JP5582337B2 - Electric tool - Google Patents

Description

  The present invention relates to an electric power tool, and more particularly to a bolt tightening machine for tightening a high tension bolt.

  2. Description of the Related Art Conventionally, in construction of bridges, steel buildings, etc., there is a construction method by friction joining using high tension bolts as a method for joining structural materials. As a tool for fastening the high tension bolt, a bolt fastening machine described in Patent Document 1 is exemplified.

  In the conventional shear wrench 101 shown in FIG. 13, the commutator motor 103 in the motor housing 102 rotates when the power cord 125 is connected to a power source (not shown) and the trigger 121A is pressed. This rotational force is transmitted to the inner socket 161 and the outer socket 163 by the rotational drive transmission mechanism 104, engages with a tip and a nut of a high tension bolt (not shown), and reversely rotates with each other to thereby rotate a high tension bolt (not shown). Conclude.

JP 2004-001233 A

  Since the above-mentioned shear wrench 101 is often used in work at high places, there is a need for downsizing the shear wrench 101. In particular, the protruding portion from the fastening material and the motor housing 102 may interfere with each other because the thickness (stacked thickness) in the extending direction of the output shaft of the commutator motor 103 is large. In that case, the operator has to use the shear wrench 101 tilted from the vertical direction in order to avoid the interference between the protruding portion and the motor housing 102, and the workability has deteriorated.

Then, an object of this invention is to provide the electric tool which reduced the size of the extension direction of a motor housing .

In order to solve the above problems, the present invention provides a motor housing that houses a brushless motor, a handle housing that is connected to the motor housing, and a driving force transmission unit that is connected to the motor housing and is driven by the brushless motor. An electric gear characterized in that a substrate on which a switching element for driving the brushless motor is provided is accommodated between an outer peripheral surface of the motor housing and an inner peripheral surface of the handle housing. Provides tools.

According to the electric tool having such a configuration, a brushless motor that is smaller than the conventional commutator motor is adopted, and the substrate for controlling the brushless motor is arranged on the outer peripheral surface of the motor housing and the inner peripheral surface of the handle housing. By accommodating between the surfaces, the size of the motor housing in the extending direction can be reduced.

Furthermore, it is preferable that the handle housing has a substrate accommodating portion that covers a part of the outer peripheral surface of the motor housing and accommodates the substrate .

Further, one of the motor housing and the handle housing has an intake port and the other has an exhaust port. The motor housing has a passage communicating with a portion of the handle housing that accommodates the substrate, and the brushless Air taken in from the intake port by rotation of a fan attached to the output shaft of the motor flows through the passage so as to cool the brushless motor and the substrate, and is discharged from the exhaust port. It is preferable to be configured .

  According to the electric tool having such a configuration, the vibration transmitted to the substrate can be reduced because the brushless motor that generates vibration and the output unit and the substrate are housed in separate housings.

  The present invention also includes a housing, a motor housing extending in one direction from the housing, a brushless motor having an output shaft housed in the motor housing and extending in the one direction, housed in the housing, A driving force transmission portion that extends in a direction intersecting with one direction and is driven by the output shaft of the brushless motor and an end portion of the housing in the extending direction of the driving force transmission portion, and is rotated by the driving force transmission portion. An output portion to be driven, a handle portion extending in one direction from the housing and positioned on a side opposite to the output portion with respect to the motor housing, and in the handle portion for controlling the brushless motor, There is further provided a power tool comprising a substantially rectangular substrate disposed at an end portion of the handle portion in the extending direction.

According to the electric tool having such a configuration, a brushless motor that is smaller than a conventional commutator motor is employed, and a base for controlling the brushless motor is disposed at one end of the handle portion. Therefore, the size of the motor housing in the extending direction can be reduced, and the motor housing can be prevented from coming into contact with a protrusion from the workpiece.

  Further, a power cable for driving the brushless motor is connected from the end surface in one direction of the handle portion, and a trigger switch for switching between supply and cut-off of power to the brushless motor is provided in the handle portion. Preferably, the motor housing and the handle portion are connected at the one-way end.

  According to the electric tool having such a configuration, the power cable is connected to one end surface of the handle portion, the trigger switch is provided in the handle portion, and the motor housing and the handle portion are connected at one end portion. Therefore, the brushless motor, the trigger switch, and the power cable are positioned in the vicinity of the substrate, and wiring in the handle portion and the motor housing can be efficiently performed.

According to the electric tool of the present invention, it is possible to provide an electric tool in which the size of the motor housing in the extending direction is reduced.

