WO2022004175A1

WO2022004175A1 - Roller bearing

Info

Publication number: WO2022004175A1
Application number: PCT/JP2021/019104
Authority: WO
Inventors: 敏和伴
Original assignee: Thk株式会社
Priority date: 2020-07-02
Filing date: 2021-05-20
Publication date: 2022-01-06
Also published as: JP7245808B2; TW202223257A; JP2022012756A

Abstract

Provided is a roller bearing capable of improving load rating and rigidity. Disclosed is a roller bearing (5) wherein: a plurality of rollers (3) are arranged between track grooves formed respectively in an inner race (1) and an outer race (2), each track groove having a V-shape in a cross-sectional view; and a spacer (4) is arranged between adjacent rollers (3). The thickness of each spacer (4) defining the interval between the adjacent rollers (3) is made thin so that the thickness is at most 20% of the roller diameter. To prevent the spacer (4) from collapsing, the diagonal dimension of the spacer (4) in a side view is set so as to be greater than the roller diameter.

Description

Roller bearing

The present invention relates to a roller bearing in which a plurality of rollers are arranged between raceway grooves having a V-shaped cross section formed in each of the inner ring and the outer ring, and spacers are arranged between adjacent rollers.

Conventionally, roller bearings are known as bearings that can support complex loads that combine radial load, thrust load, and moment load. The roller bearing includes an inner ring, an outer ring, a plurality of rollers arranged in a raceway groove having a V-shaped cross section formed on the surfaces of the inner ring and the outer ring facing each other, and a spacer arranged between adjacent rollers. Be prepared. The spacer is formed with a pocket for storing a lubricant such as grease applied to the roller. By arranging spacers between adjacent rollers, mutual contact between the rollers can be prevented and the lubricity of the rollers can be improved.

Japanese Patent Application Laid-Open No. 2003-20932

In recent years, it has been requested to further improve the rated load and rigidity of roller bearings. If there is such a request, it is handled by a total roller without using a spacer. However, if the spacer is not used, the rollers may come into mutual contact with each other, and the lubricant held by the spacer may be lost, resulting in a decrease in lubricity, and the roller bearing may be damaged at an early stage. As a measure to prevent this, the lubrication time of the lubricant is shortened or forced lubrication with oil is adopted.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a roller bearing capable of improving the rated load and rigidity even if a spacer is arranged between adjacent rollers.

In order to solve the above problems, one aspect of the present invention is a roller bearing in which a plurality of rollers are arranged between raceway grooves having a V-shaped cross section formed in each of the inner ring and the outer ring, and spacers are arranged between adjacent rollers. , The thickness (t) of the spacers that determines the distance between adjacent rollers is _{set thin to 20% or less of the roller diameter (D w} ), and in order to prevent the spacers from collapsing, a pair of the spacers in a side view. A roller bearing whose angular dimension (D) is set to be larger than the _{roller diameter (D w).}

According to the present invention, the rated load and rigidity of the roller bearing can be improved by thinning the spacer and increasing the number of rollers. If the spacer is made thinner, the spacer tends to fall between the rolling surfaces of the raceway grooves of the inner ring and the outer ring, but the diagonal dimension (D) of the spacer in the side view is the roller diameter (D _w ) (roller diameter D _w is the rolling surface). Since it is set to be larger than the distance between them), it is possible to prevent the spacer from collapsing between the rolling surfaces.

FIG. 1A is a perspective view of a roller bearing according to the first embodiment of the present invention, and FIG. 1B is a perspective view of a roller bearing according to the prior art. It is sectional drawing of the roller bearing of this embodiment. It is a perspective view of the spacer of the roller bearing of this embodiment. A detailed view of the spacer (FIG. 4 (a) is a front view, FIG. 4 (b) is a sectional view taken along line bb of FIG. 4 (a), and FIG. 4 (c) is a line cc of FIG. 4 (a). Sectional view). 5 (a) is a diagram showing the pitch circle diameter of the roller bearing of the present embodiment, and FIGS. 5 (b) and 5 (c) are enlarged views of the circulation path seen from an oblique 45 degree direction. FIG. 6A is a front view, and FIG. 6B is a sectional view taken along line bb of FIG. 6A, showing another example of the spacer of the roller bearing of the present embodiment. It is a perspective view (including a partial sectional view) of the roller bearing of the 2nd Embodiment of this invention. FIG. 7 is an enlarged view of part VII of FIG. Detailed view of the spacer of the roller bearing of the second embodiment of the present invention (FIG. 9 (a) is a front view, FIG. 9 (b) is a sectional view taken along line bb of FIG. 9 (a), FIG. 9 (c). 9 (a) is a cross-sectional view taken along the line cc of FIG. 9 (a).

