JP2019022939A - Rechargeable reciprocating saw - Google Patents

Abstract

To secure rigidity of a motor housing even when adopting a brushless motor.SOLUTION: A rechargeable reciprocating saw 1 includes: a brushless motor 7; a longitudinal crank mechanism 8 driven by the brushless motor 7; a slider 9 reciprocated by the longitudinal crank mechanism 8; a blade holder 128 linked to the slider 9; an integrally-cylindrical inner motor housing 61 for storing the brushless motor 7; a handle housing 3 linked to the inner motor housing 61; a front housing 5 for storing the longitudinal crank mechanism 8; a battery installation section 29 which is arranged in a lower section of the handle housing 3 and in which a battery pack 6 is installed; and a control circuit board 36 stored in the battery installation section 29. A centrifugal fan 51 is provided on a rotary shaft 48. A board side suction port is formed in the battery installation section 29. Air sucked from the board side suction port sequentially cools the control circuit board 36 and the brushless motor 7 by rotation of the centrifugal fan 51.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a rechargeable reciprocating saw in which a motor serving as a drive source is accommodated in a housing.

  The electric tool includes a motor serving as a drive source in the housing, and drives the tip tool holding portion by the motor. For example, as disclosed in Patent Document 1, this motor is accommodated in a cylindrical motor housing formed by assembling a pair of half housings.

JP 2014-133284 A

  In such an electric tool, when a compact brushless motor is employed as the motor, the motor housing is reduced in size (smaller in diameter). For this reason, if it is a model that generates vibration, such as a reciprocating saw, the motor housing having a halved structure may have insufficient rigidity.

  Therefore, an object of the present invention is to provide a rechargeable reciprocating saw that can ensure the rigidity of a motor housing even when a brushless motor is employed.

In order to achieve the above object, the invention described in claim 1 is a brushless motor having a rotating shaft extending in the front-rear direction, a reciprocating motion conversion mechanism driven by the brushless motor, and a reciprocating motion reciprocating mechanism. A slider, a tip tool holding portion connected to the slider, an integral cylindrical motor housing that houses a brushless motor, a handle housing that is connected to the motor housing, a front housing that houses a reciprocating conversion mechanism, and a lower portion of the handle housing A battery mounting portion on which the battery is mounted, and a control circuit board that is housed in the battery mounting portion and controls the brushless motor, and a fan is provided on the rotating shaft, and the board mounting inlet on the battery mounting portion The air drawn in from the board-side intake port by the rotation of the fan is And characterized by cooling the brushless motor in order.
According to a second aspect of the present invention, in the configuration of the first aspect, a motor side air inlet is formed behind the brushless motor in the handle housing, and the air sucked from the motor side air inlet is a control circuit board. The brushless motor is cooled without cooling the motor.
According to a third aspect of the present invention, in the configuration of the first or second aspect, the handle housing includes a handle upper portion connected to the upper side of the motor housing, a handle lower portion provided with a battery mounting portion, and a lower side of the motor housing from the handle lower portion. A loop type consisting of a handle front portion connected to the handle and a handle rear portion connected to the handle upper portion and the handle lower portion as a grip, and air sucked from the board side intake port passes through the handle front portion. .
In order to achieve the above object, a fourth aspect of the present invention is directed to a brushless motor in which a rotation shaft for rotating a fan extends in the front-rear direction, a reciprocating motion conversion mechanism driven by the brushless motor, and a back-and-forth direction by a reciprocating motion conversion mechanism. A reciprocating slider, a tip tool holding portion connected to the slider, an integral cylindrical motor housing that houses the brushless motor, a loop handle housing that connects to the motor housing, and a front housing that houses the reciprocating conversion mechanism A battery mounting portion that is disposed at a lower portion of the handle housing and in which a battery is mounted; and a control circuit board that is housed in the battery mounting portion and controls the brushless motor. 1 air inlet is formed and the second air inlet The air sucked from the first intake port by the rotation of the fan is introduced into the motor housing through the handle housing, and the air sucked from the second intake port is introduced into the motor through the handle housing. It is introduced into the housing.
According to a fifth aspect of the present invention, in the configuration according to any one of the first to fourth aspects, the battery mounting unit includes one or two batteries.

  According to the present invention, by adopting an integral cylindrical motor housing, rigidity can be ensured even when a brushless motor is employed.

