JP2001025196A - Motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To readily mount a plurality of cores on a rotary shaft, to sufficiently ensure a fixing strength of a rotating direction and a drawing direction of the core and to further laminate the plurality of cores without gaps. SOLUTION: This motor comprises a rotor of a constitution, in which a plurality of cores 3 having holes to be engaged with an outer periphery of a rotary shaft 1 are laminated in the axial direction of the shaft 1, and magnets 13 are fixed to radial outer peripheries of the cores 3, and an exciting coil for rotatably driving the rotor in relation to the magnets 13. The motor further comprises bar-like members 4, each having a collision contact portion 2 to be an axial collision contact when the cores 3 are laminated on the shaft 1, and axially penetrating the laminated plurality of the cores 3 to fix the cores 3 to the collision contact portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor using a rotor having a structure in which a plurality of cores having holes engaging with the outer peripheral surface of a rotating shaft are laminated in the axial direction of the rotating shaft.
In particular, the present invention relates to a technique for improving a state of attachment of a core to a rotating shaft.

[0002]

2. Description of the Related Art Conventionally, when a plurality of cores are laminated on a rotating shaft of a rotor in the axial direction, a method of press-fitting and fixing the cores one by one has been adopted. As an example, Japanese Utility Model
FIG. 9 shows one disclosed in Japanese Patent No. 78158.

FIG. 9A shows a cross section of a rotating shaft 81, and a flat portion 82 parallel to the axis is provided on the outer peripheral surface thereof. FIG.
(B) shows a core 83, and a plurality of protrusions 84 are provided on the inner periphery of a hole that engages with the outer peripheral surface of the rotating shaft 81, the leading ends of which contact the flat portion 82 of the rotating shaft 81. FIG. 9C shows a state in which the core 83 is pressed into the rotating shaft 81. Thus, even if the accuracy such as the surface roughness and the roundness of the outer periphery of the rotating shaft 81 and the inner periphery of the hole of the core 83 is rough, the rotating shaft 81 and the core
Can be accurately press-fitted and fixed.
And the fixing force in the rotation direction of the core 83 can be increased.

As shown in FIG. 10, the rotating shaft 81 is provided with a contact portion 85 which is a contact in the axial direction when the core 83 is press-fitted. The core 83 is laminated.

[0005]

However, the core 8
3 is fixed only by press-fitting, and if a force acts in a direction opposite to the press-fitting direction, the core 83 may fall off from the opposite side of the abutting portion 85.

If the number of cores 83 is increased or the press-fit margin is reduced, a gap is likely to be formed between the cores 83 due to vibrations between the rotating shaft 81 and the cores 83 and the like. It may lead to a falling out.

If the press-fitting margin is increased to cope with the above-mentioned problems, the workability is significantly deteriorated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a motor in which a plurality of cores can be easily mounted on a rotating shaft, a sufficient fixing strength in a rotating direction and a detaching direction with respect to the cores can be secured, and the cores can be stacked without gaps. Is to provide.

[0009]

In order to achieve the above object, according to the first aspect of the present invention, a plurality of cores having holes engaging with the outer peripheral surface of a rotating shaft are laminated in the axial direction of the rotating shaft,
In a motor provided with a rotor having a configuration in which magnets are fixed to the outer periphery in the radial direction of a plurality of cores, and an excitation coil that rotationally drives the rotor in relation to the magnets, the axial direction when stacking the core on the rotation shaft A rod-shaped member having an abutting portion serving as an abutting portion and penetrating a plurality of stacked cores in the axial direction and fixing the plurality of cores to the abutting portion is provided.

According to a second aspect of the present invention, in the motor according to the first aspect, the rod-shaped member includes a holding portion for holding a plurality of laminated cores in opposition to the abutting portion, and a gap between the abutting portion and the holding portion. In this configuration, a plurality of cores stacked in a state where the cores are sandwiched are fixed to the end portions. According to a third aspect of the present invention, in the motor according to the second aspect, a plate member is inserted between the plurality of stacked cores and the holding portion, and the plate member is sandwiched between the abutting portion and the holding portion. The plurality of cores and plate members thus formed are fixed to the end portions.

As described above, according to the present invention, a plurality of cores are laminated on the rotating shaft and fixed to the end formed on the rotating shaft using the rod-shaped member, so that the rotating direction and the removing direction with respect to the core can be performed with a simple operation. Can be sufficiently secured, and the cores can be laminated without gaps.
In particular, by inserting a plate member between the holding portion of the rod-shaped member and the core, a uniform tightening force acts on the core, and the core can be pressed flat to further reduce the gap between the cores, and the rod-shaped member The number can be reduced.

