JP2897114B2 - Composite bearing device and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite bearing device used for rotating parts of computer equipment and peripheral equipment thereof, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a conventional device using two ball bearings of a bearing device mounted on a shaft of a rotating part in a computer device or a peripheral device thereof, as shown in FIG. In addition to B, cylindrical spacers C are separately manufactured, and these parts are delivered to the user, and the user assembles these parts to the shaft D.

[0003]

As described above, the conventional bearing device requires the user to assemble two ball bearings on the shaft via the spacer, but has the following problems.

(A) The shaft must be manufactured in accordance with the inner diameter of the inner ring of the ball bearing, and the shaft is limited in rigidity. (b) It is necessary to finish the parallelism and flatness of both end faces of the spacer with high precision. (c) The contact between both end surfaces of the spacer and the end surface of the outer ring of the ball bearing must be made uniform, and processing and work for that purpose are not easy.

[0005] The present invention has solved such a problem, and has made it possible for a user to provide a composite bearing device that can be used as it is in a rotating portion of various rotating devices.

[0006]

According to a first aspect of the present invention, there is provided a composite bearing device comprising: an outer peripheral rolling groove formed on an inner peripheral surface of an outer race; and a large diameter of a two-stage shaft having a large diameter portion and a small diameter portion. A ball is filled between an inner peripheral rolling groove formed on the outer periphery of the inner ring and an inner peripheral rolling groove formed on the outer periphery of the inner ring fitted in the small diameter portion of the two-stage shaft, and an end of a sleeve outer ring formed of a cylindrical body. The ball is filled between the inner peripheral surface and the outer peripheral rolling groove.

The first means includes an outer peripheral rolling groove formed on an inner peripheral surface of an outer ring, and an inner peripheral rolling groove formed on an outer periphery of a large diameter portion of a two-stage shaft having a large diameter portion and a small diameter portion. An inner peripheral rolling groove formed on the outer periphery of an inner ring slidably fitted in the small diameter portion of the two-stage shaft, and an outer peripheral rolling formed on an inner end portion of a sleeve outer ring formed of a cylindrical body A ball is filled between the groove and a proper preload is applied to either the outer end of the inner ring or the outer ring of the sleeve, and the inner ring is fixed to the small diameter portion of the two-stage shaft in a state where the preload is applied. .

The composite bearing device of the second means is characterized in that an outer peripheral rolling groove formed on an inner peripheral surface of one end of a sleeve outer ring formed of a cylindrical body;
The inner ring of a ball bearing in which a ball is filled between an inner peripheral rolling groove formed on an outer periphery of a large diameter portion of a two-stage shaft having a large diameter portion and a small diameter portion, and a ball is filled between an inner ring and an outer ring, is provided. It is fitted to the small diameter part of the step shaft.

In the second means, an outer peripheral rolling groove formed on an inner peripheral surface of one end of a sleeve outer ring made of a cylindrical body and a large diameter portion outer periphery of a two-stage shaft having a large diameter portion and a small diameter portion are formed. The ball is filled between the inner peripheral rolling groove and the inner ring of the ball bearing filled with the ball between the inner ring and the outer ring is slidably fitted to the small diameter portion of the two-stage shaft. An appropriate preload is applied to the outer end of the two-stage shaft, and the inner ring is fixed to the small-diameter portion of the two-stage shaft in a state where the preload is applied.

In the first embodiment, all the balls have the same diameter by making the outer diameter of the inner ring fitted to the small diameter portion of the two-stage shaft the same as the large diameter portion of the two-stage shaft. In the second type, the outer diameter of the inner ring of the ball bearing is the same as the outer diameter of the large diameter portion of the two-stage shaft, and the outer ring has the same outer diameter and inner diameter as the outer diameter and the inner diameter of the sleeve outer ring. By doing so, all balls are of the same diameter.

