JP2023170681A - Double row angular ball bearing - Google Patents

Abstract

To provide a double row angular ball bearing which is excellent in axial loading capability and moment loading capability, and capable of sufficiently securing a space for a cage to be arranged therein or good in assemblability (ball inserting property).SOLUTION: A double row angular ball bearing 1' includes an outer ring 2' used for a pump and having outer ring raceway surfaces 2a' on the inner periphery, an inner ring 3 having inner ring raceway surfaces 3a on the outer periphery, and a plurality of rolling elements 4 arranged between each outer ring raceway surface 2a' and each inner ring raceway surface 3a, the outer ring raceway surfaces 2a' plurally neighboring each other in the axial direction, the inner ring raceway surfaces 3a plurally neighboring each other in the axial direction, the inner ring 3 being split in the axial direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a double-row angular contact ball bearing, and more particularly to a double-row angular contact ball bearing used in a pump (for example, a hydrogen circulation pump).

Various bearings are used in devices having a rotation mechanism depending on the purpose. As common rolling bearings, for example, deep groove ball bearings, angular contact ball bearings, tapered roller bearings, etc. are known. Angular contact ball bearings can receive radial loads as well as unidirectional axial loads. In angular contact ball bearings, the balls (rolling elements) and the inner and outer rings have a contact angle, and the larger the contact angle, the greater the load capacity that can receive an axial load.

Double-row angular contact ball bearings are known as bearings that can bear axial loads in both directions and also have the ability to bear moment loads. As a double-row angular contact ball bearing, for example, a structure in which single-row angular contact ball bearings are assembled back-to-back and the inner and outer rings are each integrated is known. As this double-row angular contact ball bearing, for example, a structure in which the shoulder height of the side shoulder portion receiving the load of the bearing ring is increased is known (Patent Document 1).

Conventionally, double-row angular contact ball bearings have been used, for example, as rolling bearings for pumps, compressors, and the like. For example, Patent Document 2 discloses that a double-row angular ball bearing is used in a roots-type hydrogen circulation pump for a fuel cell. Specifically, in the pump described above, two rotating shafts arranged to protrude into the rotor chamber from the gear chamber side are each rotatably supported by double row angular ball bearings. Further, a driving rotor or a driven rotor is attached to one side of these rotating shafts, and a driving gear or a driven gear is attached to the other side.

Japanese Patent Application Publication No. 8-270644 JP2021-127736A

By the way, in the case of a fluid machine (for example, a hydrogen circulation pump) that includes a drive gear and a drive rotor connected to a motor, a driven gear that meshes with the drive gear, and a driven rotor that meshes with the drive rotor, as in Patent Document 2, for example, A load is applied between the drive gear and the driven gear, and between the drive rotor and the driven rotor. Therefore, it is thought that bearings such as those used here are particularly required to have axial load capacity and moment load capacity (moment resistance).

In double-row angular contact ball bearings, if an excessive axial load is applied and the groove shoulder height is low, the balls may ride on the bearings and peeling may occur from that area. Therefore, the higher the height of the groove shoulder is, the more advantageous it is to prevent the vehicle from running over the vehicle. However, if the groove shoulder height is too high, it becomes difficult to secure a space for arranging the cage. Furthermore, it is thought that it becomes difficult to insert the balls between the bearing rings when assembling the bearing. For example, Patent Document 1 describes increasing the groove shoulder height of the inner ring and the outer ring, but does not provide a suitable design for the above-mentioned problems.

The present invention has been made in view of these circumstances, and has excellent axial load capacity and moment load capacity, as well as the ability to secure sufficient space for arranging the cage, and ease of assembly (insertion of balls). The purpose of the present invention is to provide a double-row angular contact ball bearing with good performance.

The double-row angular contact ball bearing of the present invention is used in a hydrogen circulation pump, and includes an outer ring having an outer ring raceway surface on the inner periphery, an inner ring having an inner ring raceway surface on the outer periphery, and a plurality of the above outer ring raceway surfaces and the above inner ring raceway surfaces. , a plurality of rolling elements disposed between the outer ring raceway surface and the inner ring raceway surface, and the double row angular contact ball bearing has at least one raceway ring of the outer ring and the inner ring divided in the axial direction. It is characterized by

The above-mentioned double-row angular contact ball bearing is a separate type raceway in which one of the outer ring and the inner ring is divided in the axial direction, and the other raceway is an integrated raceway having a plurality of raceway surfaces. It is characterized by being a ring.

