JPH0648179Y2 - spindle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a spindle, more specifically to a spindle suitable for use in a video cassette recorder or a disk drive device.

(Prior Art and Problems Thereof) Conventionally, as this kind of spindle, those shown in FIGS. 6 and 7 have been used.

Specifically, in the case of FIG. 6, as shown in the figure, a pair of radial ball bearings 21 are provided above and below the spindle body 20,
22 in which the shaft 1'and the pulley 23 are fixed in advance are inserted into the inner rings of the radial ball bearings 21 and 22, and fixed while adjusting the play of the bearing bush using the fixing sleeve 24. is there.

Then, when assembling this, in order to satisfy the runout accuracy when rotating the pulley 23, the radial ball bearing
There is no choice but to make the bearing mounting parts of 21, 22, shaft 1 and spindle highly accurate. As a result, productivity is low,
This is a cause of high cost, including the number of assembly steps.

In the case of FIG. 7, outer races 31, 32 are arranged on the upper and lower sides as shown in FIG. 7 (b), the inner ring referred to as a radial ball bearing is eliminated, and a ball transfer surface is formed on the shaft 1. The bearing unit 30 in which the spring 6 is arranged between 32 is assembled as shown in FIG.

When assembling this product, since the bearing unit 30 is a constant pressure preload bearing unit, either the outer races 31 and 32 should be glued and fixed together, or one side should be press-fitted and one side should be glued as is often done. I have to. Therefore, holes 33 for injecting the adhesive must be provided.

In the case of FIG. 7, however, the bearing unit 30 has a high precision in advance as compared with the case of FIG.

Therefore, in order to improve these problems of the prior art, a spindle of the same kind having various advantages is disclosed in Japanese Utility Model Application No. 60-1.
Although already proposed by the applicant as 62972 and Japanese Patent Application No. 61-57328, the content of this application is that the shape of the outer race is almost the same as the radial ball bearing which is already mass-produced, and This makes it possible to utilize production equipment.

Fig. 5 shows the same kind of spindle,
In FIG. 5 (a), the ball transfer surface of the outer race 35 is tapered, in FIG. 5 (b), the ball transfer surface is concave spherical, and in FIG. 5 it is convex spherical.

(Means for Solving the Problem) The present invention has been proposed in view of the above points, and an object of the present invention is to keep the preload on the ball substantially constant even if the load fluctuates and maintain a suitable rigidity. To achieve highly accurate rotary motion, improve assembly accuracy, and reduce costs, and to utilize the existing production equipment described above and provide products that are close to the existing usage records in each industrial field. By
To supply such spindles to the industry faster.

That is, in order to achieve the above object, the present invention provides a substantially cylindrical shaft having two concave ball receiving portions formed in its outer peripheral portion for receiving a part of a ball, and a plurality of shafts incorporated in the ball receiving portion. Balls, two outer races that are in contact with the balls and are inclined in one axial direction, and are arranged in openings of the transfer surfaces so as to face each other, and the two outer races. In a spindle used for a VTR recorder or a disk drive device, which includes an outer race and a spring that springs and holds the outer race at all times outward, a shield plate is provided on each open end side of the outer race. At the same time, a dustproof and reinforced portion is integrally formed at the inner end in the axial direction to have a substantially L-shaped cross section, and the outer peripheral portions of the two outer races facing each other have a circumferential direction. The gist is that the center of the spring and the center of the shaft are made to coincide by forming a spring holding portion composed of a concave portion formed in the opposite direction.

(Operation) The spindle of the present invention incorporates balls into two concave ball receiving portions formed on the outer peripheral portion of the shaft, and two outer races having a tapered or concave R transfer surface that abuts on the balls are provided on the transfer surface. By arranging the openings so that they face each other outward, and installing a spring between the outer race and the outer race to apply pressure to the ball, the pressure on the ball is almost constant even if the load changes. Therefore, it is possible to supply a rotational motion with high accuracy by exhibiting suitable rigidity.

Moreover, since a shield plate is provided on each opening end side of the outer race and a dustproof and reinforcing portion is integrally formed on the inner end in the axial direction, dust and dirt enter the inside of the bearing even at the semi-finished stage. There is no fear and it is convenient for storage. Furthermore,
By aligning the center of the spring with the center of the shaft, the pressure applied to the outer race can be made uniform.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first embodiment of the present invention, in which a concave ball receiving portion 2 for receiving balls is provided on the outer circumference of a shaft 1.
Are formed so as to be separated from each other at two places, and an appropriate number of balls 3 are arranged in the ball receiving portion 2, respectively, and an outer race 5 having a transfer surface 4 that abuts on the balls 3 is supported by the balls 3 and is rotated by the shaft 1. It is installed freely. The transfer surface 4 of the outer race 5 is formed as an inclined surface that expands to one side in the axial direction. In the first embodiment, the inclined surface is a linear taper surface. The outer races 5 are attached to each other so that the inclination directions of the transfer surfaces 4 spread outward, and a coil-shaped spring 6 is provided between the outer races 5.
It has been ejected and held outward. Reference numeral 7 is a seal for preventing foreign matter from entering, and 8 is a housing to which the spindle of this embodiment is attached.

Further, a dustproof and reinforcing portion 5a is integrally formed at each axially inner end portion of the outer race 5 to have a substantially L-shaped cross section, and a spring is provided at the outer peripheral portions of the opposite end surfaces of the two outer races 5. The holding portion 5b is formed.

