JPH086746B2 - Preload compensator for rolling bearings - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a preload compensating device for a rolling bearing, which is capable of automatically adjusting an axial preload or a clearance in accordance with a temperature change.

[Conventional technology]

Rolling bearings, such as angular contact ball bearings and tapered roller bearings, are of a type whose clearance can be adjusted by mounting, so that preload is applied to prevent shaft vibration and the support rigidity is increased. It is also possible.

If the shaft, bearing, and housing are made of different materials, for example, the carbon steel shaft is made of aluminum alloy and the bearing steel tapered roller bearings are used in frontal combination. In addition, due to the difference in the coefficient of linear expansion between the shaft and the housing, the dimensional change of the housing is larger than that of the shaft, and at high temperature, a gap is formed in the tapered roller bearing in the axial direction, causing vibration and noise. On the contrary, at low temperature, axial load is applied and the starting torque and dynamic torque of the shaft increase.

Therefore, various types of preload compensating devices for rolling bearings have been proposed which are used when the linear expansion coefficient of the shaft and the housing are different.

For example, in Japanese Examined Patent Publication No. 39-29381, the spacer is formed of two rings having different linear expansion coefficients, and the contact surfaces of both rings are inclined surfaces to compensate for the change in length due to the heat of the shaft. What to do is shown. In Japanese Utility Model Laid-Open No. 57-55536, there is one in which a disc spring or a corrugated spring is inserted between the housing of a tapered roller bearing and the outer ring of the bearing to absorb the change in the axial clearance due to the temperature rise. It is shown. In addition, Japanese Utility Model Laid-Open No. 58-122017 discloses a shim formed by joining two kinds of kinzoku with different linear expansion coefficients to prevent preload loss during rotation of a tapered roller bearing.
Japanese Utility Model Laid-Open No. 58-61922 discloses that a preload is applied by a coil spring incorporated in the housing with a gap between the outer diameter of the bearing and the housing. Furthermore, Japanese Utility Model Publication No. 60-495 discloses that a corrugated leaf spring is used as a preloading means to correct the play between the shaft and the tapered roller bearing when the vehicle shift lever is in neutral. There is.

[Problems to be solved by the invention]

However, all of the above-described conventional rolling bearing preload compensators have a problem that they cannot be accurately compensated because they are deformed when an axial load is applied.

An object of the present invention is to provide a preload compensating device for a rolling bearing having an extremely large axial rigidity and solve the above problems.

[Means for solving problems]

The present invention for achieving the above object is a preload compensating device for a rolling bearing, which is used by being interposed between a rolling bearing supporting a rotating shaft and a housing of the bearing, and having an annular one end surface. A sliding ring body in which two rings, each of which has a plurality of slopes having the same inclination angle and are intermittently arranged in the circumferential direction, are overlapped with each other so that the slopes are in contact with each other and are rotatable relative to each other.
At least one elastic actuator, one end of which is locked to one ring and the other end of which is deformed in the direction of rotation of the ring in response to temperature changes, to relatively rotate the ring in the circumferential direction. Be prepared.

[Operation] The elastic actuator is deformed in the rotation direction of the ring according to the temperature change. When the actuator is deformed and the temperature rises, for example, the two rings rotate relative to each other in the direction in which the amount of superposition of their slopes decreases. This increases the height (thickness) of the sliding annulus, and compensates for the increase in the axial clearance between the housing and the bearing and the decrease in preload.

Also, when the temperature drops, the rings rotate relative to each other in the direction in which the amount of overlap between the slopes of the rings increases,
The height of the sliding ring is reduced, which reduces the axial clearance between the housing and the bearing and increases the preload.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show an embodiment of the present invention. A tapered roller bearing 2 supporting a rotary shaft 1 made of carbon steel is housed in a housing 3 made of aluminum alloy. The tapered roller bearing 2 can adjust the axial clearance, and a preload compensator 5 is interposed between the housing 3 and one end surface 4 a of the outer ring 4 of the bearing 2.