The side sectional view of the bolt bolting machine concerning a 1st embodiment of the present invention. FIG. 2 is a partial cross-sectional view of the vicinity of a socket portion that is a bolt fastening machine according to the first embodiment of the present invention and is fitted with a high-tensile bolt. FIG. 3 is a partial cross-sectional view in the vicinity of a socket portion in a state in which a high-tensile bolt is tightened in the bolt fastening machine according to the first embodiment of the present invention. 1 is a front view of a bolt fastening machine according to a first embodiment of the present invention. Sectional drawing along the VV line | wire of FIG. 1 of the bolt fastening machine which concerns on the 1st Embodiment of this invention. The side sectional view of the bolt bolting machine concerning a 2nd embodiment of the present invention. The side view of the bolt fastening machine which concerns on the 2nd Embodiment of this invention. The front fragmentary sectional view of the bolt fastening machine which concerns on the 2nd Embodiment of this invention. The front view of the bolt fastening machine which concerns on the 2nd Embodiment of this invention. The bottom view of the bolt fastening machine which concerns on the 2nd Embodiment of this invention. The side surface fragmentary sectional view of the bolt fastening machine which concerns on the 3rd Embodiment of this invention. The front view of the bolt fastening machine which concerns on the 3rd Embodiment of this invention. Sectional drawing of the conventional bolt fastening machine.

  A power tool according to a first embodiment of the present invention will be described with reference to FIGS. Hereinafter, an example of the electric tool will be described based on a bolt fastening machine. A shear wrench 1 serving as a bolt tightening machine includes a housing 2, a brushless motor 3, a rotational drive transmission mechanism 4, a bolt chip discharge mechanism 5, and a socket portion 6.

  The housing 2 forms an outline of the shear wrench 1 and mainly includes a motor housing 2A, a gear case 2B, and a handle housing 2C. The motor housing 2A is configured to extend from the gear case 2B in a direction substantially orthogonal to the longitudinal direction of the gear case 2B. Hereinafter, the direction in which the motor housing 2A extends from the gear case 2B is defined as a downward direction, and the opposite side is defined as an upward direction. The longitudinal direction of the gear case 2B and the direction in which the socket portion 6 is provided with respect to the gear case 2B is defined as the front direction, and the opposite side is defined as the rear direction. The vertical direction and the direction orthogonal to the front-rear direction (direction orthogonal to the paper surface of FIG. 1) are defined as the left-right direction.

  The motor housing 2A is composed of a cylindrical resin member extending in the up-down direction, and has a first exhaust port 2b formed in the upper portion and a plurality of intake ports 2a formed in the lower portion. The motor housing 2A extends downward from the gear case 2B on the front side of the handle housing 2C, and the brushless motor 3 is built in the motor housing 2A. The brushless motor 3 mainly includes a rotary shaft 31 extending in the vertical direction, a cooling fan 32, a control board 33, a rotor 35, and a stator 36. The cooling fan 32 is coaxially fixed on the rotating shaft 31. The control board 33 is provided below the brushless motor 3, and a hall element 33 </ b> A for detecting the position of the rotor 35 is provided on the control board 33. An output shaft 31A extending upward is provided at the tip of the rotating shaft 31, and a pinion gear 31B is formed on the output shaft 31A. The rotating shaft 31 is rotatably supported by the motor bearing 34.

  As shown in FIG. 5, the rotor 35 is coaxially fixed to the rotating shaft 31, and four permanent magnets 35A are provided. The stator 36 is supported by a plurality of ribs provided on the inner peripheral surface of the motor housing 2A, and has six coils 36A. A gap 36a is formed between the coils 36A. A gap 36b is also formed between the outer peripheral surface of the stator 36 and the motor housing 2A. As the cooling air from the cooling fan 32 flows through the gap 36a and the gap 36b, the brushless motor 3 is cooled.

  The gear case 2B is made of aluminum (made of metal), and includes a rotational drive transmission mechanism 4, a bolt chip discharge mechanism 5, and the like. The rotational drive transmission mechanism 4 extends in the front-rear direction and includes a gear mechanism 7 and a planetary gear mechanism 8. A rod cover 24 is disposed at a rear portion in the gear case 2B. The rod cover 24 is formed with an insertion hole 24a through which a rear end portion of a rod 51 described later is inserted in the front-rear direction. The insertion hole 24a is formed so that its inner diameter is slightly larger than the outer diameter of the rod 51 described later. As shown in FIG. 4, the gear case 2 </ b> B and the motor housing 2 </ b> A are fixed to each other with screws (screws) 29.

  The gear mechanism 7 is interposed between the planetary gear mechanism 8 and the brushless motor 3, and includes a first gear 71 that meshes with the pinion gear 31B, a second gear portion 72 that meshes with the first gear 71, and a second gear. It is mainly composed of a third gear portion 73 that meshes with the portion 72. The first gear 71 is a flat gear, has a rotation shaft parallel to the rotation shaft of the rotation shaft 31, and is rotatably supported by the housing 2. The second gear portion 72 is a flat gear, and has a second gear 72A that meshes with the first gear 71 and a first bevel gear 72B that rotates coaxially with the second gear 72A. The rotation shaft of the second gear portion 72 is parallel to the first gear 71 and is rotatably supported by the housing 2 via a bearing. Further, the second gear portion 72 has a hole through which a later-described plate rod 55 is inserted vertically. The third gear portion 73 is a bevel gear, a second bevel gear 73A that meshes with the first bevel gear 72B, and is positioned on the front side of the second bevel gear 73A and coaxially rotates with the second bevel gear 73A. A first sun gear 73B. The third gear portion 73 is rotatably supported on the rod cover 24 via a bearing. The third gear portion 73 is formed with a through-hole penetrating in the front-rear direction at the center of the rotation axis, and a rod 51 described later is inserted therein.