The double-row angular contact ball bearing is characterized in that it has two rows in which the outer ring raceway surface and the inner ring raceway surface face each other, and the directions of the contact angles of the rolling elements in each row are different from each other. Furthermore, it is characterized in that the arrangement is a back-to-back arrangement.

A shoulder is formed on the inner periphery of the outer ring and the outer periphery of the inner ring, the height hD of the shoulder of the outer ring satisfies the following formula (1), and the height hd of the shoulder of the inner ring is It is characterized by satisfying the following formula (2).
0.15×(Dα-dp)≦hD≦0.35×(Dα-dp)...(1)
0.15×(dp-dα)≦hd≦0.35×(dp-dα)...(2)
Dα: Diameter of the contact point of the outer ring with the rolling element dα: Diameter of the contact point of the inner ring with the rolling element dp: Pitch diameter of the rolling element

The diameter Db of the rolling element and the axial width Wb of the double-row angular contact ball bearing satisfy the following equation (3).
1.1≦Wb/(Db×2)≦1.7...(3)

It is characterized in that the filling factor γ of the rolling elements arranged in one row of the raceway, expressed by the following formula (4), is 0.65 to 0.90.
γ=(Db×Z)/(dp×π)...(4)
Db: Diameter of the above rolling element Z: Number of the above rolling elements dp: Pitch diameter of the above rolling element

The double-row angular contact ball bearing has one end connected to the rotor that is mated to the mating rotor, and rotatably supports the rotating shaft to which the mating gear is connected to the other end. It is characterized by

The double-row angular contact ball bearing of the present invention is used in a hydrogen circulation pump, and includes an outer ring having an outer ring raceway surface on the inner periphery, an inner ring having an inner ring raceway surface on the outer periphery, and a plurality of the above outer ring raceway surfaces and the above inner ring raceway surfaces. , a plurality of rolling elements disposed between the outer ring raceway surface and the inner ring raceway surface, and the double row angular contact ball bearing has shoulders formed on an inner periphery of the outer ring and an outer periphery of the inner ring, respectively. , the height hD of the shoulder portion of the outer ring satisfies the following formula (5), and the height hd of the shoulder portion of the inner ring satisfies the following formula (6).
0.15×(Dα-dp)≦hD≦0.35×(Dα-dp) (5)
0.15×(dp-dα)≦hd≦0.35×(dp-dα)...(6)
Dα: diameter of the contact point of the outer ring with the rolling element dα: diameter of the contact point of the inner ring with the rolling element dp: pitch diameter of the rolling element

The double-row angular contact ball bearing of the present invention is used in a hydrogen circulation pump, and has a plurality of outer ring raceway surfaces and inner ring raceway surfaces, and at least one of the outer ring and the inner ring is divided in the axial direction, that is, the inner ring or Since the outer ring is separated into left and right sides, when assembling the bearing, the rolling elements can be assembled from the side of the bearing together with the divided bearing rings. As a result, more rolling elements can be arranged, and the rated load becomes larger. This provides excellent axial load capacity and moment load capacity, as well as excellent ease of assembly.

A double-row angular contact ball bearing is a split-type bearing ring in which either the outer ring or the inner ring is divided in the axial direction, and the other ring is an integrated bearing ring with multiple raceway surfaces. Therefore, it is easier to assemble than when both the inner ring and outer ring are separate bearing rings (when a single row angular contact ball bearing is combined). Furthermore, since the width dimension of the bearing in the axial direction can be made smaller than when a single row angular contact ball bearing is combined, it is easier to save space.

Double-row angular contact ball bearings have two rows of raceways in which the outer ring raceway surface and the inner ring raceway surface face each other, and the contact angles of the rolling elements in each row differ from each other, so they cannot receive bidirectional axial loads. Can be done. Furthermore, since the arrangement is a back-to-back arrangement, the distance between the points of action is greater than in a front-to-front arrangement (DF), and the moment load capacity can be further improved.

