JP2003032956A - Motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor which can be constructed, so as to eliminate the adjustment of the loosening in the thrust direction, stabilize its bearing and avoid thrust noise. SOLUTION: This motor has a motor case 1, a stator and a rotor rotating relative to the rotor which are housed in the motor case 1, a motor shaft 4 integrated with the rotor, and a bearing 5 supporting the motor shaft 4 rotatably at a cylindrical bearing holder 6 of the motor case 1. Pressure is applied radially to the bearing 5 via its outer surface to fix the bearing 5 to the bearing holder 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for controlling play in a thrust direction between a bearing mounted on a motor shaft and a bearing holding portion of a motor case in a motor.

[0002]

2. Description of the Related Art A motor is constructed, for example, as shown in FIG. The stator assembly 2 is mounted along the inner circumference of the motor case 1, and the rotor assembly 3 is rotatably arranged on the inner circumference side of the stator assembly 2 and is integrally mounted on the rotor assembly 3. Motor shaft 4 is motor case 1
Is inserted into the motor case 1 so as to pass through the center of the.
The bearing 5 that supports the motor shaft 4 is, for example, a ball bearing, and is fitted and mounted in front of both ends of the motor shaft 4. The bearing 5 is housed and held in a bottomed cylindrical bearing holder 6 provided at both ends of the motor case 1. A step portion 7 is provided between both ends of the motor shaft 4, and a stop ring 8 is attached to the step portion 7, and the end surface of the inner race 5 a of the bearing 5 is in contact with the stop ring 8. A washer 9 is interposed between the end surface 6a of the bearing holding portion 6 and the end surface of the outer race 5b of the bearing 5 in order to regulate play in the thrust direction. Worms 10 and 11 are attached to both ends of the motor shaft 4 outside the motor case 1.
A mounting frame 12 for mounting the motor on the device is arranged along both ends of the motor case 1, and is mounted with bolts 13 and nuts 14. The bolt 13 is attached to the motor case 1 and the stator assembly 2 from the one mounting frame 12.
Through the other mounting frame 12 through the bolt 1
A nut 14 is screwed onto the tip of the screw 3.

In the motor having such a structure, play is provided so that the motor shaft 4 can be somewhat slid in the thrust direction. However, if the play in the thrust direction is large, thrust noise and vibration are increased, which is a quality problem. If a problem occurs and there is no backlash in the thrust direction when tightened from the thrust direction, the mechanical loss increases, which affects the motor characteristics. The cause of this backlash in the thrust direction is considered to be the variation in size of each component and the variation in combination such as stacking of iron cores.

When the backlash in the thrust direction of this motor is regulated, a plurality of washers 9 are inserted between the end surface 6a of the bearing holding portion 6 and the outer race 5b of the bearing 5 as shown in FIG. is doing. At this time, 3 to 4 types of washers 9 having different thicknesses are provided so that there is a certain amount of backlash in the thrust direction.
For example, washers 9a, 9b, 9c, 9d having different thicknesses are prepared to cope with variations in dimensions in the thrust direction. In this case, it is necessary to reconfirm the play in the thrust direction after assembly, and there may be no play in the thrust direction, which requires adjustment time.

Further, as shown in FIG. 8, the outer periphery of the outer race 5b of the bearing 5 and the inner surface of the bearing holding portion 6 may be adhered with an adhesive 30 to fix the bearing 5 so that it does not move in the thrust direction. . In the case of the example of FIG. 8, a washer 9 and a wave washer 15 are interposed between the outer race 5b of the bearing 5 and the end surface 6a of the bearing holding portion 6. In the case of bonding with the adhesive agent 30 as described above, it is extremely important and difficult to maintain the quality of the adhesive agent 30, such as management of the coating amount of the adhesive agent 30, management of the state of the bonding surface, and drying conditions. Further, there is a problem in ensuring reliability such as occurrence of trouble due to flow of adhesive.

[0006]

In the former method of controlling the backlash in the thrust direction of the above-mentioned conventional example, it is difficult to assemble and adjust, and it takes a long processing time, which causes a cost increase. Further, when the bearing is fixed by adhesion, there is a problem that quality control is difficult and reliability is insufficient.

