JPS61201918A - Bearing device - Google Patents

Abstract

PURPOSE:To prevent in space or the like the looseness of a rotary shaft and to ensure its smooth rotation, by rotatablyt fitting the rotary shaft to outer rings mounted to bearing beds and supporting the peripheral surface of the rotary shaft through spherical inner rings. CONSTITUTION:A rotary shaft 3 integrally fits to its both ends an inner ring 7 forming its peripheral surface by a spherical surface 6, and a bracket 5 protrusively provides bearing beds 8a, 8b so as to surround these inner rings 7. These bearing beds 8a, 8b fit outer rings 10a, 10b forming their internal peripheral surface by a spherical surface 9 larger than the spherical surface 6. And a bearing device, integrally fitting one outer ring 10a to the bearing bed 8a and slidably fitting in a parallel direction to the rotary shaft the outer ring 10b to the bearing bed 8b, provides between said outer ring 10b and the bearing bed 8b a compression spring 11 resiliently pressing the outer ring 10b in a thrust direction.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is directed to a shaft conventional technology capable of smoothly supporting a rotating shaft without rattling even under severe thermal expansion changes. The antenna flip-up mechanism, the deaf-opening configuration, the solar array paddle deployment mechanism, etc. built into the aircraft that will be launched in the near future are required to have extremely high reliability, and accidents such as malfunction cannot be tolerated.

Generally speaking, things that must be taken into consideration in space regarding single rotation systems are that lubricating oil cannot be used and that thermal changes are extremely large. Because of this drawback, the rotating shaft in the above-mentioned flip-up mechanism or long-range mechanism is usually a self-aligning shaft such as a spherical bearing of the all-over transmission type.

Problems to be Solved by the Invention> If there is a difference in material between the rotating system and the stationary system that supports it, the amount of thermal deformation between them will differ due to differences in heat conduction, coefficient of thermal expansion, etc. This causes excessive stress on the bearing part. If there is a temperature change of a certain degree (degrees Celsius),
Since the deformation in the thrust direction and radial direction is compounded and appears large, it is very difficult to accurately grasp the amount of deformation.As a result, bearings may seize or stick, preventing normal rotation of the rotating shaft. There was a risk that it would become impossible.

In order to prevent the rotary shaft from becoming unable to rotate due to thermal deformation, it is possible to set a large bearing clearance, but such clearance will inevitably appear as bearing rattling, so This will cause positioning errors. In particular, since there is no gravity in outer space, small disturbances can cause small displacements of the rotating system, making it impossible to achieve highly accurate positioning.

Based on this knowledge, it is an object of the present invention to provide a highly reliable bearing device that can rotate smoothly even in outer space without rattling the rotating shaft.

Means for Solving Problems> A bearing device according to the present invention includes an inner ring having a spherical outer circumferential surface and attached to a rotating shaft, and a spherical surface on which the outer circumferential surface of the inner ring rotatably abuts. an outer ring formed on a surface and supported by a bearing pedestal, and an outer ring interposed between the outer ring and the bearing pedestal and between the inner ring and the rotating shaft; and an elastic member that elastically displaces at least one of the rotational shafts in a direction parallel to the rotation axis.

Function: The rotating shaft is supported via an inner ring that is rotatably fitted to an outer ring attached to a bearing stand, and rotates together with the inner ring while self-centering with respect to the outer ring. If large thermal expansion occurs in these, the elastic member elastically deforms and displaces the inner ring and outer ring relative to each other in the longitudinal direction of the rotating shaft, thereby preventing the contact pressure between the inner ring and outer ring from becoming excessive. to ensure that the rotating shaft always rotates without rattling.

Embodiment As shown in FIG. 1 showing the structure of the main part of an embodiment in which the present invention is applied to a paddle deploying device, and FIG. 2 showing the overall appearance, a pair of On pillar 2 of
The rotating shafts 3 are integrally fixed to each other in a straight line, and the bearing device of this embodiment is installed between the rotating shafts 3 and a pair of brackets 5 protruding from the base 4. Intervened. An inner ring 7 whose outer peripheral surface is formed of a spherical surface 6 with a constant radius of curvature is integrally fitted to both ends of the rotating shaft 30, and bearing stands 8a and 8b are mounted on a bracket 5 so as to surround these inner rings 7.
It is installed protrudingly. These bearing stands ga, 8b have an inner peripheral surface formed of a spherical surface 9 with a constant radius of curvature larger than that of the spherical surface 6.
outer ring 10a.

10b are fitted, and the inner ring 70 spherical surface 68 these outer rings 10
The spherical surfaces 9 of a and 10 b rotatably support and have a self-centering function. One outer ring 10a is a bearing stand 8a
The other outer ring 10b is fitted into the bearing stand 8b so as to be slidable in a direction parallel to the rotating shaft 3 (in the left-right direction in FIG. 1). A compression spring 11 that elastically presses the outer ring fob in the thrust direction is provided between the outer ring lOb and the bearing stand 8b. t), the contact pressure between the inner ring 7 and the outer rings 10a and lOb is 9 compression spring 1
It is set based on the spring force of 1.