Shoulders are formed on the inner circumference of the outer ring and the outer circumference of the inner ring, respectively, and the height hD of the shoulder of the outer ring satisfies the above formula (1), and the height hd of the shoulder of the inner ring satisfies the above formula (2). This makes it difficult for the shoulders of the rolling elements to ride on each other, and makes it easier to secure a sufficient space for arranging the cage.

Since the diameter Db of the rolling element and the axial width Wb of the double-row angular contact ball bearing satisfy the relationship of the above equation (3), the diameter Db of the rolling element can be maintained, and the strength and rated load of the shoulder can be ensured. Moreover, the axial width Wb can be suppressed, contributing to compactness.

Since the filling factor γ of the rolling elements arranged in one row of the raceway, expressed by the above formula (4), is 0.65 to 0.90, both the inner ring and the outer ring are better than non-separable double-row angular contact ball bearings. The rated load can be increased. Furthermore, a sufficient space for arranging the cage can be secured, and the column width between the pockets of the cage (in the circumferential direction) does not become too small, so that a decrease in the strength of the cage can be suppressed.

The double-row angular contact ball bearing of the present invention is used in a hydrogen circulation pump, and has multiple rows of raceways in which an outer ring raceway surface and an inner ring raceway surface face each other, and shoulders are formed on the inner periphery of the outer ring and the outer periphery of the inner ring. , the shoulder height hD of the outer ring satisfies the above formula (5), and the height hd of the inner ring shoulder satisfies the above formula (6), so it has excellent axial load capacity and moment load capacity, and has excellent retention. Enough space can be secured to place the utensils.

FIG. 1 is a longitudinal cross-sectional view of a first embodiment of a double-row angular contact ball bearing of the present invention. FIG. 2 is a longitudinal cross-sectional view of a second embodiment of the double-row angular contact ball bearing of the present invention. 3 is a partial cross-sectional view of the double-row angular contact ball bearing shown in FIG. 2. FIG. FIG. 2 is a sectional view of a hydrogen circulation pump using the double-row angular contact ball bearing of the present invention.

The double-row angular contact ball bearing of the present invention has a plurality of outer ring raceway surfaces and inner ring raceway surfaces, and at least one of the outer ring and inner ring is divided in the axial direction, and there are three types depending on how the bearing rings are divided. There is. In other words, there are two types: one in which multiple single row angular contact ball bearings are combined in parallel (see Figure 1), one in which the outer ring is integrated and the inner ring is separated (see Figure 2), and one in which the inner ring is integrated and the outer ring is separated. be. A detailed description will be given below with reference to the drawings.

(First embodiment)
A first embodiment of the double-row angular contact ball bearing of the present invention will be described based on FIG. 1. FIG. 1 is a longitudinal sectional view of the bearing. As shown in FIG. 1, the double-row angular contact ball bearing 1 includes an outer ring 2 having an outer ring raceway surface 2a on the inner periphery, an inner ring 3 having an inner ring raceway surface 3a on the outer periphery, and an outer ring raceway surface 2a and an inner ring raceway surface 3a. and a plurality of rolling elements 4 disposed between them. Here, the outer ring raceway surface 2a and the inner ring raceway surface 3a are each a concave groove extending in the circumferential direction. The outer ring 2 has a plurality of axially adjacent outer ring raceway surfaces 2a (two rows in FIG. 1), and the inner ring 3 has a plurality of axially adjacent inner ring raceway surfaces 3a (two rows in FIG. 1). are doing. The outer ring 2 and the inner ring 3 are each annular, and the inner ring 3 is arranged concentrically with the outer ring 2 so as to be relatively rotatable.

In this embodiment, both the outer ring 2 and the inner ring 3 are separable bearing rings divided into two in the axial direction, and each separated bearing ring has one row of raceway surfaces. The double-row angular contact ball bearing 1 has two rows of raceways in which an outer ring raceway surface 2a and an inner ring raceway surface 3a are formed facing each other. A plurality of rolling elements 4 are arranged on each track, and the rolling elements 4 are rotatably held by a retainer 5. The radius of curvature of each raceway surface 2a, 3a is dimensioned to be slightly larger than the radius of curvature of the rolling element 4.