Further, according to the invention described in claim 4, according to claim 1,
In the motor according to any one of the above items (3) to (3), the rod-shaped member is a bolt, and a tap that engages with the bolt is formed at the end. According to a fifth aspect of the present invention, in the motor according to any one of the first to third aspects,
The bar-shaped member is a bolt standing upright from the abutting portion, and the holding portion is a nut engaged with the bolt.

[0013] According to the invention described in claim 6, according to claim 1 of the present invention.
6. In the motor described in any one of the above items 5, a non-circular portion for preventing the core from rotating around the rotation axis is formed on the outer peripheral surface of the rotation shaft and the inner circumference of the hole of the core. Further, claim 7
According to the invention described in the above, in the motor according to any one of claims 1 to 6, the gap between the rotating shaft and the core is filled with an adhesive having elasticity after curing.

[0014]

Embodiments of the present invention will be described below. The motor according to this embodiment is a robot motor for driving an arm or the like of an assembly robot.

FIG. 1 shows a configuration example of a rotating shaft and a core in a rotor of a motor according to a first embodiment of the present invention.
FIG. 1A is a front view of a rotating shaft and a core, and FIG.
FIG. 2B is a partial cross-sectional view taken along the line AA shown in FIG.

The rotary shaft 1 has an abutting portion 2 having a diameter larger than that of the conventional rotary shaft, and a plurality of cores 3 having holes engaging with the outer peripheral surface of the rotary shaft 1 are laminated in the axial direction of the rotary shaft 1. . The core 3 has a plurality (eight in this case) of bolt holes 3a.
The bolt 4 is passed through the bolt hole 3 a, and the tip of the bolt 4 is engaged with a tap 5 provided on the abutting portion 2. Then, by tightening the bolts 4, the laminated cores 3 are integrally brought into contact with the end portions 2.
Fixed to. In addition, the tap 5 is formed in a widened portion of the end portion 2 whose diameter is wider than that of the conventional one.

In this case, the bolt 4 is
Form a tap 5 with which the abutment 2
The bolt 4 erected from above may be passed through the core 3 and a nut may be engaged with the tip of the bolt 4 to fasten the core 3. A ring-shaped magnet 13 is provided around the outer periphery of the core 3.
Is arranged.

FIGS. 2 to 5 are diagrams for explaining a modification of the first embodiment of the present invention. FIG. 2 shows a structure in which a thick plate member 6 is inserted between the head of the bolt 4 and the core 3, and the plurality of laminated cores 3 and plate members 6 are fixed to the end portions 2. By using such a plate member 6, when the bolts 4 are tightened, a uniform tightening force acts on the cores 3, and the cores 3 can be pressed flat to reduce the gap between the cores. Further, since the tightening force on the core 3 becomes uniform, the number of the bolts 4 can be reduced.

In the embodiment described above, the plurality of cores 3 stacked by the bolts 4 can be fixed to the abutting portions 2, so that the cores 3 need not be press-fitted and fixed to the rotating shaft 1 as in the conventional case. Good. That is, the core 3 is
And the workability is better than the conventional press-fitting method. However, since the positions of the bolt holes 3a through which the bolts 4 pass must be matched between the cores 3, as shown in FIG. 3, dowels 7 serving as concave projections are provided on the cores 3, and the dowels 7 are overlapped. The positioning facilitates positioning. The core 3 shown in FIG. 3 is fixed by four bolts 4 arranged at equal intervals, and is positioned and fixed by four dowels 7 arranged at the center between the bolts 4. ing.

The play between the bolt 4 and the bolt hole 3a of the core 3 through which the bolt 4 passes is inevitable. Therefore, when the rotating shaft 1 rotates at high speed, the core 3 may be shifted by an amount of play against the fixing strength in the rotating direction (the tightening force by the bolt 4). In that case, first, the method of press-fitting the core 3 into the rotating shaft 1 as in the prior art is adopted, thereby increasing the fixing strength while facilitating the positioning, and displacing the core 3 due to the play between the bolt 4 and the bolt hole 3a. Can be avoided. FIG.
And a projection 3 formed on the core 3.
The structure press-fitted by b is shown.

