Work equipment

Abstract

The present invention suppresses an increase in the number of components and thereby reduces costs. In a reciprocating motion mechanism part 70B of a driving mechanism 70 of an electric cutting device 10, a connector 83 of a plunger 82 is inserted in a slit 80A of a guide metal 80 so as to be movable in the frontward and backward directions. The guide metal 80 is disposed adjacently above a gear 71 of a gear mechanism part 70A. Thus, the guide metal 80 above the gear 71 receives the gear 71, which moves upward due to a thrusting force, and thereby acts as a stopping member that restricts the upward movement of the gear 71. Thus, in the gear mechanism part 70A, using the guide metal 80 of the reciprocating motion mechanism part 70B makes it possible restrict the upward movement of the gear 71. In other words, in the gear mechanism part 70A, it is possible to restrict the upward movement of the gear 71 without providing a separate member for restricting the upward movement of the gear 71.

Description

Technical Field

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

Background Art

[0002] The saber saw (working machine) described in Patent Document 1 below has a main body case housed in a gear housing, a gear part housed in the main body case, and a plunger connected to the gear part. A blade (tip tool) is attached to the front end of the plunger. Then, the driving force of the motor is transmitted to the plunger via the gear part, and the plunger reciprocates in the front-rear direction together with the blade. Thereby, cutting processing can be performed on the workpiece to be cut. That is, the gear part and the plunger for operating the tip tool are configured as a drive mechanism for operating the tip tool.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, in the drive mechanism of the above working machine, the operating drive members are received operably by support members such as bearings. Therefore, in the drive mechanism, if a support member is set for each drive member, the number of parts of the drive mechanism increases, which may lead to an increase in the cost of the drive mechanism and the working machine. For this reason, it is desirable that the working machine has a configuration that can suppress an increase in the number of parts and reduce costs.

[0005] In consideration of the above facts, an object of the present invention is to provide a working machine that can suppress an increase in the number of parts and reduce costs.

Means for Solving the Problems

[0006] One or more embodiments of the present invention include a motor having a drive shaft, a drive mechanism connected to the motor for reciprocating a cutting tool in the forward and backward direction, and a case housing the drive mechanism, wherein the drive mechanism is It is configured as a separate component from the aforementioned drive shaft, The rotational force of the drive shaft is transmitted, vertical direction A first drive member that rotates around an axis extending in the direction, and a second drive member that can hold the tip tool and reciprocates in the forward and backward direction by the power of the first drive member, The case is fixed to the aforementioned case, The aforementioned vertical direction in , part between the first drive member and the second drive member to position death , the first drive member vertical direction The work machine is configured to include a support member that restricts the movement of the second drive member and supports the second drive member so that it can be driven back and forth.

[0007] One or more embodiments of the present invention include a motor having a drive shaft, a drive mechanism connected to the motor for reciprocating a cutting tool in the forward and backward direction, and a case housing the drive mechanism, wherein the drive mechanism is It is configured as a separate component from the aforementioned drive shaft, The rotational force of the drive shaft is transmitted, vertical direction A first drive member that rotates around an axis extending in a certain direction, and a part capable of holding the tip tool, and the motor In the aforementioned front-to-back direction A second drive member that reciprocates, and the first drive member vertical direction The first drive member has a support member that restricts the movement of the first drive member and supports the second drive member so that it can be driven back and forth, and the first drive member is the support member vertical direction The support member is positioned on one side of the first drive member and is configured as a facing surface that faces the first drive member and supports the first drive member, and vertical direction The work machine is configured to include a second receiving portion which is configured as a slit open in a direction perpendicular to the second drive member and supports the second drive member.

[0008] One or more embodiments of the present invention are that the first drive member is the support member vertical directionThe support member is positioned on one side of the first drive member and is configured as a facing surface that faces the first drive member and supports the first drive member, and vertical direction A work machine having a second receiving portion which is configured as a slit open in a direction perpendicular to the direction and supports the second drive member. In addition, one or more embodiments of the present invention are that the first drive member is vertical direction The work machine is a gear configured to be rotatable in the axial direction. In addition, one or more embodiments of the present invention, the receiving member is the vertical direction This is a work machine positioned opposite the gear.

[0009] One or more embodiments of the present invention are ,before The second drive member extends in the front-rear direction, and when the drive mechanism is in operation, the second drive member reciprocates in the front-rear direction. The tip tool is connected to one end of the second drive member, and the other end of the second drive member is guided by the support member so as to be movable in the front-rear direction.

[0010] One or more embodiments of the present invention are ,before The second drive member extends in the front-rear direction, and the drive mechanism is Left and right direction This is a work machine having a pair of the aforementioned support members arranged at a distance from each other.

[0011] One or more embodiments of the present invention are provided in the first drive member, the first drive member is provided with a connecting portion, the connecting portion connects the first drive member and the second drive member to transmit the power of the motor to the second drive member, and Left and right direction It is a work machine positioned between a pair of the aforementioned support members.

[0012] One or more embodiments of the present invention are such that the drive mechanism has a third drive member that is operated by the power of the first drive member, a counterweight is housed in the case, and by the third drive member transmitting power to the counterweight, the counterweight reciprocates in the front-back direction in a reverse phase to the second drive member, and the third drive member is vertical direction disposed on the opposite side of the support member from the first drive member, and the support member is a working machine that operably receives the third drive member.

[0013] One or more embodiments of the present invention are The first drive member is provided with a connecting portion, which connects the first drive member and the second drive member to transmit power from the motor to the second drive member, and also connects the first drive member and the third drive member to transmit power from the motor to the third drive member. a working machine.

[0014] One or more embodiments of the present invention are a working machine in which the receiving member is configured as a single component.

[0015] One or more embodiments of the present invention are a working machine in which the receiving member is made of a sintered material and the receiving member is impregnated with a lubricant.

[0016] One or more embodiments of the present invention include a motor having a drive shaft, a drive mechanism connected to the motor for reciprocating a tip tool in the front-back direction, and a case housing the drive mechanism, and the drive mechanism It is configured as a separate component from the aforementioned drive shaft, by transmitting the rotational force of the drive shaft, vertical direction a first drive member that rotationally drives about an axis extending thereto, and a second drive member that can hold the tip tool and reciprocally drives in the front-back direction by receiving power from the first drive member, via the second drive member the load during work The front is transmitted to the first drive member described above , and power from the drive shaft when the first drive member In the vertical direction the second drive member from is separated, and an elastic body that is pressed against the first drive member and elastically deformed, and is a working machine configured to include. twist

[0017] ​One or more embodiments of the present invention are a work machine comprising a motor, a drive mechanism connected to the motor for operating a cutting tool, and a case housing the drive mechanism, wherein the case comprises a box-shaped case body having an opening that opens to one side in a first direction, and a cover that closes the opening, and the drive mechanism is arranged so as not to protrude beyond the opening to one side in the first direction. [Effects of the Invention]

[0018] According to one or more embodiments of the present invention, it is possible to reduce costs by suppressing an increase in the number of parts. [Brief explanation of the drawing]

[0019] [Figure 1] This is a side view from the right, showing the electric cutting machine according to this embodiment. [Figure 2] Figure 1 is a side view from the right, showing the inside of the electric cutting machine. [Figure 3] Figure 2 is a longitudinal cross-sectional view from the right side, showing the inside of the inner case. [Figure 4] This is a cross-sectional view (section 4-4 in Figure 3) showing the interior of the rear part of the inner case, as seen from the front. [Figure 5] Figure 2 is a cross-sectional view (section 5-5 in Figure 2) taken from the rear, showing the fastening and fixing state between the case cover and the case body at the rear end of the inner case. [Figure 6] Figure 2 is a perspective view taken from the left front, showing the inner case with the case cover removed from the case body. [Figure 7] Figure 6 is a perspective view of the inner case body, taken from the left front. [Figure 8] Figure 6 is a plan view showing the drive mechanism housed in the case body, with the vibration reduction mechanism removed. [Figure 9] Figure 3 is an exploded perspective view taken from the left front, showing the reciprocating mechanism of the drive mechanism. [Figure 10] Figure 3 is an exploded perspective view taken from the left front, showing the vibration reduction mechanism of the drive mechanism. [Modes for carrying out the invention]

[0020] The electric cutting machine 10 as a work machine according to this embodiment will be described below with reference to the drawings. The arrows UP, FR, and RH shown in the drawings as appropriate indicate the upper, front, and right sides of the electric cutting machine 10, respectively. In the following description, when the directions of up and down, front and back, and left and right are used, they refer to the up and down direction, front and back direction, and left and right direction of the electric cutting machine 10, unless otherwise specified. The up and down direction corresponds to the first direction of the present invention, the front and back direction corresponds to the second direction of the present invention, and the left and right direction corresponds to the third direction of the present invention.