The double-row angular contact ball bearing 1 of the first embodiment is configured by back-to-back combination of single-row angular contact ball bearings. Each angular contact ball bearing has an inner ring, an outer ring, and a rolling element that are in contact with each other at a predetermined angle α (contact angle) with respect to the radial center line, and can carry a radial load and an axial load in one direction. . In FIG. 1, since the directions of the contact angle α of the rolling elements 4 on each raceway are different from each other, it is possible to receive bidirectional axial loads. In the present invention, the contact angle α is not particularly limited, but is preferably 20 to 40°, more preferably 25 to 35°.

Further, the outer ring 2 has shoulder portions 2b on the load side where the contact portion with the rolling elements 4 is located on the inner periphery. The shoulder portion 2b is an inner shoulder portion of the double-row angular contact ball bearing 1, and the shoulder portion 2c is an outer shoulder portion. In FIG. 1, the shoulder height of the shoulder portion 2c is smaller than that of the shoulder portion 2b. Moreover, the inner ring 3 has shoulders on both sides in the axial direction on both sides of each inner ring raceway surface 3a on the outer periphery. In the double-row angular contact ball bearing 1, the inner ring 3 has an inner shoulder 3b and an outer shoulder 3c. The shoulder heights of the shoulder portion 3b and the shoulder portion 3c are the same.

In the double-row angular contact ball bearing 1, the number of outer ring raceway surfaces that the outer ring has on the inner periphery may be plural, and may be three or more rows. Further, the inner ring raceway surface of the inner ring may also be arranged in three or more rows. Note that the number of outer ring raceway surfaces and the number of inner ring raceway surfaces is the same. For example, three rows of single row angular contact ball bearings may be combined in parallel in the axial direction.

Since the double-row angular contact ball bearing 1 has the above-described configuration, the rolling elements 4 can be assembled from the side together with the divided raceway rings (outer ring 2 and inner ring 3 in FIG. 1) when assembling the bearing. As a result, the number of rolling elements 4 arranged on the raceway can be increased, and the rated load can be increased.

(Second embodiment)
A second embodiment of the double-row angular contact ball bearing of the present invention will be described based on FIG. 2. Note that the same components as those in the first embodiment described using FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 2, in the double-row angular contact ball bearing 1', the inner ring 3 is a separable ring that is divided into two in the axial direction, and each separated ring has a single row on the raceway surface. has. The outer ring 2' is a non-separable (integrated) bearing ring, and is one bearing ring that is not divided in the axial direction. Further, the outer ring 2' has two rows of raceway surfaces 2a' on the inner periphery, and a shoulder portion 2b' between these raceway surfaces.

In a configuration having a separable bearing ring and a non-separable bearing ring as shown in the second embodiment, compared to a configuration in which both the inner ring and the outer ring are separable as shown in the first embodiment, Excellent ease of assembly. Furthermore, since the non-separable bearing ring has a small width dimension, space can be saved.

In the double-row angular contact ball bearing of the present invention, the arrangement of the raceways is not limited to a back-to-back arrangement, but may be a front-to-face arrangement if the outer ring is separated and the inner ring is integrated.

Next, with reference to FIG. 3, the dimensional relationship of each member in the double-row angular contact ball bearing will be explained. FIG. 3 is a partial cross-sectional view of the double-row angular contact ball bearing of the second embodiment shown in FIG. Note that the dimensional relationships described below can also be applied to other embodiments (such as the first embodiment).

In the double-row angular contact ball bearing 1', the height (shoulder height) hD of the shoulder portion 2b' of the outer ring 2' preferably satisfies the following formula (1).
0.15×(Dα-dp)≦hD≦0.35×(Dα-dp)...(1)
Dα: Diameter of contact point of outer ring 2' with rolling element 4 dp: Pitch diameter of rolling element 4

Here, the shoulder height hD of the outer ring 2' means the height difference between the shoulder 2b' of the outer ring 2' and the deepest part of the outer ring raceway surface 2a'. Note that the inner shoulder section provided between the two rows of outer ring raceway surfaces 2a' and 2a' of the outer ring 2' and the outer shoulder section provided on the axially outer side of the two rows of outer ring raceway surfaces 2a' and 2a'. When the difference in height is different between the shoulders on the higher side, the shoulder height hD means the difference in height between the shoulders on the higher side. Here, if the height difference is generally different between the inner shoulder and the outer shoulder, the shoulder on the load side that receives the load is often higher. Further, the contact point diameter Dα means the diameter of a circle formed by the contact point between the outer ring 2' and the rolling elements 4. The pitch diameter dp means the diameter of a circle drawn by the center of the rolling element 4 when the rolling element 4 rotates on the orbit.

