Retainer-equipped roller

Abstract

This retainer-equipped roller comprises a plurality of rollers and a retainer (2) for holding the rollers. The retainer (2) comprises: a pair of ring members (4) that face either end of each roller in the axial direction; and a plurality of column parts (5) that are installed so as to span across the outer diameter parts of the pair of ring members (4) and that are provided at regular intervals in the circumferential direction such that the rollers can enter. The inner diameter part of each ring member (4) is provided with a roller holding claw (6) which prevents the roller from slipping out to the inner diameter side of the retainer. A retainer radial direction chamfer length (B) satisfies the following relationship with respect to the retainer wall thickness (A).　0 < B / A ≤ 1.6

Description

Roller and cage assembly Related Applications

[0001] This application claims priority from Japanese Patent Application No. 2023-188815, filed November 2, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a roller and cage assembly used in, for example, a double row.

[0003] To ensure the load capacity of a roller and cage assembly, it is necessary to increase the roller packing ratio.When increasing the roller packing ratio, a roller and cage assembly that ensures load capacity by eliminating the pillars on the inner diameter side of the cage is common, but this causes the rollers to separate on the inner diameter side of the cage, making it difficult to assemble into mechanical devices.

[0004] Furthermore, when roller and cage assemblies are operated in double rows, each roller and cage assemblies generates a thrust component force (hereinafter referred to as induced thrust force) due to roller skew, requiring the mechanical device to have a support mechanism for the thrust force. For roller and cage assemblies used in double rows, it is desirable that they have a high load capacity, are easy to assemble into the mechanical device, and have a reduced number of parts.

[0005] As shown in Figure 6, a conventional cage has roller retaining pawls 52 provided between adjacent rollers 50 on the inner diameter portion of annular portion 51 to prevent rollers 50 from slipping out toward the inner diameter side of the cage (Patent Document 1). Furthermore, as shown in Figure 7, the filling rate of rollers 50 is specified to be 80% or more. This ensures both the load capacity of the roller and cage assembly and ease of assembly of the mechanical device.

[0006] In another conventional example, as shown in Figure 8, the end faces 53a of the rollers 53 are flat (Patent Document 2). This allows the contact length to be longer, ensuring a high load capacity. In addition, the surface 54a of the spacer 54, which is disposed opposite the end faces 53a of the rollers 53, is tapered. This reduces the sliding area between the ends of the rollers 53 and the spacer 54, effectively reducing sliding resistance during operation.

[0007] JP 2005-106211 A JP 2009-216112 A

[0008] In Patent Document 1, roller retaining pawls are provided on the inner diameter side of the cage, and the roller filling rate is set to 80% or more, thereby achieving both a high load capacity for the roller and cage assembly and improved assembly into the device. However, when used in double rows, there is a risk that the roller retaining pawls will come into contact with the rollers due to the induced thrust force of adjacent roller and cage assemblies.

[0009] In Patent Document 2, a tapered spacer is disposed opposite the end face of the roller to reduce sliding resistance during operation. However, the need for the spacer increases the number of parts.

[0010] An object of the present invention is to provide a roller and cage assembly that ensures high load capacity, is easy to assemble into a mechanical device, and prevents an increase in the number of parts.

[0011] The roller and cage assembly of the present invention comprises a plurality of rollers and a cage that holds these rollers, the cage comprising a pair of ring members facing both axial ends of each of the rollers, and a plurality of pillar portions that are installed across the outer diameter portions of the pair of ring members and are provided at regular intervals in the circumferential direction, and into which the rollers fit, the inner diameter portion of each of the ring members is provided with roller retaining claws that prevent the rollers from slipping out towards the inner diameter side of the cage, the radial thickness of the pillar portions being defined as cage thickness A and the length of the radially extending portion of the chamfer connecting the outer diameter surface and width surface of the cage being defined as cage radial chamfer length B, and the relationship between cage thickness A and cage radial chamfer length B satisfies the following relationship: 0<B / A≦1.6 The "cage thickness" refers to the radial thickness of the pillar portions or the axial thickness of the ring members. The "length of the cage radial chamfer" refers to the length of the radially extending portion of the chamfer connecting the outer diameter surface and the width surface of the cage.

[0012] With this configuration, the cage radial chamfer length B relative to the cage wall thickness A satisfies the relationship 0 < B / A ≦ 1.6. When a load equivalent to the induced thrust force is applied to this caged roller assembly, the cage can rotate smoothly without contacting the rollers. If the cage radial chamfer length B is longer relative to the cage wall thickness A, i.e., if B / A exceeds 1.6, the bending moment applied to the ring member increases, causing significant axial inward deformation of the ring member, which may result in rubbing or wear of the cage. In this application, chamfering refers to a configuration in which an oblique surface is added to the corner where two surfaces intersect. This definition conforms to JIS B 3401. Chamfering can be formed not only by cutting, but also by press processing.

[0013] The cage has a gate-shaped configuration with a pair of ring members and multiple pillars, allowing for a higher roller packing rate and ensuring a higher load capacity than cages with pillars on the inner diameter side. Because roller retaining claws are provided on the inner diameter of each ring member, the rollers do not separate to the inner diameter side of the cage during assembly, making it easier to assemble into mechanical devices. Because the roller retaining claws are provided on the inner diameter of each ring member, preventing the rollers from falling out prevents the addition of additional parts and reduces costs.

