft portion 60A that eccentrically rotates about the axis AL can be efficiently converted into the reciprocating movement in the front and rear directions of the plunger 72.

[0079] Further, a vibration reduction mechanism 110 is provided above the reciprocating mechanism 70 and overlaps a part of the connecting rod 71 and the plunger 72 in a plan view. That is, in the normal swing mode (reverse swing mode) of the swing mechanism 90, the vibration generated by the plunger 72 that swings up and down during the reciprocating movement in the front and rear directions can be efficiently absorbed by the vibration reduction mechanism 110. Thereby, the workability with respect to the work difference can be improved.

[0080] In addition, in the present embodiment, the connecting rod 71 and the first eccentric shaft portion 60A are connected by the joint portion 74, and the connecting rod 71 and the plunger 72 are connected. However, depending on the operating conditions of the reciprocating mechanism 70, one of the front and rear joint portions 74 may be omitted. In this case, the connecting rod 1 and the first eccentric shaft portion 60A or the plunger 72 may be rotatably connected with the vertical direction as the axial direction.

[0081] Further, in the present embodiment, the regulating member 108 is fixed to the plunger 72. However, the regulating member 108 may be configured as a blade mounting mechanism 80 so as to be able to contact the connecting rod 71. Further, the regulating member 108 may be fixed to the connecting rod 71 and configured to be able to contact the plunger 72.

Description of Symbols

[0082] 10 Electric cutting machine (working machine) 40 Motor 51 Transmission gear (rotating body) 60A First eccentric shaft portion (eccentric portion) 62 Sleeve 70 Reciprocating mechanism (conversion mechanism) 71 Connecting rod 72 Plunger (reciprocating moving portion) 74 Joint portion 75 Needle bearing (rolling member) 76 Inner sleeve (first joint member) 76A Convex spherical surface portion 77 Outer sleeve (second joint member) 77A Concave spherical surface portion 80 Blade mounting mechanism (tool mounting portion) 82 Blade (tip tool) 82A Blade portion 90 Swing mechanism 91 Support guide mechanism portion (first guide portion) 95 Rear guide mechanism portion (second guide portion) 108 Regulation member 108D Regulation portion 110 Vibration reduction mechanism S Spherical sliding bearing structure

Claims

1. A motor, an eccentric part that eccentrically rotates about an axis extending in a predetermined direction by driving of the motor, a conversion mechanism that converts the rotational motion of the eccentric part into a reciprocating motion, and is provided with, the conversion mechanism includes, a connecting rod connected to the eccentric part, a reciprocating movement part connected to the connecting rod and reciprocatingly moving in a first intersecting direction intersecting the predetermined direction, a swing mechanism including a guide surface inclined with respect to the first intersecting direction for displacing one end of the reciprocating movement part in the predetermined direction during the reciprocating movement of the reciprocating movement part, a joint part, and is configured to include, the joint part rotatably connects the connecting rod to at least one of the eccentric part and the reciprocating movement part with the predetermined direction as an axial direction, and has a spherical sliding bearing structure that rotatably guides with a second intersecting direction intersecting the predetermined direction and the first intersecting direction as an axial direction. Working machine.

2. A motor, an eccentric part that eccentrically rotates about an axis extending in a predetermined direction by driving of the motor, a conversion mechanism that converts the rotational motion of the eccentric part into a reciprocating motion, and is provided with, the conversion mechanism includes, a connecting rod connected to the eccentric part, a reciprocating movement part connected to the connecting rod, extending in a first intersecting direction intersecting the predetermined direction, and reciprocatingly moving in the first intersecting direction, a swing mechanism including an inclined guide inclined with respect to the first intersecting direction for displacing one end of the reciprocating movement part in the predetermined direction during the reciprocating movement of the reciprocating movement part, a joint part, and is configured to include, the joint part rotatably connects the connecting rod to at least one of the eccentric part and the reciprocating movement part with the predetermined direction as an axial direction, and rotatably guides with a second intersecting direction intersecting the predetermined direction and the first intersecting direction as an axial direction. Working machine.