When the shoulder height hD of the outer ring 2' is 0.15 times or more the value of the difference between the contact point diameter Dα and the pitch diameter dp (Dα - dp), rolling elements are less likely to ride on the shoulder, and the axial load is reduced. It becomes easier to stably receive load and moment loads. Furthermore, if the shoulder height hD of the outer ring 2' is 0.35 times or less the value of (Dα-dp) above, it becomes easier to secure a sufficient space for arranging the cage. As a result, there is no need to make the cage thinner, making it easier to ensure the strength of the cage. Note that the shoulder height hD is more preferably 0.20 times or more and 0.30 times or less of the above value (Dα-dp).

Further, in the double-row angular contact ball bearing 1', the height (shoulder height) hd of the shoulder portion 3b of the inner ring 3 preferably satisfies the following formula (2).
0.15×(dp-dα)≦hd≦0.35×(dp-dα)...(2)
dα: Diameter of contact point of inner ring 3 with rolling element 4 dp: Pitch diameter of rolling element 4

Here, the shoulder height hd of the inner ring 3 is determined by the shoulder portion 3c of the inner ring 3 (in this embodiment, the shoulder portion 3b and the shoulder portion 3c may be the shoulder portion 3b since the shoulder heights are the same) and the inner ring raceway surface. It means the difference in height from the deepest part of 3a. Inner ring 3 has two rows of inner ring raceway surfaces 3a, an inner shoulder 3b provided between the two rows of inner ring raceway surfaces 3a, and an outer shoulder 3c provided on the axially outer side of the two rows of inner ring raceway surfaces 3a, 3a. When the difference in height is different between the two, the shoulder height hd means the difference in height of the shoulder on the load side that receives the load. As described above, when the difference in height between the inner shoulder and the outer shoulder is generally different, the shoulder on the load side that receives the load is often higher. Further, the contact point diameter dα means the diameter of a circle formed by the contact point between the inner ring 3 and the rolling elements 4.

When the shoulder height hd of the inner ring 3 is 0.15 times or more the value of the difference between the contact point diameter dα and the pitch diameter dp (dp−dα), the rolling elements are less likely to ride on the shoulder. Further, if the shoulder height hd of the inner ring 3 is 0.35 times or less the value of the above-mentioned difference (dp-dα), it becomes easier to secure a sufficient space for arranging the cage. Note that the shoulder height hd is more preferably 0.20 times or more and 0.30 times or less of the above value (dp-dα).

The above formulas (1) and (2) were determined by various studies by changing the contact angle α and the diameter Db of the rolling elements 4, etc., and found that the rolling elements are less likely to ride on the shoulder and that a wide space for arranging the cage is required. It was discovered as a conditional expression that can be ensured. In general, the shoulder heights hD and hd may be set as a magnification of the diameter Db of the rolling element, but by using the above formulas (1) and (2), it is possible to prevent the rolling element 4 from riding on the shoulder, This makes it easier to evaluate from both the viewpoints of securing internal space.

Furthermore, in the double-row angular contact ball bearing 1', it is preferable that the diameter Db of the rolling elements 4 and the bearing width (axial width of the bearing) Wb satisfy the relationship expressed by the following formula (3).
1.1≦Wb/(Db×2)≦1.7...(3)

Here, the diameter Db of the rolling element 4 means the nominal dimension of the diameter of the rolling element. The bearing width Wb means the axial length of the bearing ring (the longer one if the inner ring 3 and the outer ring 2' are different).