Hereinafter, the roller bearing according to the embodiment of the present invention will be described with reference to the accompanying drawings. However, the roller bearing of the present invention can be embodied in various forms, and is not limited to the embodiments described in the present specification. The present embodiment is provided with the intention of allowing those skilled in the art to fully understand the invention by adequately disclosing the specification.
(First Embodiment)

FIG. 1A is a perspective view of the roller bearing 5 according to the first embodiment of the present invention. FIG. 1B is a perspective view of the roller bearing 25 of the prior art. 1 is an inner ring, 2 is an outer ring, 3 is a roller, and 4 is a spacer. In FIG. 1A, a part of the outer ring 2 is cut out in order to show the roller 3 and the spacer 4 arranged between the inner ring 1 and the outer ring 2.

In the present embodiment, the spacer 4 is made thinner than the spacer 24 of the prior art, the distance between the adjacent rollers 3 is narrowed, and the number of rollers 3 arranged between the inner ring 1 and the outer ring 2 is increased. This improves the rated load and rigidity. The thickness t (see FIG. 4B) of the spacer 4 that determines the distance between the adjacent rollers 3 is set _{to 20% or less of the roller diameter D w} , preferably 15% or less, and more preferably 10% or less. ..

As shown in FIG. 2, a raceway groove 6 having a V-shaped cross section extending in the circumferential direction and having a right-angled apex angle is formed on the outer peripheral surface of the inner ring 1. The track groove 6 includes a first rolling surface 6a and a second rolling surface 6b. On the inner peripheral surface of the outer ring 2, a raceway groove 7 having a V-shaped cross section extending in the circumferential direction and having a right-angled apex angle is formed. The track groove 7 includes a first rolling surface 7a and a second rolling surface 7b. The outer ring 2 is divided into upper and lower parts.

The raceway groove 6 of the inner ring 1 and the raceway groove 7 of the outer ring 2 face each other. The track groove 6 and the track groove 7 form a circulation path 8 having a substantially square cross section. In the circulation path 8, a plurality of rollers 3 are cross-arranged so that the axes of the adjacent rollers 3 are substantially at right angles. The roller 3 has a cylindrical shape. The roller diameter Dw is set to be slightly larger than the axial length L of the roller 3.

As shown in FIG. 1A, the roller bearing 5 of this embodiment is a cross roller bearing. The roller 3 is classified into an upward roller 3a and a downward roller 3b. The upward roller 3a revolves between the second rolling surface 6b of the inner ring 1 and the second rolling surface 7b of the outer ring 2 with the line passing through the virtual center point P1 located above as the axis. The downward roller 3b revolves between the first rolling surface 6a of the inner ring 1 and the first rolling surface 7a of the outer ring 2 with the line passing through the virtual center point P2 located below as the axis.

Individual spacers 4 are arranged between adjacent rollers 3. FIG. 3 is a perspective view of the spacer 4, and FIG. 4 is a detailed view of the spacer 4. In the following, for convenience of explanation, the configuration of the spacer 4 will be described using the direction when the spacer 4 is viewed from the traveling direction, that is, the vertical, horizontal, and front-rear directions of FIG.

