JP2016101622A - Electric tool and assembling method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric tool and an assembling method thereof, the tool being provided with a small cover supporting a revolving shaft of a motor.SOLUTION: A handle housing 40 includes a cover side handle part 41 made of a non-conductive material, and an opposite cover side handle part 42, both of the covers being combined each other. A screw 32 attaching the cover side handle part 41 to a gear cover 30 made of a non-conductive material is positioned inside a motor housing 20 with respective to a radial direction of the motor housing 20. The motor housing 20 includes a partition wall 29a interposed between a wire 33 and the screw 32.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power tool such as a circular saw having a handle housing having a divided structure, and a method for assembling the power tool.

  A circular saw generally has a structure in which a body with a built-in motor is connected to an upper portion of a base, and a circular saw blade that is rotationally driven by the electric motor protrudes from the bottom surface of the base by a predetermined amount. The workpiece set in the above is processed with the circular saw blade (Patent Document 1 below). In such a circular saw, the rotating shaft and the speed reduction mechanism of the motor are supported by a metal gear cover, and a resin handle housing and a motor housing are fixed to the gear cover by screws or the like.

JP 2012-213829 A

  Conventionally, the handle housing is attached to the gear cover on the outside of the motor housing in the radial direction. For this reason, the gear cover needs to have a screw receiving portion on the radially outer side of the motor housing, and it has been difficult to reduce the size.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a power tool capable of reducing the size of a cover that supports a rotating shaft of a motor, and a method for assembling the power tool.

One embodiment of the present invention is a power tool. This electric tool
A motor having a rotating shaft;
A rotating tool that rotates in response to rotation of the rotating shaft;
A cover that supports the rotating shaft;
A motor housing connected to the cover and covering the motor;
A handle housing located on the outer periphery of the motor housing and connected to the cover;
The handle housing is composed of a cover-side handle portion and an anti-cover-side handle portion that are combined with each other on both sides of the rotating tool.
At least one of the attachment members for attaching the cover side handle portion to the cover is located inside the motor housing with respect to the radial direction of the motor housing.

  The cover and the mounting member may be made of a conductive material, and the motor housing and the handle housing may be made of a non-conductive material.

  The motor housing may be connected to the cover in a state where the cover side handle portion is attached to the cover.

  The anti-cover side handle portion may be fixed to the cover or the cover side handle portion in a state where the motor housing is connected to the cover.

  A control unit supported by the cover-side handle unit and configured to control power supply to the motor; and the motor housing includes a guide unit that draws an electric wire connecting the motor and the control unit from an inner side to an outer peripheral side; The partition part which separates between the said guide part and the said attachment member may be included.

  The guide portion may guide the electric wire in a direction different from a direction in which a grip portion of the handle housing is present.

  Another aspect of the present invention is a method for assembling an electric power tool. In this method, a cover-side handle is attached to a cover having a bearing, a motor housing incorporating a motor is connected to the cover, and an anti-cover-side handle is fixed to the cover or the cover-side handle. The cover side handle portion is attached to the cover at a position inside the motor housing with respect to the radial direction of the motor housing.

  It should be noted that any combination of the above-described constituent elements, or a conversion of the expression of the present invention between systems or the like is also effective as an aspect of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the electric tool which can reduce the size of the cover which supports the rotating shaft of a motor, and the assembly method of an electric tool can be provided.

1 is a front sectional view of an electric power tool 1 according to Embodiment 1 of the present invention. FIG. FIG. 4 is a perspective view for explaining the attachment of the cover side handle portion 41 to the gear cover 30 in the electric power tool 1. FIG. 3 is a perspective view for explaining the attachment of the cover-side handle portion 41 to the gear cover 30 as viewed from a direction different from FIG. 2. The perspective view of the combination body of the gear cover 30 and the cover side handle | steering-wheel part 41. FIG. The right side view. FIG. 3 is an assembly perspective view of the motor housing 20 in the electric tool 1. The perspective view of the motor housing 20. FIG. FIG. 5 is a perspective view for explaining the attachment of the motor housing 20 to the combination shown in FIG. 4. FIG. 4 is a right side view of a combination body of a gear cover 30, a cover side handle portion 41, and a motor housing 20. FIG. 10 is a perspective view for explaining the attachment of the non-cover side handle portion 42 to the combination shown in FIG. 9. FIG. 11 is a perspective view for explaining the attachment of the anti-cover side handle portion 42 to the combination shown in FIG. 9 as seen from a direction different from FIG. 10. The perspective view of the combination of the gear cover 30, the handle housing 40 (the cover side handle part 41 and the anti-cover side handle part 42), and the motor housing 20. The right side view. The right view of the state which removed the motor housing 20 and the half of the handle housing 40 of the electric tool 2 which concerns on Embodiment 2 of this invention, respectively. AA sectional drawing of FIG. The right view which abbreviate | omitted illustration of the internal structure of the half of the handle | housing housing 40 and the motor housing 20 of the electric tool 2. FIG.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are examples, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