As shown in FIG. 5, a non-circular portion 9 is formed in addition to the circular portion 8 on the outer peripheral surface of the rotary shaft 1 and the inner circumference of the rotary shaft hole 3c of the core 3, thereby facilitating positioning. However, the fixing strength in the rotation direction can be increased. Further, by filling the gap between the rotating shaft 1 and the core 3 with an adhesive having elasticity after curing, the fixing strength in the rotating direction can be further increased. The adhesive having elasticity after the curing serves as a buffer between the rotating shaft 1 and the core 3, and can prevent the bolt 4 from loosening due to vibration.

FIGS. 6 and 7 show an example of the configuration of a rotor in a motor according to a second embodiment of the present invention. FIG. 6 is a front view of the rotor, and FIG. 7 is a partial cross-sectional view along AA shown in FIG.

The rotating shaft 1, the abutting portion 2, the core 3, the bolt 4, the tap 5, the dowel 7, and the like correspond to the configuration examples shown in FIGS. 1, 3 and 4, respectively. A plurality of magnets 13 (eight magnets 13 in this embodiment) are fixed using the claws 11 and 12 of the core holding member 10 corresponding to the plate member 6 to form a rotor. Claw 1
Eight pieces are formed respectively, and are arranged so as to press down a thinned portion adjacent to the magnet 13 and to be opposed from both sides in the axial direction. The core 3 is connected to the rotating shaft 1 by press-fitting using the flat portion 1a and the projection 3b, and filling or applying an adhesive having elasticity after curing between the two.

The plurality of magnets 13 are bonded and fixed to the core 3 and then held and fixed by bending the right and left claws 11 and 12 shown in FIG. 7 at right angles so as to face each other. As shown in FIG. 6, each magnet 13 is formed in a columnar body having a straight section on the axial center side and a circular arc on the outer peripheral side, and the outer peripheral faces of adjacent magnets 13 are alternately different. It is magnetized to be a pole. The magnets 13 are arranged adjacent to each other in the circumferential direction via the gaps, and are fixed by filling or applying an adhesive between the gaps and the core 3.

Further, in this embodiment, three tapes are wound around the outer periphery of the rotor to prevent the solidified resin from being broken and scattered and to fix the magnet 13. Then, the winding start and end portions are made into two turns, and the position (winding start and end portion)
Is located between the magnets 13, that is, the portion where the claws 11, 12 are arranged.

The bolt 4 has its head and the core holding member 10
A resin material for screw locking is applied and fixed in between, and a resin material for screw locking is applied and fixed to a tap 5 provided in the abutting portion 2. Further, the bolt 4 is threaded at a tip half of the axial length thereof and is screwed to the tap 5.

FIG. 8 shows an example of a configuration of a main part of a rotor and an exciting coil in a motor according to a third embodiment of the present invention. The rotor includes a rotating shaft 1, an abutment 2, a core 3, a bolt 4, a tap 5, a core holding member 10 having claws 11 and 12, and a plurality of magnets 13. The excitation coil is configured by winding a winding 15 around a stator 14. The rotating shaft 1 is held at both ends by a ball bearing bearing 16 to which an outer ring is fixed (a bearing at the other end is omitted).

Each of the above embodiments is an example of a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications may be made without departing from the spirit of the present invention. It is possible. For example, a plurality of cores 3 to be laminated
Rivets or the like may be used in addition to the bolts 4 as a rod-shaped member for fixing. The position and the number of the non-circular portions 8 formed on the rotating shaft 1 and the core 3 can be arbitrarily selected, such as four places shown in FIG. 4 and two places shown in FIG.

In addition to the method of inserting the cores 3 one by one, the cores 3 are integrally inserted into the rotating shaft 1 by caulking and temporarily fixing the cores 3 using the dowels 7. Alternatively, a method of press-fitting and inserting into the rotating shaft 1 can be adopted. Further, the abutting portion 2 is a conventional abutting portion 8
The diameter of the core 3 is increased by 10 to 30%
May be larger than the diameter of the magnet 13 and smaller than the diameter including the magnet 13.

Further, the magnet 13 may be formed in a ring shape as in the first embodiment, or may be divided into a plurality of magnets 13 for each magnetic pole as in the second and third embodiments.
Alternatively, two semi-circular magnets may be used as a ring-shaped magnet to form a plurality of magnetic poles on each semi-circular magnet. Further, the number may be divided into three or another number instead of two. Furthermore, the core pressing technique of the present invention can be applied to a rotor having no magnet or a rotor having a magnet on the inner periphery of the core.

[0031]

As described above, in the rotor of the motor according to the first aspect, the core is fixed to the end of the rotating shaft with the rod-shaped member, so that the core does not fall off in the axial direction of the rotating shaft. . Further, by increasing the fixing strength of the rod-shaped member, the cores can be laminated without any gap.