3. The working machine according to claim 2, wherein the joint part has a spherical sliding bearing structure.

4. The joint part has a first joint member and a second joint member, the spherical sliding bearing structure includes, a convex spherical surface part formed on the first joint member, a concave spherical surface part formed on the second joint member and configured to be slidable on the convex spherical surface part, The working machine according to claim 1 or claim 3, which is configured to include.

5. The joint part has a rolling member, and through the rolling member, the connecting rod is rotatably connected to at least one of the eccentric part and the reciprocating movement part with the predetermined direction as the axial direction. The working machine according to claim 1 or claim 2.

6. The connecting rod and the reciprocating movement part are connected by the joint part, The reciprocating movement part is provided with a tool mounting part to which a tip tool is mounted, The reciprocating movement of the reciprocating movement part is guided by a swing mechanism, When the reciprocating movement part reciprocates, the reciprocating movement part swings by the swing mechanism and the tool mounting part swings in the predetermined direction. The working machine according to claim 1.

7. The reciprocating movement part extends in the first crossing direction, the tool mounting part is provided at one end in the longitudinal direction of the reciprocating movement part, and the connecting rod is connected to the other end in the longitudinal direction of the reciprocating movement part, The swing mechanism is A first guide part that guides the movement of the reciprocating movement part in the first crossing direction, A second guide part that is located at a position separated from the first guide part in the first crossing direction and guides the movement of the reciprocating movement part in the first crossing direction, And has When guiding the reciprocating movement part by the first guide part and the second guide part, the other end in the longitudinal direction of the reciprocating movement part is displaced to one side or the other side in the predetermined direction by the second guide part, and the first guide part supports the reciprocating movement part so as to be swingable. The working machine according to claim 6.

8. A blade part is provided at one end in the predetermined direction of the tip tool mounted on the tool mounting part, The swing mechanism is configured to be switchable between a normal swing mode and a reverse swing mode, In the normal swing mode, when the reciprocating movement part moves forward, the tool mounting part moves to one side in the first crossing direction and the other side in the predetermined direction, and when the reciprocating movement part moves backward, the tool mounting part moves to the other side in the first crossing direction and one side in the predetermined direction, In the reverse swing mode, when the reciprocating movement part moves forward, the tool mounting part moves to one side in the first crossing direction and one side in the predetermined direction, and when the reciprocating movement part moves backward, the tool mounting part moves to the other side in the first crossing direction and the other side in the predetermined direction. The working machine according to claim 7.

9. The connecting rod extends in the first crossing direction, The working machine according to claim 6, wherein the swing mechanism has a regulating member that regulates rotation about the longitudinal direction of the connecting rod as an axial direction.

10. The working machine according to claim 9, wherein the regulating member is provided on at least one of the connecting rod, the reciprocating movement portion, and the tool mounting portion.

11. The regulating member has a regulating portion that regulates the rotation of the connecting rod by coming into contact therewith, The working machine according to claim 9, wherein, when viewed from the predetermined direction, the regulating portion is provided on both sides of the joint portion in the second crossing direction.

12. A motor having a predetermined direction as an axial direction, A rotating body that rotates about the predetermined direction as an axial direction by the driving force of the motor, An eccentric portion that is integrally rotatably provided on the rotating body and is disposed at a position eccentric with respect to the axis of the rotating body, A conversion mechanism that converts the rotational motion of the eccentric portion that eccentrically rotates about the axis of the rotating body into a reciprocating motion, Comprising: The conversion mechanism is A connecting rod connected to the eccentric portion, A reciprocating movement portion that is connected to the connecting rod and reciprocates in a first crossing direction that intersects the predetermined direction, A joint portion, And is configured to include, The joint portion is configured to rotatably connect the connecting rod to at least one of the eccentric portion and the reciprocating movement portion about the predetermined direction as an axial direction, and to rotatably guide about a second crossing direction that intersects the predetermined direction and the first crossing direction as an axial direction. Working machine.

13. The motor is disposed on one side in the predetermined direction of the rotating body and the conversion mechanism, On the other side in the predetermined direction of the conversion mechanism, a vibration reduction mechanism is provided, and when viewed from the predetermined direction, at least a part of the reciprocating movement portion overlaps the vibration reduction mechanism, The working machine according to claim 12, wherein the vibration reduction mechanism reduces vibration generated during the reciprocating movement of the reciprocating movement portion.

Images