JP4639738B2 - motor - Google Patents

Description

  The present invention relates to a bearing fixing structure of a motor, and more particularly to a bearing preload structure.

The motor to which the present invention is directed includes a stator in which a coil is wound, a load-side housing and an anti-load-side housing that are fitted and fixed to both ends of the stator, and openings provided in the load-side housing and the anti-load-side housing, respectively. Each of the load side bearing and the anti-load side bearing inserted into the rotor, and a rotor supported rotatably between the load side bearing and the anti-load side bearing, and an adhesive is provided between the housing opening and the outer periphery of the bearing. What is inserted and fixed is known (for example, refer to Patent Document 1 and Patent Document 2).
JP-A-9-14275 JP 62-190123 A

  Furthermore, when the adhesive is inserted between the housing opening and the outer periphery of the bearing and fixed, the fixing with the adhesive is performed in a state where a fixed preload is applied to hold the bearing inserted in the opening of the housing against the center of the motor. Is doing. When “fixed position preload” is adopted as a method of applying preload to the bearing that supports the rotor, the following methods 1 to 3 are conventionally known.

Method 1: A method of setting a dimensional difference in the axial direction by controlling the dimensional accuracy between the stator and the rotor, and applying a preload by assembling.
FIG. 5 shows a fixed position preload method according to method 1. In the figure, 2 is a housing, 3 is a bearing, 5 is a motor shaft, 6 is a magnet, 7 is a stator, 8 is a housing, 9 is a bearing cover, and 10 is a fixing screw. is there.
In this motor, the inner ring of the bearing 3 is fixed to the motor shaft 5 having the magnet 6, the outer ring of the bearing 3 is fixed to the opening of the anti-load side housing 2, and the bearing 3 on the load side housing 8 side is The cover 9 is fixed to the load-side housing 8 by being fixed to the load-side housing 8 with fixing screws 10.
Then, the dimensions of the parts of the anti-load side housing 2, the bearing 3, the motor shaft 5, and the stator 7 are accurately manufactured and the parts are assembled in this manner, so that the extending portion 2a of the anti-load side housing 2 is By fixing the bearing 3 to the stepped portion 5a of the motor shaft 5 in a pressed state, the preload application state is maintained (without using a spring).

Method 2: A method of injecting an adhesive from an inlet or the like in a state where a preload is applied by a spring such as a circular wave washer, and fixing the bearing.
6 is a fixed position preload method according to method 2. In the figure, 2 is a housing, 3 is a bearing, 4 is an adhesive, 5 is a motor shaft, 6 is a magnet, 7 is a stator, 8 is a housing, 9 is a bearing cover, Reference numeral 10 denotes a fixing screw, 11 denotes a preload spring using a wave washer, and 12 denotes an adhesive injection port.
FIG. 7 is a view showing a specific shape of the wave washer 11, wherein (a) is a front view and (b) is a side view. In (a) and (b), the convex (mountain) portion is indicated by ◯, the node (intermediate) portion is indicated by ×, and the concave (valley) portion is indicated by ●. The wave washer 11 is a washer in which an annular thin plate is corrugated as shown in the drawing and the spring characteristic against compression is taken into consideration.
This motor is formed by fixing an inner ring of a bearing 3 to a motor shaft 5 provided with a magnet 6 and fixing an outer ring of the bearing 3 to an opening of the anti-load side housing 2. By interposing the wave washer 11 of FIG. 7 between the portion 2 a and the bearing 3, the wave washer 11 fixes the bearing 3 to the stepped portion 5 a of the motor shaft 5 in a pressed state and applies a preload. In this state, when the adhesive 4 is injected from the adhesive injection port 12, the adhesive 4 passes through the adhesive passage 12 a opened in the anti-load side housing 2, and between the anti-load side housing 2 and the bearing 3. The gap is entered and the two are firmly coupled, and the preload application state is maintained.

Method 3: A method in which an adhesive is injected and a bearing is bonded and fixed in a state where a preload is applied with a weight.
FIG. 8 shows a fixed position preloading method according to method 3, in which 2 is a housing, 3 is a bearing, 4 is an adhesive, 5 is a motor shaft, 6 is a magnet, 7 is a stator, 8 is a housing, 9 is a bearing cover, 10 is a fixing screw, and 13 is a weight.
This motor is formed by fixing an inner ring of a bearing 3 to a motor shaft 5 having a magnet 6 and fixing an outer ring of the bearing 3 to an opening of the anti-load side housing 2. The motor is kept upright with the load side housing 8 as the ground, and the bearing 3 is pressed against the stepped portion 5a of the motor shaft 5 by the weight 13 to apply the preload, and the adhesive 4 is applied in this state. It inject | pours into the clearance gap between the anti-load side housing 2 and the bearing 3, and couple | bonds both firmly. After the adhesive 4 is hardened and the coupling between the two is completed, the preload application state is maintained by removing the weight 13.

