JP5904321B2 - Disk motor and electric working machine equipped with the same - Google Patents

Description

  The present invention relates to a disk motor and an electric working machine including the same.

  A general disk motor has a rotor coil substrate having a coil pattern printed on an insulating substrate, and an output shaft (rotation shaft) that holds the rotor coil substrate, and is rotated by a magnetic field applied to the rotor coil substrate. Output power. Compared to a motor manufactured by winding a copper wire around a magnetic core as a rotor, it is lightweight, low noise, low vibration and high efficiency.

  The output shaft is provided with a boss formed so as to be integrated therewith. The boss part has a cylindrical part fitted to the outer periphery of the output shaft and a flange part extending to the outer peripheral side. The rotor coil substrate is fixed so as to be coaxial with the output shaft and to face one surface of the flange portion of the boss portion through an insulating plate. A commutator substrate that supplies current to the rotor coil substrate is provided on the other surface of the flange portion. Japanese Patent Application Laid-Open Publication No. 2004-228561 shows a similar rotor structure.

JP 2011-135842 A

  The conventional disk motor structure has a problem that the heat dissipation effect is small because the flange portion of the boss portion has a disk shape and the area in contact with the atmosphere is small. Further, the reason why the heat dissipation effect is small is that the surface in contact with the flange portion and the atmosphere (that is, the outer peripheral surface of the flange portion) is a smooth surface, and therefore the effect of stirring the atmosphere is small. A conventional disk motor has a rotational speed of about 5,000 rpm and an output of about 100 W. However, in order to produce various products using the disk motor, it is necessary to further increase the rotational speed and increase the output. At this time, since more heat is generated than the conventional heat generation amount, the conventional exhaust heat method may not cope with the large heat generation.

  The present invention has been made in view of the above background, and an object of the present invention is to provide a disk motor having an improved heat dissipation effect with a simple structure and an electric working machine including the disk motor.

The first aspect of the present invention is a disk motor. This disk motor is electrically connected to an output shaft, a rotor coil substrate having at least one coil disk fixed coaxially with the output shaft and having a coil pattern formed on one side or both sides, and the coil pattern. A commutator substrate that supplies current, a current supply unit that supplies current to the commutator substrate, a magnetic flux generation unit that faces the coil pattern, and the rotor coil substrate are located inside, and the output shaft is rotatable. And a structure for outputting power by rotational movement of the rotor coil substrate,
The output shaft has a flange portion protruding in the radial direction, and a plurality of protrusions protruding in the radial direction are formed on the outer periphery of the flange portion in the circumferential direction, and the flange portion and the plurality of protrusions A concave portion that supports the rotor coil substrate in the axial direction of the output shaft and exposes the surface of the rotor coil substrate is formed between the circumferential directions of the plurality of convex portions .

  In the disk motor, the flange portion may be provided between the commutator substrate and the rotor coil substrate.

In the disk motor, the concave portion may be formed at a position overlapping with the commutator of the commutator substrate.

  In the disk motor, a columnar convex portion extending in a radial direction from the center may be formed on the flange portion.

  Alternatively, a blade-shaped convex portion extending in the radial direction from the center may be formed on the flange portion.

  Furthermore, a V-shaped groove extending in the radial direction from the outer periphery toward the center may be formed in the flange portion.

  A second aspect of the present invention is an electric working machine including the disk motor.

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between methods and systems are also effective as aspects of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the disk motor which improved the heat dissipation effect with the simple structure, and an electric working machine provided with the same are realizable.

The perspective view of the brush cutter as an electrically-driven working machine provided with the disk motor which concerns on the 1st Embodiment of this invention. FIG. 2 is a front sectional view of a drive unit including a disk motor of the brush cutter shown in FIG. 1. Sectional drawing which shows the rotor of the disc motor shown in FIG. The perspective view of the structure which integrated the boss | hub part in which the columnar convex part was formed in the output shaft. The top view of a commutator board | substrate. The perspective view of the structure which is the 2nd Embodiment of this invention, Comprising: The boss | hub part in which another columnar convex part was formed was integrated with the output shaft. The perspective view of the structure which is the 3rd Embodiment of this invention, Comprising: The boss | hub part in which the blade-shaped convex part was formed was integrated with the output shaft.

  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, process, 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 exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  FIG. 1 is a perspective view of a brush cutter 1 according to a first embodiment of the present invention. A brush cutter 1 that is an example of an electric working machine mainly includes a drive unit 2, a pipe unit 4, a handle unit 5, and a power supply unit 6, and includes a cutting blade 7 that is mounted on the drive unit 2. The brush cutting work is performed.