When Wb/(Db×2) is 1.1 or more, there is no need to reduce the diameter Db of the rolling element 4, and the strength and rated load of the shoulder portion can be easily ensured. Moreover, when Wb/(Db×2) is 1.7 or less, compactness is excellent. Note that Wb/(Db×2) is more preferably 1.4 or more and 1.7 or less.

Further, in the angular contact ball bearing 1', it is preferable that the filling factor γ of the rolling elements 4 arranged in one row of the raceway is 0.65 to 0.90. The filling rate γ is expressed by the following formula (4).
γ=(Db×Z)/(dp×π)...(4)

When the filling factor γ is 0.65 or more, it is easier to increase the rated load than a double-row angular contact ball bearing in which both the inner and outer rings are non-separable. Furthermore, when the filling factor is 0.90 or less, the column width between the pockets of the cage does not become too small, making it easier to ensure the strength of the cage. Note that the filling factor γ is more preferably 0.70 to 0.90, and even more preferably 0.80 to 0.90.

In the double-row angular contact ball bearing of the present invention, it is preferable that at least one of the above formulas (1) to (4) is satisfied, and it is particularly preferable that all of them are satisfied.

(Third embodiment)
A third embodiment of the double-row angular contact ball bearing of the present invention will be described (not shown). The double-row angular contact ball bearing of the present invention does not need to have a structure in which at least one raceway ring of the outer ring and the inner ring is divided in the axial direction as described in the first embodiment and the second embodiment. Specifically, a double-row angular contact ball bearing in which both the outer ring and the inner ring are non-separable bearing rings may be used. Note that detailed descriptions of the same configurations as those in the first embodiment and the second embodiment will be omitted.

In the double-row angular contact ball bearing of the third embodiment, both the outer ring and the inner ring are non-separable bearing rings. In the double-row angular contact ball bearing, shoulders are formed on the inner circumference of the outer ring and the outer circumference of the inner ring, and the height hD of the shoulder portion of the outer ring satisfies the following formula (5), and the height hD of the shoulder portion of the inner ring satisfies the following formula (5). satisfies the following formula (6).
0.15×(Dα-dp)≦hD≦0.35×(Dα-dp) (5)
0.15×(dp-dα)≦hd≦0.35×(dp-dα)...(6)

When a double-row angular contact ball bearing has both the outer ring and the inner ring as non-separable raceway rings, from the viewpoint of ball insertion, the height hD of the shoulder of the outer ring satisfies the following formula (7) and the height of the inner ring It is more preferable that the height hd of the shoulder portion satisfies the following formula (8).
0.15×(Dα-dp)≦hD≦0.31×(Dα-dp) (7)
0.15×(dp-dα)≦hd≦0.31×(dp-dα)...(8)

As a result, the double-row angular contact ball bearing of the third embodiment is less likely to cause the shoulders of the rolling elements to run over, has excellent axial load capacity and moment load capacity, and can secure a sufficient space for arranging the cage.

The double row angular contact ball bearing of the present invention is used in a pump. As an example of a configuration applied to a hydrogen circulation pump as a pump, FIG. 4 shows a cross-sectional view of a hydrogen circulation pump. The hydrogen circulation pump 11 includes a motor housing 12, a pump housing 13, rotating shafts 14, 15, a motor stator 16, a motor rotor 17, gears 18, 19, rotors 20, 21, rolling bearings 22, 23, 24, 25, 26, and 27. Here, the rolling bearings 25 and 27 are double-row angular contact ball bearings of the present invention, and the rolling bearings 22, 23, 24, and 26 are deep groove ball bearings.

Motor housing 12 is attached to pump housing 13. One end of the rotating shaft 14 is disposed within the motor housing 12, and the other end of the rotating shaft 14 is disposed within the pump housing 13. One end and the other end of the rotating shaft 14 are rotatably supported by a rolling bearing 22 disposed within the motor housing 12 and a rolling bearing 23 disposed within the pump housing 13, respectively. Further, the rotating shaft 14 is rotatably supported between one end and the other end by a rolling bearing 24 and a rolling bearing 25 arranged within the pump housing 13.

The rotating shaft 15 is arranged within the pump housing 13. One end of the rotating shaft 15 is rotatably supported by a rolling bearing 26 disposed within the pump housing 13. The rotating shaft 15 is rotatably supported by a rolling bearing 27 disposed within the pump housing 13 at a position remote from one end.