However, each of the conventional techniques has the following problems.
According to the method 1, it is necessary to manage the dimensional tolerances of the component parts with high accuracy, resulting in an increase in cost.
According to Method 2, since the wave washer 11 covers the gap between the housing opening and the bearing, it becomes a structural obstacle to the injection of the adhesive 4, and it is difficult to inject the adhesive 4. It is also difficult to check the situation.
According to the method 3, since the weight 13 cannot be removed until the adhesive 4 is cured, the tact time is increased.

To solve the above problems, a first aspect of the present invention relates to a motor, a stator having a coil, and c Woojin grayed respectively provided at both ends of the stator, respectively provided on the front KIHA Woojin grayed a bearing that is inserted into the first opening, a motor constituted by a rotor which is supported rotatably between each previous SL bearings, anti stator side of one of the bearings of each said bearing And at least a bearing cover that is attached to the housing provided with the one bearing and provided with a second opening in the center, the diameter of the one bearing and the one bearing A gap for injecting adhesive is formed between the housing provided on the outer side in the direction, the inner ring of the one bearing is fixed to the rotor, and a part of the outer periphery of the second opening is The gap Since the outer ring of the one bearing is pressed against the other bearing side by the bearing cover, the other part of the outer periphery of the second opening is provided on the outer peripheral side of the gap. I am trying to do it.
According to a second aspect of the invention, in the motor according to claim 1, wherein the bearing cover is formed like a bridge as viewed from the side of and substantially "mouth" shape in a plan view, facing the four sides of the second opening One opposite side is provided on the inner peripheral side with respect to the gap, and the other one opposite side of the second opening is provided on the outer peripheral side with respect to the gap.

  According to the first and second aspects of the present invention, since the spring serves as the bearing cover, there is no structural obstacle to injecting the adhesive, and the adhesive injecting operation can be facilitated. In addition, it is possible to avoid high-precision management of the dimensional tolerances of the component parts. Further, a long tact time can be avoided.

<First embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a view showing a bearing preload structure motor according to a first embodiment, in which (a) is a front view and (b) is a side view. FIGS. 2A and 2B are views for explaining a bearing cover and preload spring used in the first embodiment. FIG. 2A is a front view, and FIG. 2B is a side view.
In FIG. 1, reference numeral 1 denotes a preload spring that also serves as a bearing cover according to the present invention. The other reference numerals are the same as those of the conventional example, 2 is the anti-load side housing, 3 is the bearing, 4 is the adhesive, 5 is the motor shaft, 6 is the magnet, 7 is the stator, 8 is the load side housing, and 9 is the bearing. The cover 10 is a fixing screw.
In FIG. 2, the bearing cover / spring material 1 is obtained by punching a spring material into a generally “mouth” shape having an opening 1a at the center in a plan view (plan view) of FIG. A fixing screw hole 1c is provided on the other two sides 1d and 1d, and the central part is formed in a convex shape (bridge shape) 1e in the side view (side view) of (b).
The motor shaft 5 shown in FIG. 1 is passed through the mouth-shaped central opening 1a of the bearing cover / spring material 1, and a part of the opening of the anti-load side housing 2 is covered with the motor shaft 5 shown in FIG. It is fixed to the non-load-side housing 2 with a fixing screw 10 in the direction in which the fixed position preload is applied. Thereafter, the adhesive 4 is injected into the gap between the anti-load side housing 2 and the anti-load side bearing 3 using the wide center opening 1a of the mouth of the bearing cover / preload spring 1 so that the preload application state is maintained. Become so.
Thus, according to the first embodiment, by using the bearing cover and preload spring 1 having a mouth-shaped central opening, the injection of the adhesive can be facilitated. Further, since the fixing is performed by using the spring and the adhesive together, high-precision management of the dimensional tolerances of the component parts can be avoided, and further, a long tact time can be avoided because no weight is used for bonding the bearing.