[0021] The electric cutting machine 10 is configured as an electric tool for cutting materials such as pipes. As shown in Figures 1 and 2, the electric cutting machine 10 is configured including a housing 20 that forms the outer casing of the electric cutting machine 10, an inner case 40 which is a case housed and fixed inside the housing 20, a motor 60 which is a drive source assembled to the inner case 40, and a drive mechanism 70 which is housed inside the inner case 40. The following describes each component of the electric cutting machine 10.

[0022] (About the housing 20) The housing 20 is formed in a substantially hollow cylindrical shape that extends in the front-to-back direction as a whole. The housing 20 is composed of two housing members that are divided in the left-to-right direction, and these left and right housing members are assembled together to form the housing 20. The housing 20 is composed of a front housing portion 20A that constitutes the front part of the housing 20 and a handle housing portion 20B that constitutes the rear end of the housing 20 as a handle. The front housing portion 20A extends in the front-to-back direction, and the rear end of the front housing portion 20A is bent downward. The handle housing portion 20B extends in the up-to-down direction, and both of the up and down ends of the handle housing portion 20B are bent forward and connected to the rear end of the front housing portion 20A. During cutting, the operator grips the handle housing portion 20B and performs the cutting process.

[0023] A trigger 22 is provided on the upper end portion of the handle housing 20B. The trigger 22 protrudes forward from the handle housing 20B and is configured to be pullable backward. A switch mechanism 24 is provided on the handle housing 20B behind the trigger 22. The switch mechanism 24 has a switch (not shown) that is operated by the trigger 22, and this switch is electrically connected to a control unit 26. The control unit 26 is provided at the lower end of the rear end of the front housing 20A. An output signal corresponding to the operation of the trigger 22 is output from the switch to the control unit 26.

[0024] Furthermore, a battery 28 is detachably mounted from the rear to the lower end of the handle housing 20B. The battery 28 is electrically connected to the control unit 26 and the motor 60 (described later), and power is supplied from the battery 28 to the control unit 26 and the motor 60.

[0025] (Regarding the inner case 40) As shown in Figures 2 to 8, the inner case 40 is formed as a roughly rectangular box shape that extends in the front-to-back direction. The inner case 40 is housed in the upper part of the front housing portion 20A and is fixed to the housing 20 by being sandwiched from the outside in the left-right direction by the housing members that make up the housing 20. The inner case 40 consists of a case body 42 and a case cover 44 as a cover, and the case cover 44 is fastened and fixed to the case body 42.

[0026] (Regarding the case body 42) The case body 42 is made of metal and is formed by casting. The case body 42 as a whole is formed in a roughly rectangular box shape that extends in the front-to-back direction and is open to the top. At the bottom of the rear of the case body 42, a gear housing section 42A (see Figure 4) for housing the gear 71, which will be described later, is formed. The gear housing section 42A is formed in a two-stage stepped cylindrical shape with the vertical direction as the axial direction. Specifically, the gear housing section 42A is composed of an upper housing section 42A1 which constitutes the upper part of the gear housing section 42A, an intermediate housing section 42A2 which constitutes the vertical middle part of the gear housing section 42A, and a lower housing section 42A3 which constitutes the lower part of the gear housing section 42A. The diameter of the intermediate housing section 42A2 is set to be larger than the diameter of the lower housing section 42A3, and the diameter of the upper housing section 42A1 is set to be larger than the diameter of the intermediate housing section 42A2. The upper housing section 42A1 protrudes upward from the bottom wall of the case body 42. Furthermore, the left and right sides of the upper housing section 42A1 extend outward from the side walls of the case body 42, forming the outer casing of the case body 42. A ball groove 42B (see Figures 3 and 4) is formed on the outer circumference of the lower surface of the intermediate housing section 42A2, extending circumferentially. The ball groove 42B is formed around the entire circumference of the intermediate housing section 42A2. Multiple rolling balls 50 are provided inside the ball groove 42B, arranged in a line along the circumferential direction of the ball groove 42B. The upper ends of the rolling balls 50 are positioned above the bottom surface of the upper housing section 42A1 and are located within the upper housing section 42A1. Below the rolling balls 50, a thrust washer 50A and a cushioning rubber 50B are provided. The cushioning rubber 50B corresponds to the elastic body of the present invention.

[0027] At the bottom of the case body 42, behind the gear housing 42A, a shaft housing 42C (see Figure 3) is formed as a communication section for housing a portion of the drive shaft 61 of the motor 60, which will be described later. The shaft housing 42C is formed in a substantially stepped cylindrical shape with the vertical direction as the axial direction, and the diameter of the upper part of the shaft housing 42C is set to be smaller than the diameter of the lower part of the shaft housing 42C. The inside of the shaft housing 42C is through in the vertical direction, and the inside and outside of the case body 42 are in communication through the shaft housing 42C. Also, in a plan view, the shaft housing 42C is positioned to overlap with the rear end of the gear housing 42A, and the inside of the shaft housing 42C is in communication with the inside of the upper housing 42A1.

[0028] As shown in Figures 7 and 8, a pair of left and right protruding portions 42D are formed on the upper rear of the case body 42, extending outward in the left-right direction. The protruding portions 42D project in the front-rear direction relative to the gear housing 42A, and the upper end of the upper housing portion 42A1 of the gear housing 42A is connected to the bottom wall 42D1 of the protruding portion 42D. The bottom walls 42D1 of the left and right protruding portions 42D are connected to each other at the rear of the gear housing 42A. In addition, positioning pieces 42A4 are formed at the front and rear ends of the upper housing portion 42A1 of the gear housing 42A, and the positioning pieces 42A4 project upward above the upper housing portion 42A1 and the bottom wall 42D1 of the protruding portion 42D. Rear fixing bosses 42E are formed at the front-rear outer ends of the bottom wall 42D1 of the protruding portion 42D. The rear fixing boss 42E is formed in a substantially cylindrical shape with its vertical direction as the axial direction, and protrudes upward from the bottom wall 42D1 (see Figure 5). The upper end surface of the rear fixing boss 42E is positioned below the upper end surface of the case body 42. Female threads are formed on the inner circumference of the rear fixing boss 42E. A pair of left and right fixing ribs 42E1 are formed on the rear fixing boss 42E, and the fixing ribs 42E1 extend inward in the front-rear direction from the outer circumference on both the left and right sides of the rear fixing boss 42E.

