JP2010242855A - Fixing method and fixing structure of rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing method and fixing structure of a rolling bearing reducing the number of parts, allowing the roller bearing to be fixed by crimping a housing after assembling the roller bearing. <P>SOLUTION: In the method for fixing a bearing that supports a motor rotating shaft and the like in a bearing housing, the bearing 2 is inserted into a recessed portion 1a of the bearing housing 1. The opening end portion of the recessed portion 1a of the bearing housing 1 is crimped radially inward along the peripheral edge portion of the bearing 2 by a crimping processing. The end surface of an outer ring 2a of the bearing 2 is latched by a deformation-processed portion 1e of the bearing housing 1. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rolling bearing that supports a rotating shaft of a rotating electrical machine, or a rolling bearing that supports a ball screw of an electric actuator in a bearing housing and a fixing structure.

  In a rotating electrical machine such as a small electric motor or an electric actuator using a ball screw, a rolling ball bearing is used as a bearing that supports the rotating shaft or the ball screw.

Conventionally, fixing methods A to D as shown in FIG. 7 are employed as a method of fixing the rolling ball bearing.
The fixing method shown in FIG. 7A is a fixing method using a snap ring, where 100 is a bearing housing, 101 is a rolling ball bearing, and 102 is a rotating shaft. The rolling ball bearing 101 is disposed in the recess 103 of the bearing housing 100 and supports the rotating shaft 102 in a freely rotatable manner. The rolling ball bearing 101 is fixed to an axially attached end surface of the outer ring 101 a in contact with the axial inner wall surface 103 a of the recess 103 of the bearing housing 100, and the axial end surface of the inner ring 101 b is attached to the rotary shaft 102. Locked by the snap ring 104. Further, the rolling ball bearing 101 is fixed to the outer side axial end surface of the outer ring 101a via a hole snap ring 105 attached to the inner wall surface of the recess 103.

  The fixing method shown in FIG. 7B is a fixing method using a retainer plate, in which 200 is a bearing housing, 201 is a rolling ball bearing, and 202 is a rotating shaft. The rolling ball bearing 201 is disposed in the recess 203 of the bearing housing 200 and supports the rotating shaft 202 in a freely rotatable manner. The rolling ball bearing 201 is fixed to an axially attached end surface of the outer ring 201 a in contact with the axial inner wall surface 203 a of the recess 203 of the bearing housing 200, and the axial end surface of the inner ring 201 b is attached to the rotary shaft 202. Locked by the snap ring 204. In the rolling ball bearing 201, the outer axial end surface of the outer ring 201a is fixed to the end surface 203 of the bearing housing 200 via a retainer plate 206 attached by a retainer fixing screw 205.

  The fixing method shown in FIG. 7C is a fixing method using a hole snap ring, wherein 300 is a bearing housing, 301 is a rolling ball bearing, and 302 is a rotating shaft. The rolling ball bearing 301 is disposed in the recess 303 of the bearing housing 300 and supports the rotating shaft 302 in a rotatable manner. The rolling ball bearing 301 is fixed to an axially attached end surface of the outer ring 301 a in contact with the axial inner wall surface 303 a of the recess 303 of the bearing housing 300, and the axial end face of the inner ring 301 b is mounted on the rotary shaft 302. It is locked by a snap ring 304. Further, in the rolling ball bearing 301, the outer axial end face of the outer ring 301a is held by a hole snap ring (SI type) 305 disposed in the recess 303 of the bearing housing 300.

The fixing method shown in FIG. 7D is a fixing method using insert ring casting + adhesive, 400 is a bearing housing, 401 is a rolling ball bearing, and 402 is a rotating shaft. The rolling ball bearing 401 is disposed in the recess 403 of the bearing housing 400 and supports the rotating shaft 402 in a freely rotatable manner. The rolling ball bearing 401 is fixed with the inner axial end surface of the outer ring 401 a in contact with the axial inner wall surface 403 a of the recess 403 of the bearing housing 400, and the outer axial end surface of the inner ring 401 b is fixed to the stepped portion 402 a of the rotating shaft 402. It is locked to. In this rolling ball bearing 401, an insert ring 404 is fixed between the peripheral surface of the outer ring 401a and the inner wall surface of the recess 403 of the bearing housing 400 by die casting and using an adhesive.
Table 1 summarizes the conventional fixing methods.

  As is apparent from Table 1, according to the conventional bearing fixing method, in the fixing method (A) using the snap ring, a gap is generated in the axial direction, and play is possible in the axial direction. It is a problem. Further, the fixing method (B) is problematic in terms of space saving and cost. Further, the fixing method (C) is a problem in terms of creep countermeasures, and the fixing method (D) is a problem in terms of assemblability, management of adhesive strength, and cost.