Motor stator 16 is arranged within motor housing 12 . Motor rotor 17 is attached to rotating shaft 14 so as to face motor stator 16 . Rotating shaft 14 is rotated by motor stator 16 and motor rotor 17 . A gear 18 and a gear 19 are attached to the rotating shaft 14 and the rotating shaft 15, respectively. The rotation of the rotation shaft 14 is transmitted to the rotation shaft 15 by the gear 18 and the gear 19 . Note that the gear 18 is located between the rolling bearing 24 and the rolling bearing 25, and the gear 19 is located between the rolling bearing 26 and the rolling bearing 27.

A pump chamber 13a is formed within the pump housing 13. A rotor 20 and a rotor 21 are arranged within the pump chamber 13a. Rotor 20 and rotor 21 are attached to rotating shaft 14 and rotating shaft 15, respectively. As the rotor 20 rotates as the rotating shaft 14 rotates, and the rotor 21 rotates as the rotating shaft 15 rotates, hydrogen is sucked into the pump chamber 13a and hydrogen is discharged from the pump chamber 13a. Ru.

The rolling bearings 25 and 27 according to the present invention have one end connected to the rotors 20 and 21 to be fitted with the mating rotor, and gears 18 and 19 fitted to the mating gear to the other end. The rotary shafts 14 and 15 are rotatably supported, and axial loads and moment loads are likely to be applied thereto. In the configuration of FIG. 4, in particular, the rolling bearing 27 that supports the rotating shaft 15 connected to the gear 19, which is a driven gear, and the rotor 21, which is a driven rotor, has a free end on the rotor 21 side of the rotating shaft 15, and has one side. It is thought that the load is more likely to be applied because of the support structure. In this configuration, it is believed that by employing the double-row angular contact ball bearing of the present invention, the rotating shaft of the hydrogen circulation pump can be rotated stably without shaft wobbling.

Note that the double-row angular contact ball bearing of the present invention can be used not only for hydrogen circulation pumps but also for other pumps.

The present invention will be explained in more detail with reference to examples, but the present invention is not limited in any way by these examples.

The following study was conducted on five types of bearings (Example A) having a separate inner ring and an integrated outer ring and having different contact angles.

<Consideration of shoulder height hd, hD>
The shoulder height hD is 0.15 to 0.35 times the difference (Dα-dp) between the contact point diameter Dα between the rolling element and the outer ring and the pitch diameter dp of the rolling element (specifically, 0.15 times, 0.17 times, 0.30 times, 0.32 times, 0.35 times), the shoulder height hd is the difference between the pitch diameter dp of the rolling element and the contact point diameter dα between the rolling element and the inner ring. (dp-dα) was 0.15 times to 0.35 times (specifically, 0.15 times, 0.17 times, 0.30 times, 0.32 times, 0.35 times). It was found that in Example A, the rolling elements were less likely to ride on the shoulders, and it was easy to ensure sufficient space for arranging the retainer.

The following study was conducted on five types of bearings with a separable inner ring and an integrated outer ring (Example B), and three types of double-row angular contact ball bearings with non-separable inner and outer rings (reference examples).

<Examination of Wb/(Db×2)>
Wb/(Db×2) was calculated for Example B and Reference Example. As a result, Wb/(Db×2) of Example B was 1.407, 1.575, 1.599, 1.599, and 1.642, respectively. Further, Wb/(Db×2) of the reference examples were 1.167, 1.293, and 1.501, respectively.

<Study of filling factor γ of rolling elements>
Next, the filling factor γ was calculated for Example B and Reference Example described above. As a result, the filling factors γ of Example B were 0.81, 0.82, 0.83, 0.84, and 0.85, respectively. On the other hand, the filling factors γ of the reference examples were 0.53, 0.57, and 0.60, respectively.

The double-row angular contact ball bearing of the present invention has excellent axial load capacity and moment load capacity, and also has sufficient space for arranging a retainer or is easy to assemble, so it can be used for pumps, especially Suitable for hydrogen circulation pumps.