Further, the rotor of the motor according to claim 2 is
The fixing strength can be increased by fixing the core between the holding portion formed at one end of the rod-shaped member and the abutting portion while holding the core.

Further, in the rotor of the motor according to the third aspect of the present invention, by inserting the plate member between the holding portion of the rod-shaped member and the core, the core can be uniformly pressed when the rod-shaped member is tightened. it can. Thereby, the gap between the cores can be reduced, and the number of rod-shaped members can be further reduced.

The rotor of the motor according to claim 4 is
With the configuration in which the bolt is engaged with the tap formed at the end as the rod-shaped member, the core can be easily fixed. In the motor rotor according to the fifth aspect, the core can be easily fixed by the configuration in which the nut is engaged with the bolt which is provided upright from the abutting portion as the rod-shaped member.

The rotor of the motor according to claim 6 is
The formation of the non-circular portion can prevent the core from rotating around the rotation axis, so that even if a bolt or the like becomes loose, the effect can be minimized.

Further, the rotor of the motor according to claim 7 is:
By filling the gap between the rotating shaft and the core with an adhesive having elasticity after curing, it is possible to prevent loosening of bolts and the like due to vibration.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams showing a configuration example of a rotating shaft and a core in a rotor of a motor according to a first embodiment of the present invention, wherein FIG. 1A is a front view thereof, and FIG. FIG.

FIG. 2 is a diagram illustrating a modification of the first embodiment of FIG. 1;

FIG. 3 is a diagram for explaining still another modification of the first embodiment in FIG. 1;

FIG. 4 is a diagram for explaining still another modification of the first embodiment in FIG. 1;

FIG. 5 is a diagram illustrating still another modification of the first embodiment in FIG. 1;

FIG. 6 is a front view illustrating a configuration example of a rotor in a motor according to a second embodiment of the present invention.

FIG. 7 is a partial sectional view taken along line AA of FIG. 6;

FIG. 8 is a partial sectional view illustrating a configuration example of a rotor and an exciting coil in a motor according to a third embodiment of the present invention.

9A and 9B are diagrams illustrating a configuration example of a rotating shaft and a core in a rotor of a conventional motor, and FIG. 9A is a cross-sectional view of the rotating shaft.
(B) is a plan view of the core, and (C) is a diagram showing a state where the core is pressed into the rotation shaft.

FIG. 10 is a diagram showing a configuration example of a rotating shaft and a core in a rotor of a conventional motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotary shaft 2 Butt end 3 Core 3a Bolt hole 4 Bolt (bar-shaped member) 5 Tap 6 Plate member 7 Dowel 8 Circular portion 9 Non-circular portion 10 Core holding member (plate member) 11, 12 nail 13 Magnet 14 Stator 15 winding Wire 16 ball bearing bearing

Claims (7)

[Claims] 1. A rotor having a configuration in which a plurality of cores having holes engaged with an outer peripheral surface of a rotating shaft are laminated in an axial direction of the rotating shaft, and a magnet is fixed to a radially outer periphery of the plurality of cores; And an excitation coil that rotationally drives the rotor in relation to the motor, further comprising an abutting portion that abuts in the axial direction when stacking the core on the rotating shaft, wherein the stacked plurality of cores is provided. A motor comprising a rod-shaped member penetrating in an axial direction and fixing a plurality of cores to the abutting portion. 2. The bar-shaped member includes a holding portion for holding the plurality of stacked cores in opposition to the abutting portion, and the plurality of stacked cores are held between the abutting portion and the holding portion. The motor according to claim 1, wherein the core is fixed to the abutting portion. 3. A plurality of laminated cores and a plate member inserted in a state in which a plate member is inserted between the plurality of laminated cores and the holding portion, and sandwiched between the abutting portion and the holding portion. The motor according to claim 2, wherein the motor is fixed to the abutting portion. 4. The motor according to claim 1, wherein the rod-shaped member is a bolt, and a tap is formed at the end of the rod to engage the bolt. 5. The bolt according to claim 1, wherein the rod-shaped member is a bolt erected from the abutting portion, and the holding portion is a nut engaged with the bolt. Motor. 6. A non-circular portion for preventing the core from rotating around the rotation axis is formed on an outer peripheral surface of the rotation shaft and an inner circumference of the hole of the core. A motor according to any one of the preceding claims. 7. The motor according to claim 1, wherein a gap between the rotating shaft and the core is filled with an adhesive having elasticity after hardening.