The present invention has been made in view of the above-mentioned points, and it is an object of the present invention to provide a motor capable of fixing a bearing without adjusting the play in the thrust direction and having a structure that does not generate thrust noise. And

[0008]

In order to solve the above-mentioned problems, a motor according to claim 1 of the present invention comprises a stator and a rotor which rotates relative to the stator inside a motor case, and rotates a motor shaft integral with the rotor. In a motor in which a bearing that is freely supported is held in a cylindrical bearing holding portion of a motor case, the bearing is fixed to the bearing holding portion by applying pressure in the radial direction from the outer surface of the bearing. By fixing the bearing by applying pressure in the radial direction from the outer surface of the bearing, the bearing does not move in the thrust direction, thrust noise is eliminated, and the adhesive does not fix with the adhesive. Is eliminated and the adjustment of the backlash in the thrust direction is unnecessary, the effect of reducing the assembly processing cost is increased and the cost can be reduced.

A motor according to a second aspect of the present invention is the motor according to the first aspect, in which a mounting frame for mounting the motor on a device or the like is attached to a motor case and the mounting frame is extended to a bearing-corresponding portion on an outer periphery of a bearing holding portion. It is characterized in that the bearing holding portion is pressed from the outer periphery by the mounting frame. In this case, the bearing can be fixed by pressing the bearing holding portion from the outer periphery using the mounting frame without providing any special component.

According to a third aspect of the present invention, the motor according to the first aspect is characterized in that the bearing is fixed by pressing a ring material into the outer periphery of the cylindrical bearing holding portion of the motor case to press the ring material from the outer periphery. And By using the ring member which is a separate member, the bearing holding portion can be strongly pressed from the outer periphery and the bearing can be securely fixed.

According to a fourth aspect of the present invention, in the third aspect of the invention, the corner R for guiding the press-fitting of the ring member in at least one direction of the bearing holding portion of the motor case or the ring member or a chamfer or a slope is provided. Is characterized by. In this case, the ring material can be smoothly press-fitted.

According to a fifth aspect of the present invention, a motor and a rotor that rotates with respect to the stator are provided inside the motor case, and a bearing that rotatably supports a motor shaft integral with the rotor is cylindrical in the motor case. In the motor held by the bearing holder, the bearing holder is deformed to position and fix the bearing. By deforming the bearing holder and positioning and fixing the bearing, there is no movement in the thrust direction of the bearing, there is no thrust noise, and there is no trouble due to the outflow of adhesive because it is not fixed with adhesive. Also, since there is no need to adjust the backlash in the thrust direction, the effect of reducing the assembly processing cost is increased and the cost can be reduced.

According to a sixth aspect of the present invention, in a motor case, a stator and a rotor that rotates with respect to the stator are provided in the motor case, and a bearing that rotatably supports a motor shaft integral with the rotor is cylindrical in the motor case. In the motor held by the bearing holding portion, the bearing holding portion is provided with an abutting member, and the abutting member is abutted and fixed to the bearing. Since the bearing holder is provided with the abutting member and the abutting member is abutted and fixed to the bearing, the bearing does not move in the thrust direction, the thrust noise is not generated, and the adhesive is not used for fixing. The trouble due to the outflow of the adhesive is eliminated, and the adjustment of the play in the thrust direction becomes unnecessary, so that the effect of reducing the assembly processing cost becomes large and the cost can be reduced.

The invention of claim 7 of the present invention is the invention of claim 6
In the above, the abutting member has a rod shape.

The invention of claim 8 of the present invention is the invention of claim 7.
In the above, the bearing holding portion of the motor case is provided with a female screw hole, the pin-shaped abutting member is provided with a male screw portion, and the male screw portion of the abutting member is screwed into the female screw hole. The abutting member can be rotationally operated to abut against the bearing, and the abutting condition can be adjusted.

The invention of claim 9 of the present invention is the invention of claim 7.
In the above, a plurality of abutting members are arranged at equal intervals in the circumferential direction around the motor shaft. The butting member can be evenly butted against the bearing to stably fix the bearing.