Patent Document 1 discloses a method using an adhesive.
By the way, a method of using caulking for fixing parts is known (see Patent Document 2). In this method, as shown in FIG. 8, the housing 500 and the front cover 501 are fixed by caulking. In this method, one surface of the front cover 501 is pressed against the flange 502 provided on the outer periphery of the housing 500, the end surface of the mounting portion 503 is crimped, and the front cover 501 is fixed to the housing 500 with the deformed portion 503a and the flange 502. Yes. At this time, in order to prevent deformation of the housing 500 toward the inner diameter side, a recess 503b is formed on the end surface to prevent deformation toward the inner diameter side.

Japanese Utility Model Publication No. 63-193120 JP 2007-288939 A

  However, in order to fix the front cover 501 to the housing 500 with the deformed portion 503a and the flange 502 by crimping the end surface of the mounting portion 503 to fix the housing 500, a concave portion is formed on the end surface to prevent deformation of the housing 500 toward the inner diameter side. It is necessary to form 503b. Since a bearing is mounted on the inner diameter side of the housing 500, if a protrusion is formed on the inner diameter side, a problem that the bearing cannot be assembled occurs.

  The present invention solves the above problems and provides a rolling bearing fixing method and a fixing structure capable of fixing the rolling bearing and reducing the number of parts by caulking the housing after assembling the rolling bearing. For the purpose.

In order to solve the above problems, the present invention provides a method of fixing a bearing supporting a rotating shaft of an electric motor or the like in a bearing housing. The outer ring end surface of the bearing is locked by the plastic processing portion of the bearing housing by caulking the opening end of the bearing along the peripheral edge of the bearing to the inner diameter side by caulking, and in addition to applying shrinkage stress to the inner diameter of the housing. It is to have done.
Further, the present invention is that a bearing housing that holds the bearing is made of a material that can be plastically processed.
Furthermore, the present invention is to caulk the shoulder provided on the periphery of the concave portion of the bearing housing along the circumferential direction with a caulking punch having a sharp cross section.
Furthermore, the present invention is to form a plastic working portion by optimizing three elements of the housing depth, the caulking punch cross-sectional shape, and the caulking punch pressing amount for each material of the bearing housing.
Further, the present invention provides a structure in which a bearing supporting a rotating shaft of an electric motor or the like is fixed in a bearing housing, and the concave portion of the bearing housing is arranged along a peripheral edge portion of the bearing inserted in the concave portion provided in the bearing housing. The opening end portion of the bearing is caulked to the inner diameter side, and the outer ring end surface of the bearing is locked by the plastic working portion of the bearing housing.

According to the first aspect of the present invention, it is possible to provide an inexpensive method for fixing a bearing without generating backlash in the thrust direction for fixing the bearing and without using small parts or auxiliary materials.
According to the second aspect, since the bearing housing is made of a material that can be plastically processed, caulking can be easily performed.
According to the third aspect, since the caulking process is performed along the circumferential direction by the caulking punch, the bearing can be reliably held by the plastic processing portion.
According to the fourth aspect, the housing depth, caulking punch cross-sectional shape, and caulking punch pushing amount are set for each material and housing diameter of the bearing housing, so that the bearing can be reliably held by the optimal plastic working portion. .
According to the fifth aspect, the opening end of the recess of the bearing housing is caulked to the inner diameter side, and the outer ring end surface of the bearing is locked by the plastic processing portion of the bearing housing. The bearing can be fixed to

BRIEF DESCRIPTION OF THE DRAWINGS It is a fragmentary sectional view which shows the fixing method and fixing structure of a rolling bearing by embodiment of this invention, (A1) (B1) (C1) is sectional drawing which shows the bearing before crimping, (A2) (B2) (C2) Are sectional views showing the bearing after crimping, and (A3), (B3) and (C3) are sectional views showing the plastic working state after crimping. It is a conceptual sectional view showing a positional relation of a processing part to a bearing housing and a shape of a caulking punch. It is a conceptual diagram which shows the blade-tip shape of a caulking punch. FIG. 6 shows a caulking method, (a) is a conceptual diagram when caulking is performed at the same time on the circumference, (b) is a conceptual diagram when caulking is performed in four rotations symmetrically, and (c) is 3 in rotational symmetry. It is a conceptual diagram in the case of performing caulking to division. (A1) to (A3) are cross-sectional views showing plastic deformation when the amount of indentation d is reduced, and (B1) to (B3) adjust the amount of plastic deformation by sharpening the caulking punch tip angle θ dimension. It is sectional drawing. It is sectional drawing which shows the fixing method of the bearing by other embodiment of this invention. A conventional rolling ball bearing fixing method is shown, the fixing method shown in (A) is a sectional view showing a fixing method using a snap ring, and the fixing method shown in (B) is a sectional view showing a fixing method using a retainer plate. (C) is a sectional view showing a fixing method using a snap ring for holes, and the fixing method shown in (D) is a sectional view showing a fixing method using insert ring casting + adhesive. It is a fragmentary sectional view which shows the conventional fixing method which used the crimping process for fixation of components.