In front view, the spacer 4 is formed in a substantially square shape (see FIG. 4A). An arcuate chamfer 9 is formed at the corner of the spacer 4. As shown in FIG. 3, semi-cylindrical

concave surfaces

10 and 11 for receiving the rollers 3 are formed at both ends of the spacer 4 in the front-rear direction. The extending directions of the concave surface 10 and the concave surface 11 are at right angles. The cross sections of the

concave surfaces

10 and 11 are arcuate in which the radius is slightly larger than the radius of the roller 3. The concave surfaces 10 and 11 and the roller 3 come into contact with each other at the central portion of the

concave surfaces

10 and 11. Chamfers 12 are formed on both edges of the

concave surfaces

10 and 11. An arcuate pocket 13 for storing a lubricant such as grease is formed in the central portion of the concave surface 10. A similar pocket (not shown) is also formed in the central portion of the concave surface 11. The pocket 13 of the concave surface 10 and the pocket of the concave surface 11 are communicated with each other by a through hole 14 so that the lubricant can move between them. Constrictions 23 having an arc-shaped cross section are formed on the upper surface, the left and right side surfaces, and the lower surface of the spacer 4. Lubricant is stored in the constriction 23.

As shown in FIG. 4A, the width of the spacer 4 is A in front view. The height of the spacer 4 is B. As shown in FIG. 4B, the thickness of the spacer 4 that determines the distance between the adjacent rollers 3 is t. The length of the spacer 4 in the traveling direction in the side view is C. The diagonal dimension D of the spacer 4 in the side view is represented by ^{D = √ (B 2} + C ^2).

When the spacer 4 is made thin, C becomes small, and the spacer 4 easily falls between the first rolling surface 6a of the inner ring 1 and the first rolling surface 7a of the outer ring 2. In the present embodiment, the diagonal dimension D of the spacer 4 in the side view> the roller diameter D _w is set to prevent the spacer 4 from collapsing. The roller diameter D _w is equal to the distance between the first rolling surface 6a of the inner ring 1 and the first rolling surface 7a of the outer ring 2. By setting diagonal dimension D> roller diameter D _w , even if the spacer 4 tries to tilt by a predetermined angle or more, the diagonal portion of the spacer 4 is the first rolling surface 6a of the inner ring 1 and the first rolling surface of the outer ring 2. It is caught in 7a and the spacer 4 is prevented from falling.

As described above, in the spacer 4 of the present embodiment, B and C are set so as to satisfy the following equation (1).

(Number 1)
D = √ (B ² + C ² )> D _w ... (1)

Further, as shown in FIG. 4C, in order to prevent the spacer 4 from falling between the second rolling surface 6b of the inner ring 1 and the second rolling surface 7b of the outer ring 2, A and C are used. It is set to satisfy the following equation (2).

(Number 2)
D = √ (A ² + C ² )> D _w ... (2)
If the above equations (1) and (2) are satisfied, the spacer 4 can be prevented from falling even if the spacer 4 is thinned. It should be noted that A = B or A ≠ B may be set.

As described above, the equations (1) and (2) mean that A and B are enlarged to prevent the spacer 4 from collapsing. However, if A and B are increased, the spacer 4 interferes with the

raceway grooves

6 and 7. In order to prevent interference, it is necessary to set the upper limits of A and B as follows.

FIG. 5A is a diagram showing the pitch circle diameter of the roller bearing 5. 3 is a roller, and D _pw is a pitch circle diameter. The pitch circle diameter D _pw is the diameter of a circle connecting the centers of the rollers 3 arranged in the circulation path 8. FIG. 5B is from a direction at an angle of 45 degrees (the direction of the arrow V in FIG. 5A, which is parallel to the first rolling surface 6a of the inner ring 1 and the first rolling surface 7a of the outer ring 2). It is an enlarged view of the circulation path 8 seen. When the height B of _{the spacer 4 is increased to AB max} , the spacer 4 contacts the first rolling surface 6a of the inner ring 1 at one point N1 and contacts the first rolling surface 7a of the outer ring 2 at two points N2 and N3. do. As shown in FIG. 5 (c), when viewed from an oblique direction of 45 degrees, the first rolling surface 6a of the inner ring 1 and the first rolling surface 7a of the outer ring 2 are both elliptical, so that the point M1 is used. _{AB max} , which is the distance between points M2, can be obtained from the following equation (3).

(Number 3)

Here, D _pw is the pitch circle diameter, and D _w is the roller diameter.
_{By setting A and B to less than AB max} as in the equation (4), it is possible to prevent the spacer 4 from interfering with the

raceway grooves

6 and 7.
(Number 4)

The configuration of the roller bearing 5 of this embodiment has been described above. According to the roller bearing 5 of the present embodiment, the following effects are obtained.