[0029] The bottom wall 42D1 of each of the pair of protruding portions 42D has a pair of front and rear mounting portions 42F formed thereon for installing the guide metal 80, which will be described later. The mounting portions 42F are formed in a substantially disc shape with the vertical direction as the thickness direction, protruding upward from the bottom wall 42D1 and positioned inward in the front-rear direction of the protruding portion 42D relative to the rear fixing boss 42E. In addition, multiple (five in this embodiment) positioning ribs 42G are integrally formed on each of the pair of protruding portions 42D between the front and rear pair of rear fixing bosses 42E. The positioning ribs 42G are formed in a substantially rectangular column shape, extending upward from the bottom wall 42D1 of the protruding portion 42D and connected to the left and right side walls of the protruding portion 42D. The multiple positioning ribs 42G are arranged in a line at equal intervals in the front-rear direction.

[0030] Furthermore, a pair of front fixing bosses 42H are formed on the front end of the case body 42. The front fixing bosses 42H are formed in a substantially cylindrical shape with the vertical direction as the axial direction and extend upward from the bottom wall of the case body 42. The front fixing bosses 42H are connected to the left and right side walls of the case body 42, and the upper end surface of the front fixing bosses 42H is flush with the upper end surface of the case body 42. Female threads are formed on the inner circumference of the front fixing bosses 42H.

[0031] An insertion portion 42J is formed in the front wall of the case body 42 for inserting a plunger 82, which will be described later. The insertion portion 42J is formed as a groove that is open upwards and penetrates in the front-rear direction. A motor holder portion 42K is formed at the rear end of the case body 42 as a holder portion for holding the motor 60, which will be described later. The motor holder portion 42K is formed as a roughly rectangular cylindrical shape that protrudes downwards from the case body 42 and is arranged coaxially with the shaft housing portion 42C, and each side wall of the motor holder portion 42K has a notch portion 42K1 that is open downwards. In other words, the motor holder portion 42K can be said to be composed of four column portions 42K2.

[0032] A mounting piece 42L is integrally formed at the lower end of the front wall of the case body 42. The mounting piece 42L is formed in a substantially rectangular plate shape with the vertical direction being the thickness direction and extends forward from the front wall of the case body 42. As shown in Figures 3 and 6, a fixing plate 52 is provided on the lower side of the mounting piece 42L. The fixing plate 52 is formed in a substantially U-shaped plate shape that is open to the top when viewed from the front and is fastened and fixed to the mounting piece 42L via a stay 54. As shown in Figure 6, a base 56 is provided at the front end of the fixing plate 52. When viewed from the front, the fixing plate 52 is formed in a substantially rectangular frame shape with the vertical direction being the longitudinal direction, and the lower end portion of the base 56 is rotatably connected to the front end of the fixing plate 52 with the left-right direction being the axial direction.

[0033] (Regarding the case cover 44) As shown in Figure 6, the case cover 44 is made of a metal plate and is formed by press working (punching). The case cover 44 is formed in a substantially rectangular flat plate shape with the plate thickness direction in the vertical direction and extending in the front-rear direction. The outer shape of the case cover 44 is formed to match the outer shape of the upper end of the case body 42 in a plan view. Fixing holes 44A are formed through the outer circumference of the case cover 44 at positions corresponding to the rear fixing boss 42E and the front fixing boss 42H of the case body 42. Fixing bolt BL1, as a fastening member, is inserted from above into the fixing hole 44A corresponding to the rear fixing boss 42E and screwed into the inner circumference of the rear fixing boss 42E, and fixing bolt BL2, as a fastening member, is inserted from above into the fixing hole 44A corresponding to the front fixing boss 42H and screwed into the inner circumference of the front fixing boss 42H. As a result, the case cover 44 is fixed to the case body 42, and the upper opening 42M of the case body 42 is closed by the case cover 44.

[0034] A gasket 46 is provided between the outer periphery (bottom surface) of the case cover 44 and the case body 42 (top surface). The gasket 46 is made of an elastic material such as rubber and is formed in a frame shape with the thickness in the vertical direction, and the thickness of the gasket 46 is set to be relatively thin. As a result, the opening 42M of the case body 42 is sealed and closed by the gasket 46 and the case cover 44.

[0035] As also shown in Figure 5, a fixing sleeve 48 is provided as a fastening device between the case cover 44 (packing 46) and the rear fixing boss 42E. The fixing sleeve 48 is formed in a substantially cylindrical shape with the vertical direction as its axial direction, and the fixing bolt BL1 is inserted through the fixing sleeve 48. In other words, the case cover 44 is fastened and fixed to the rear fixing boss 42E via the fixing sleeve 48. A stepped portion 48A is formed on the outer circumference of the fixing sleeve 48 in the middle of the vertical direction, and the diameter of the upper part of the fixing sleeve 48 is set to be larger than the diameter of the lower part of the fixing sleeve 48.

[0036] (Regarding the motor 60) As shown in Figures 2 and 3, the motor 60 is configured as a brushless motor and is located below the rear end of the case body 42. The motor 60 has a drive shaft 61 as a transmission member. The drive shaft 61 extends in the vertical direction, and a gear section 61A, which is composed of a bevel gear, is formed at the upper end of the drive shaft 61. The upper end portion of the drive shaft 61 is housed in the shaft housing section 42C of the case body 42, and the upper end portion of the drive shaft 61 protrudes upward from the shaft housing section 42C and is located within the rear end of the gear housing section 42A. The upper end portion of the drive shaft 61 is rotatably supported by a motor bearing 65 fixed to the lower part of the shaft housing section 42C. The lower end portion of the drive shaft 61 is rotatably supported by a motor bearing 66, which is fixed to a bearing holder 67 assembled to the case body 42.

[0037] The bearing holder 67 has a holder base 67A and four arm portions 67B. The holder base 67A is formed in a substantially rectangular plate shape with the vertical direction being the thickness direction, and a bearing holding portion 67C is formed in the approximate center of the holder base 67A, which protrudes downward and is open to the upward. The motor bearing 66 is fitted into the bearing holding portion 67C and fixed to the bearing holder 67. The arm portions 67B extend upward from the four corners of the holder base 67A. The upper ends of the arm portions 67B are positioned inside the motor holding portion 42K of the case body 42 and are assembled to the motor holding portion 42K.

[0038] The rotor 62 and stator 63 of the motor 60 are positioned radially outward at the lower part of the drive shaft 61 and inside the motor holder 42K. A fan 68 is also provided on the upper end of the drive shaft 61 so as to rotate integrally with it, and the fan 68 is positioned close to the lower side of the motor bearing 65. The fan 68 is configured as a centrifugal fan.

[0039] (Regarding the drive mechanism 70) As shown in Figures 3 and 6, the drive mechanism 70 is housed inside the inner case 40. The drive mechanism 70 is composed of a gear mechanism 70A as the first drive mechanism, a reciprocating mechanism 70B as the second drive mechanism, and a vibration reduction mechanism 70C as the third drive mechanism.

[0040] (Regarding the gear mechanism 70A) As shown in Figures 3 and 4, the gear mechanism 70A is mainly composed of a gear 71 (transmission gear) as the first drive member, and the gear 71 is formed in a substantially disc shape with the vertical direction as the thickness direction. The gear 71 is housed in the upper housing portion 42A1 of the gear housing portion 42A and is placed on top of a plurality of rolling balls 50. A gear hole 71A is formed through the center of the gear 71. The upper end of a gear shaft 72 (support shaft) with the vertical direction as the axial direction is inserted into the gear hole 71A, and the gear hole 71A is rotatably supported by the gear shaft 72 via a needle bearing 73. The lower part of the gear shaft 72 is supported by a cylindrical bush 74, which is provided inside the intermediate housing portion 42A2 and the lower housing portion 42A3 of the gear housing portion 42A. As described above, the gear 71 is housed in the gear housing 42A so as to be rotatable in the vertical direction as the axial direction, while being supported from below by the rolling balls 50. The rolling balls 50 move circumferentially by rolling around the gear shaft 72 in response to the rotational force of the gear 71. Since the rolling balls 50 are configured to roll on the surface of the gear 71, friction between the rolling balls 50 and the gear 71 is reduced. In addition, although the rolling balls 50 are supported by the thrust washer 50A, they roll on the surface of the thrust washer 50A during rolling movement. Therefore, friction between the rolling balls 50 and the thrust washer 50A is reduced.