  By caulking the housing after assembling the rolling bearing, there is no play in the thrust direction when fixing the bearing, and the rolling bearing is locked and fixed by the plastic processing part of the bearing housing, reducing the number of parts. I planned.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 (A1) to (C3) are partial cross-sectional views for explaining a method of fixing a rolling bearing according to the present invention. FIG. 1 (A1) is a housing depth dimension of a bearing housing 1 such as a motor flange. L a indicates the status set to _{L 1,} FIG. 1 (B1) shows a state of setting the housing depth L to _{L 2,} FIG. 1 (C1) is set a housing depth L to _{L 3} Shows the state. Here, the relationship is L ₁ > L ₂ > L ₃ . 1 (A2), (B2), and (C2) are partial cross-sectional views showing a state after crimping from the states of FIGS. 1 (A1), (B1), and (C1). 1 (A3), (B3), and (C3) are partial enlarged views of FIGS. 1 (A2), (B2), and (B3).

  In FIG. 1 (A1) thru | or FIG. 1 (C3), the rolling ball bearing 2 is arrange | positioned in the recessed part 1a of the bearing housing 1, and the rotating shaft 3 is supported on the center axis | shaft of the rolling ball bearing 2. In FIG. The rolling ball bearing 2 is rotatably held by a holder between a ring-shaped outer ring 2a, a ring-shaped inner ring 2b having a smaller diameter than the outer ring 2a and arranged concentrically, and the outer ring 2a and the inner ring 2b. It is constituted by a ball 2c. The rolling ball bearing 2 is fitted into the recess 1a of the bearing housing 1 and the end surface of the outer ring 2a is fitted into the recess 1a from the opening end surface 1b of the recess 1a by the housing depth L. Yes. The rolling ball bearing 2 supports the rotating shaft 3 rotatably by an inner ring 2b. φ represents the outer diameter of the rolling ball bearing 2. The rotating shaft 3 supports the rotor of the motor and is driven to rotate by a rotating magnetic field generated between the rotating shaft 3 and the stator.

  Reference numeral 4 denotes a caulking punch. As shown in FIGS. 2 and 3, the depth of the housing is adjusted by aligning the blade edge with the so-called shoulder of the open end face 1b in the vicinity of the recess 1a (m is about 0.2 mm) of the bearing housing 1. The caulking punch 4 is pushed into the L with a pushing amount d. The edge angle of the caulking punch 4 is such that the recess 1a side has a width of n (n is about 0.3 mm) and is formed at an angle θ (θ = 45 ° to 50 °), and the outer peripheral side of the bearing housing 1 is p (p = 0. 1 to 0.15 mm) and an angle α (α = 15 to 30 °).

When the caulking process is performed, the bearing housing 1 is positioned by the centering jig 5, the bearing 2 is inserted into the recess 1 a of the bearing housing 1, and the shoulder of the bearing housing 1 is connected to the inner diameter of the bearing housing 1 by the caulking punch 4. Caulking is performed at the same time on the circumference with increased coaxiality. As shown in FIG. 4A, the caulking process may be performed in four parts in a rotationally symmetrical manner as shown in FIG. As shown in c), the caulking process may be performed in three rotations symmetrically.
By the main processing described above, the plastic processing portion and the inner diameter contraction portion 1e shown in FIGS. 1B2 and 1B3 are generated, and the bearing 2 is prevented from coming off and rotating in the thrust direction. By adjusting the L dimension in the figure, the function obtained as a result of plastic working can be changed as shown in FIGS. 1 (A3) to 1 (C3). In order to form the plastic working portion 1e shown in FIG. 1 (B2), (A) the housing base material of the bearing housing 1, (B) the dimension of the housing depth L, (C) the caulking punch cutting edge angle θ dimension, (D) The outer diameter φ dimension of the rolling ball bearing 2 and (E) the push-in amount d dimension are appropriately selected.