It is a side view of a rechargeable reciprocating saw. It is a rear view of a rechargeable reciprocating saw. It is a top view of a rechargeable reciprocating saw. It is the sectional view on the AA line of FIG. FIG. 4 is a partial cross-sectional view taken along line BB in FIG. 3. It is a longitudinal cross-sectional view of a rechargeable reciprocating saw. It is a side view of the rechargeable reciprocating saw in a state in which the left half housing of the rear housing is omitted. FIG. 8 is a perspective view of a rear housing portion of FIG. 7. It is a disassembled perspective view of a brushless motor and an inner motor housing. It is a longitudinal cross-sectional view of a front housing part. It is CC sectional view taken on the line of FIG. It is the DD sectional view taken on the line of FIG. It is explanatory drawing which shows the example of a change of a battery mounting part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a side view of a rechargeable reciprocating saw (hereinafter simply referred to as “reciprocating saw”) as an example of an electric tool, FIG. 2 is a rear view, and FIG. 3 is a plan view. The housing of the reciprocating saw 1 includes a rear housing 2 having a handle housing 3 at a rear portion and an outer motor housing 4 as a second motor housing at a front portion, and a front housing 5 assembled in front of the rear housing 2. A battery pack 6 serving as a power source is attached to the lower end of the handle housing 3, and a brushless motor 7, which will be described later, is accommodated in the outer motor housing 4 as shown in FIGS. Accommodates a vertical crank mechanism 8 that converts the rotation of the brushless motor 7 into a reciprocating motion of a slider 9 as a reciprocating member extending in the front-rear direction.

  The rear housing 2 is made of a resin in which a pair of half housings 2a and 2b, in which the handle housing 3 and the outer motor housing 4 are integrally formed, are assembled by screws 10, 10,. The outer motor housing 4 is formed in a cylindrical shape having a substantially elliptical cross section. The handle housing 3 is separated from the outer motor housing 4 by a handle upper portion 3a, a handle lower portion 3b, a handle front portion 3c, and a handle rear portion 3d. It is formed in a loop shape that protrudes backward. A switch 11 having a trigger 12 protruding forward is accommodated in the handle rear portion 3d serving as a grip. Reference numeral 11a denotes a trigger signal line that is wired from the switch 11 into the handle rear portion 3d and connected to the controller 33 described later. The handle upper part 3a is provided with a lock-off button 13 that can be slid in the left-right direction, and a window 14 for displaying the position of the lock-off button 13 is provided on the upper surface of the handle upper part 3a. A plurality of slit-shaped first air inlets 15, 15... Are provided in the vertical direction on the left and right sides of the handle front portion 3 c that closes the rear of the outer motor housing 4. Second intake ports 15a and 15a are also provided on the left and right sides of the handle lower portion 3b.

  A concave portion 16 is formed on the upper right side of the outer motor housing 4, and a cylindrical hook receiver 17 extends forward and backward in the concave portion 16 as shown in FIG. It is supported in the front-rear direction by being fixed to an inner motor housing 61 to be described later by two screws 19, 19. A hanging hook 20 formed by bending a metal rod-like body into a U shape is attached to the hook receiver 17. Specifically, one end portion 20 a of the hanging hook 20 is inserted into the hook receiver 17 from the rear, and the retaining pin 21 is passed through the tip protruding from the hook receiver 17 in an orthogonal shape, thereby hanging the hanging hook 20. Is attached to prevent it from coming off. As shown in FIG. 5, a coil spring is provided between the protrusion 22 provided on the front side of the inner periphery of the hook receiver 17 and a stopper 23 externally mounted on the one end 20 a behind the hook receiver 17. In the normal state, the hanging hook 20 is urged to a retracted position where the retaining pin 21 comes into contact with a locking ring 25 fitted to the front end of the hook receiver 17. Reference numeral 26 denotes a protrusion that protrudes from the outer periphery of the one end 20 a and receives the rear end of the coil spring 24.

  A cross-shaped groove 27 for locking the retaining pin 21 in the left and right direction and the up and down direction is formed on the front surface of the locking ring 25, and the hanging hook 20 is shown by a solid line and a two-dot chain line in FIG. Thus, the three positions where the retaining pin 21 is locked in the groove 27 (the housing position where the other end 20b of the hanging hook 20 is on the lower side, the lateral projecting position where the other end 20b protrudes to the right side, etc. Positioning is possible every 90 ° to the upper protruding position where the end 20b protrudes upward. When changing the position, the suspension hook 20 can be rotated to an arbitrary position by pushing the suspension hook 20 forward from the retracted position to release the retaining pin 21 and the retaining ring 25. Can be operated.