A tenth aspect of the present invention is characterized in that, in the sixth aspect, a flat washer having a flat end face on the end face is interposed between the bearing and the abutting member. By interposing a flat washer, the bearing can be pressed uniformly by the abutting member and stably fixed.

According to an eleventh aspect of the present invention, a stator and a rotor that rotates with respect to the stator are provided in the motor case, and a bearing that rotatably supports a motor shaft integral with the rotor is cylindrical in the motor case. In the motor held by the bearing holder, the receiving member having a flat end surface is attached from the outside of the bearing holder so that the flat end surface abuts the bearing, and the receiving member is fixed at the end of the bearing holder. It is characterized by being formed. By mounting the receiving member with a flat end surface from the outside of the bearing holder so that the flat end surface abuts the bearing and fixing the receiving member at the end of the bearing holder, the bearing does not move in the thrust direction. , Thrust noise is not generated, and since adhesive is not used for fixing, trouble due to the outflow of adhesive is eliminated, and the adjustment of thrust backlash is not required, which greatly reduces the assembly processing cost. Therefore, the cost can be reduced.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Since the structure of the whole motor of the example of this embodiment is the same as that described in the conventional example, only the structure of the bearing portion different from the conventional one will be mainly described.

First, an example of the embodiment shown in FIG. 1 will be described.
The bearing holding portion 6 of the motor case 1 is formed in a cylindrical shape with a bottom, an insertion hole 16 is bored in the end surface portion 6a of the bearing holding portion 6, and the motor shaft 4 is inserted therein. Motor shaft 4
A step portion 7 is provided on the step portion 7, and a retaining ring 8 is attached to the step portion 7. The bearing 5 is a ball bearing and includes an inner race 5a, an outer race 5b, a plurality of balls 5c, and a ball retainer 5d. This bearing 5 is the motor shaft 4
The inner race 5a of the bearing 5 is in contact with the retaining ring 8 at one end thereof. The bearing 5 is housed in the bearing holding portion 6, and the outer surface of the outer race 5b of the bearing 5 is brought into close contact with the inner surface of the bearing holding portion 6.

In the case of the example of the present embodiment, the bearing holding portion 6 is pressed against the bearing 5 so that pressure is applied in the radial direction to the outer surface of the outer race 5b of the bearing 5.
Is fixed, and the bearing 5 is fixed to prevent the motor shaft 4 from moving in the thrust direction. When the bearing holder 6 is pressed against the bearing 5, in this example, the mounting frame 12 is used. The mounting frame 12 is integrally provided with a press-fitting cylinder portion 17 which is burred so as to extend from the mounting frame 12. The mounting frame 12 is attached to the motor case 1
When it is attached to the, the press-fitting cylinder portion 17 is press-fitted so as to be fitted on the outer periphery of the bearing holding portion 6. At this time, the bearing holder 6
Where D is the outer diameter of D and d is the inner diameter of the press-fitting cylinder portion D
The relationship is> d, and the bearing holder 6 is tightened by pressing the press-fitting cylinder portion 17 to press the bearing holder 6 against the bearing 5, and the bearing 5 can be fixed. In addition,
The motor case 1 and the mounting frame 12 generally use a ferrous metal material, but may be a synthetic resin molding material.

Next, an example of the embodiment shown in FIG. 2 will be described. This example is also basically the same as the above example, and the bearing holding portion 6 is pressed against the bearing 5 so that pressure is applied in the radial direction to the outer surface of the outer race 5b of the bearing 5, and the bearing 5 is fixed to the bearing holding portion 6. By fixing the bearing 5, the movement of the motor shaft 4 in the thrust direction is eliminated. Bearing holder 6
When pressing the bearing 5 against the bearing 5, in the case of this example, the mounting frame 12
A ring member 18 which is a separate component is used instead of. Then, the ring material 18 is press-fitted so as to be fitted on the outer periphery of the bearing holding portion 6. At this time, the outer diameter of the bearing holder 6 is D,
There is a relationship of D> d when the inner diameter of the ring member 18 is d, and the bearing member 6 can be fixed by pressing the link member 18 to tighten the bearing holding unit 6 and press the bearing holding unit 6 against the bearing 5. It is like this.