  As described above, (A) housing base material of bearing housing 1, (B) housing depth L, (C) caulking punch edge angle θ dimension, (D) outer diameter φ dimension of rolling ball bearing 2, (E) By adjusting the push-in amount d dimension, the fixed state of FIG. 1 (B2) can be created. And, the original action in the fixed state of the present application is “the bearing 2 can be fixed without backlash in the thrust direction.”, “The plastic working portion (or inner diameter shrinkage) 0.2 to 0.3 mm below the caulking position. (Part) 1e is formed, and a tightening allowance can be given after assembly ".

  Table 2 compares the bearing fixing structure of the present invention with the conventional fixing structure shown in Table 1 in terms of thrust fixing strength, assemblability, axial clearance, space saving, countermeasure against creep, and cost. It is clear that the fixing structure of the present invention is excellent in almost all items.

By adjusting the L dimension as shown in Table 3, it is possible to selectively use the direction in which the bearing 2 is to be fixed and the restraining force in the state A to the state C in FIG. It is also possible to adjust the stress by reducing the push-in amount d dimension as shown in FIGS. 5A1 to 5A3, and by making the caulking punch edge angle θ as sharp as shown in FIGS. 5B1 to 5B3. .
Table 3 shows an example in which an aluminum alloy A6063 is used as the housing material. A6063 is an alloy (Al-Mg-Si type) having excellent extrusion processability, good corrosion resistance and surface treatment, and capable of producing various shapes and mold materials.

FIG. 6 shows another embodiment of the present invention in which the same parts as those in FIG. 1 are denoted by the same reference numerals. In this case, a grooved bearing 2 ′ in which a groove 2d is formed in the outer ring 2a of the ball bearing 2 is shown. It is what was used.
In this embodiment, when plastic working is performed by the caulking punch 4, the plastic working portion 1e of the bearing housing 1 enters the groove 2d and fixes the grooved bearing 2 '.
Thereby, grooved bearing 2 'can be fixed more firmly. As described above, by arbitrarily controlling the inner diameter contraction position and the inner diameter contraction stress amount, the bearing can be fixed in a space-saving manner.

According to the first and second embodiments, it is possible to provide an inexpensive bearing fixing method without generating a backlash in the thrust direction for fixing the bearing and without using small parts or auxiliary materials.
Further, since the bearing housing 1 is made of a material that can be plastically processed, the caulking process can be easily performed.
Furthermore, since caulking is simultaneously performed along the circumferential direction by the caulking punch 4, the bearing can be reliably held by the plastic processing portion 1e.
Furthermore, since the housing depth, the caulking punch cross-sectional shape, and the caulking punch push-in amount are set for each material of the bearing housing 1, the bearing can be reliably held by the optimal plastic working portion 1e.
Further, the opening end portion of the recess 1a of the bearing housing 1 is caulked to the inner diameter side, and the outer ring end surface of the bearing 2 is locked by the plastic processing portion 1e of the bearing housing 1. The bearing 2 can be fixed to the base.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, the present invention is applied to a rolling bearing that supports a rotating shaft of a rotating electrical machine such as a motor. Needless to say, the present invention can also be applied to fixing of a rolling bearing to be supported.

DESCRIPTION OF SYMBOLS 1 Bearing housing 1a Concave part 1e Plastic processing part 2 Rolling ball bearing 2a Outer ring 2b Inner ring 2c Ball 2d Outer ring groove 3 Rotating shaft 4 Caulking punch 5 Centering jig

Claims (5)

In a method of fixing a bearing that supports a rotating shaft or the like of an electric motor in a bearing housing, the bearing is inserted into a recess of the bearing housing, and the opening end of the recess of the bearing housing is caulked along the peripheral edge of the bearing. A method for fixing a bearing, wherein the outer ring end face of the bearing is locked by a plastic working portion of the bearing housing by caulking to the inner diameter side by machining. The bearing fixing method according to claim 1, wherein the bearing housing that holds the bearing is made of a plastically workable material. The bearing fixing method according to claim 1 or 2, wherein a shoulder portion provided at a peripheral edge of the concave portion of the bearing housing is caulked along a circumferential direction with a caulking punch having a sharp cross section. 4. The plastic working portion is formed by optimizing three elements of a housing depth, a caulking punch cross-sectional shape, and a caulking punch pressing amount for each material of the bearing housing. 5. The bearing fixing method described. In a structure in which a bearing that supports a rotating shaft or the like of an electric motor is fixed in a bearing housing, an opening end portion of the concave portion of the bearing housing is caulked along a peripheral edge portion of the bearing inserted into the concave portion provided in the bearing housing. A bearing fixing structure characterized in that the outer ring end face of the bearing is locked by a plastic working portion of the bearing housing by caulking to the inner diameter side by machining.

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