  The planetary gear mechanism 8 includes a first planetary gear 81, a second planetary gear 82, a third planetary gear 83, and an outer peripheral portion 8A that is a ring gear of the first to third planetary gears 81 to 83. The first planetary gear 81 is disposed in front of the third gear portion 73, revolves with the first sun gear 73B as a sun gear and the outer peripheral portion 8A as a ring gear, and decelerates the rotation of the first sun gear 73B and outputs it. A second sun gear 81A. The second planetary gear 82 is disposed in front of the first planetary gear 81, revolves with the second sun gear 81A as a sun gear and the outer peripheral portion 8A as a ring gear, and decelerates and outputs the rotation of the second sun gear 81A. A third sun gear 82A. The third planetary gear 83 is disposed in front of the second planetary gear 82 and revolves with the third sun gear 82A as a sun gear and the outer peripheral portion 8A as a ring gear. The rotation of the third sun gear 82A is reduced and output. Output part 83A.

  The output portion 83A is open at the front end, and has a socket accommodating space 83a in which an inner socket 61 described later can be accommodated and a weight 52 described later is accommodated. On the inner periphery of the socket housing space 83a, a spline receiving portion 83B configured by a plurality of concave portions extending in the front-rear direction is provided. On the inner periphery, a ball receiving portion 83b capable of receiving a presser ball 61C described later is formed at the front end portion. The first to third planetary gears 81 to 83 each have a through-hole penetrating in the front-rear direction. The through-hole of the third planetary gear 83 opens into the socket housing space 83a, and the first planetary gear 81 The rear end of each through hole opens to the front end side of the first sun gear 73 </ b> B and communicates with the through hole of the third gear portion 73.

  The outer peripheral portion 8A has gears that mesh with the first to third planetary gears 81 to 83, and is supported by the third planetary gear 83 via bearings. Therefore, the outer peripheral portion 8A can rotate with respect to the housing 2 and cannot move back and forth.

  The bolt tip discharge mechanism 5 mainly includes a rod 51, a weight 52, a weight biasing spring 53 that biases the weight 52 forward, a spring 54, a plate rod 55, and a plate 56. The rod 51 has a rod shape whose outer diameter is substantially smaller than that of the insertion hole 24 a, and the tip is fixed to the weight 52. A concave portion 51a is formed on the rear end side of the rod 51. A rear end including the concave portion 51a is a through hole formed in the first to third planetary gears 81 to 83 from the socket accommodating space 83a, and the third gear portion 73. Is disposed in the insertion hole 24a, penetrating through the through-hole formed in the insertion hole 24a. The weight 52 includes a seat portion 52A that receives the weight biasing spring 53, and a biasing portion 52B that is positioned at the front end of the seat portion 52A and forms the tip of the rod portion, and is disposed in the socket housing space 83a. Has been. The weight urging spring 53 is disposed in the socket accommodating space 83a, the front end is seated on the seat portion 52A, and the rear end is seated on the rear end surface of the socket accommodating space 83a to urge the weight 52 to the front side. .

  The spring 54 located behind the gear case 2B is supported by the rod cover 24. The plate rod 55 is formed in a rod shape, and is disposed in the hole formed in the second gear portion 72 with the longitudinal direction being the vertical direction. The upper end can be in contact with one end of a plate 56 described later, and the lower end Is arranged at a position where it can come into contact with a lever 23 described later.

  The plate 56 is provided between the spring 54 and the plate rod 55 and is urged downward by the spring 54. A through hole 56a slightly larger than the insertion hole 24a is formed in the plate 56, and the rod 51 can be inserted therethrough. In the state shown in FIG. 1 (the lever 23 is not rotated), the center of the through hole 56a is off the center of the insertion hole 24a, and a part of the plate 56 closes a part of the insertion hole 24a. In this state, the lever 23 is pulled and rotated upward, whereby the plate rod 55 is pushed by the lever 23 and moves upward, and the plate 56 moves upward against the spring 54. As the plate 56 moves upward, the center of the through hole 56a coincides with the center of the insertion hole 24a.

  The socket portion 6 mainly includes an inner socket 61, a socket biasing spring 62, and an outer socket 63. The inner socket 61 includes a spline portion 61A, a chip urging portion 61B, and a pressing ball 61C, and is configured to be accommodated in the socket accommodating space 83a. A chip holding space 61 a is formed in front of the inner socket 61. A step portion that comes into contact with an inner socket restricting member 63A described later is provided at a substantially central position in the front-rear direction on the outer peripheral surface of the inner socket 61.