Further, in this example, the bearing holding portion 6 and the ring material 1
Corner R19 or chamfer or bevel in at least one direction of 8. In the case of this example, a corner R19 is provided in the ring material 18 and the bearing holding portion 6. With this configuration, when the ring member 18 is press-fitted into the bearing holder 6, the press-fitting installation becomes smooth.

Next, an example of the embodiment shown in FIG. 3 will be described. In the case of this example, the bearing holding portion 6 is formed in a cylindrical shape and has no end surface portion 6a. Then, the bearing 5 is fixed by deforming the end edge of the bearing holder 6 to regulate the position of the bearing 5. That is, as shown in FIG. 3, the bearing 5 is regulated and fixed by crushing the end edge of the bearing holding portion 6 as shown by the arrow to form the crimped portion 31. In the illustrated example, the caulking portions 31 are provided at equal intervals at four locations in the circumferential direction to fix the caulking portions 31. In addition, in this example, the bearing holding portion 6 is formed into a cylindrical shape and the end surface is opened so as to be easily deformed (caulked) only by the plate thickness. However, as in the above example, the bearing holding portion 6 has the end surface portion 6a.
Even if it has a bottomed tubular shape, it can be similarly fixed.

Next, an example of the embodiment shown in FIG. 4 will be described. In this example, the bearing 5 is fixed by abutting the abutting member 20 from the outside on the end face of the bearing 5 in the thrust direction, so that the motor shaft 4 does not move in the thrust direction. In the case of this example, the abutting member 20 has a rod shape and is attached to the end surface portion 6 a of the bearing holding portion 6. When the rod-shaped abutting member 20 is attached to the end surface portion 6a, the male screw portion 21 is provided on the outer periphery of the abutting member 20 and the female screw hole 22 is provided in the end surface portion 6a. Is screwed into the female screw hole 22. By doing so, the abutting member 20 can be easily abutted against the bearing 5 to fix the bearing 5, and the degree to which the abutting member 20 is abutted can be adjusted. A plurality of the abutting members 20 are mounted on the end surface portion 6a, but the motor shaft 4
When arranging a plurality in the circumferential direction with respect to the center, they are arranged at equal intervals. By doing so, the abutment member 20 can be evenly abutted against the bearing 5, and the fixing of the bearing 5 can be stabilized.

In the case of this example, the flat washer 23 having a flat end face on the end face against which the abutting member 20 is abutted is abutted on the abutting member 20.
And the bearing 5 are interposed. The flat washer 23 incorporated in the bearing holder 6 is abutted against the end face portion 6a of the bearing member 2
0 is attached by screwing the male screw portion 21 into the female screw hole 22, and the butting member 20 is tightened. When the butting member 20 comes into contact with the flat washer 23, the butting member 20 is completely tightened. By thus interposing the plain washers 23, the abutment of the abutment member 20 can be made more uniform, and the bearing 5 can be stably fixed. After the abutting member 20 is fastened and fixed, an adhesive may be applied to prevent loosening of the screw engagement between the male screw portion 21 and the female screw hole 22.

Next, an example of the embodiment shown in FIG. 5 will be described. In the case of this example, the bearing member 24 having a flat end face is attached from the outside of the bearing holding portion 6, and the bearing member 5 is fixed by caulking and fixing the receiving member 24 at the end portion of the bearing holding portion 6. In the case of this example, the bearing holding portion 6 is formed in a cylindrical shape without the end surface portion 6a and the end portion is opened, and a space for installing the receiving member 24 and a space for caulking the bearing holding portion 6 are secured. The receiving member 24 is formed in a disk shape that closes the opening at the end of the bearing holding portion 6, and has projections 25 protruding at equal intervals at a plurality of locations (four locations in this example) in the circumferential direction. The concave portion 2 into which the convex portion 25 is fitted at the end of the bearing holding portion 6
6 is provided, the opening at the end of the bearing holding portion 6 is closed by the member 24, the convex portion 25 is fitted in the concave portion 26, and both sides of the concave portion 26 are deformed to form the concave portion 27. The convex portion 25 is fixed to the concave portion 26. As a result, the receiving member 24 is fixed, and the bearing 5 is fixed by the receiving member 24.