[0041] A gear portion 71B, composed of a helical gear, is formed on the outer circumference of the gear 71, and the gear portion 71B meshes with the gear portion 61A of the drive shaft 61 of the motor 60. As a result, when the motor 60 is in operation (especially when the load on the motor 60 is large), the gear 71 rotates, and a thrust force in the vertical direction (mainly downward) is generated on the gear 71 due to the meshing action of the gear portion 61A and gear portion 71B, which are composed of helical gears. Conversely, the gear portion 61A and gear portion 71B, which are composed of helical gears biteIn this configuration, a downward thrust force is generated on the gear 71 when the load on the motor 60 increases. Specifically, an example of when a thrust force is generated is when the blade 95, described later, moves to the rear by the drive mechanism 70 to cut the material to be cut. A downward thrust force acts on the gear 71, and the rolling ball 50 receives this thrust force. Specifically, when a downward thrust force acts on the gear 71, the gear 71 moves relative to the gear shaft 72 (sliding downward or tilting in the vertical direction), and the rolling ball 50 is configured to receive this movement. When a downward thrust force acts on the rolling ball 50, this thrust force is transmitted to the cushioning rubber 50B (elastic body) via the thrust washer 50A. As a result, the thrust force is absorbed by the cushioning rubber 50B, and damage or deformation of the transmission mechanism for transmitting power from the motor 60 to the blade 95 due to the thrust force is suppressed.

[0042] A crankpin 75 is provided on the gear 71 so as to be rotatable as a connecting part. The crankpin 75 is formed in a substantially cylindrical shape with its axial direction in the vertical direction, is positioned eccentrically with respect to the rotation axis of the gear 71, and protrudes upward from the gear 71. A cylindrical sleeve 77 is rotatably provided on the crankpin 75 via a needle bearing 76, and the upper end of the crankpin 75 protrudes above the needle bearing 76 and the sleeve 77.

[0043] (Regarding the reciprocating mechanism 70B) As shown in Figures 3 to 6, 8, and 9, the reciprocating mechanism 70B is housed in the case body 42 above the gear mechanism 70A. The reciprocating mechanism 70B is composed of a pair of left and right support members (receiving members) of guide metal 80 and a second drive member, a plunger 82 (output section).

[0044] (Regarding the guide metal 80) The left and right pair of guide metals 80 are made of sintered material and are impregnated with lubricant. The guide metal 80 is formed in a substantially rectangular plate shape with the front-to-back direction as the longitudinal direction and the up-to-down direction as the thickness direction, and is also formed in a substantially U-shape that is open inward in the left-to-right direction when viewed from the front-to-back direction. That is, a slit 80A is formed in the upper-to-lower middle part of the guide metal 80 as a second receiving part (second support part), and the slit 80A is formed in a groove shape that is open inward in the left-to-right direction and penetrates in the front-to-back direction. In addition, the lower surface 80B and upper surface 80C of the guide metal 80 are arranged along a plane perpendicular to the up-to-down direction, serving as the first receiving part (first support part).

[0045] As shown in Figures 4 and 8, the guide metal 80 is housed in the protruding portion 42D of the case body 42, and the lower surface 80B of the guide metal 80 is installed on the mounting portion 42F of the protruding portion 42D. The guide metal 80 is positioned between a pair of front and rear fixing bosses 42E, and the front-rear position of the guide metal 80 is determined by the fixing ribs 42E1 on the rear fixing bosses 42E. The guide metal 80 is also positioned between the positioning piece 42A4 and the positioning rib 42G of the case body 42, and the left-right position of the guide metal 80 is determined by the positioning piece 42A4 and the positioning rib 42G.

[0046] A relief recess 80D (see Figure 8) is formed in the left-right inner portion of the guide metal 80 in the front-rear intermediate portion. In plan view, the relief recess 80D is formed in a substantially arc-shaped concave form centered on the rotation axis of the gear 71, opening inward in the left-right direction and penetrating in the vertical direction. Furthermore, the edge of the relief recess 80D on the guide metal 80 is positioned close to the upper side of the outer circumference on both the left-right sides of the gear 71, and a predetermined gap is formed in the vertical direction between the guide metal 80 and the gear 71. As a result, when a thrust force acts upward on the gear 71 during rotation and the gear 71 moves upward, the lower surface 80B of the guide metal 80 receives the thrust force and restricts the upward movement of the gear 71. At this time, the outer circumference of the gear 71 slides on the lower surface 80B of the guide metal 80. In other words, the guide metal 80 is configured as a stopper member that receives the gear 71 moving upward (to one side in the thrust direction) and restricts the upward movement of the gear 71. Furthermore, the lower surface 80B of the guide metal 80 is configured as a receiving surface for the gear 71, and also as a positioning surface that determines the vertical position of the guide metal 80 (the rear end of the reciprocating mechanism 70B).

[0047] (Regarding the plunger 82) As shown in Figures 3, 4, 8, and 9, the plunger 82 is formed in an elongated shape extending in the front-rear direction. The plunger 82 is composed of a connector 83 that constitutes the rear part of the plunger 82 and an output shaft 84 that constitutes the front part of the plunger 82. The connector 83 is formed in a substantially T-shaped plate with the vertical direction being the plate thickness direction. Specifically, the connector 83 is composed of a rear connector portion 83A that extends in the left-right direction and a front connector portion 83B that extends forward from the left-right middle part of the rear connector portion 83A. The left and right ends of the rear connector portion 83A are inserted into the slit 80A of the guide metal 80 so as to be movable in the front-rear direction, and the connector 83 is supported so as to be movable in the front-rear direction by a pair of left and right guide metals 80. The rear connector portion 83A is also positioned close to the left-right inner side of the bottom surface (left-right outer surface) of the slit 80A. In other words, the guide metal 80 is configured as a guide member that receives the operating connector 83 from both the upper and lower sides and guides the movement of the connector 83 in the front-rear direction. The guide metal 80 is also configured as a support member that slides and supports the connector 83 as it moves in the front-rear direction. In other words, the guide metal 80 is a sliding bearing.

[0048] The rear connector section 83A has a connecting hole 83C formed through it, and the connecting hole 83C is formed as an elongated hole with the left-right direction as its longitudinal direction. The crank pin 75, needle bearing 76, and sleeve 77 of the gear 71 are inserted into the connecting hole 83C so as to be movable in the left-right direction and engageable in the front-rear direction. As a result, the rotational force of the gear 71 is converted by the crank pin 75 including the sleeve 77, and the connector 83 (plunger 82) moves back and forth in the front-rear direction. The crank pin 75 (sleeve 77) is positioned between a pair of left and right guide metals 80, and when the gear 71 rotates, the relief recess 80D of the guide metal 80 suppresses interference between the sleeve 77 and the guide metal 80. In addition, the front connector section 83B has a material relief hole 83D formed through it, except for the front end, and the material relief hole 83D is formed as a roughly rectangular shape extending in the front-rear direction.

[0049] The output shaft 84 is formed in a substantially bottomed cylindrical shape that is open to the front. The rear end of the output shaft 84 engages with the front end of the connector 83 in the front-rear direction and is connected to the front end of the connector 83 by a plunger sleeve 85 so as not to move relative to it. The front end portion of the output shaft 84 is supported by rolling by a pair of upper and lower rollers 90 in a roller unit 87 provided at the front end of the case body 42.