  As shown in FIG. 2, the tip holding space 61a is configured to open at the front end of the inner socket 61 to receive and hold the bolt tip 11A (bolt tip) of the high tension bolt 11, and the bolt tip 11A on the inner peripheral surface. A spline groove that fits with the spline shape is formed. Therefore, the inner socket 61 and the bolt tip 11A can rotate together. In the inner socket 61, an opening 61b through which the urging portion 52B of the weight 52 penetrates and protrudes into the chip holding space 61a is formed at the bottom surface of the chip holding space 61a. In the inner socket 61, a seat portion receiving space 61c capable of receiving the seat portion 52A of the weight 52 is formed behind the opening 61b.

  The spline portion 61A is provided on the rear end side of the outer periphery of the inner socket 61, and is engaged with the spline receiving portion 83B in the socket accommodating space 83a. Accordingly, the inner socket 61 can move back and forth with respect to the output portion 83A and cannot rotate, and the inner socket 61 rotates integrally with the output portion 83A.

  The chip urging portion 61B is composed of a ball disposed in a hole opened in the inner peripheral surface of the chip holding space 61a and a spring that urges the ball. When the ball is biased by a spring and protrudes into the chip holding space 61a, the bolt chip 11A can be held in contact with the bolt chip 11A housed in the chip holding space 61a.

  The presser ball 61C is disposed so as to be movable in the vertical direction in a hole penetrating the outer peripheral surface of the inner socket 61 and the inner peripheral surface of the seat portion accommodating space 61c. In a state where the seat portion 52A is accommodated in the seat portion accommodation space 61c, a configuration is adopted in which the pressing ball 61C contacts the outer periphery of the seat portion 52A and protrudes from the outer peripheral surface of the inner socket 61. Accordingly, when the seat portion 52A is positioned in the seat portion accommodating space 61c with the inner socket 61 positioned in front of the output portion 83A (the state shown in FIG. 1), a part of the holding ball 61C is the outer peripheral surface of the inner socket 61. It protrudes further and is inserted into the ball receiving portion 83b. Even if the inner socket 61 is to be inserted into the socket accommodating space 83a in this state, a part of the holding ball 61C received by the ball receiving portion 83b is caught by the spline receiving portion 83B, so that the inner socket 61 is moved backward. It is regulated (state shown in FIG. 3). By retracting the seat 52A from the seat receiving space 61c, the holding ball 61C can protrude into the seat receiving space 61c and can be retracted from the ball receiving portion 83b, so that the inner socket 61 can move backward. It becomes possible (state shown in FIG. 2).

  The socket urging spring 62 is accommodated in the socket accommodating space 83a in a state where the weight 52 and the weight urging spring 53 are accommodated therein. The socket biasing spring 62 is configured such that the front end abuts on the inner socket 61 and the rear end abuts on the rear end surface of the socket accommodating space 83a. The inner socket 61 is biased forward by the socket biasing spring 62.

  The outer socket 63 is attached to the front end portion of the outer peripheral portion 8A, rotates integrally with the outer peripheral portion 8A, forms a nut holding space 63a, and includes an inner socket restricting member 63A. The nut holding space 63a is open to the front end of the outer socket 63 and can be engaged with the nut 12 inside. Therefore, the outer socket 63 and the nut 12 can rotate together. The inner socket restricting member 63A is defined at the position of the rear end surface of the nut holding space 63a, and has an opening 63b through which only the front end portion of the inner socket 61 can be inserted. In a state where the front end portion of the inner socket 61 passes through the opening 63b, the stepped portion of the inner socket 61 contacts the inner socket restricting member 63A. Therefore, the inner socket 61 is attached to the socket biasing spring 62 by the inner socket restricting member 63A. This prevents the nut from falling into the nut holding space 63a.

  The handle housing 2C is a split housing that is divided into two from the center in the left-right direction, and the left and right handle housings are configured to be symmetrical with respect to the one-dot chain line in FIG. The handle housing 2C has a substantially U-shaped cross section, and is fixed to the gear case 2B with screws (screws) 26 at the upper portion and fixed to the lower end portion of the motor housing 2A with screws (screws) 27 at the lower portion. Further, it is fixed to the handle housing 2 </ b> C that is divided in half by screws (screws) 28 on the opposite side in the left-right direction. A circuit board housing space 2c is formed in the handle housing 2C, and a circuit board 22 for controlling the brushless motor 3 is disposed in the circuit board housing space 2c. Inside the handle housing 2C, a passage 2d that connects the space in which the cooling fan 32 is accommodated and the circuit board accommodation space 2c is formed. A plurality of second exhaust ports 2e are formed on the rear surface of the handle housing 2C, and the cooling air from the cooling fan 32 is discharged to the outside through the passage 2d. The handle housing 2C is provided with a trigger 21 for switching the supply of power to the brushless motor 3, and a power cord 25 connected to an external power source (not shown) extends from the lower part.