  The power supply unit 6 has a battery 69 serving as a power source in a detachable manner. The pipe part 4 mechanically connects (links) the power supply part 6 and the drive part 2. In addition, wiring (such as the power cable 34 in FIG. 2) that electrically connects the power supply unit 6 and the drive unit 2 is inserted into the pipe unit 4. Power is supplied from the power supply unit 6 to the drive unit 2 through this wiring. The drive unit 2 accommodates the disk motor 3 shown in FIG. 2 inside the head housing 11, and rotationally drives the cutting blade 7 with the power supplied from the power supply unit 6. The configuration of the disk motor 3 will be described later.

  The handle portion 5 is attached and fixed in the middle of the pipe portion 4, that is, between the drive portion 2 and the power supply portion 6. The handle portion 5 is formed by attaching grips 52 to the tips of a pair of arms 51. One grip 52 is provided with a throttle 53. By operating the throttle 53, the power supplied to the drive unit 6 can be adjusted, that is, the rotational speed of the cutting blade 7 can be adjusted. The cutting blade 7 has a substantially disk shape, and a sawtooth is formed on the periphery thereof. Further, a hole (not shown in the figure) to be attached to the output shaft 31 of the disk motor 3 in FIG. 2 is formed at the center of the cutting blade 7.

  The operator operates the brush cutter 1 by adjusting the throttle 53. Thereby, the disk motor 3 rotates, the rotational force is transmitted to the output shaft 31, and the cutting blade 7 rotates. Further, by adjusting the throttle 53, the supply power can be adjusted, that is, the rotational speed of the cutting blade 7 can be adjusted.

  2 is a front sectional view of the drive unit 2 of the brush cutter 1 shown in FIG. 1 (the extending direction of the output shaft 31 is defined as up and down). The drive unit 2 includes a disk motor 3 inside the head housing 11. The head housing 11 has a structure that can be divided into two parts, a cover part 12 and a base part 13, which are fitted together and integrated with screws or the like. The disk motor 3 includes a rotor 30, a stator 40, and a pair of brushes 33.

  The rotor 30 of the disk motor 3 is shown in FIG. The rotor 30 includes an output shaft 31, a commutator substrate 35, a rotor coil substrate 36, a boss portion 37, an insulating plate 38, and an insulating sheet 39.

  The commutator substrate 35 has a substantially disk shape as shown in FIG. 5 and has a commutator segment 351 made of a conductor pattern such as copper formed on the upper surface. The output shaft 31 is coaxially fixed to the output shaft 31 so as to coincide with the axis of the output shaft 31. An insertion hole 35a into which the output shaft 31 and the boss portion 37 integrated with the output shaft 31 are inserted is formed at the center of the commutator substrate 35, and a pin into which the pin 32 is inserted at a predetermined distance from the center. A hole 35b is formed. The pins 32 are provided through the commutator substrate 35, the insulating sheet 39, the insulating plate 38, the insulating sheet 39, the flange portion 37B of the boss portion 37, the insulating sheet 39, the insulating plate 38, the insulating sheet 39, and the rotor coil substrate 36. The commutator substrate 35 and the rotor coil substrate 36 are connected and fixed to each other by pins 32. The output shaft 31 is rotatably supported by bearings 311 and 312 fixed to the cover portion 12 and the base portion 13 of the head housing 2. A male screw 31A is formed at the lower end of the output shaft 31, and the cutting blade 7 is fixed by a fastener (not shown).

  The rotor coil substrate 36 is configured by laminating a plurality of (in the present embodiment, four) coil disks 36A having a substantially disk shape and molding them with resin. The coil disk 36A has a substantially disk shape, and a radial pattern or a coil pattern including a radiation pattern group made of a plurality of conductive materials (such as copper) extending in the radial direction from the center is formed on one side or both sides.

  The pins 32 electrically connect a predetermined commutator segment 351 on the commutator substrate 35 and a predetermined coil pattern of the rotor coil substrate 36, and the necessary number of pins 32 is provided.

  The boss portion 37 is coaxially fixed to the output shaft 31 and includes a substantially cylindrical tubular portion 37A and a substantially disc-shaped flange portion 37B. The flange portion 37B is provided so as to protrude outward in the radial direction from the cylindrical portion 37A. Therefore, the output shaft 31 in which the boss portion 37 is integrated has a flange portion 37B provided so as to protrude in the radial direction. The flange portion 37B is sandwiched from above and below by the insulating plate 38. The flange portion 37B is provided in order to increase the strength of the disk motor 3, and the pin 32 that restricts the movement in the circumferential direction and the vertical direction by passing through each member passes therethrough (however, the pin 32 is provided). And the flange portion 37B are insulated.) The insulating sheet 39 functions as an adhesive sheet for thermocompression bonding, and is provided between the coil disks 36 </ b> A and on both sides of the insulating plate 38.