Therefore, due to the operation of a drive source such as a motor or a spring (not shown), the paddle l rotates around the rotating shaft 3, and the spherical surface 6 of the inner ring 7 and the outer ring 10a.

It is in line contact with the spherical surface 9 of 10b (due to the difference in radius of curvature) to maintain low frictional resistance and perform smooth rotation. On the other hand, when the rotating shaft 3 is deformed in the thrust direction and radial direction due to thermal expansion or the like, the outer ring 10b resists the spring force of the compression spring 11 due to the displacement of the inner ring 7, as shown in FIG. , is pushed back to the right and slides inside the bearing stand 8b, and the inner ring 7 and outer ring lOa *
10b is displaced so that the contact pressure with b is not excessive. As a result, the inner ring 7 and the outer rings 10a, 10b are always in contact with each other, allowing smooth rotation without wobbling even when there is a large temperature change.

Note that in this embodiment, the outer ring 10b is slidable on the bearing stand 8b in a direction parallel to the rotating shaft 3;
The inner ring 7 in contact with the rotating shaft 31 may be slidably fitted in a direction parallel to the rotating shaft 31 and pressed against the outer ring via an elastic member such as a disc spring or a coil spring. It is of course possible to adopt the same structure on one side of the bearing stand 8a. In addition, the sliding surface and the member 1 having this sliding surface, such as the inner ring 7, middle bearing pedestal 8b, and outer ring 10a, are made of a material with a low coefficient of friction such as fluororesin, or molybdenum disulfide, tungsten disulfide, etc. When formed from a material with excellent self-lubricating performance.

Effective in reducing rotational resistance.

In the embodiment described above, the spherical surfaces 6 and 9 were each formed with a single radius of curvature, but as shown in FIG. The inner peripheral surface of the outer ring 13 attached to the bearing stand 12 and the rotating shaft 14 are fitted together.
Spherical surfaces 16, 17, 18, and 19 with different radii of curvature are formed on the outer circumferential surface of the circular ring 15. When the thrust load is large, the spherical surfaces 16 and 18 with the small radius of curvature are brought into contact with each other to reduce the radial load. If the radius of curvature is large, spherical surfaces 17 and 19 with a large radius of curvature may be brought into contact.

Further, as shown in FIG. 4 showing the cross-sectional structure of another embodiment of the bearing device according to the present invention, an outer ring 22 rotatably supports an inner ring 21 attached to a rotating shaft 20 as one elastic member, and a bearing stand. It is also possible to displace the outer ring 22 in a direction parallel to the rotating shaft 20 by using a leaf spring 24 that connects the outer ring 23 with the rotary shaft 23 by elastic deformation of the leaf spring 24.

In this case, depending on the situation, the inner ring 21 may be attached to the rotating shaft 20 by integrating the outer ring 25 and the leaf spring 26 as shown in FIG. 5, which shows the cross-sectional structure of another embodiment of the present invention. It is also possible to have a structure in which the inner ring 29, which is made of and fixed to the bearing stand 27 and is fitted onto the rotating shaft 28, is clamped between the rotating shaft 28 and the outer ring 25.
In the second case, there is a major f which is particularly effective against thrust loads. Furthermore, as shown in FIG. 6, which shows the front surface structure of still another embodiment of the present invention, the rotating shaft 30
-Inner ring 31 is integrally formed on the shaft end of real 1, and leaf spring
Alternatively, the inner ring 31 may be brought into contact with and rotated by the outer ring 33 which is integrated with the inner ring 33. Inner ring 29.31 and outer ring 25 shown in Fig. 5 and Fig. 6
．． 23゜shi 2゜shiro.

<Effects of the Invention> According to the bearing device of the present invention, the inner ring and the outer ring are always in contact with each other due to the spring force of the elastic member, and when thermal deformation due to a large temperature change occurs, the elastic member is elastically deformed. Since the contact state between the inner ring and the outer ring is maintained normally, the rotating shaft can be rotated with stable rotational torque, and a highly reliable bearing device that is not affected by external conditions can be obtained.

) Brief explanation [The figure is a cross-sectional view of the bottom of an embodiment of the bearing device according to the present invention,
FIG. 2 shows the overall appearance, and FIGS. 3 to 6 are sectional views each showing the structure of one example of the present invention.

The numbers in the diagram are 3.14, 20, 29, 30 axis, 6, 9
, 16/'-19 is a spherical surface, 7, 15゜29.31 is an inner ring, 8a, 8b, 12゜27 is a bearing stand, 10a, 10b,
13゜25.33mm outer ring, 11 is compression 1', 24
゜32 is a leaf spring.

Claims (1)

[Claims] an inner ring having a spherical outer circumferential surface and attached to a rotating shaft; an outer ring having an inner circumferential surface formed with a spherical surface against which the outer circumferential surface of the inner ring rotatably contacts; and an outer ring supported by a bearing stand; an elastic member that is interposed between at least one of the bearing stand and between the inner ring and the rotating shaft to elastically displace at least one of the outer ring and the inner ring in a direction parallel to the rotating shaft; A bearing device equipped with.