The magnitude of the preload applied to the bearing 2 is appropriately determined in consideration of the rotation speed of the shaft 1, the load capacity of the bearing 2, the external load, and the like.

The preload compensator 5 is made of metal of the same shape and size.
Sliding ring body 8 in which individual rings 6 and 7 are rotatably stacked in the axial direction, and bimetal, shape memory alloy, synthetic resin, etc., that can be deformed in the relative rotation direction of rings 6 and 7 in response to temperature changes It is composed of an elastic actuator 9.

More specifically, each of the rings 6 and 7 is an annular ring having a square cross section with an outer diameter somewhat smaller than the outer diameter of the bearing outer ring 4, and one end surface thereof has a plurality of gentle slopes having the same inclination angle β. 10 are formed intermittently at regular intervals in the circumferential direction. A flat surface 11 is formed on the top of the gentle slope 10, and the flat top surface 11 is connected to the skirt 10a of the adjacent gentle slope 10. A square groove-shaped notch 6A is provided for the ring 6 and a similar notch 7A is provided for the ring 7 on each end face opposite to the side where the gentle slope 10 is provided. The rings 6 and 7 formed as described above are stacked with their gentle slopes 10 facing each other, and a sliding ring body 8 is obtained.
The height (thickness) h of the obtained sliding ring body 8 is minimized when the overlapping amount of the gentle slopes 10 is the largest, and is increased as the overlapping amount is decreased by the relative rotation of the rings.

In addition, the inclination angle β of the gentle slope 10 is the friction coefficient μ between the slopes.
(Ring material, cleanliness of slope, roughness, lubricant, etc. are taken into consideration) and the following equation tanβ <μ is selected.

The elastic actuator 9 that relatively rotates the sliding ring 8 uses a bimetal having a width t, which is a temperature deformation member, and has an inner diameter r.
Is formed by winding once in a spiral shape, and both ends thereof are provided with attachment portions 13 and 14 which are bent outward, and are ring-shaped as a whole. The opening angle (spiral center angle) θ of the both end mounting portions 13 and 14 shows a change of Δθ according to the expansion and contraction of the bimetal according to the temperature change ΔT.

The one mounting portion 13 is fitted to the notch 6A of one ring 6 of the sliding ring body 8 and the other mounting portion 14 is fitted to the notch 7A of the other ring 7 of the sliding ring body 8 to be mounted. Has been done.

 Next, the operation will be described.

As shown in FIG. 1, the proper preload determined in consideration of the rotational speed, load capacity, external load, etc. of the tapered roller bearing 2 mounted in the housing 3 is applied in the axial direction of the tapered roller bearing 2. . When the temperature rises, the housing 3 expands more due to the difference in linear expansion coefficient between the shaft 1 and the housing 3.

At that time, the elastic actuator 9 of the preload correction device 5 extends in accordance with the temperature increase amount ΔT, and tries to open by Δθ.
The force causes both rings 6, 7 to rotate relative to each other so that the overlap between the gentle slopes 10 is reduced, and therefore the height h of the sliding ring 8 is increased. As a result, the relative rotation is converted into an axial displacement,
The axial clearance based on the difference in expansion amount between the housing 3 and the shaft 1 is corrected, and the decrease in preload can be compensated.

Moreover, in this case, the inclination angle β of the gentle slope 10 and the friction coefficient μ acting between the slopes always have a relationship of tan β <μ, and therefore even if an axial load is applied, the ring of the preload compensator 5 is
No slippage occurs between 6 and 7, and the predetermined height h is maintained.

 FIG. 6 shows another embodiment.

This embodiment differs from the first embodiment in that two elastic actuators 9A and 9B are mounted in combination. That is, the elastic actuator 9A has its mounting ends 13a and 14a.
Are fitted into the notches 6A of the ring 6 and the notches 7A of the other rings 7, respectively, and the elastic actuator 9B
Is attached by fitting its mounting ends 13b and 14b into the notch 6B of the ring 6 and the notch 7B of the other ring 7, respectively.