1, 1' Double row angular contact ball bearing 2, 2' Outer ring 2a, 2a' Outer ring raceway surface 2b, 2c Shoulder part 3 Inner ring 3a Inner ring raceway surface 3b, 3c Shoulder part 4 Rolling element 5 Cage 11 Hydrogen circulation pump 12 Motor housing 13 Pump housing 14, 15 Rotating shaft 16 Motor stator 17 Motor rotor 18, 19 Gear 20, 21 Rotor 22, 23, 24, 25, 26, 27 Rolling bearing

Claims (9)

Used in a hydrogen circulation pump, comprising an outer ring having an outer ring raceway surface on the inner periphery, an inner ring having an inner ring raceway surface on the outer periphery, a plurality of the outer ring raceway surfaces and the inner ring raceway surfaces, the outer ring raceway surface and the inner ring raceway surface. A double row angular contact ball bearing comprising a plurality of rolling elements disposed between the
The double-row angular contact ball bearing is characterized in that at least one raceway of the outer ring and the inner ring is divided in the axial direction. The double-row angular contact ball bearing is a separate type raceway in which one of the outer ring and the inner ring is divided in the axial direction, and the other raceway is an integrated raceway having a plurality of raceway surfaces. The double-row angular contact ball bearing according to claim 1, wherein the double-row angular contact ball bearing is a ring. The double-row angular contact ball bearing has two rows in which the outer ring raceway surface and the inner ring raceway surface face each other, and the contact angle directions of the rolling elements in each row are different from each other. The double row angular contact ball bearing according to claim 2. 4. The double-row angular contact ball bearing according to claim 3, wherein the arrangement is a back-to-back arrangement. Shoulders are formed on the inner periphery of the outer ring and the outer periphery of the inner ring, the height hD of the shoulder portion of the outer ring satisfies the following formula (1), and the height hd of the shoulder portion of the inner ring is The double-row angular contact ball bearing according to claim 1 or 2, characterized in that the following formula (2) is satisfied.
0.15×(Dα-dp)≦hD≦0.35×(Dα-dp)...(1)
0.15×(dp-dα)≦hd≦0.35×(dp-dα)...(2)
Dα: diameter of the contact point of the outer ring with the rolling element dα: diameter of the contact point of the inner ring with the rolling element dp: pitch diameter of the rolling element 3. The double-row angular ball bearing according to claim 1, wherein a diameter Db of the rolling element and an axial width Wb of the double-row angular ball bearing satisfy the following equation (3).
1.1≦Wb/(Db×2)≦1.7...(3) The double row according to claim 1 or 2, characterized in that the filling factor γ of the rolling elements arranged in one row of the raceway, expressed by the following formula (4), is 0.65 to 0.90. Angular contact ball bearing.
γ=(Db×Z)/(dp×π)...(4)
Db: Diameter of the rolling element Z: Number of the rolling elements dp: Pitch diameter of the rolling element The double-row angular contact ball bearing has one end connected to a rotor to be fitted with a mating rotor, and rotatably supports a rotating shaft to which a gear to be mated with a mating gear is connected to the other end. 3. The double-row angular contact ball bearing according to claim 1 or 2, wherein the bearing is a double-row angular contact ball bearing. Used in a hydrogen circulation pump, comprising an outer ring having an outer ring raceway surface on the inner periphery, an inner ring having an inner ring raceway surface on the outer periphery, a plurality of the outer ring raceway surfaces and the inner ring raceway surfaces, the outer ring raceway surface and the inner ring raceway surface. A double row angular contact ball bearing comprising a plurality of rolling elements disposed between the
Shoulders are formed on the inner periphery of the outer ring and the outer periphery of the inner ring, the height hD of the shoulder portion of the outer ring satisfies the following formula (5), and the height hd of the shoulder portion of the inner ring is A double-row angular contact ball bearing characterized by satisfying the following formula (6).
0.15×(Dα-dp)≦hD≦0.35×(Dα-dp) (5)
0.15×(dp-dα)≦hd≦0.35×(dp-dα)...(6)
Dα: diameter of the contact point of the outer ring with the rolling element dα: diameter of the contact point of the inner ring with the rolling element dp: pitch diameter of the rolling element

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