  Therefore, the reciprocating saw 1 can be suspended by locking the other end 20b to a locking tool or the like provided on the wall or the like with the hanging hook 20 in the laterally protruding position or the upper protruding position. it can. Since the other end portion 20b is bent at an acute angle so as to approach the one end portion 20a side as it goes forward as shown in FIG. 1, it is difficult to come off in a state of being locked by a locking tool or the like. . Further, the portion near the other end 20b of the hanging hook 20 is bent inward along the side surface of the outer motor housing 4 at the housing position shown by a solid line in FIG. 2 so as not to protrude outward. . As shown in FIG. 3, the entire hanging hook 20 is also accommodated inside the maximum width of the reciprocating saw 1 at the accommodation position and does not protrude. Further, the hanging hook 20 at the housing position is configured to surround the outside of the display area 28 such as a company name logo provided on the side surface of the outer motor housing 4 so as not to hide the display area 28.

The battery pack 6 is mounted on the battery mounting portion 29 formed at the lower end of the handle housing 3 by sliding it from the front. Reference numeral 30 denotes a retaining hook provided on the battery pack 6 to be engaged with the battery mounting portion 29, and 31 is a release button for the hook 30.
As shown in FIGS. 6 to 8, a terminal block 32 that is electrically connected to the mounted battery pack 6 is held in the battery mounting portion 29 in the front-rear direction. Above the terminal block 32 and in the battery mounting portion 29, a controller 33 as a control unit is parallel to the terminal block 32 with a slight space provided by a rib 34 protruding from the inner surface of the handle housing 3. Is retained.

  The controller 33 accommodates a control circuit board 36 on which a switching element for controlling the brushless motor 7 and a microcomputer are mounted in a metal dish-shaped case 35. A groove 37 is formed to increase the contact area with air. Lead wires (shown as simple single lines in FIGS. 7 and 8) 38, 38,... Drawn from the rear upper surface of the control circuit board 36 wrap around from the rear side of the controller 33 and between the terminal block 32 and the controller 33. The lead wires 59 and 60, which will be described later, are drawn out through the space and drawn out from the brushless motor 7. Reference numerals 39, 39,... Are protective caps fitted to the connecting portions between the lead wires 38 and the lead wires 59, 60. By coating the connecting portion of the lead wires including the protective cap 39 with resin, it can be made dustproof and waterproof, and can correspond to the international standard IP56. Reference numeral 40 denotes a capacitor, which is not mounted on the control circuit board 36 here and is supported by the support rib 41 in the handle housing 3 above the controller 33 so as not to obstruct the wiring of the lead wire 38. . The capacitor 40 can also be disposed on the handle front portion 3c. In this way, if the control circuit board is placed under the loop-shaped handle, and capacitors are placed on either the rear or front of the handle to disperse the electrical parts, the space inside the handle can be used effectively, and the handle Increase in size can be suppressed.

As shown in FIGS. 4, 6, and 9, the brushless motor 7 is an inner rotor type including a stator 42 and a rotor 43 inside thereof. First, the stator 42 is formed through a cylindrical stator core 44 formed of a plurality of laminated steel plates, front insulators 45 and rear insulators 46 provided on axially front and rear end surfaces of the stator core 44, and front and rear insulators 45, 46, respectively. .. Have six coils 47 wound around the stator core 44.
The rotor 43 includes a rotating shaft 48 positioned at the shaft center, a substantially cylindrical rotor core 49 which is disposed around the rotating shaft 48 and is formed by laminating a plurality of steel plates, and four permanent members inserted and fixed in the rotor core 49. A centrifugal fan 51 is fixed to the rotary shaft 48 in front of the rotor core 49.

  Further, on the peripheral surface of the front insulator 45, relief recesses 52, 52 are formed at point-symmetric positions, and on the peripheral surface of the rear insulator 46, four notches 53, 53 are formed at equal intervals in the circumferential direction. ing. Further, the rear surface of the rear insulator 46 holds six fusing terminals 54, 54... Fusing the windings between the coils 47, 47, and detects the position of the permanent magnet 50 to detect rotation. A short circuit member 56 including a sensor circuit board 55 on which three rotation detecting elements (not shown) for outputting signals are mounted, and three sheet metal members 57, 57,. Are attached from the rear by screws 58, 58,. 59 is a lead wire that is connected to the sensor circuit board 55 and outputs a rotation detection signal, 60 is a power lead wire connected to each sheet metal member 57, and the lead wires 59 and 60 have the same phase of the stator 42. It is drawn from (here, the lower left side).