[0050] The roller unit 87 comprises a roller holder 88, a pair of upper and lower roller shafts 89, and a pair of upper and lower rollers 90. The roller holder 88 is formed in a substantially U-shaped plate form that is open to the rear in a plan view, and is positioned between the left and right front fixing bosses 42H of the case body 42 and assembled to the case body 42. The roller shafts 89 are positioned with the left-right direction as the axial direction and span the left and right side walls of the roller holder 88. The roller shafts 89 are provided at the upper and lower parts of the roller holder 88, respectively. The rollers 90 are formed in a substantially disc shape with the left-right direction as the thickness direction, and the central part of the rollers 90 is rotatably supported by the roller shafts 89. The output shaft 84 is positioned between the pair of upper and lower rollers 90 and is supported by rolling motion by the rollers 90. Furthermore, the front end of the roller 90 passes through the holder hole 88A formed in the front wall of the roller holder 88 and the insertion portion 42J of the case body 42, and protrudes forward from the front wall of the case body 42.

[0051] A blade mounting mechanism 92 is provided at the front end of the output shaft 84. The blade mounting mechanism 92 has a mounting core 93. The mounting core 93 is formed in a substantially stepped cylindrical shape with the front-rear direction as its axial direction, and the mounting core 93 is fixed to the output shaft 84 with its rear end inserted into the front end of the output shaft 84.

[0052] As shown in Figures 3 and 6, a dust sleeve 30 is provided at the front end of the output shaft 84. The dust sleeve 30 is formed in a substantially bottomed cylindrical shape that is open to the front. The front end of the output shaft 84 is inserted through the bottom of the dust sleeve 30, and the blade mounting mechanism 92 is located inside the dust sleeve 30 of the housing 20. The front end of the dust sleeve 30 is assembled to the housing 20, and the dust sleeve 30 is located inside the front end of the housing 20.

[0053] The blade mounting mechanism 92 is fitted with a blade 95 (see Figure 3) as a cutting tool. The blade 95 is formed in a substantially elongated plate shape with the left-right direction being the thickness direction and extending in the front-rear direction, and the rear end of the blade 95 is fitted to the blade mounting mechanism 92. When the blade 95 is fitted, the blade 95 extends forward from the dust sleeve 30 and is positioned on the front side of the housing 20 and also positioned within the base 56. A cutting edge 95A is formed at the lower end of the blade 95, and the cutting edge 95A is formed along the entire longitudinal direction of the blade 95. As a result, when the drive mechanism 70 is operated, the blade 95 moves back and forth together with the output shaft 84.

[0054] Furthermore, the reciprocating mechanism 70B is positioned above the central part 20B1 in the vertical direction of the handle housing 20B in the aforementioned housing 20. Specifically, the central part 20B1 in the vertical direction of the handle housing 20B is positioned below the axis CL of the output shaft 84 of the reciprocating mechanism 70B (see Figure 2).

[0055] (Regarding the vibration reduction mechanism 70C) As shown in Figures 3, 4, 6, and 10, the vibration reduction mechanism 70C is housed in the rear of the case body 42 above the reciprocating mechanism 70B. The vibration reduction mechanism 70C is composed of a pair of left and right base members 100, a pair of left and right guide members 102, a ring member 104 as a third drive member, and a counterweight 108.

[0056] The base member 100 is positioned at the lower end of the vibration reduction mechanism 70C and functions as the base for the vibration reduction mechanism 70C. The base member 100 is formed in a substantially rectangular plate shape with the vertical direction being the thickness direction and the front-rear direction being the longitudinal direction. The base member 100 is positioned above the guide metal 80 (see Figures 3, 4, and 10), and the front and rear ends of the base member 100 are positioned adjacent to the upper side of the rear fixing boss 42E (see Figures 3 and 5). Positioning recesses 100A (see Figures 5 and 10) are formed through both ends of the base member 100 in the front-rear direction in the vertical direction. The positioning recesses 100A are formed in a concave shape that opens outward in the front-rear direction and are formed in an arc shape centered on the axis of the fixing sleeve 48 in a plan view. Specifically, the radius of the positioning recess 100A is substantially the same as the radius of the lower part of the fixing sleeve 48. Furthermore, a portion of the lower part of the fixing sleeve 48 is fitted into the positioning recess 100A, and the position of the base member 100 is determined by the fixing sleeve 48. In addition, the stepped portion 48A of the fixing sleeve 48 is positioned adjacent to the upper side of the edge of the positioning recess 100A. In this way, the base member 100 is fixed to the case body 42 by the fixing sleeve 48.

[0057] Furthermore, as described above, the base member 100 is positioned adjacent to the upper side of the guide metal 80. Therefore, the guide metal 80 is sandwiched vertically between the base member 100 and the mounting portion 42F of the case body 42, and is fixed to the case body 42. In other words, the base member 100 constitutes the base of the vibration reduction mechanism 70C and also functions as a stopper component that restricts the upward movement of the guide metal 80 (reciprocating mechanism 70B) and the gear 71 (gear mechanism 70A).

[0058] A base housing portion 100B is formed on the upper surface of the base member 100, excluding the front and rear ends. The base housing portion 100B is formed as a recessed area that is one step lower than the front and rear ends of the base member 100 and penetrates in the left-right direction. A guide recess 100C (see Figure 10) is formed on the left-right inner portion of the intermediate part of the base member 100 in the front-rear direction. The guide recess 100C is formed as an arc-shaped recess centered on the axis of the gear 71 in a plan view and is open to the left-right inward. Specifically, the radius of the guide recess 100C is set to be larger than the radius of the relief recess 80D of the guide metal 80, and in a plan view, the guide recess 100C is positioned radially outward of the relief recess 80D.

[0059] The pair of left and right guide members 102 extend in the front-rear direction and are formed in a substantially L-shaped plate form when viewed from the front-rear direction. Specifically, the guide member 102 is composed of a lower wall 102A that constitutes the lower end of the guide member 102 and a side wall 102B that extends upward from the left-right outer end of the lower wall 102A. The lower wall 102A of the guide member 102 is fitted into the base housing portion 100B of the base member 100, and the guide member 102 is placed on the base member 100. The front-rear movement of the base member 100 is restricted by the front end surface and rear end surface of the base housing portion 100B of the base member 100. On the side wall 102B of the guide member 102, a ball groove portion 102C is formed on the left-right inner surface and extends along the front-rear direction. The ball groove portion 102C is formed in a substantially semicircular shape that opens inward in the left-right direction when viewed from the front-rear direction and penetrates in the front-rear direction.

[0060] The ring member 104 is formed in a substantially annular shape with the vertical direction being the thickness direction. The ring member 104 is positioned between a pair of base members 100. Specifically, both left and right sides of the ring member 104 are positioned within the guide recess 100C of the base member 100, and the outer circumference of the ring member 104 is positioned adjacent to the radially inward side of the guide recess 100C. As a result, the ring member 104 is positioned coaxially with the gear 71 above the gear 71. Furthermore, both left and right sides of the ring member 104 are positioned between the guide metal 80 and the guide member 102, and the vertical movement of the ring member 104 is restricted by the guide metal 80 and the guide member 102 (see Figure 4). More specifically, both left and right sides of the ring member 104 are placed on top of the guide metal 80. That is, the guide metal 80 is configured as a stopper that supports the ring member 104 from below with its upper surface 80C, thereby restricting the downward movement of the ring member 104.