<Second embodiment>
Next, a second embodiment will be described with reference to FIGS.
FIGS. 3A and 3B are views showing a bearing preload structure motor according to the second embodiment, wherein FIG. 3A is a front view and FIG. 3B is a side view. 4A and 4B are views for explaining a preload spring used in the second embodiment, where FIG. 4A is a front view and FIG. 4B is a side view.
In FIG. 3, 1 ′ is a preload spring according to the present invention. The other reference numerals are the same as those of the conventional example, 2 is the anti-load side housing, 3 is the bearing, 4 is the adhesive, 5 is the motor shaft, 6 is the magnet, 7 is the stator, 8 is the load side housing, and 9 is the bearing. A cover 10 is a fixing screw, and 15 is a large hole formed in a bearing facing portion of the anti-load side housing 2. A part of the anti-load side housing 2 extends from the anti-load side housing 2 on its opening to form a housing extension 2a.
In FIG. 4, the spring material 1 includes an annular portion 1 a ′ at the center and a spring extending portion 1 b extending from the annular portion 1 a ′ toward the outside in the diameter direction in the plan view of FIG. In the side view (side view) of (b), the central part is formed in a convex shape (bridge shape) 1c '.
Therefore, the motor shaft 5 of FIG. 1 is passed through the opening 1d ′ of the annular portion 1a ′ of the spring material 1 ′, and the spring extending portion 1b ′ is interposed between the housing extending portion 2a and the bearing 3. The fixed position preload is applied to the anti-load side bearing 3 by the spring pressure. In this state, the adhesive 4 is directly injected from the large hole 15 of the anti-load side housing 2 into the gap between the anti-load side housing 2 and the anti-load side bearing 3 that can be seen beside the preload spring 1 ′. Will be maintained.
As described above, according to the second embodiment, it is possible to easily inject the adhesive by using the bridge-shaped preload spring 1 ′ having an opening at the center and the anti-load side housing 2 having the hole 15. can do. Further, since the fixing is performed by using the spring and the adhesive together, high-precision management of the dimensional tolerances of the component parts can be avoided, and further, a long tact time can be avoided because no weight is used for bonding the bearing.

As described above, according to the first embodiment, it is possible to facilitate the injection of the adhesive in the “fixed position preload structure” in which the adhesive is injected after the preload is applied by the spring and the bearing is fixed. it can. In addition, since the spring and the adhesive are used together, it is possible to avoid high-precision management of the dimensional tolerance of the component parts. Furthermore, since no weight is used for bearing adhesion, a long tact time can be avoided.
Further, according to the second embodiment, it is possible to facilitate the injection of the adhesive in the “fixed position preload structure” in which the adhesive is injected after the preload is applied by the spring and the bearing is fixed. In addition, since the spring and the adhesive are used together, it is possible to avoid high-precision management of the dimensional tolerance of the component parts. Furthermore, since no weight is used for bearing adhesion, a long tact time can be avoided.

It is a figure which shows the bearing preload structure motor which concerns on a 1st Example, (a) is a front view, (b) is a side view. It is a figure explaining the bearing cover and preload spring used for the 1st example. It is a figure which shows the bearing preload structure motor which concerns on a 2nd Example, (a) is a front view, (b) is a side view. It is a figure explaining the bridge shape preload spring used for the 2nd example. It is a figure explaining the fixed position preload method by the conventional method 1. FIG. It is a figure explaining the fixed position preload method by the conventional method 2. FIG. It is a figure explaining the wave washer used for the conventional method 2. FIG. It is a figure explaining the fixed position preload method by the conventional method 3. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bearing cover and preload spring 1a Opening part 1b Opposite 2 sides 1c Screw hole 1d Other 2 opposing sides 1e Center convex-shaped (bridge shape) part 1 'Bridge shape preload spring 1a' Annular part 1b 'Extension part 1c' Center convex shape (bridge shape) 1d 'opening 2 Housing 2a Extension 3 Bearing 4 Adhesive 5 Rotor shaft 6 Magnet 7 Stator 8 Load side housing 9 Bearing cover 10 Fixing screw 11 Preload spring 12 Adhesive inlet 13 Weight 15 Large hole in housing

Claims (2)

A stator having a coil, and c Woojin grayed respectively provided at both ends of the stator, a bearing that is inserted into the first opening portion provided to each front KIHA Woojin grayed, between each pre SL bearing A motor composed of a rotor that is rotatably supported,
At least a bearing cover that is attached to the housing provided with the one bearing so as to be disposed on the side opposite to the stator of any one of the bearings and that has a second opening at the center. Have
A gap for injecting an adhesive is formed between the one bearing and the housing provided on the radially outer side of the one bearing,
An inner ring of the one bearing is fixed to the rotor;
By providing a part of the outer periphery of the second opening on the inner peripheral side with respect to the gap, the outer ring of the one bearing is pressed to the other bearing side by the bearing cover,
The other part of the outer periphery of the second opening is a motor provided on the outer peripheral side of the gap . The bearing cover is formed in a substantially “mouth” shape in plan view and in a bridge shape in side view ,
One opposing side of the four sides of the second opening is provided on the inner peripheral side with respect to the gap ,
The motor according to claim 1 , wherein the other opposite side of the second opening is provided on the outer peripheral side of the gap .

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