[0011]

FIG. 1 shows a first embodiment according to the present invention. In the figure, reference numeral 1 denotes a two-stage shaft having a large diameter portion 1a and a small diameter portion 1b, and an inner peripheral rolling groove 2a is formed on the outer periphery of the large diameter portion. Reference numeral 3 denotes an outer ring, which is filled with a ball 4 between an outer peripheral rolling groove 2b formed on an inner peripheral surface thereof and the inner peripheral rolling groove 2a of the large diameter shaft, and assembled to a large diameter shaft portion.

Reference numeral 5 denotes a sleeve outer ring surrounding the two-stage shaft, which has an outer peripheral rolling groove 6b formed on an inner peripheral surface at an outer end portion (right end in FIG. 1). A ball 8a is filled between the inner ring 7a and the inner peripheral rolling groove 6a formed on the outer periphery of the inner ring 7a fitted to the small diameter portion, and assembled to a two-stage shaft. The outer diameter of the inner ring 7a fitted to the small diameter portion 1b of the two-stage shaft 1 is the same as the large diameter portion 1a of the two-stage shaft, so that the balls 4, 8a are all of the same diameter.

In this embodiment, for example, the inner ring 7a is slidably fitted in advance on the small diameter portion of the two-stage shaft, and then an appropriate preload (preload) is applied to the inner ring from the outer end face (the right end face in FIG. 1). Then, in a state where the preload is applied, the inner ring 7a is fixed to the small-diameter portion of the two-stage shaft with an adhesive or the like, and the outer ring,
Assemble the sleeve outer ring and inner ring to the two-stage shaft.

FIG. 2 shows a second embodiment according to the present invention.
Also in this embodiment, the inner peripheral rolling groove 2a is formed on the outer periphery of the large diameter portion of the two-stage shaft 1. An outer peripheral rolling groove 2b is formed on the inner peripheral surface of one end (the left end in the figure) of the sleeve outer ring 5 surrounding the two-stage shaft, and the outer peripheral rolling groove 2b and the inner peripheral rolling of the shaft large diameter portion are formed. The ball 4 is filled in between the moving groove 2a.

An inner ring 7a and an outer ring 7b are provided at the small diameter portion of the two-stage shaft.
And the inner ring 7a of the ball bearing 7 filled with the ball 8b is fitted and fixed between the inner and outer rings. The outer diameter of the inner ring 7a of the ball bearing 7 is made the same as the outer diameter of the large-diameter portion 1a of the two-stage shaft 1, and the outer diameter and the inner diameter of the outer ring 7b are the same as the outer diameter and the inner diameter of the sleeve outer ring 5, respectively. The balls 4 and 8b have the same diameter by having the same diameter.

In this embodiment, for example, an inner ring 7a of a ball bearing is slidably fitted in a small diameter portion of a two-stage shaft in advance, and then an appropriate preload (from the outer end face (right end face in FIG. 1)) is applied to the inner ring 7a. The inner ring 7a is fixed to the small-diameter portion of the two-stage shaft with an adhesive or the like while the preload is applied, and the outer ring, the sleeve outer ring, and the inner ring are assembled to the two-stage shaft.

Reference numerals 9a and 9b in the drawings denote respective rolling grooves of the inner and outer races of the ball bearing, and reference numeral 10 denotes a ball retainer. In the first and second embodiments described above, all the balls have the same diameter, but balls having different diameters may be used on the large diameter portion side and the small diameter portion side.

[0018]

In the present invention, one end of the sleeve acts as an outer ring, and the sleeve is a composite sleeve outer ring in which one outer ring is integrally formed. is there.