  The circuit board 22 is disposed at an end portion on the opposite side to the side where the front-rear socket portion 6 in which the rotational drive transmission mechanism 4 extends is provided. The circuit board 22 is substantially rectangular and extends vertically and horizontally, and is supported by a support portion 2F protruding from the inner surface of the handle housing 2C and a rib (not shown). On the front surface of the circuit board 22, a plurality of switching elements 22A and a microcomputer 22B are arranged. The switching element 22A is fixed to the substrate by screws passing through holes (not shown) formed in the substrate. The switching element 22A and the microcomputer 22B are connected to the gear case 2B by a heat transfer member 22C having a high thermal conductivity. Since the heat generated by the switching element 22A and the microcomputer 22B is transmitted to the gear case 2B via the heat transfer member 22C, the cooling efficiency of the switching element 22A and the microcomputer 22B can be increased.

  A lever 23 is disposed in the passage 2d, and a part of the lever 23 projects outside the handle housing 2C. The lever 23 is for operating the bolt tip discharge mechanism 5 and is rotated upward by being pulled by an operator to move the plate rod 55 upward against the urging force of the spring 54. .

  Next, the operation of tightening the high tension bolt 11 of the shear wrench 1 will be described. When the high tension bolt 11 and the nut 12 (FIG. 2) are not inserted into the chip holding space 61a and the nut holding space 63a, the inner socket 61 is moved forward by the socket biasing spring 62 as shown in FIG. The front end portion of the inner socket 61 protrudes into the nut holding space 63a. Further, the weight 52 and the rod 51 are urged forward by the weight urging spring 53 so that the seat portion 52A is accommodated in the seat portion accommodating space 61c, and the urging portion 52B protrudes into the chip holding space 61a.

  As shown in FIG. 2, the bolt tip 11A is inserted into the tip holding space 61a and the nut 12 is put into the nut holding space 63a in a state where the high-tensile bolt 11 and the nut 12 are temporarily fixed to the steel plate S as the workpiece. Insert into. By accommodating the bolt tip 11A in the tip holding space 61a, the bolt tip 11A comes into contact with the biasing portion 52B, and the rod 51 and the weight 52 are moved backward against the biasing force of the weight biasing spring 53. As a result, the seat portion 52 </ b> A retreats from the seat portion accommodating space 61 c, so that the inner socket 61 can move rearward with respect to the outer socket 63. In this state, when the nut 12 is inserted into the nut holding space 63a, the nut 12 abuts against the inner socket 61, and the inner socket 61, the weight 52, and the rod 51 are resisted against the biasing force of the socket biasing spring 62. Moves backwards. Along with this movement, the recess 51a located at the rear end portion of the rod 51 is caught in the through hole 56a of the plate 56, and the forward movement of the weight 52 and the rod 51 is restricted.

  By pulling the trigger 21 in this state, the brushless motor 3 is driven and the cooling fan 32 is also rotated. As a result, the cooling air drawn from the air inlet 2a cools the control board 33, the hall element 33A, and the brushless motor 3. A part of the air is discharged to the outside through the first exhaust port 2b, but the remaining cooling air passes through the passage 2d to cool the switching element 22A and the microcomputer 22B on the circuit board 22, and the second exhaust port. 2e is discharged to the outside.

  At the same time, the driving force of the brushless motor 3 is transmitted to the socket portion 6 via the rotational drive transmission mechanism 4 to rotate the inner socket 61 relative to the outer socket 63. Then, the nut 12 is fastened to the high tension bolt 11, and the brushless motor 3 is further driven to shear the bolt tip 11 </ b> A so as to cut from the high tension bolt 11 as shown in FIG. 3. By this shearing, the nut 12 can be fastened to the high tension bolt 11 with a predetermined torque.

  When the shear wrench 1 is removed from the high tension bolt 11 after the nut 12 is fastened to the high tension bolt 11, the inner socket 61 is biased forward by the socket biasing spring 62, but the weight 52 is the recess of the rod 51. Since the forward movement is restricted by 51a being caught in the through-hole 56a, it stops at the same position as the position where the nut 12 is tightened. Therefore, as shown in FIG. 3, a gap is generated between the inner socket 61 and the weight 52. Moreover, since the bolt tip 11A accommodated in the tip holding space 61a is biased by the tip biasing portion 61B, the bolt tip 11A is prevented from falling out of the tip holding space 61a.

  In this state, the lever 23 is pulled, and the plate 56 is moved upward against the urging force of the spring 54, so that the catch between the through hole 56a and the recess 51a is released. The weight 52 momentarily advances by the biasing force of the weight biasing spring 53, the biasing portion 52B contacts the bolt tip 11A in the tip holding space 61a, and the bolt tip 11A is knocked out from the tip holding space 61a. Can be prepared for tightening.

  According to the above-mentioned shear wrench 1, since the circuit board 22 is disposed at the extending direction end of the rotational drive transmission mechanism 4 extending in the front-rear direction, the vertical size (stack thickness) of the shear wrench 1 is reduced. Can do.

  Furthermore, since the switching element 22A and the microcomputer 22B are connected to the aluminum gear box 2B by the heat transfer member 22C, the switching element 22A and the microcomputer 22B can be efficiently cooled.