Embodiment 1
FIG. 1 is a front sectional view of a power tool 1 according to Embodiment 1 of the present invention. 2 and 3 are perspective views for explaining the attachment of the cover-side handle portion 41 to the gear cover 30 as viewed from different directions in the electric power tool 1. FIG. 4 is a perspective view of a combination body of the gear cover 30 and the cover side handle portion 41. FIG. 5 is a right side view of the same. FIG. 6 is an assembly explanatory perspective view of the motor housing 20 in the electric power tool 1. FIG. 7 is a perspective view of the motor housing 20. FIG. 8 is a perspective view for explaining the attachment of the motor housing 20 to the combination shown in FIG. FIG. 9 is a right side view of the combination of the gear cover 30, the cover-side handle portion 41, and the motor housing 20. 10 and 11 are perspective views for explaining the attachment of the non-cover side handle portion 42 to the combination shown in FIG. 9 as seen from different directions. FIG. 12 is a perspective view of a combination of the gear cover 30, the handle housing 40 (the cover side handle portion 41 and the anti-cover side handle portion 42), and the motor housing 20. FIG. 13 is a right side view of the same.

  The electric tool 1 is a portable cutting machine (portable circular saw), and includes a main body 3 and a base 5. The base 5 is a substantially rectangular plate made of metal such as aluminum. The longitudinal direction of the base 5 coincides with the cutting direction. The bottom surface of the base 5 is a sliding surface with the work material. The main body 3 is supported so as to be tiltable to the left and right with respect to the base 5 by the tilt position adjusting mechanism 6 and to be vertically rotatable with respect to the base 5 by a notch depth adjusting mechanism (not shown).

  The main body 3 includes a motor housing 20, a gear cover 30 as a cover, and a handle housing 40, which are combined and integrated with each other. The motor housing 20 has a bottomed cylindrical shape that covers the motor 10 and the fan 11. A bearing 10 b that supports one end of a rotating shaft (output shaft) 10 a of the motor 10 is held at the bottom of the motor housing 20. The motor 10 is a brushless motor in the illustrated example. The fan 11 can rotate integrally with the rotating shaft 10 a of the motor 10 and generates fan air (cooling air) in the motor housing 20. The fan 11 is provided on the opposite side of the bottom of the motor housing 20 with respect to the motor 10. The fan wind is sucked from the wind window 23 appearing in FIG. A substrate 13 connected to the coil of the motor 10 is provided between the motor 10 and the bottom of the motor housing 20. The substrate 13 includes a plurality of switching elements 14 such as FETs and IGBTs for supplying current to the motor 10, and a hall element that constitutes a rotation detection unit that detects the rotation position of the motor 10 (the rotation position of the rotation shaft 10 a). Etc. are provided. For example, three magnetic sensors 17 are provided around the rotation shaft 10a at intervals of 60 °.

  The gear cover 30 is made of metal such as aluminum (made of a conductive material), and supports the rotation shaft 10a of the motor 10 and a speed reduction mechanism (rotation transmission mechanism) 12 that decelerates the rotation of the rotation shaft 10a. Cover the upper half of the circular saw blade 15 as a tool. A saw cover that covers the upper half of the circular saw blade 15 may be combined with the gear cover 30 as a separate body. The rotation of the motor 10 is decelerated by the reduction mechanism 12 and transmitted to the circular saw blade 15. The protective cover 16 is made of, for example, resin, and is provided so as to be rotatable along the outer edge of the gear cover 30. When the cutting operation is not performed, the lower half of the circular saw blade 15 (projected downward from the bottom surface of the base 5). Cover part) except the front part.

  The handle housing 40 includes a cover-side handle portion 41 and a non-cover-side handle portion 42 made of, for example, resin (made of non-conductive material) combined with each other, and is positioned on the outer periphery of the motor housing 20. The handle housing 40 is also provided with a control circuit storage 48 that appears in FIG. 12 and the like at a position behind the motor housing 20. A control circuit board that controls the rotation of the motor 10 is housed in the control circuit housing section 48. A screw 32 as an attachment member for attaching the cover side handle portion 41 to the gear cover 30 is located inside the motor housing 20 with respect to the radial direction of the motor housing 20. The screw 32 is made of a conductive material.