[0061] A pair of ring connecting portions 104A are integrally formed on the inner circumference of the ring member 104. The pair of ring connecting portions 104A protrude radially inward from the ring member 104 and are spaced 180 degrees apart in the circumferential direction of the ring member 104. A connector hole 104B is formed through one of the ring connecting portions 104A in the vertical direction, and the upper end of the crank pin 75 of the gear 71 is inserted into the connector hole 104B so as to be rotatable relative to it (see Figure 3). This connects the ring member 104 and the gear 71 so as to be able to rotate together. When the ring member 104 rotates, the outer circumference of the ring member 104 is guided by the guide recess 100C of the guide member 102 and is configured to slide on the upper surface 80C of the guide metal 80. In other words, the guide metal 80 is also configured as a support member that slides and supports the ring member 104. A crank pin 106 is provided on the other ring connecting portion 104A of the ring member 104, with its vertical direction being axial, and the crank pin 106 protrudes upward from the ring member 104.

[0062] The counterweight 108 is formed in a substantially rectangular plate shape with the vertical direction being the thickness direction and the front-to-back direction being the longitudinal direction. A pair of weight flanges 108A are formed in the middle of the counterweight 108 in the front-to-back direction, projecting outward in the left-to-right direction. The counterweight 108 is positioned above the ring member 104 with the weight flanges 108A positioned above the lower wall 102A of the guide member 102.

[0063] A first ball groove 108B extending in the front-rear direction is formed on the side surface of the weight flange 108A. The first ball groove 108B is formed in a substantially semicircular shape that opens outward in the left-right direction when viewed in cross-section from the front-rear direction. The first ball groove 108B is positioned opposite the ball groove 102C of the guide member 102 in the left-right direction (see Figure 4). Multiple (three in this embodiment) first rolling balls 110 are arranged within the first ball groove 108B and the ball groove 102C, and the counterweight 108 is supported by rolling motion of the first rolling balls 110. This allows the counterweight 108 to slide in the front-rear direction.

[0064] Furthermore, a plurality of biasing sleeves 112 (three in this embodiment) are provided between the guide member 102 and the side wall of the protruding portion 42D of the case body 42 (see Figures 4 and 6). The biasing sleeves 112 are made of an elastic material such as rubber and are formed in a substantially cylindrical shape with the vertical direction as the axial direction. The biasing sleeves 112 are positioned between the guide member 102 and the protruding portion 42D in a state of being compressed in the left-right direction, biasing the guide member 102 inward in the left-right direction. As a result, the first rolling ball 110 is in contact with the inner circumferential surfaces of the first ball groove portion 108B and the ball groove portion 102C, respectively.

[0065] A weight connecting hole 108C is formed through the middle of the counterweight 108 in the front-rear direction. The weight connecting hole 108C is formed as an elongated hole with the left-right direction as its longitudinal direction. The upper end of the crank pin 106 of the ring member 104 is inserted into the weight connecting hole 108C so as to be able to move relative to it in the left-right direction and engage with it in the front-rear direction. As a result, when the ring member 104 rotates, the counterweight 108 moves back and forth in the front-rear direction. Specifically, as the gear 71 and the ring member 104 rotate, the counterweight 108 moves back and forth in the front-rear direction in opposite phase to the plunger 82.

[0066] Furthermore, a pair of front-to-back second ball grooves 108D are formed on the upper surface of the counterweight 108 in the center in the left-to-right direction, and the second ball grooves 108D are positioned on the front-to-back outer side of the weight connecting hole 108C. The second ball grooves 108D extend in the front-to-back direction and are formed in a substantially semicircular shape that opens upward when viewed in cross-section from the front-to-back direction. Multiple (three in this embodiment) second rolling balls 114 are arranged within the second ball grooves 108D, and the second rolling balls 114 are in contact with the lower surface of the case cover 44 and the inner circumferential surface of the second ball grooves 108D. As a result, the counterweight 108 is supported by rolling motion by the second rolling balls 114.

[0067] In this embodiment, the upper end of the second rolling ball 114 is positioned at the same location as the upper end of the case body 42, including the packing 46, and is in contact with the lower surface of the case cover 44. In other words, the second rolling ball 114 is set so as not to protrude beyond the upper end of the case body 42, including the packing 46. Here, each component constituting the drive mechanism 70 has dimensional tolerances. Therefore, in order to ensure that the second rolling ball 114 is in contact with the lower surface of the case cover 44, the upper end of the second rolling ball 114 may be made to protrude slightly beyond the upper end of the case body 42, including the packing 46, taking into account the dimensional tolerances of the components. In other words, in the present invention, when the drive mechanism 70 is housed so as not to protrude above the opening 42M of the case body 42, it includes the case in which the upper end of the second rolling ball 114 protrudes slightly beyond the upper end of the case body 42, including the packing 46. Furthermore, in the present invention, the statement that the drive mechanism 70 is housed so as not to protrude above the opening 42M of the case body 42 indicates that the drive mechanism 70 is located below the position of the upper end (upper end) of the case body 42, which has an opening 42M that opens in a predetermined direction (upward). In this case, the predetermined direction can also be said to be the assembly direction of the case body 42 and the case cover 44. Note that the assembly direction of the case body 42 and the case cover 44 is not limited to the up and down direction. That is, the upper surface of the case body 42 may be inclined in the front-to-back direction or the left-to-right direction, and the case cover 44 may be assembled to match that upper surface.

[0068] (Operation and Effects) Next, the operation and effects of the electric cutting machine 10 of this embodiment will be described.

[0069] In the cutting operation of the electric cutting machine 10 configured as described above, the motor 60 is activated by the control unit 26 when the operator pulls the trigger 22. This causes the gear 71, which is meshed with the gear section 61A of the drive shaft 61 of the motor 60, to rotate. As a result, the plunger 82 of the reciprocating mechanism 70B, which is connected to the crankpin 75 of the gear 71, moves back and forth together with the blade 95. Thus, the material to be cut is cut.

[0070] Furthermore, when the gear 71 rotates, the ring member 104 connected to the crankpin 75 of the gear 71 rotates together with the gear 71. As a result, the counterweight 108 connected to the crankpin 106 of the ring member 104 reciprocates in the front-rear direction. The crankpins 75 and 106 are positioned 180 degrees apart in the circumferential direction of the ring member 104. Therefore, the reciprocating movement of the counterweight 108 in the front-rear direction is in opposite phase to the reciprocating movement of the plunger 82 and the blade 95 in the front-rear direction. As a result, the vibration reduction mechanism 70C acts as a dynamic vibration absorber, and the vibrations generated by the reciprocating movement of the plunger 82 and the blade 95 are reduced by the vibration reduction mechanism 70C.

[0071] In the reciprocating mechanism section 70B of the drive mechanism 70 in the electric cutting machine 10, the connector 83 of the plunger 82 is inserted into the slit 80A of the guide metal 80 so as to be movable in the front-rear direction. As a result, the guide metal 80 is configured as a guide member that supports the connector 83 from both the upper and lower sides and guides the front-rear movement of the connector 83. The guide metal 80 is also positioned adjacent to the upper side of the gear 71 that constitutes the gear mechanism section 70A. As a result, the guide metal 80 supports the gear 71 moving upward (for example, by thrust force) from above and acts as a stopper member that restricts the upward movement of the gear 71. Therefore, in the gear mechanism section 70A, the upward movement of the gear 71 can be restricted by utilizing the guide metal 80 of the reciprocating mechanism section 70B. In other words, in the gear mechanism section 70A, the upward movement of the gear 71 can be restricted without providing a separate member to restrict the upward movement of the gear 71 (to one side in the thrust direction). Therefore, the cost of the electric cutting machine 10 can be reduced by suppressing an increase in the number of parts in the drive mechanism 70 (gear mechanism section 70A). Alternatively, the guide metal 80 may be extended upwards to support the counterweight 108. In this case, the guide metal 80 supports two sliding members (plunger 82 and counterweight 108) while also supporting one rotating member (gear 71). In this case, by eliminating the support of the counterweight 108 by rolling balls (i.e., using a sliding bearing type), heat generation is more likely, but a significant reduction in the number of parts can be achieved. Alternatively, the vertical positions of the plunger 82 and the counterweight 108 may be swapped, and the gear 71 may be supported by a part that slidably supports the counterweight 108.