The brushless motor 7 is accommodated in an inner motor housing 61 as a first motor housing fixed in the outer motor housing 4. The inner motor housing 61 accommodates the entire stator 42 and a part of the rotor 43 (a rear part including the rotor core 49) and opens the front, and a closing plate 63 that closes the opening of the main body 62. It is an integral cylinder that is not divided into left and right or up and down on a plane in the front-rear direction.
The main body cylinder 62 has a bearing holding portion 64 that holds a bearing 65 that pivotally supports the rear end of the rotary shaft 48 in the center of the rear portion, and suction ports 66, 66. Fixing pieces 68 and 68 projecting from the left and right screw bosses 67 and 67 to which the half housings 2a and 2b are assembled and having through holes 69 are provided at the upper and lower positions on the outer periphery of the main body cylinder 62. When assembling the half housings 2a and 2b, the main body cylinder 62 is fixed by holding the fixing pieces 68 and 68 between the left and right screw bosses 67 and 67. On the left side of the lower fixing piece 68 on the lower surface of the main body cylinder 62, a lead-out port 70 for the lead wires 59 and 60 is formed.

A pedestal 71 is provided on the upper surface of the main body cylinder 62 so as to project forward from the upper fixed piece 68 and have a flat upper surface. The pedestal 71 is exposed to an opening 72 formed in the bottom of the recess 16 of the rear housing 2 in a state assembled to the rear housing 2, and the extension plate 18 of the hook receiver 17 is screwed. In the base 71, a metal plate 73 (FIG. 4) to which the screws 19, 19 are screwed is inserted and held. Reference numeral 74 denotes a through hole formed in the cradle 71 at the screwing position.
Furthermore, a flange portion 75 having a vertically long rectangular shape in front view is projected and formed at the front portion of the main body cylinder 62, and through holes 76 are formed at the four corners of the flange portion 75. A pair of screw receiving portions 77 and 77 opening forward are formed at a phase different from the upper and lower fixing pieces 68 and 68 on the outer periphery of the main body cylinder 62.

In addition, circumferential ribs 78, 78 extending in the circumferential direction are provided on the circumferential surface of the main body cylinder 62 at a predetermined interval in the front-rear direction, and the upper surface of the flange portion 75 has the same height as the cradle 71. The upper ribs 79 and 79 are erected at a predetermined interval in the front-rear direction. As shown in FIG. 4, the circumferential rib 78 and the upper rib 79 are engaged with the inner ribs 80, 80..
A plurality of axial ridges 81, 81... That contact the outer periphery of the stator 42 are provided at predetermined intervals in the circumferential direction inside the main body cylinder 62, and the rear insulator 46 is provided on the inner bottom surface. Are formed with four triangular locking projections 82, 82,... Corresponding to the four notches 53, 53,. Chamfered portions 83 and 83 are formed on the left and right side surfaces of the front portion of the main body cylinder 62.

  The closing plate 63 has a ring shape having a central hole 84 through which the rotor core 49 of the rotor 43 can pass, and chamfered portions 85 and 85 corresponding to the chamfered portions 83 and 83 of the main body cylinder 62 are provided on the left and right outer surfaces. Is formed. A pair of cylindrical portions 86, 86 are formed on the outer periphery of the closing plate 63 toward the rear at positions corresponding to the screw receiving portions 77, 77 of the main body cylinder 62. In addition, a holding boss 87 having a through hole is integrally formed. The pressing boss 87 is used for screwing the closing plate 63, and also has a role of pressing the stator 42 against the rear inner surface of the main body cylinder 62 by contacting the front surface of the stator core 44 at the position of the relief recess 52 of the front insulator 45. Plays.