  As shown in FIGS. 6 to 8, the motor housing 20 includes a first housing member made of, for example, resin (made of non-conductive material) having a mating surface parallel to the rotating shaft 10 a of the motor 10 and combined with each other. 21 and a second housing member 22. Each of the first housing member 21 and the second housing member 22 has a plurality of wind windows 23 that allow the inside of the motor housing 20 to communicate with the outside air, and is preferably molded by molding so as to have a plurality of wind windows 23. Is done. The plurality of wind windows 23 are provided on the bottom side of the motor housing 20 relative to the motor 10 with respect to the direction of the rotation shaft 10a, and between the mating surfaces in the circumferential direction of the motor housing 20 (the direction around the rotation shaft 10a) ( Arranged). In the illustrated example, the plurality of wind windows 23 open at the bottom of the motor housing 20.

  Screw fixing portions for fixing the first housing member 21 and the second housing member 22 to each other are provided on both sides of the plurality of wind windows 23 in the circumferential direction of the motor housing 20. Specifically, the first housing member 21 is provided with two screw holes 25 as shown in FIG. 1, and the second housing member 22 has two screw bosses as shown in FIG. 26 (only one appears in FIG. 6) is provided, and the two screws 27 a shown in FIG. 6 pass through the screw fastening holes 25 and are screwed into the screw bosses 26. Further, the first housing member 21 and the second housing member 22 are fixed to each other by two screws 27b in the middle portion in the length direction, and are screwed to each other at a total of four locations.

  As shown in FIG. 7, the motor housing 20 has a guide portion (groove portion) 28 in the vicinity of the end portion on the gear cover 30 side. The guide portion 28 has a role of drawing the electric wire (lead wire) 33 shown in FIG. 1 from the inner side of the motor housing 20 to the outer peripheral side. The electric wire 33 makes a connection between the substrate 13 in the motor housing 20 and the control unit supported by the cover-side handle portion 41 and a connection between the coil of the motor 10 and the power supply side. The guide portion 28 guides the electric wire 33 toward the side of the motor housing 20 (a direction different from the direction in which the grip portion 49 shown in FIG. 12 of the handle housing 40 exists). As shown in FIG. 1, the motor housing 20 has a fan guide 29 that guides the airflow generated by the fan 11 from the motor 10 side of the fan 11 to the outer periphery side of the fan 11, and the end of the fan guide 29 on the gear cover 30 side. Partition walls (ribs) 29a extending from the portion in the outer diameter direction. The partition wall portion 29 a separates the guide portion 28 and the screw 32. The partition wall portion 29 a is interposed between the electric wire 33 passing through the guide portion 28 and the screw 32, and has a role of ensuring a creepage distance between the electric wire 33 and the screw 32.

  Hereinafter, the assembly flow of the motor housing 20, the gear cover 30, and the handle housing 40 will be described.

  First, as shown in FIGS. 2 and 3, the cover-side handle portion 41 is attached to the gear cover 30 with screws 32. The attachment here is temporary fixing in the assembly process, and the cover-side handle portion 41 is further screwed to the gear cover 30 together with the non-cover-side handle portion 42 later. The screw hole 34 (FIG. 3) of the gear cover 30 that receives the screw 32 and the through hole 43 of the non-cover side handle portion 42 through which the screw 32 passes are positioned inside the motor housing 20 with respect to the radial direction of the motor housing 20 to be attached later. Exists. That is, the attachment (temporary fixing) of the cover side handle portion 41 to the gear cover 30 with the screw 32 is performed at a position inside the motor housing 20 in the radial direction of the motor housing 20. The front end surface of the rib 44 provided around the through hole 43 of the cover side handle portion 41 serves as a contact surface with the partition wall portion 29a of the motor housing 20 (FIG. 1).

  On the other hand, the motor housing 20 is assembled as shown in FIGS. 6 and 7, and the motor housing 20 is assembled as shown in FIG. 8 with respect to the combination of the gear cover 30 and the cover side handle portion 41 shown in FIGS. Are attached (fixed) with four screws 35. Then, the anti-cover side handle portion 42 is attached to the combination of the gear cover 30, the cover side handle portion 41, and the motor housing 20 shown in FIG. 9 with screws 45 and 46 as shown in FIGS. To do). The two short screws 45 shown in FIG. 10 are for attaching the anti-cover side handle portion 42 to the cover side handle portion 41, and the two long screws 46 are the anti-cover side handle portion 42 and the cover side handle. The part 41 is attached to the gear cover 30. Thus, as shown in FIGS. 12 and 13, the assembly of the motor housing 20, the gear cover 30, and the handle housing 40 is completed.

  According to the present embodiment, the following effects can be achieved.

(1) Since the screw 32 for attaching the cover-side handle portion 41 to the gear cover 30 is positioned inside the motor housing 20 with respect to the radial direction of the motor housing 20, the cover-side handle portion 41 is connected to the gear cover 30 outside the motor housing 20 in the radial direction. The gear cover 30 can be downsized as compared with the case where it is attached to the gear. Further, by reducing the size of the gear cover 30 having a large specific gravity, it is advantageous for reducing the weight of the entire power tool.