  The rotor 30 is stacked on the one surface side (upper surface side) of the flange portion 37B of the boss portion 37 in the order of the commutator substrate 35, the insulating sheet 39, the insulating plate 38, and the insulating sheet 39, and the other side of the flange portion 37B. The insulating sheet 39, the insulating plate 38, the insulating sheet 39, and the rotor coil substrate 36 are sequentially stacked on the surface side (lower surface side), and are manufactured by heating and compressing from above and below. That is, the commutator substrate 35 is bonded and integrated on one surface of the flange portion 37B and the rotor coil substrate 36 is bonded and integrated on the other surface by functioning as an adhesive for the insulating sheet 39.

  The stator 40 of the disk motor 3 includes a permanent magnet (field magnet) 41 as a magnetic flux generator, and a lower annular yoke 42 and an upper annular yoke 43 that are soft magnetic bodies.

  The cover 12 of the head housing 2 is provided with a power supply cable 34, a brush 33, and an upper annular yoke 43. The base portion 13 is provided with a permanent magnet 41 and a lower annular yoke 42. A plurality of permanent magnets 41 are arranged at equiangular intervals at positions facing the radial pattern or the radiation pattern group of the coil disk 36A.

  Electric power is supplied to the disk motor 3 from the power supply cable 34, and a current flows from the brush 33 as a current supply unit electrically connected to the power supply cable 34 to the commutator substrate 35. The brush 33 is provided at a symmetrical position with respect to the output shaft 31 and is supported by the cover portion 12. The brush 33 is urged by a spring 33 </ b> A so as to contact the commutator segment 351 on the commutator substrate 35. The upper annular yoke 43 is fixed to the cover portion 12 with screws or the like.

  Holes 131 are formed at equiangular intervals with respect to the output shaft 31 on the upper surface of the base portion 13 of the head housing 2, and the permanent magnets 41 are fitted and fixed in the respective holes 131. Further, the lower annular yoke 42 is disposed in the annular groove 132 formed on the lower surface of the base 13 and is fixed to the base 13 with screws or the like.

  In the present embodiment, there is a feature in the shape of the flange portion 37B of the boss portion 37, and as shown in FIG. 4, on the side surface (that is, the outer periphery) of the flange portion 37B that does not contact the commutator substrate 35 and the coil substrate 36. The columnar convex portions 61 are provided periodically (that is, at equiangular intervals). Thus, by forming the columnar convex part 61 in the outer periphery of the flange part 37B, the contact area of the boss | hub part 37 and air | atmosphere increases, and thermal radiation efficiency improves. In addition, the flow of the air that circulates along the outer periphery of the flange portion 37B is increased as the flange portion 37B rotates as compared with a simple disc-shaped flange portion, and the commutator substrate 35 and the rotor due to this atmospheric flow are increased. A heat radiation effect of the coil substrate 36 and the like can also be expected.

  In the configuration of the disk motor 3 described above, when power is supplied to the commutator segment 351 on the commutator substrate 35 through the path of the power supply unit 6, the feeding cable 34, and the brush 33, the permanent magnet 41 is selectively energized. The disk motor 3 continues to generate rotational torque by electromagnetic force between the coil pattern (radial pattern or radiation pattern group) of the rotor coil substrate 36.

  The heat generated from the rotor coil substrate 36 includes Joule heat generated by the current flowing through the coil pattern. The heat generated from the commutator substrate 35 includes Joule heat generated by current flowing through the commutator segment 351, and frictional heat generated between the commutator segment 351 and the brush 33 and heat generated by sparks. Therefore, a structure capable of efficiently exhausting these heats is necessary. However, in this embodiment, the heat dissipation effect can be improved for the following reasons, and it can cope with further increase in the number of revolutions and output of the disk motor. It becomes possible.

(1) The columnar convex portions 61 are periodically formed on the side surface (that is, the outer periphery) of the flange portion 37B that does not contact the commutator substrate 35 and the coil substrate 36, thereby increasing the contact area between the boss portion 37 and the atmosphere. It is possible to improve the heat dissipation efficiency.

(2) The presence of the columnar convex portion 61 increases the flow of air that circulates along the outer periphery of the flange portion 37B, and the heat dissipation effect of the commutator substrate 35, the rotor coil substrate 36, and the like due to this air flow can also be expected.

(3) Since the commutator substrate 35 is bonded to one surface of the flange portion 37B of the boss portion 37 and the rotor coil substrate 36 is bonded to the other surface, efficient heat removal by heat conduction is possible. .

  FIG. 6 shows a second embodiment of the present invention. In the disk motor 3, the boss portion 37 having a flange portion 37 </ b> B formed with another columnar convex portion 62 is integrated with the output shaft 31. Show. In this case, the columnar convex portions 62 have a shape approximate to the commutator segment 351 on the commutator substrate 35 in FIG. When the flange portion 37 </ b> B and the commutator substrate 35 of FIG. 5 are bonded, the columnar convex portion 62 is disposed at the same position as the commutator segment 351.