Therefore, the stator 42 is inserted into the main body cylinder 62 from the front in a phase matching the screw receiving portions 77 and 77 with the lead wires 59 and 60 passed through the lead-out port 70 in advance. Then, the stator 42 is coaxially held by the ridges 81, 81,... In the main body cylinder 62, and the locking projections 82 locked to the notches 53 are brought into contact with the rear surface of the stator core 44 so that the pushing position is set. It is determined. At the same time, rotation is prevented by locking the notches 53 and the locking protrusions 82.
Next, the closing plate 63 is fitted to the opening of the main body cylinder 62 by aligning the position of the chamfered parts 85 and 85 with the chamfered parts 83 and 83 on the main body cylinder 62 side, and the pressing bosses 87 and 87 are escaped. It is made to contact | abut on the front surface of the stator core 44 in the position of the recessed parts 52 and 52. FIG. When the pair of screws 88 and 88 are inserted into the holding bosses 87 and 87 from the front and screwed into the screw receiving portions 77 and 77 of the main body cylinder 62, the stator 42 is accommodated in the inner motor housing 61.

  Then, when the rotor 43 having the bearing 65 attached to the rear end of the rotating shaft 48 is inserted into the inner motor housing 61 from the central hole 84 of the closing plate 63 and the bearing 65 is held by the bearing holding portion 64, the rotor 43 is also The centrifugal fan 51 is accommodated in the inner motor housing 61 except for the front portion. A bearing 89 is mounted in front of the centrifugal fan 51 on the rotary shaft 48, and a stop plate 90 is formed between the bearing 89 and the centrifugal fan 51 so as to penetrate the rotary shaft 48 and form cuts 91 and 91 at the upper and lower ends. Is provided. A pinion 92 is formed at the tip of the rotating shaft 48.

  As shown in FIGS. 10 to 12, the front housing 5 is made of metal in which a left split mold 5a and a right split mold 5b are assembled with left and right screws 93, 93,. A small cylindrical holding portion 94 for holding 48 bearings 89 is formed. Further, on the rear surface of the front housing 5, screw holes 95 and 95 (FIG. 6) corresponding to the notches 91 and 91 of the stop plate 90 are formed vertically, and the four through holes of the flange portion 75 provided in the main body cylinder 62 are formed. Four screw bosses 96, 96,... Corresponding to the holes 76, 76,. Therefore, the tip of the rotary shaft 48 is passed through the holding portion 94, the bearing 89 is fitted into the holding portion 94, the flange portion 75 of the inner motor housing 61 is applied to the rear surface of the front housing 5, and the four screws 97 from the rear. 97 (FIGS. 4, 7, and 8) are screwed into the screw bosses 96, 96,. Then, when the screws 98, 98 are screwed into the screw holes 95, 95 through the notches 91, 91 of the stop plate 90, the inner motor housing 61 is connected to the rear end of the front housing 5, and the pinion 92 of the rotating shaft 48 is moved forward. Project into the housing 5. In this state, the bearing 89 is prevented from coming off the holding portion 94 by the stop plate 90.

  Then, the inner motor housing 61 is set in the left half housing 2a and the fixing pieces 68, 68 are positioned on the screw bosses 67, 67, and the controller 33, the switch 11 and the like are assembled, and the lead wire 38, the lead wire 59, When the wiring is completed by connecting the 60s to each other, the right housing half 2b is covered and screwed with screws 10, 10,..., The rear housing 2 is connected to the front housing 5 via the inner motor housing 61. Concatenated with 99, 99... Are exhaust ports (FIG. 1) that open to the outside of the centrifugal fan 51 on the left and right side surfaces of the front end portion of the outer motor housing 4.

  On the other hand, the left and right split molds 5a and 5b of the front housing 5 are respectively formed with receiving recesses 100 and 101 for receiving the rear crank mechanism 8 and the slider 9, and the assembly surfaces of the left and right split molds 5a and 5b are respectively The seal member 102 is sandwiched except for the through portion of the slider 9. Here, the left split mold 5a is wider in the left-right width than the right split mold 5b, the receiving recess 100 is also formed deeper than the receiving recess 101, and the assembly surface of the left and right split molds 5a, 5b is more than the center in the horizontal direction. Shifted to the right.

  The vertical crank mechanism 8 includes a bevel gear 103 as a crank member that meshes with the pinion 92 of the rotating shaft 48, an eccentric pin 104 that protrudes at an eccentric position of the bevel gear 103, and a balancer 105 that is fixed to the tip of the eccentric pin 104. And a strip-shaped connecting rod 106 connected between the eccentric pin 104 and the rear end of the slider 9. The bevel gear 103 here is rotatably supported via a bearing (needle bearing) 108 on a left and right support shaft 107 that is screwed orthogonally in the accommodation recess 100 of the left split mold 5a and protrudes inward. The vertical arrangement. 109 is a washer for preventing the bevel gear 103 from coming off, and 110 is a bolt for fixing the washer 109 to the tip of the support shaft 107.