(A) The composite bearing device of the present invention comprises an inner ring, an outer ring,
Since the sleeve outer ring and the ball are assembled to the shaft, the user does not need to assemble these parts, and can be attached to the corresponding device by inserting and fixing the sleeve outer ring into the cylinder of the rotating body. . (b) In the present invention, since the inner peripheral rolling groove is formed directly on the outer periphery of the large diameter portion of the two-stage shaft, the conventional inner ring is unnecessary,
Accordingly, the shaft can be made partly larger in diameter to form a two-stage shaft, and the shaft rigidity can be increased. (c) Since the shaft can be made to have a large rigidity with a large diameter part, the resonance (resonance point) of the spindle motor for OA equipment incorporating this device will be high, and it will not be possible to use other parts in the equipment. Can be prevented, and the reliability of the device can be improved. (d) Only one conventional ball bearing is required, and therefore only one inner ring is required, and the number of parts can be reduced. (e) Since the outer ring of the sleeve also serves as the spacer, the conventional spacer is unnecessary, and the number of parts can be reduced. (f) The overall length in the axial direction can be shortened, and the size of equipment provided with the bearings can be reduced, as compared with a conventional one in which ball bearings are attached to both ends of the spacer. (g) The sleeve outer ring can be manufactured with high precision by the bearing manufacturer, and the end surface can be finished only on the ball bearing mounting side, reducing the number of manufacturing steps.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a composite bearing device according to the present invention.

FIG. 2 is a longitudinal sectional view showing a second embodiment of the composite bearing device according to the present invention.

3A and 3B show a configuration of a conventional bearing, in which FIG. 3A is a longitudinal sectional view showing a ball bearing and a spacer before being assembled, and FIG. 3B is a longitudinal sectional view showing a state where the ball bearing and the spacer are assembled on a shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Two-stage shaft 2a Inner rolling groove 2b Outer rolling groove 3 Outer ring 4 Ball 5 Sleeve outer ring 6a Inner rolling groove 6b Outer rolling groove 7 Ball bearing 7a Inner ring 7b Outer ring 8a, 8b Ball 9a, 9b Rolling groove 10 Ball retainer

Claims (4)

(57) [Claims] 1. A ball is filled between an outer peripheral rolling groove formed on an inner peripheral surface of an outer race and an inner peripheral rolling groove formed on an outer periphery of a large diameter portion of a two-stage shaft having a large diameter portion and a small diameter portion. A ball is filled between an inner peripheral rolling groove formed on the outer periphery of the inner ring fitted to the small diameter portion of the two-stage shaft and an outer peripheral rolling groove formed on the inner surface of the end of the sleeve outer ring formed of a cylindrical body. Composite bearing device. 2. A ball is filled between an outer peripheral rolling groove formed on an inner peripheral surface of an outer ring and an inner peripheral rolling groove formed on an outer periphery of a large diameter portion of a two-stage shaft having a large diameter portion and a small diameter portion. A ball is provided between an inner peripheral rolling groove formed on the outer periphery of the inner ring slidably fitted to the small diameter portion of the two-stage shaft and an outer peripheral rolling groove formed on the inner surface of the end of the outer sleeve of the cylindrical body. And a proper preload is applied to either the outer end of the inner ring or the outer ring of the sleeve, and the inner ring is fixed to the small-diameter portion of the two-stage shaft while the preload is applied. Production method. 3. An outer peripheral rolling groove formed on an inner peripheral surface of one end of a sleeve outer ring made of a cylindrical body, and an inner peripheral rolling groove formed on an outer periphery of a large diameter portion of a two-stage shaft having a large diameter portion and a small diameter portion. A ball bearing in which a ball is filled between the inner ring and an outer ring, and an inner ring of the ball bearing is filled with the ball between the inner ring and the outer ring. 4. An outer peripheral rolling groove formed on an inner peripheral surface of one end of a sleeve outer ring made of a cylindrical body, and an inner peripheral rolling groove formed on an outer periphery of a large diameter portion of a two-stage shaft having a large diameter portion and a small diameter portion. Between the inner ring and the outer ring, the inner ring of the ball bearing filled with the ball is slidably fitted to the small diameter portion of the two-stage shaft, and the outer end of either the inner ring or the outer ring of the ball bearing. A method of manufacturing a composite bearing device, wherein an appropriate preload is applied, and the inner ring is fixed to a small-diameter portion of a two-stage shaft in a state where the preload is applied.