Since the thickness t of the spacer 4 that determines the distance between the adjacent rollers 3 is _{set thin to 20% or less of the roller diameter D w} , the rated load and rigidity of the roller bearing 5 can be improved. When the spacer 4 is made thin, the spacer 4 tends to fall between the first rolling surfaces 6a and 7a and the second rolling surfaces 6b and 7b of the inner ring 1 and the outer ring 2, but the diagonal dimension D of the spacer 4 in the side view. Can be set to be larger than the roller diameter D _{w to prevent the spacer 4 from collapsing.}

By setting the A, B, and C dimensions of the spacer 4 so that the equations (3) and (4) are satisfied, it is possible to prevent the spacer 4 from interfering with the

raceway grooves

6 and 7.

Since

concave surfaces

10 and 11 for receiving the rollers 3 are formed at both ends of the spacer 4 in the traveling direction, C can be increased even if the thickness t of the spacer 4 is reduced, and the diagonal dimension D of the spacer 4 is increased. be able to.

If the thickness t of the spacer 4 is _{set thin to 15% or less of the roller diameter D w} , the number of rollers 3 can be increased in the roller bearings 5 of many model numbers.

The spacer 4 of the present embodiment is suitable for improving the rated load and rigidity of the cross roller bearing in which the roller 3 is classified into the upward roller 3a and the downward roller 3b.

The spacer 4 is made of a molded body obtained by mixing a resin such as nylon with a reinforcing fiber such as glass fiber. By doing so, sufficient strength can be secured even if the spacer 4 is made thin.

As shown in FIG. 4B, in the spacer 4 of the first embodiment, the thickness a between the central portion of the lower end edge of the concave surface 10 and the central portion of the lower end edge of the concave surface 11 and the upper end edge of the concave surface 10 are formed. The thickness b between the central portion and the central portion of the upper end edge of the concave surface 11 is set to be substantially the same (a = b). When the thickness t of the spacer 4 becomes thin and the number of rollers 3 increases, the axes of the adjacent rollers 3 become close to parallel in a plan view. Therefore, even if a = b is set, the roller 3 moves without any problem. By setting a = b, it is not necessary to create the spacer 4 each time the pitch circle diameter is different, and the spacer 4 can be easily formed.
(Other examples of spacers)

FIG. 6 shows another example of the spacer 4. In this example, the thickness a between the central portion of the lower end edge of the concave surface 10 and the central portion of the lower end edge of the concave surface 11 and the thickness between the central portion of the upper end edge of the concave surface 10 and the central portion of the upper end edge of the concave surface 11. b is set to a <b. The concave surface 10 and the concave surface 11 are inclined by an angle θ. As a result, as shown in FIG. 1, the axis of the upward roller 3a tends to face the virtual center point P1, and the axis of the downward roller 3b tends to point to the virtual center point P2. Other configurations of the spacer 4 are the same as the spacer 4 shown in FIG.

In the case of this example, as shown in FIG. 6B, the thickness t of the spacer 4 that determines the distance between the adjacent rollers 3 is the thickness between the central portion of the concave surface 10 and the central portion of the concave surface 11. .. The diagonal dimension D is the shorter diagonal dimension of the two diagonal dimensions.
(Second embodiment)

7 and 8 are perspective views (including a partial cross-sectional view) of the roller bearing 15 according to the second embodiment of the present invention. The roller bearing 5 of the first embodiment is a cross roller bearing, while the roller bearing 15 of the second embodiment is a parallel roller bearing. In the roller bearing 15 of the second embodiment, the axes of the adjacent rollers 3 are arranged in parallel so as to be substantially parallel to each other. The roller 3 is classified into an upward roller 3a and a downward roller 3b.