  The balancer 105 includes a weight part 111 having a fan shape in a side view and a protruding part 112 protruding from the center of the weight part, and the tip of the eccentric pin 104 is press-fitted into a press-fitting hole 113 provided at the tip of the protruding part 112. Thus, it can rotate integrally with the eccentric pin 104. Reference numeral 114 denotes a through hole formed on the extension of the bolt 110 at the boundary between the weight part 111 and the projecting part 112, and enables the bolt 110 to be rotated by inserting a tool even when the balancer 105 is fixed. It is. Reference numeral 115 denotes a positioning hole provided in the weight portion 111 and used for positioning when the balancer 105 is fixed. The rear end of the connecting rod 106 is connected to the eccentric pin 104 between the bevel gear 103 and the balancer 105 and at a substantially central position in the left-right direction. Thus, the balancer 105 here is supported only by the eccentric pin 104, and is not supported by the right split mold 5b.

  The slider 9 is slidably held in the front-rear direction by a holder 116 held by the left and right split dies 5a and 5b at a position in front of the bevel gear 103 and above the rotation center of the bevel gear 103. The holder 116 is composed of a pair of U-shaped receivers 118 and 118 which are respectively fixed in concave grooves 117 formed in the front-rear direction on the inner surfaces of the left and right split dies 5a and 5b. An upper flange 119 that is short in the front and back direction and a lower flange 120 that is long in the front and rear direction are bent and formed on the upper and lower sides of each receiving metal 118, and a pair of through holes 121 and 121 are formed in the front and rear flanges 119 and 120, respectively. Has been.

  On the inner surfaces of the left and right split molds 5a, 5b, pins 122 are driven into positions corresponding to the front through holes 121 on the upper flange 119 above the concave grooves 117, and positions corresponding to the rear through holes 121. Are formed with screw holes 123, respectively. Conversely, a screw hole 123 is formed at a position corresponding to the front through hole 121 of the lower flange 120 below the concave groove 117, and a pin 122 is driven into a position corresponding to the rear through hole 121. It is. Therefore, by inserting the pin 122 into one through-hole 121 of the upper and lower flanges 119 and 120 and screwing the bolt 124 into the screw hole 123 from the other through-hole 121, each receiver 118 is fixed in the concave groove 117. .

  The connection between the front end of the connecting rod 106 and the slider 9 spans the bifurcated portion 125 and the connecting rod 106 with the front end of the connecting rod 106 positioned between the bifurcated portion 125 formed at the rear end of the slider 9. Thus, the connecting pin 126 is penetrated in the left-right direction. Both ends of the connecting pin 126 are engaged with the tops 127 and 127 fitted to the receivers 118 and 118, respectively, and the slider 9 slides along the receiver 118 with the tops 127 and 127 at both ends. The front part is held by a slider guide 140 provided in the front housing 5 so that the slide in the front-rear direction is guided. At the front end of the slider 9 protruding from the front housing 5, a blade holder 128 is provided as a tip tool holder for mounting a blade (not shown).

  On the other hand, a guide shoe 129 is provided below the slider 9 in the front housing 5. The guide shoe 129 includes a slide bar 130 that is slidably mounted in the front-rear direction, and a shoe 131 that is fixed to the front end of the slide bar 130 orthogonally and through which the blade mounted on the blade holder 128 passes. In the housing 5, the locking plate 133 urged downward by the coil spring 132 is locked by selecting one of the plurality of locking recesses 134, 134... Provided on the upper surface of the slide bar 130, The front / rear position of the shoe 131 can be adjusted. The positioned slide bar 130 is locked by operating a lock shaft 130a provided in front of the locking plate 133.

Reference numeral 135 denotes an illumination LED provided in the upper front portion of the front housing 5, and a rear lead wire (not shown) wired in a long groove 136 formed in the front-rear direction to the left split mold 5 a above the housing recess 100. It is electrically connected to the controller 33 on the housing 2 side.
A cylindrical rubber cover 137 is externally provided on the outer periphery of the front housing 5 from the front. The rubber cover 137 extends until the rear end covers the front end of the outer motor housing 4 of the rear housing 2, and covers a part of the exhaust ports 99, 99 except for the central portion of the left and right side surfaces. Yes. However, the air discharged from the exhaust port 99 is forwarded to the inside of the rubber cover 137 by the front and rear contact ribs 138, 138,... Standing on the inner surface of the rubber cover 137 and contacting the outer surface of the front housing 5. Ventilation passages 139, 139,... That pass through the housing 5 and discharge forward are formed.