  Next, a second embodiment of the present invention will be described with reference to FIGS. Since the structure of the rotational drive transmission mechanism 4, the bolt tip discharge mechanism 5, and the socket portion 6 of the shear wrench 201 is the same as that of the shear wrench 1 of the first embodiment, illustration and description are omitted. Further, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  The housing 202 of the shear wrench 201 according to the second embodiment includes a motor housing 202A (FIGS. 8 and 9), a gear case 202B, and a handle housing 202C configured to overlap a part of the motor housing 202A. Is done. Specifically, as shown in FIG. 9, when viewed from the front of the shear wrench 201, the left side surface of the motor housing 202A overlaps the handle housing 202D (the dotted line is the motor housing 202A).

  As shown in FIGS. 8 and 9, the motor housing 202A is configured by a cylindrical resin member extending in the vertical direction as in the first embodiment, and the brushless motor 3 is accommodated therein. A passage 202a that connects the motor housing 202A and the handle housing 202C is formed on the lower surface of the motor housing 202A. A plurality of passages 202 a are formed side by side in the circumferential direction of the rotating shaft 31 of the brushless motor 3, and cooling air generated by the rotation of the cooling fan 32 passes therethrough.

  The gear case 202B is made of aluminum and extends in the front-rear direction. A motor housing 202A and a handle housing 202C extend downward from the gear case 202B. Exhaust ports 202b for discharging the cooling air of the cooling fan 32 are formed at the base portion where the motor housing 202A extends from the gear case 202B, for a total of four locations, two on each side (FIGS. 6 and 9). By forming the exhaust ports 202b in the front-rear direction, the exhaust resistance of the cooling fan 32 is reduced and more cooling air can be taken in. The gear case 202B and the motor housing 202A are fixed to each other with screws (screws) 207 (FIG. 6).

  The handle housing 202C is constituted by a split housing that is divided into two from the center in the left-right direction. Specifically, the handle housing 202C is configured by combining a left handle housing 202D on the left side and a right handle housing 202E on the right side (FIG. 9). The left handle housing 202D is formed in a substantially U-shape as shown in FIG. 7, and a circuit board housing portion 202F that covers the left outer peripheral surface of the motor housing 202A is defined in the front portion thereof, and the circuit board housing portion 202F is defined. A handle portion 202G on which the trigger 21 is provided is defined behind. A plurality of air inlets 202c are formed in the circuit board housing portion 202F. As shown in FIG. 8, a substantially rectangular circuit board 222 is arranged in the circuit board housing portion 202 </ b> F so that its extending direction is along the rotation shaft 31 of the brushless motor 3. 7, 9 and 10 indicate the arrangement of the circuit board 222, the switching element 22A, and the microcomputer 22B. As shown in FIG. 8, the switching element 22A and the microcomputer 22B on the circuit board 222 are mounted so that the protruding direction from the board is directed outward in the radial direction of the rotating shaft 31, that is, on the air inlet 202c side of the circuit board 222. It has been. Thereby, since the cooling air from the inlet port 202c directly hits the switching element 22A and the microcomputer 22B, their cooling efficiency can be increased. The wiring extending from the circuit board 222 is connected to the control board 33, a switch mechanism 226 (FIG. 6) described later, and the power cable 25. The circuit board 222 is supported on the left handle housing 202D by a plurality of ribs (not shown).

  A switch mechanism 226 that switches the power source to the brushless motor 3 in conjunction with the depression of the trigger 21 is built in the handle portion 202G. The left handle housing 202D is fixed to the motor housing 202A with screws (screws) 203. The left handle housing 202D is fixed to the right handle housing 202E with a plurality of screws (screws) 204 (FIG. 7), and a gear case with screws (screws) 205 (FIG. 10) and screws (screws) 208 (FIG. 6). 202B is fixed.

  The right handle housing 202E is formed in a substantially L shape, and is configured substantially symmetrically with the handle portion 202G with respect to the alternate long and short dash line in FIG. The right handle housing 202E is fixed to the motor housing 202A by screws (screws) 206, and is fixed to the gear case 202B by screws 205 (FIG. 10).

  Next, the flow of cooling air when the trigger 21 is pressed will be described. When the worker presses the trigger 21, the cooling fan 32 (FIG. 8) rotates. The cooling air taken in from the intake port 202c cools the switching element 22A and the microcomputer 22B on the circuit board 222, passes through the passage 202a, and cools the brushless motor 3. Thereafter, the cooling air is discharged to the outside through the exhaust port 202b.

  According to the shear wrench 201 described above, since the circuit board 222 is arranged along the rotation shaft 31 of the brushless motor 3, the size of the shear wrench 201 in the vertical direction can be reduced.

  Further, the brushless motor 3 is accommodated in the motor housing 202A, the rotational drive transmission mechanism 4 is accommodated in the gear case 202B, and the circuit board 222 is accommodated in the handle housing 202C. As described above, since the brushless motor 3 and the rotational drive transmission mechanism 4 that generate vibration and the circuit board 222 are housed in different housings, vibration transmitted to the circuit board 222 can be reduced.