  According to the second embodiment, the contact area between the flange portion 37B and the commutator substrate 35 is increased and the adhesive force is further strengthened as compared with the case of FIG.

  The same effect can be obtained by forming V-shaped grooves at equal angular intervals instead of forming the columnar convex portions 62 at equal angular intervals on the outer periphery of the flange portion 37B. Further, the number of the columnar protrusions 62 may be less than that of FIG. 5 as long as the multiple is the number of the commutator segments 351 on the commutator substrate 35. For example, the columnar protrusions 62 are half of the commutator segments 351. Even if it is provided with an arrangement interval twice as large as that of the commutator segments 351, it is possible to increase the contact area and strengthen the adhesive force.

  FIG. 7 shows a third embodiment of the present invention, and the disk motor 3 has a flange portion 37B in which a blade-shaped convex portion 63 is formed instead of the columnar convex portions 61 and 62 of FIGS. A configuration in which the boss portion 37 is integrated with the output shaft 31 is shown. The blade-shaped convex portions 63 are provided at equiangular intervals on the outer periphery of the flange portion 37B.

  According to the third embodiment, the surface area on the outer peripheral side of the flange portion 37B can be increased by the blade-shaped convex portion 63 as compared with FIG. 4 and FIG. Due to the effect of scratching, the heat dissipation effect is further improved compared to the examples of FIGS.

  In each embodiment, the unevenness on the outer periphery of the flange portion due to the provision of the columnar convex portions 61 and 62 and the blade-shaped convex portion 63 is formed at a position overlapping the commutator (commutator) of the commutator substrate 35. Also good. Further, it is desirable that the diameter including the columnar convex portions 61 and 62 and the blade-shaped convex portion 63 of the flange portion 37 </ b> B in each embodiment be as large as possible so as not to contact the inner wall of the head housing 2. Normally, from the viewpoint of miniaturization, the shape does not protrude from the outer peripheral edge of the commutator substrate 35. However, when the heat radiation effect is important, the shape may protrude from the outer peripheral edge of the commutator substrate 35.

  The number of the columnar convex portions 61 and 62 and the blade-shaped convex portion 63 is arbitrary, but since the disk motor 3 is manufactured by heat compression, it is desirable to arrange it isotropically.

  The columnar convex portions 61 and 62 and the blade-shaped convex portion 63 are desirably manufactured by an integral molding method with the flange portion 37B.

  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. For example, in addition to the brush cutter shown in the embodiment, the electric working machine may be various electric tools having a rotary drive unit by a disk motor such as a belt sander or a rotary band saw equipped with a disk motor.

DESCRIPTION OF SYMBOLS 1 Brush cutter 2 Drive part 3 Disc motor 4 Pipe part 5 Handle part 6 Power supply part 7 Cutting blade 11 Head housing 12 Cover part 13 Base part 30 Rotor 31 Output shaft 32 Pin 33 Brush 35 Commutator board 36 Rotor coil board 37 Boss part 37B Flange portion 38 Insulating plate 39 Insulating sheet 41 Permanent magnet 42 Lower annular yoke 43 Upper annular yoke 61, 62 Columnar convex portion 63 Blade-shaped convex portion

Claims (7)

An output shaft;
A rotor coil substrate having at least one coil disk fixed coaxially with the output shaft and having a coil pattern formed on one side or both sides;
A commutator substrate that is electrically connected to the coil pattern and supplies a current;
A current supply unit for supplying current to the commutator substrate;
A magnetic flux generator facing the coil pattern;
A disk motor that includes a housing in which the rotor coil substrate is positioned and rotatably holds the output shaft, and outputs power by a rotational movement of the rotor coil substrate;
The output shaft has a flange portion protruding in the radial direction, and a plurality of protrusions protruding in the radial direction are formed on the outer periphery of the flange portion in the circumferential direction, and the flange portion and the plurality of protrusions A disk motor , wherein the rotor coil substrate is supported in the axial direction of the output shaft, and a recess that exposes the surface of the rotor coil substrate is formed between the circumferential directions of the plurality of protrusions .   The disk motor according to claim 1, wherein the flange portion is provided between the commutator substrate and the rotor coil substrate. Disk motor according to claim 2, wherein said concave portion is formed at a position overlapping with the commutator of the commutator substrate, characterized by.   4. The disk motor according to claim 1, wherein a columnar convex portion extending in a radial direction from the center is formed on the flange portion. 5.   4. The disk motor according to claim 1, wherein a blade-shaped convex portion extending in a radial direction from the center is formed on the flange portion. 5.   The disk motor according to any one of claims 1 to 3, wherein a V-shaped groove extending in a radial direction from the outer periphery toward the center is formed in the flange portion.   An electric working machine comprising the disk motor according to any one of claims 1 to 6.

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