[0072] Furthermore, the lower surface 80B of the guide metal 80 is configured as a receiving surface that receives (supports) the gear 71, and is installed on the installation portion 42F of the case body 42. This allows the guide metal 80 to be installed in the inner case 40 with the lower surface 80B of the guide metal 80 that receives the gear 71 as a reference. As a result, the gear 71 and the guide metal 80 can be housed in the inner case 40 while suppressing relative positional misalignment between the gear 71 and the guide metal 80 in the vertical direction.

[0073] Furthermore, as described above, the lower surface 80B of the guide metal 80 is configured as a receiving surface that receives (supports) the gear 71, and the connector 83 of the plunger 82 is inserted into a slit 80A formed in the upper and lower middle part of the guide metal 80. This allows the gear 71 to be positioned adjacent to the lower side of the guide metal 80, while the plunger 82 (connector) is positioned in the upper and lower middle part of the guide metal 80. This contributes to miniaturizing the drive mechanism 70 in the vertical direction.

[0074] Furthermore, the guide metal 80 is positioned above the outer circumference of the gear 71. As a result, when the gear 71 moves upward and is supported by the lower surface 80B of the guide metal 80, the outer circumference of the gear 71 comes into contact with the lower surface 80B of the guide metal 80 and slides along the lower surface 80B of the guide metal 80. This reduces the sliding resistance of the gear 71 when it rotates compared to the case where the entire gear 71 is in contact with the lower surface 80B of the guide metal 80.

[0075] Furthermore, a pair of guide metals 80 are arranged within the case body 42, spaced apart in the left-right direction. This allows the pair of guide metals 80 to movably support both left-right sides of the connector 83 of the plunger 82, and to receive both left-right sides of the gear 71 moving upward. Therefore, the support performance of the guide metals 80 for the connector 83 can be improved, and the gear 71 moving upward can be supported in a balanced manner by the guide metals 80.

[0076] Furthermore, the crankpin 75 of the gear 71 is positioned between a pair of left and right guide metals 80. This allows the crankpin 75 to be positioned between the pair of left and right guide metals 80 even when the gear 71 and the guide metals 80 are positioned adjacent to each other in the vertical direction, thereby transmitting the rotational force of the gear 71 to the connector 83 (plunger 82).

[0077] Furthermore, the ring member 104 in the vibration reduction mechanism 70C is positioned adjacent to the upper side of the guide metal 80, so that the guide metal 80 supports the ring member 104 from below. This allows the downward movement of the ring member 104 to be restricted by utilizing the guide metal 80, which movably supports the plunger 82. Therefore, there is no need to provide a separate member in the vibration reduction mechanism 70C to restrict the downward movement of the ring member 104. Consequently, the increase in the number of parts in the drive mechanism 70 can be further suppressed, and the cost of the electric cutting machine 10 can be reduced. In addition, the miniaturization of the drive mechanism 70 in the vertical direction can be effectively achieved.

[0078] Furthermore, the ring member 104 is connected to the gear 71 by the crank pin 75 of the gear 71. That is, the crank pin 75, positioned between the pair of left and right guide metals 80, can connect the gear 71, the plunger 82, and the ring member 104. Therefore, an efficient arrangement structure can be achieved in the drive mechanism 70, and it can also contribute to making the drive mechanism 70 more compact.

[0079] Furthermore, the guide metal 80 is composed of a single component. This contributes to reducing the cost of the guide metal 80 itself.

[0080] Furthermore, the guide metal 80 is made of sintered material and impregnated with a lubricant. This reduces the sliding resistance when the gear 71, connector 83, and ring member 104 slide against the guide metal 80, as the gear 71, connector 83, and ring member 104 are supported by the guide metal 80. Therefore, for example, the durability of the drive mechanism 70 can be improved. Also, since the gear 71 is supported (in the thrust direction) by the rolling ball 50, the generation of frictional heat due to support can be suppressed, and the durability of the drive mechanism can be improved. In addition, since the downward thrust force acting on the gear 71 is absorbed by the cushioning rubber 50B, the durability of the drive mechanism can be improved. In this embodiment, a rubber cushioning rubber 50B is used as the elastic body, but other materials that are elastically deformable may be used. For example, urethane or a metal spring may be used.

[0081] Furthermore, in the electric cutting machine 10, the inner case 40 is composed of a box-shaped case body 42 that opens upwards and a case cover 44 that closes the opening 42M of the case body 42. The drive mechanism 70 is housed inside the inner case 40 and is positioned so as not to protrude upwards from the opening 42M of the case body 42. Therefore, the case cover 44 can be formed into a flat plate shape with the vertical direction being the thickness direction, thereby closing the opening 42M of the case cover 44. This allows the case cover 44 to be formed by press working (punching) on ​​a metal sheet material. Consequently, the cost of the case cover 44 and the inner case 40 can be reduced compared to, for example, the case cover 44 being made of cast material.

[0082] Furthermore, the case cover 44 is fastened to the case body 42 by fixing bolts BL1 and BL2, and the case body 42 is provided with a fixing sleeve 48 that is fastened together with the case cover 44 to the case body 42. The lower part of the fixing sleeve 48 is fitted into the positioning recess 100A of the base member 100 in the vibration reduction mechanism 70C, and the position of the base member 100 is determined by the fixing sleeve 48. In addition, the stepped portion 48A of the fixing sleeve 48 is positioned adjacent to the upper side of the edge of the positioning recess 100A, and the base member 100 is fixed to the case body 42. In this way, the base member 100 can be fixed to the case body 42 while being positioned by utilizing the fixing bolts BL1 and fixing sleeve 48 used to fix the case cover 44 to the case body 42.

[0083] Furthermore, the base member 100 constitutes a part of the vibration reduction mechanism 70C, and the base member 100 is positioned adjacent to the upper side of the guide metal 80 of the reciprocating mechanism 70B. This allows the base member 100 to restrict the upward movement of the reciprocating mechanism 70B and the gear mechanism 70A. Thus, the base member 100, which is fastened to the case body 42 together with the case cover 44 and the fixing sleeve 48, functions as a stopper member for the gear mechanism 70A and the reciprocating mechanism 70B, thereby maintaining a good housing state of the gear mechanism 70A and the reciprocating mechanism 70B in the case body 42.

[0084] Furthermore, the gear 71 is rotatably mounted at the bottom of the case body 42 with its vertical direction as the axial direction. In addition, a shaft housing portion 42C is provided at the bottom of the case body 42, which connects the inside and outside of the case body 42, and the drive shaft 61 of the motor 60 is housed in the shaft housing portion 42C. This allows the motor 60 to be positioned outside the case body 42 while transmitting power from the motor 60 to the gear 71.

[0085] Furthermore, a motor holding portion 42K extending downward is formed at the rear end of the case body 42, and the motor 60 is held by the motor holding portion 42K. Specifically, a motor bearing 66 that rotatably supports the lower end of the drive shaft 61 of the motor 60 is held by a bearing holder 67, and the bearing holder 67 is fitted into the motor holding portion 42K from below and held by the motor holding portion 42K. This allows the motor 60 to be assembled into a unit with the inner case 40 housing the drive mechanism 70, and the unitized inner case 40 and motor 60 can be assembled into the housing 20. This improves the ease of assembly of the electric cutting machine 10.