With these configurations, the spindle according to the first embodiment has the outer race 5 with the elastic force of the spring 6 adjusted in advance.
Is pushed outward so that the taper surface of the transfer surface 4 presses the ball 3 with no gap. At this time, the spring 6 is attached to the spring holding portion 5b formed by a circumferential recess formed in a part of the outer peripheral surface of the outer race 5 so that the center of the spring 6 and the center of the shaft 1 are aligned with each other. The pressure applied to the outer race 5 can be made uniform. Further, since the ball 3 is restricted from rolling in the axial direction by the ball receiving portion 2 of the shaft 1, it is possible to apply a suitable preload to the contact portion of the ball 3.

As described above, in the first embodiment, the outer race 5 has an L-shaped cross section to increase the rigidity, thereby improving the roundness and the super-finishing accuracy. Further, the action of the spring 6 keeps the preload on the ball 3 substantially constant despite the change of the load, so that the rotational motion with high accuracy can be supplied.

Further, due to the seal 7 and the dustproof / reinforced portion 5α, there is no danger that dust or dirt will enter the inside of the outer race 5, and therefore, it can be easily stored even in a semi-finished state.

Next, FIG. 2 shows a second embodiment of the present invention. In the second embodiment, the transfer surface 14 of the outer race 15 is formed as a concave inclined surface. Further, a dustproof and reinforcing portion 15 is integrally formed at each axial inner end portion of the outer race 15 and has a substantially L-shaped cross section. Further, a spring holding portion is provided on the outer peripheral portions of the opposite end surfaces of the two outer races 15. Forming 15b. Since the other parts have the same structure as the first embodiment as is apparent from the drawings, the same members are designated by the same reference numerals and the description thereof will be omitted.

The second embodiment can obtain the same action and effect as the first embodiment, but in addition, since the transfer surface 14 is made concave, the load capacity becomes large, and it is possible to supply a rotary motion with a higher weight.

Next, FIG. 3 shows a third embodiment of the present invention. In the third embodiment, the bearing housing 9 is fitted to the spindle of the first embodiment to form a unit. Since the structure of the spindle body is the same as that of the first embodiment as is apparent from the drawings, the same members are designated by the same reference numerals and the description thereof will be omitted.

In addition to the same operation and effect as the first embodiment, the third embodiment has a spindle incorporated in the bearing housing 9, whereby the entire spindle can be assembled and adjusted in advance. Shaft 1,
Ball 3, outer race 5, bearing housing 9
The accuracy of the mating member 10 to which the spindle body is attached does not need to be so high, and despite the fact that the number of parts is increased by one, it is excellent in terms of the total number of assembly steps and cost.

Next, FIG. 4 shows a fourth embodiment of the present invention. In the fourth embodiment, similarly to the third embodiment, the bearing housing 9 is fitted to the spindle of the second embodiment to form a unit. . Since the structure of the spindle body is the same as that of the second embodiment as is apparent from the drawings, the same members are designated by the same reference numerals and the description thereof will be omitted.

In addition to the same operation and effect as the second embodiment, the fourth embodiment can also be assembled and adjusted in advance by incorporating the spindle into the bearing housing 9 as in the third embodiment. It becomes possible, and the performance of the spindle is determined by the accuracy of the shaft 1, the ball 3, the outer race 15, and the bearing housing 9, and the mating member 10 to which the spindle body is attached does not require much accuracy, and the number of parts has increased by one. Nevertheless, it is excellent in terms of overall assembly man-hours and cost.

As described above, according to the present invention, the roundness and the super-finishing accuracy can be improved by increasing the rigidity by making the cross-sectional shape of the outer race L-shaped. Costs can be reduced while preventing dust from entering. In addition, a spring holding part is formed on the outer peripheral part of the end face of the outer race, and the action of the large diameter spring attached here keeps the preload on the ball substantially constant despite the fluctuation of the load, enabling accurate rotation. There are effects such as exercise.

[Brief description of drawings]

1 is a sectional view of a first embodiment of the present invention, FIG. 2 is a sectional view of a second embodiment of the present invention, FIG. 3 is a sectional view of a third embodiment of the present invention, and FIG. 4 is a book. FIG. 5 is a cross-sectional view of a fourth embodiment of the invention, FIG. 5 is a prior art example already proposed by the present inventor, and FIG.
FIG. 7 and FIG. 7 are conventional examples. 1 is a shaft, 2 is a ball receiving part, 3 is a ball, 4 and 14 are transfer surfaces, 5 and 15 are outer races, 5a and 15a are dustproof and reinforcing parts 5b and 15b are spring holding parts, and 6 is a spring.

Claims (2)

[Scope of utility model registration request] 1. A shaft having a substantially cylindrical shape having two recessed ball receiving portions formed on its outer peripheral portion for receiving a part of the ball, a plurality of balls incorporated in the ball receiving portion, and the ball. Interposing between the two outer races, which are in contact with each other and have a transfer surface inclined to one side in the axial direction, and whose opening portions of the transfer surface are arranged to face each other, and between the two outer races, In spindles used in VTR recorders and disk drive devices that consist of springs that constantly spring and hold the outer race outward, a shield plate is provided on each open end side of the outer race, and an inner end in the axial direction is provided. Has a substantially L-shaped cross section in which a dustproof and reinforced portion is integrally formed, and a bar formed of a concave portion formed in the circumferential direction on the outer peripheral portions of the opposing end faces of the two outer races. A spindle characterized in that the center of the spring is made to coincide with the center of the shaft by forming a retaining portion. 2. The spindle according to claim 1, wherein a substantially cylindrical bearing housing is provided on the outer periphery of the outer race for facilitating confirmation of performance such as assembly and ball transfer.