  Next, a third embodiment of the present invention will be described with reference to FIGS. Since the structure of the rotational drive transmission mechanism 4 of the shear wrench 301, the bolt tip discharge mechanism 5, and the socket part 6 is the same as that of the shear wrench 1 of the first embodiment, illustration and description are omitted. Further, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  The housing 302 of the shear wrench 301 according to the third embodiment includes a motor housing 302A, a gear case 302B, and a handle housing 302C.

  Similar to the first embodiment, the motor housing 302A is formed of a cylindrical resin member extending in the vertical direction, and the brushless motor 3 is accommodated therein (FIG. 11). A passage 302a that connects the motor housing 302A and the handle housing 302C is formed on the lower surface of the motor housing 302A. A plurality of passages 302 a are formed in the circumferential direction of the rotating shaft 31 of the brushless motor 3, and cooling air generated by the rotation of the cooling fan 32 passes therethrough. The motor housing 302A is fixed to the gear case 302B with screws (screws) 306.

  The gear case 302B is made of aluminum and extends in the front-rear direction. A motor housing 302A and a handle housing 302C extend downward from the gear case 302B. At the base portion where the motor housing 302A extends from the gear case 302B, a substantially rectangular front exhaust port 302b for discharging the cooling air of the cooling fan 32 opens forward (FIG. 12). Further, a rear exhaust port 302c is formed at each of the left and right locations behind the front exhaust port 302b (FIG. 11).

  The handle housing 302C is located behind the motor housing 302A and extends downward from the gear case 302B. The handle housing 302C and the motor housing 302A are connected to each other at the end of the motor housing 302A. The handle housing 302C is a split housing that is divided into two from the center in the left-right direction, and the left and right handle housings are configured to be symmetrical with respect to the one-dot chain line in FIG. In the handle housing 302C, a handle portion 302D provided with the trigger 21 and the lever 23, and a circuit board housing portion 302E connected to the handle portion 302D and positioned below the handle portion 302D are defined. The circuit board housing portion 302E is provided so as to be inclined obliquely downward from the front to the rear. A switch mechanism (not shown) is provided inside the handle portion 302D. A plurality of air inlets 302d are formed in the circuit board housing portion 302E. In the circuit board housing portion 302E, a substantially rectangular circuit board 322 is arranged so that its extending direction is orthogonal to the rotation shaft 31 of the brushless motor 3. As shown in FIG. 11, the switching element 22A and the microcomputer (not shown) on the circuit board 322 are attached so that the protruding direction from the board is directed downward and coincides with the vertical position of the air inlet 302d. Yes. Thereby, the cooling air from the air inlet 302d directly hits the switching element 22A and a microcomputer (not shown), so that the cooling efficiency can be increased. The wiring extending from the circuit board 322 is connected to the control board 33, a switch mechanism (not shown), and the power cable 25. The circuit board 322 is supported on the handle housing 302C by ribs 327. The handle housing 302C is fixed to the motor housing 302A by screws (screws) 303, and is fixed to the two handle housings 302C located on the opposite side in the left-right direction by a plurality of screws (screws) 304. Is fixed to the gear case 302B.

  Next, the flow of cooling air when the trigger 21 is pressed will be described. When the operator depresses the trigger 21, the cooling fan 32 rotates. The cooling air taken from the air inlet 302d cools the switching element 22A on the circuit board 322 and a microcomputer (not shown), and cools the brushless motor 3 through the passage 302a. Thereafter, the cooling air is discharged to the outside from the front exhaust port 302b and the rear exhaust port 302c.

  According to the shear wrench 301 described above, since the circuit board 322 is disposed at the end of the handle housing 302C in the extending direction, the size of the motor housing 302A in the vertical direction can be reduced, and the motor housing 302A is processed. It is possible to avoid contact with protrusions from the member.

  Further, a power cable is connected to the end surface of the handle housing 302C in the extending direction, and a switch mechanism (not shown) is provided in the handle portion 302D. The motor housing 302A and the handle housing 302 are connected in the extending direction of the motor housing 302A. Connected to each other at the ends. The brushless motor 3, the control board 336, the switch mechanism (not shown), and the power supply cable 25 are located in the vicinity of the circuit board 322, so that wiring in the handle housing 302C and the motor housing 302A can be performed efficiently.

  The shear wrench according to the present invention is not limited to the embodiment described above, and various modifications are possible within the scope of the gist of the invention described in the claims.

  Further, in the present invention, the position of the circuit boards 22, 222, 322 for controlling the brushless motor 3 is changed in the shear wrench 1, 201, 301. However, the output unit is a power tool other than the shear wrench, such as a hammer drill or a hammer. May be applied to an electric tool in which the rotation axis of the motor extends in the direction intersecting with the output portion. In the case of a hammer or hammer drill, the planetary gear mechanism 8 becomes a cylinder and a piston. A drill bit (tip tool) is detachably fixed to the tip of the cylinder.