If combined in this way, a larger displacement force can be applied.

 7 and 8 show still another embodiment.

This embodiment differs from the first and second embodiments in that a plurality of plate-shaped elastic actuators 20 made of bimetal are radially arranged.

That is, the two rings 21 and 22 have the same outer diameter and different inner diameters. The elastic actuator 20 is mounted between the rings 21 and 22 by utilizing the connecting surface 23 that joins the flat surface 11 on the top of the gentle slope 10 and the skirt 10a on the adjacent slope.
One end of the elastic actuator 20 is locked to the connecting surface 23 of the ring 21 having the smaller inner diameter by, for example, a pin 24, and the other end of the elastic actuator 20 is connected to the connecting surface 25 of the ring 22 having the larger inner diameter by a pin (not shown). Is locked in.

The elastic actuator 20 is deformed according to the temperature change to rotate both rings 21 and 22 relative to each other.

In this embodiment, the relative rotation of both rings 21, 22 is made easier.

Although the elastic actuator is made of bimetal in each of the above-described embodiments, the shape memory alloy is not limited to this and may be a shape memory alloy that can be reversibly deformed by temperature.

Further, similarly to the tapered roller bearing shown in FIG. 1, it can be suitably used for the angular ball bearing 30 as shown in FIG.

Further, as opposed to the front combination of the above-mentioned embodiment, the rear combination bearing device may be used. In this case, the heights h of both rings are assembled in such a relationship that the change thereof is opposite to that in the frontal combination.

Further, of the two rings 6 and 7 that form the sliding ring band 8, the ring 7 that contacts the end face side of the outer ring is not formed as an independent ring but is formed directly on the end face of the outer ring itself. It is also possible to implement it as one of the two rings.

〔The invention's effect〕

As described above, according to the present invention, two rings that are rotatably opposed to each other via a slope are driven by an actuator that is deformable in the ring rotation direction according to a temperature change, and the two rings are rotated. Since the relative rotation is exchanged for the axial displacement, there is an effect that it is possible to provide a preload compensator for a rolling bearing having a large axial rigidity.

[Brief description of drawings]

1 to 5 show an embodiment of the present invention. FIG. 1 is an assembled side view applied to a tapered roller bearing, FIG. 2 is a plan view, FIG. 3 is a side view, and FIG. 4 is an actuator. FIG. 5 is a side view thereof, FIG. 5 is a side view thereof, FIG. 6 is a plan view of another embodiment, FIG. 7 is a plan view of yet another embodiment, FIG. 8 is a side view thereof, and FIG. It is an assembly side view applied to a ball bearing. 1 is a shaft, 2 is a bearing, 3 is a housing, 5 is a preload compensator, 6.7
Is a ring, 8 is a sliding ring, 9.20 is an elastic actuator, and 10 is a slope.

Claims (4)

[Claims] 1. A preload compensating device for a rolling bearing, which is used by being interposed between a rolling bearing supporting a rotating shaft and a housing of the bearing, and having the same inclination angle on one end face of an annular shape. A sliding ring body, in which two rings, each of which has a plurality of slopes intermittently arranged in the circumferential direction, are brought into contact with each other so as to be relatively rotatable, and one end has one ring,
The other end is locked to the other ring, and is provided with at least one elastic actuator that deforms in the rotation direction of the ring according to temperature change and relatively rotates the ring in the circumferential direction. Preload compensator for rolling bearings. 2. The inclination angle β of the slope is tan β <μ (where μ
Is the coefficient of friction between both rings).
A preload compensating device for a rolling bearing according to the item. 3. The preload compensating device for a rolling bearing according to claim 1, wherein the elastic actuator comprises a ring-shaped temperature deformable member. 4. The preload compensating device for a rolling bearing according to claim 1, wherein the elastic actuator is composed of a plurality of plate-shaped temperature deforming members radially arranged between the rings.