(2) Since the partition wall 29a of the motor housing 20 is interposed between the screw 32 conducting to the gear cover 30 made of a conductive material and the wire 33 passing through the guide portion 28, the space between the screw 32 and the wire 33 It is possible to secure a large creepage distance and to have an excellent insulating property.

(3) Since the guide portion 28 that pulls out the electric wire 33 from the inner side of the motor housing 20 to the outer peripheral side guides the electric wire 33 to the side of the motor housing 20, the electric wire 33 does not protrude upward from the motor housing 20. For this reason, it is not necessary to provide a space for receiving the electric wire 33 in a portion of the handle housing 40 that is above the motor housing 20, and the height of the handle housing 40 can be suppressed.

Embodiment 2
FIG. 14 is a right side view of the electric power tool 2 according to Embodiment 2 of the present invention in a state where half of the motor housing 20 and the handle housing 40 are removed. 15 is a cross-sectional view taken along line AA in FIG. FIG. 16 is a right side view of the electric power tool 2 with the illustration of the half of the handle housing 40 and the internal configuration of the motor housing 20 omitted. The electric power tool 1 of the first embodiment is AC driving with cords, whereas the electric power tool 2 of the present embodiment is cordless DC driving. The handle housing 40 is provided with a rail portion 51 for mounting a battery pack (not shown), and a terminal portion 52 connected to a terminal of the battery pack. When a user operates a trigger switch (operation switch) 47 provided on the handle housing 40, electric power is supplied to the motor 10 from the attached battery pack. Other points of the present embodiment are the same as those of the first embodiment, and the same effects can be achieved.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  The power tool is not limited to the portable cutting machine (portable circular saw) exemplified in the embodiment, and may be another power tool such as a desktop circular saw. The motor 10 may be a motor with a brush.

1, 2 Electric tool, 3 Main body, 5 Base, 6 Tilt position adjustment mechanism, 10 Motor, 10a Rotating shaft (output shaft), 10b Bearing, 11 Fan, 12 Deceleration mechanism (rotation transmission mechanism), 13 Substrate, 14 Switching element , 15 Circular saw blade, 16 Protective cover, 17 Magnetic sensor (rotation detector), 20 Motor housing, 21 First housing member, 22 Second housing member, 23 Air window, 24 Drain hole, 25 Screw fixing Hole, 26 Screw boss, 27a, 27b Screw, 28 Guide (groove), 29 Fan guide, 29a Bulkhead (rib), 30 Gear cover, 32 Screw (mounting member), 33 Electric wire (lead wire), 34 Screw hole , 35 screws, 40 handle housing, 41 cover side handle, 42 anti-cover side handle, 43 through Through hole, 44 rib, 45,46 screw, 47 trigger switch (operation switch), 48 control circuit storage, 49 gripping part, 50 control part, 51 rail part, 52 terminal part

Claims (7)

A motor having a rotating shaft;
A rotating tool that rotates in response to rotation of the rotating shaft;
A cover that supports the rotating shaft;
A motor housing connected to the cover and covering the motor;
A handle housing located on the outer periphery of the motor housing and connected to the cover;
The handle housing is composed of a cover-side handle portion and an anti-cover-side handle portion that are combined with each other on both sides of the rotating tool.
An electric tool, wherein at least one of attachment members for attaching the cover-side handle portion to the cover is located inside the motor housing with respect to a radial direction of the motor housing.   The power tool according to claim 1, wherein the cover and the mounting member are made of a conductive material, and the motor housing and the handle housing are made of a non-conductive material.   The electric motor according to claim 1, wherein the motor housing is connected to the cover in a state where the cover-side handle portion is attached to the cover.   The electric tool according to claim 3, wherein the anti-cover side handle portion is fixed to the cover or the cover side handle portion in a state where the motor housing is connected to the cover.   A control unit supported by the cover-side handle unit and configured to control power supply to the motor; and the motor housing includes a guide unit that draws an electric wire connecting the motor and the control unit from an inner side to an outer peripheral side; The power tool according to any one of claims 1 to 4, further comprising a partition wall portion that separates the guide portion and the mounting member.   The power tool according to claim 5, wherein the guide portion guides the electric wire in a direction different from a direction in which a grip portion of the handle housing is present.   A method for assembling an electric tool, wherein a cover side handle is attached to a cover having a bearing, a motor housing incorporating a motor is connected to the cover, and an anti-cover side handle is fixed to the cover or the cover side handle. A method for assembling an electric tool, wherein the cover side handle portion is attached to the cover at a position inside the motor housing with respect to a radial direction of the motor housing.

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