[0086] Furthermore, in the reciprocating mechanism 70B, the guide metal 80 is sandwiched vertically between the base member 100 and the mounting portion F of the protruding portion 42D on the case body 42, thereby restricting the vertical movement of the guide metal 80. Also, as described above, the guide metal 80 receives the upward-moving gear 71 and restricts the upward movement of the gear 71. This allows the guide metal 80, which restricts the upward movement of the gear 71, to be fixed to the case body 42 by the base member 100. In other words, the case cover 44, base member 100, and guide metal 80 can be fixed to the case body 42 by the fixing bolt BL1 and fixing sleeve 48, while restricting the upward movement of the gear 71.

[0087] Furthermore, an insertion portion 42J is formed at the front end of the case body 42 through which the output shaft 84 of the plunger 82 is inserted. This allows the front end of the output shaft 84 to be positioned outside the inner case 40, and the blade mounting mechanism 92 to be positioned outside the inner case 40.

[0088] Furthermore, in the vibration reduction mechanism 70C, the counterweight 108 is supported by rolling motion by a first rolling ball 110 and a second rolling ball 114. The second rolling ball 114 is positioned between the counterweight 108 and the case cover 44, and is in contact with both. This allows the case cover 44, which closes the opening 42M of the case body 42, to be used to support the counterweight 108. Thus, this contributes to reducing the number of parts in the vibration reduction mechanism 70C and effectively reduces the cost of the drive mechanism 70. In addition, the balls supporting the counterweight 108 (first rolling ball 110 and second rolling ball 114) are configured to move while rolling so as to move relative to both the counterweight 108 and the guide member 102 in the front-rear direction. Therefore, the generation of frictional heat associated with the reciprocating drive of the counterweight 108 can be suppressed, and the lifespan of the parts can be improved.

[0089] Furthermore, in the inner case 40, the vibration reduction mechanism 70C (counterweight 108) is housed above the reciprocating mechanism 70B (plunger 82). In addition, the inner case 40 is assembled to the housing 20 such that the reciprocating mechanism 70B (plunger 82) is positioned above the vertical center portion 20B1 of the handle housing portion 20B in the housing 20. Specifically, the vertical center portion 20B1 of the handle housing portion 20B is positioned below the axis CL of the output shaft 84 of the reciprocating mechanism 70B. Therefore, during cutting, the operator grips the handle housing portion 20B, which is positioned below the plunger 82, and the vibration reduction mechanism 70C, positioned above the plunger 82, reduces the vibration generated by the plunger 82. As a result, during cutting, the front end of the blade 95 acts to trace an elliptical trajectory when viewed from the left and right directions. Thus, the cutting performance of the electric cutting machine 10 on the material to be cut can be improved. [Explanation of Symbols]

[0090] 10...Electric cutting machine (working machine), 40...Inner case (case), 42F...Motor, 60...Motor, 70...Drive mechanism, 71...Gear (first drive member), 75...Crankpin (connecting part), 80...Guide metal (support member), 80A...Slit (second receiving part), 80B...Bottom surface (first receiving part), 82...Plunger (second drive member), 95...Blade (tip tool), 104...Ring member (third drive member)

Claims

1. A motor having a drive shaft, A drive mechanism connected to the motor, which causes the tip tool to reciprocate in the forward and backward direction, A case housing the aforementioned drive mechanism, Equipped with, The aforementioned drive mechanism is A first drive member, configured as a separate component from the aforementioned drive shaft, is rotated around an axis extending in the vertical direction by the transmission of the rotational force of the aforementioned drive shaft, A second drive member capable of holding the aforementioned tip tool and reciprocating in the front-rear direction by the power of the first drive member, A support member is fixed to the case, and in the vertical direction, a portion of which is positioned between the first drive member and the second drive member, restricting the vertical movement of the first drive member and supporting the second drive member so that it can be driven reciprocally, A work machine that includes the following components.

2. A motor having a drive shaft, A drive mechanism connected to the motor, which causes the tip tool to reciprocate in the forward and backward direction, A case housing the aforementioned drive mechanism, Equipped with, The aforementioned drive mechanism is A first drive member, configured as a separate component from the aforementioned drive shaft, is rotated around an axis extending in the vertical direction by the transmission of the rotational force of the aforementioned drive shaft, A second drive member capable of holding the aforementioned tip tool and reciprocating in the front-rear direction by the motor, A support member that restricts the vertical movement of the first drive member and supports the second drive member so that it can be driven back and forth, It has, The first drive member is positioned on one side of the support member in the vertical direction, The aforementioned support member is A first receiving portion is configured as an opposing surface facing the first driving member and supporting the first driving member, A second receiving portion is configured as a slit that is open in a direction perpendicular to the vertical direction and supports the second drive member, A work machine that includes the following components.

3. The first drive member is positioned on one side of the support member in the vertical direction, The work machine according to claim 1, wherein the support member has a first receiving portion configured as a facing surface opposite to the first drive member and supporting the first drive member, and a second receiving portion configured as a slit open in a direction perpendicular to the vertical direction and supporting the second drive member.

4. The work machine according to claim 1, wherein the first drive member is a gear configured to be rotatable in the vertical direction as an axial direction.

5. The work machine according to claim 4, wherein the support member is arranged opposite to the gear in the vertical direction.

6. The second drive member extends in the front-rear direction, and when the drive mechanism is in operation, the second drive member reciprocates in the front-rear direction. The work machine according to claim 1, wherein the tip tool is connected to one end of the second drive member, and the other end of the second drive member is guided by the support member so as to be movable in the front-rear direction.

7. The second drive member extends in the front-rear direction, The work machine according to claim 1, wherein the drive mechanism has a pair of support members arranged spaced apart in the left-right direction.

8. The first drive member is provided with a connecting portion, The work machine according to claim 7, wherein the connecting portion connects the first drive member and the second drive member to transmit power from the motor to the second drive member and is positioned between the pair of support members in the left-right direction.

9. The drive mechanism has a third drive member that is operated by the power of the first drive member, The aforementioned case houses a counterweight. The third drive member transmits power to the counterweight, causing the counterweight to reciprocate in the forward and backward direction in the opposite phase to that of the second drive member. The work machine according to claim 1, wherein the third drive member is positioned on the opposite side of the support member from the first drive member in the vertical direction, and the support member is operably supported by the third drive member.

10. The first drive member is provided with a connecting portion, The work machine according to claim 9, wherein the connecting portion connects the first drive member and the second drive member to transmit power from the motor to the second drive member, and also connects the first drive member and the third drive member to transmit power from the motor to the third drive member.

11. The work machine according to any one of claims 1 to 10, wherein the support member is configured as a single component.

12. The work machine according to any one of claims 1 to 10, wherein the support member is made of a sintered material and the support member is impregnated with a lubricant.

13. A motor having a drive shaft, A drive mechanism connected to the motor, which causes the tip tool to reciprocate in the forward and backward direction, A case housing the aforementioned drive mechanism, Equipped with, The aforementioned drive mechanism is A first drive member, configured as a separate component from the aforementioned drive shaft, is rotated around an axis extending in the vertical direction by the transmission of the rotational force of the aforementioned drive shaft, A second drive member is capable of holding the aforementioned tip tool and is driven to reciprocate in the front-rear direction by receiving power from the first drive member, The load during operation is transmitted to the first drive member via the second drive member, and when the first drive member moves away from the second drive member in the vertical direction due to the power from the drive shaft, an elastic body is pressed by the first drive member and elastically deformed, A work machine that includes the following components.

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