In the reciprocating saw 1 configured as described above, when the trigger 12 is pushed in and the switch 11 is turned on, the brushless motor 7 is driven by the power supply of the battery pack 6. That is, the microcomputer of the control circuit board 36 obtains the rotation detection signal indicating the position of the permanent magnet 50 of the rotor 43 output from the rotation detection element of the sensor circuit board 55, acquires the rotation state of the rotor 43, and acquires the obtained rotation. The rotor 43 is rotated by controlling ON / OFF of each switching element in accordance with the state, and passing current to each coil 47 of the stator 42 in order.
Accordingly, the rotating shaft 48 rotates to rotate the bevel gear 103 and the eccentric pin 104 moves eccentrically, whereby the slider 9 reciprocates via the connecting rod 106, and the workpiece can be cut by the attached blade. Become. At this time, the balancer 105 rotates in the reverse direction with respect to the rotation center of the bevel gear 103 in accordance with the reciprocation of the slider 9, thereby suppressing the occurrence of vibration.

  Here, if the slider 9 is temporarily locked due to an excessive load applied to the blade during the cutting operation, the impact causes a shift in the positional relationship between the bevel gear 103 and the balancer 105. However, since the balancer 105 is cantilevered only by the eccentric pin 104 on the left split mold 5a side and not supported by the right split mold 5b, the deviation between the bevel gear 103 and the balancer 105 is reduced. Therefore, the influence on the front housing 5 is suppressed, and abnormal noise and abnormal vibration are less likely to occur.

  On the other hand, when the centrifugal fan 51 rotates together with the rotating shaft 48, outside air is sucked from the first air inlet 15 and the second air inlet 15 a of the handle housing 3, and inside the main body cylinder 62 from the air inlet 66 of the inner motor housing 61. Enter. The air that has entered passes between the coils 47 and 47 inside the stator 42 and between the main body cylinder 62 outside the stator 42, and then is guided to the central hole 84 of the closing plate 63, and the centrifugal fan 51. Are discharged radially from the exhaust port 99. Thus, the closing plate 63 also serves as a baffle plate. The brushless motor 7 is cooled by the air flow. Further, since the air that has entered from the second intake port 15a passes through the controller 33 and flows to the brushless motor 7, the controller 33 can be cooled. Since a part of the air discharged from the exhaust port 99 is discharged forward through the ventilation path 139 in the rubber cover 137 as described above, the front housing 5 is also cooled.

As described above, according to the reciprocating saw 1 of the above embodiment, the balancer 105 is supported only by the eccentric pin 104 in the front housing 5, so that abnormal noise and abnormal vibration are generated regardless of the impact when the slider 9 is locked. Can be suppressed.
In particular, since the balancer 105 is supported by press-fitting the eccentric pin 104, the balancer 105 can be easily attached.

Further, according to the reciprocating saw 1 of the above embodiment, the cylindrical inner motor housing 61 that houses the brushless motor 7, the outer motor housing 4 that covers the inner motor housing 61, and the outer motor housing 4 are formed integrally. Since the handle housing 3 is included, rigidity can be ensured even when the brushless motor 7 is employed. Further, the outer motor housing 4 connected to the inner motor housing 61 can secure a wide display space (display area 28) for a company logo or the like.
In particular, since the wiring outlet 70 is provided in the main body cylinder 62, the wiring to the controller 33 can be easily performed even in the case of the integral cylindrical inner motor housing 61.

The attachment of the balancer is not limited to press-fitting, and the balancer may be attached in combination with a detent by a key connection or the like and a retaining by a pin. The shape of the balancer itself can be changed as appropriate. The crank member includes not only one in which an eccentric pin is directly provided on the bevel gear but also one in which the bevel gear is integrally coupled to a crank shaft provided with the eccentric pin.
Further, the slider holder can be formed by combining a pair of U-shaped receivers as in the above embodiment, or by combining a pair of L-shaped receivers.

  However, in addition to supporting the balancer with only the eccentric pin, the eccentric pin is attached to the balancer even if the pin is press-fitted and fixed to the center of rotation of the balancer with a bearing provided on the inner surface of the housing as in the past. If it is inserted loosely, the impact can be reduced.