[0028]

Since the present invention is constructed as described above, the bearing can be fixed to the bearing holding portion of the motor case so as to stop the movement of the bearing in the thrust direction, and the generation of thrust noise can be prevented. Moreover, unlike the conventional method, the bearing is not fixed with an adhesive, so there is no trouble due to the outflow of the adhesive, and there is no need to adjust the play in the thrust direction, reducing assembly costs. The effect is great and the cost can be reduced.

[Brief description of drawings]

FIG. 1 shows a main part of an example of an embodiment of the present invention,
(A) is sectional drawing, (b) is an exploded sectional view of (a).

FIG. 2 shows a main part of another example of the above, (a) is a sectional view,
(B) is an exploded sectional view.

FIG. 3 shows a main part of another example of the above, (a) is a sectional view,
(B) is a side view.

FIG. 4 shows a main part of another example of the above, (a) is a sectional view,
(B) is a side view.

FIG. 5 shows a main part of another example of the above, (a) is a sectional view,
(B) is a side view and (c) is a view in the direction of arrow A in (b).

FIG. 6 shows the entire motor, (a) is a cross-sectional view taken along the line AA of (b), and (b) is a side view.

FIG. 7 is a sectional view showing a conventional example.

FIG. 8 is a cross-sectional view showing another conventional example.

[Explanation of symbols]

1 motor case 4 motor shaft 5 bearings 6 Bearing holder 6a End face part 12 mounting frame 18 Ring material 20 Abutment member 21 Male thread 22 Female screw hole 23 Plain washer 24 Abutting member

Claims (11)

[Claims] 1. A motor in which a stator and a rotor that rotates relative to the stator are provided inside a motor case, and a bearing that rotatably supports a motor shaft integral with the rotor is held in a cylindrical bearing holding portion of the motor case. The motor is characterized in that the bearing is fixed to the bearing holder by applying pressure in the radial direction from the outer surface of the bearing. 2. A mounting frame for mounting a motor to a device or the like is attached to a motor case, and the mounting frame is extended to a bearing-corresponding portion on the outer periphery of the bearing holding part to hold the bearing holding part from the outer periphery by the mounting frame. The motor according to claim 1, wherein the motor is attached. 3. The motor according to claim 1, wherein the bearing is fixed by pressing a ring material into the outer periphery of the cylindrical bearing holding portion of the motor case to press it from the outer periphery. 4. The motor according to claim 3, wherein a corner R for guiding the press-fitting of the ring material or a chamfer or a slope is provided in at least one direction of the bearing holding portion of the motor case or the ring material. 5. A motor in which a stator and a rotor rotating with respect to the stator are provided inside a motor case, and a bearing for rotatably supporting a motor shaft integral with the rotor is held in a cylindrical bearing holding portion of the motor case. A motor characterized in that the bearing holding portion is deformed to position and fix the bearing. 6. A motor in which a stator and a rotor rotating with respect to the stator are provided inside a motor case, and a bearing for rotatably supporting a motor shaft integral with the rotor is held in a cylindrical bearing holding portion of the motor case. A motor comprising a bearing holding portion provided with an abutting member and the abutting member abutting against a bearing to be fixed. 7. The motor according to claim 6, wherein the abutting member has a rod shape. 8. The bearing holding portion of the motor case is provided with a female screw hole, the pin-shaped abutting member is provided with a male screw portion, and the male screw portion of the abutting member is screwed into the female screw hole. Motor described. 9. The motor according to claim 7, wherein a plurality of abutting members are arranged at equal intervals in the circumferential direction around the motor shaft. 10. The motor according to claim 6, wherein a flat washer having a flat end surface is provided between the bearing and the abutment member. 11. A motor in which a stator and a rotor rotating with respect to the stator are provided inside a motor case, and a bearing for rotatably supporting a motor shaft integral with the rotor is held in a cylindrical bearing holding portion of the motor case. A motor comprising: a receiving member having a flat end surface attached from the outside of the bearing holding portion so that the flat end surface abuts the bearing, and the receiving member is fixed at the end portion of the bearing holding portion.