As shown in FIG. 8, two upper and lower rolling

grooves

18 and 19 are formed on the outer peripheral surface of the inner ring 16. Two upper and lower rolling

grooves

20 and 21 facing the rolling

grooves

18 and 19 are formed on the inner peripheral surface of the outer ring 17. The downward rollers 3b are arranged in parallel between the upper rolling groove 18 and the upper rolling groove 20. The upward rollers 3a are arranged in parallel between the lower rolling groove 19 and the lower rolling groove 21. As shown in FIG. 7, the upward roller 3a revolves between the rolling surface 19a of the inner ring 16 and the rolling surface 21a of the outer ring 17 with the line passing through the virtual center point P1 located above as the axis. The downward roller 3b revolves around the rolling surface 18a of the inner ring 16 and the rolling surface 20a of the outer ring 17 with the line passing through the virtual center point P2 located below as the axis.

FIG. 9 shows the spacer 22 used in the roller bearing 15 of the second embodiment. The structure of the spacer 22 is the same as that of the spacer 4 of the first embodiment, except that the

concave surfaces

10 and 11 are formed in parallel in the extending direction. As shown in FIGS. 9 (b) and 9 (c), the thickness t of the spacer 22 that determines the distance between adjacent rollers 3 is 20% or less, preferably 15% or less, and more preferably 10% or less of the diameter of the rollers 3. It is set thinly to. Further, in order to prevent the spacer 22 from collapsing, as shown in FIG. 9C, the diagonal dimension D of the spacer 22 in the side view is set to be larger than the roller diameter Dw. By doing so, the spacer 22 is prevented from falling between the rolling surface 19a of the inner ring 16 and the rolling surface 21a of the outer ring 17 and between the rolling surface 18a of the inner ring 16 and the rolling surface 20a of the outer ring 17. can do. Also in the spacer 22 of the second embodiment, the concave surface 10 and the concave surface 11 may be tilted symmetrically by θ.

The present invention is not limited to being embodied in the above embodiment, and can be embodied in other embodiments without changing the gist of the present invention.

For example, a tapered roller can be used as the roller instead of the cylindrical roller. The tapered rollers may be cross-arranged so that the axes of adjacent tapered rollers are substantially perpendicular to each other, or may be arranged in parallel so that the axes of adjacent tapered rollers are substantially parallel to each other. The diameter of the central portion in the axial direction of the tapered roller is regarded as the diameter of the tapered roller, and the thickness t of the central portion of the spacer and the diagonal dimension D of the central portion of the spacer may be set in the same manner as in the spacer of the above embodiment.

This specification is based on Japanese Patent Application No. 2020-114816 filed on July 2, 2020. All this content is included here.

1 ... Inner ring 2 ... Outer ring 3 ... Roller 4 ... Spacer 5 ... Roller bearing 6 ... Inner ring raceway groove 7 ... Outer ring raceway groove 10 ... Spacer one concave surface 11 ... Spacer other concave surface 15 ... Roller bearing 16 ... Inner ring 17 ...

Outer ring

18, 19 ... Inner

ring rolling groove

20, 21 ... Outer ring rolling groove 22 ... Spacer D ... Spacer diagonal dimension D _w ... Roller diameter

Claims

In a roller bearing in which a plurality of rollers are arranged between raceway grooves having a V-shaped cross section formed in each of the inner ring and the outer ring, and spacers are arranged between adjacent rollers.
The thickness (t) of the spacer that determines the distance between adjacent rollers is set thinly to 20% or less of the roller diameter (D w).
A roller bearing in which the diagonal dimension (D) of the spacer in a side view is set to be larger than the roller diameter (D w) in order to prevent the spacer from tipping over.
When the width of the spacer in the front view is A, the height of the spacer in the front view is B, and the length of the spacer in the traveling direction in the side view is C, the following equations (3) and (4) are as follows. The roller bearing according to claim 1, wherein the roller bearing is satisfied.

Here, D pw is the pitch circle diameter of the roller bearing, and D w is the roller diameter.
The roller bearing according to claim 1 or 2, wherein concave surfaces for receiving the rollers are formed at both ends of the spacer in the traveling direction.
The roller bearing according to any one of claims 1 to 3, wherein the thickness (t) of the spacer is set as thin as 15% or less of the roller diameter (D w).
The roller bearing according to any one of claims 1 to 4, wherein the plurality of rollers are alternately arranged so that the axes of adjacent rollers are perpendicular to each other between the raceway grooves.
The roller bearing according to any one of claims 1 to 5, wherein the spacer is made of a molded body in which reinforcing fibers are mixed with a resin.