Further, the first motor housing that accommodates the brushless motor is not limited to the structure in which the closing plate is attached to the main body cylinder as in the above-described embodiment, and the first motor housing is formed by connecting a plurality of cylinders divided by a plane orthogonal to the axial direction. It doesn't matter. In addition to the forward arrangement in which the rotation axis extends in the front-rear direction, the arrangement may be an oblique direction, an upward direction, a downward direction, or the like depending on the type of the electric tool or the form of the housing. In addition, the first air inlet may be omitted, or the second air inlet may be omitted when the heat generated by the control circuit board is small.
In addition, for example, as shown in FIG. 13, a pair of terminal blocks 32, 32 that are placed sideways on the battery mounting portion 29 may be disposed on the front and rear to mount the two battery packs 6, 6.
In the invention in which the first motor housing is covered with the second motor housing and the invention in which the control unit and the battery mounting unit are provided in the lower part of the handle housing, the power tool is not limited to a reciprocating saw but a screw driver, an electric drill, a hammer drill, or the like. In addition, the invention can be adopted. An AC tool that does not use a battery pack as a power source may be used.

  1 .... rechargeable reciprocating saw, 2. rear housing, 3. handle housing, 4. outer motor housing, 5. front housing, 6. battery pack, 7. brushless motor, 8. vertical crank mechanism , 9 .. Slider, 29 .. Battery mounting part, 33 .. Controller, 36 .. Control circuit board, 42 .. Stator, 43 .. Rotor, 48 .. Rotating shaft, 51 .. Centrifugal fan, 61. Inner motor housing, 62 .. Main body cylinder, 63 .. Closing plate, 68 .. Fixed piece, 70 .. Drawer, 75 .. Flange, 103 .. Bevel gear, 104 .. Eccentric pin, 105. 106 .. Connecting rod, 113 .. Press-fit hole, 116 .. Holder.

Claims (5)

A brushless motor whose rotating shaft extends in the front-rear direction;
A reciprocating motion conversion mechanism driven by the brushless motor;
A slider that reciprocates in the front-rear direction by the reciprocation conversion mechanism;
A tip tool holding portion connected to the slider;
An integral cylindrical motor housing that houses the brushless motor;
A handle housing connected to the motor housing;
A front housing that houses the reciprocating motion conversion mechanism;
A battery mounting portion disposed at a lower portion of the handle housing and mounted with a battery;
A control circuit board accommodated in the battery mounting portion for controlling the brushless motor,
A fan is provided on the rotating shaft, a board side air inlet is formed in the battery mounting portion,
A rechargeable reciprocating saw in which the air sucked from the board-side intake port cools the control circuit board and the brushless motor in turn by the rotation of the fan. A motor side air inlet is formed behind the brushless motor in the handle housing,
2. The rechargeable reciprocating saw according to claim 1, wherein air sucked from the motor side air inlet cools the brushless motor without cooling the control circuit board. 3. The handle housing includes a handle upper portion connected to the upper side of the motor housing, a handle lower portion provided with the battery mounting portion, a handle front portion connected to the lower side of the motor housing from the handle lower portion, the handle upper portion and the handle. A loop type consisting of a handle rear part connected to the lower part and serving as a grip,
The rechargeable reciprocating saw according to claim 1 or 2, wherein air sucked from the board-side intake port passes through the front part of the handle. A brushless motor in which a rotating shaft for rotating the fan extends in the front-rear direction;
A reciprocating motion conversion mechanism driven by the brushless motor;
A slider that reciprocates in the front-rear direction by the reciprocation conversion mechanism;
A tip tool holding portion connected to the slider;
An integral cylindrical motor housing that houses the brushless motor;
A loop-type handle housing connected to the motor housing;
A front housing that houses the reciprocating motion conversion mechanism;
A battery mounting portion disposed at a lower portion of the handle housing and mounted with a battery;
A control circuit board accommodated in the battery mounting portion for controlling the brushless motor,
A first air inlet is formed behind the motor housing in the handle housing;
A second air inlet is formed in the battery mounting portion;
Due to the rotation of the fan, the air sucked from the first air intake port is introduced into the motor housing through the handle housing, and the air sucked from the second air intake port passes through the handle housing. A rechargeable reciprocating saw that is introduced into the motor housing.   The rechargeable reciprocating saw according to any one of claims 1 to 4, further comprising one or two batteries mounted on the battery mounting portion.

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