  In addition, the power supply to the brushless motor 3 is performed by the power cord 25, but the power may be supplied by a rechargeable battery (battery) that can be repeatedly charged. The storage battery may be disposed below the handle housing 2C.

  In the first embodiment of the present invention, the two exhaust ports, the first exhaust port 2b and the second exhaust port 2e, are formed in the gear case 2B and the handle housing 2C, but only the second exhaust port 2e. It may be. Moreover, you may make it the structure which can block | close either one. In this case, it is preferable to increase the opening of the second exhaust port 2e in consideration of the exhaust resistance of the cooling fan 32.

  The gear cases 2B, 202B, and 302B of the present invention are made of aluminum, but may be made of a metal other than aluminum, for example, an alloy containing iron or stainless steel.

1 .. Shear wrench 2 .. Housing 2 A... Motor housing 2 B... Gear case 2 C.. Handle housing 3.. Brushless motor 4 .. Rotation drive transmission mechanism 5. Gear mechanism 8. ・ Planet gear mechanism 8A ・ ・ Outer peripheral part 11 ・ ・ High tension bolt 11A ・ ・ Bolt tip 12 ・ ・ Nut 21 ・ ・ Trigger 22 ・ ・ Circuit board 22A ・ ・ Switching element 22B ・ ・ Microcomputer 24 ・ ・Rod cover 25 ·· Power cord 26 to 28 · · Screw 31 · · Rotating shaft 31A · · Output shaft 31B · · Pinion gear 32 · · Cooling fan 33 · · Control board 34 · · Motor bearing 35 · · Rotor 35A · · · permanent Magnet 36 ・ ・ Stator 36A ・ ・ Coil 36a ・ ・ Gap 36b ·· Clearance 51 · · Rod 51a · · Recess 52 · · Weight 52A · · Seat 52B · · Energizing portion 53 · · Weight biasing spring 54 · · · Spring 55 · · Plate rod 56 · · Plate 56a · · · Through hole 61 .... Inner socket 61A .... Spline part 61B..Chip urging part 61C..Pressing ball 61a..Chip holding space 61b..Open hole 61c. · · · Outer socket 63A · · Inner socket regulating member 63a · · Nut holding space 63b · · Opening 71 · · First gear 72 · · Second gear portion 72A · · Second gear 72B · · First bevel gear 73 ··· Third gear portion 73A · · Second bevel gear 73B · · First sun gear 81 · · First planetary gear 81A · · Second sun gear 82. Second planetary gear 82A Third sun gear 83 Third planetary gear 83A Output section 83B Spline receiving section 83a Socket housing space 83b Ball receiving section 202 Housing 202A ..Motor housing 202B ..Gear case 202C ..Handle housing 202D ..Left handle housing 202E ..Right handle housing 202F ..Circuit board housing portion 202G ..Handle portion 202a .. Passage 202b .. Exhaust port 202c. Ports 203 to 206, screw 302, housing 302A, motor housing 302B, gear case 302C, handle housing 302D, handle portion 302E, circuit board housing portion 302a, passage 302b, front exhaust port 302 ... rear exhaust outlet 302d ·· intake ports 303 and 304 ... screw

Claims (5)

  A motor housing that houses the brushless motor;
  A handle housing connected to the motor housing;
  A gear case that is connected to the motor housing and accommodates a driving force transmission unit driven by the brushless motor,
  An electric tool characterized in that a substrate provided with a switching element for driving the brushless motor is accommodated between an outer peripheral surface of the motor housing and an inner peripheral surface of the handle housing.   The electric power tool according to claim 1, wherein the handle housing has a substrate housing portion that covers a part of the outer peripheral surface of the motor housing and accommodates the substrate.   One of the motor housing and the handle housing has an air inlet and the other has an air outlet.
  The motor housing has a passage communicating with a portion of the handle housing that accommodates the substrate;
  The air taken in from the intake port by the rotation of the fan attached to the output shaft of the brushless motor flows through the passage so as to cool the brushless motor and the substrate and is discharged from the exhaust port. The power tool according to claim 1, wherein the power tool is configured as described above. A housing;
A motor housing extending in one direction from the housing;
A brushless motor having an output shaft housed in the motor housing and extending in the one direction;
A driving force transmission unit housed in the housing, extending in a direction intersecting the one direction, and driven by the output shaft of the brushless motor;
An output portion provided at an end portion of the housing in the extending direction of the driving force transmission portion and driven to rotate by the driving force transmission portion;
A handle portion extending from the housing in the one direction and positioned on a side opposite to the output portion with respect to the motor housing;
An electric tool comprising: a substantially rectangular substrate disposed in an end portion of the handle portion in the extending direction in order to control the brushless motor. A power cable for driving the brushless motor is connected from the end surface in one direction of the handle portion, and a trigger switch for switching between power supply to the brushless motor and shut-off is provided in the handle portion. The electric power tool according to claim 4 , wherein the motor housing and the handle portion are connected at one end in the one direction.

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