[0014] In double-row roller and cage assemblies, adjacent cages in the axial direction may be in contact with each other. In this case, it is possible to rotate the cage smoothly without adding parts such as spacers to reduce sliding resistance during operation.

[0015] In a configuration in which the rollers with cages roll in contact between the inner diameter hole of an outer member and a shaft, the relationships C1 > C3 and C2 > C4 may be satisfied, where C1 is the radial clearance between the outer diameter of the shaft and the inner diameter of the roller retaining claw, C2 is the radial clearance between the outer diameter of the roller retaining claw and the position where it intersects with the rollers, C3 is the radial clearance between the inner diameter of the pillar portion and the position where it intersects with the rollers, and C4 is the radial clearance between the inner diameter of the outer member and the outer diameter of the pillar portion.

[0016] Ensuring a cage clearance is one way to prevent the roller retaining claws of the cage from contacting the rollers or shaft while the roller and cage assembly is in operation. With this configuration, by satisfying the relationships C1 > C3 and C2 > C4, it is possible to achieve smooth operation without the roller retaining claws coming into contact with the rollers or shaft.

[0017] The surface roughness of the side surface of the ring member, which is the width surface of the cage, may be Rmax = 12.5s or less. In this case, smooth operation can also be achieved.

[0018] The roller retaining claws may be bent piece-shaped roller retaining claws provided between adjacent rollers on the inner diameter portion of the ring member. In this case, by bending the roller retaining claws after the rollers are assembled, the rollers can be made to be inseparable from the cage, which provides excellent assembly ease into mechanical devices.

[0019] The double-row roller and cage assembly may be inserted into an eccentric shaft, in which case the double-row roller and cage assembly can be used under conditions where eccentric motion occurs under high load conditions.

[0020] Any combination of at least two features disclosed in the claims and / or the specification and / or the drawings is included in the present invention. In particular, any combination of two or more of the claims is included in the present invention.

[0021] The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are merely for illustration and explanation and should not be used to define the scope of the present invention. The scope of the present invention is defined by the accompanying claims. In the accompanying drawings, the same reference numerals in multiple drawings indicate the same or corresponding parts.

[0023] Fig. 3A is a perspective view of a roller and cage assembly according to a first embodiment of the present invention.

[0024] Fig. 3B is a longitudinal sectional view of the roller and cage assembly used in double rows.

[0025] Fig. 3C is an enlarged sectional view of the cage of the roller and cage assembly.

[0026] Fig. 3D is a cross-sectional view of a main part of the roller and cage assembly.

[0027] Fig. 3E is a longitudinal sectional view of a conventional roller and cage assembly.

[0028] Fig. 3F is a cross-sectional view of the conventional roller and cage assembly.

[0029] Fig. 3G is a cross-sectional view of another conventional roller and cage assembly.

[0022] [First embodiment] A roller and cage assembly according to an embodiment of the present invention will be described with reference to Figures 1 to 5. This roller and cage assembly is used in double rows in applications such as industrial machinery, vehicles, etc. However, it is also possible to use the roller and cage assembly in a single row.

[0023] <Overall structure of roller and cage assembly> As shown in Figure 1, a roller and cage assembly 1 comprises a cage 2 and a plurality of rollers 3. The cage 2, which holds the plurality of rollers 3, has a pair of ring members 4 and a plurality of pillar portions 5. The pair of ring members 4 face both axial ends of each roller 3, in other words, they are a pair of annular members that face each other and are spaced apart in the axial direction.

[0024] The multiple column sections 5 are installed across the outer diameter sections of the pair of ring members 4 and are provided at regular intervals in the circumferential direction, with pockets formed between adjacent column sections 5, 5 in which the rollers 3 fit. The inner diameter section of each ring member 4 is provided with roller retaining claws 6 that prevent the rollers 3 from slipping out toward the inner diameter side of the cage. The rollers 3 are made of, for example, bearing steel or the like and are, for example, needle rollers. However, the rollers 3 may also be cylindrical rollers. In this specification, the "axial direction" refers to the direction along the axis AX of the roller and cage assembly 1 or the direction parallel to the axis AX. The "radial direction" refers to the direction perpendicular to the line that forms the "axial direction."

[0025] As shown in Figure 2, the roller and cage assemblies are used by being inserted in double rows on a shaft 7, with the roller and cage assemblies 1a, 1b arranged adjacent to each other in the axial direction. The shaft 7 may be an eccentric shaft. Of the roller and cage assemblies 1a, 1b used in double rows, the cages adjacent to each other in the axial direction are in contact with each other. During operation, the roller and cage assemblies 1a on one axial side support the induced thrust force Fa of the roller and cage assemblies 1b on the other axial side at the radial chamfer position 4a1 of the cage 2. The radial chamfer position 4a1 is the position where the width dimension (axial dimension) of the cage 2 is at its maximum.

[0026] <Cage> The pillar portions 5 are formed with a diameter larger than the pitch circle diameter of the roller array and extend in the axial direction. As shown in Fig. 3A, the roller retaining claws 6 are bent piece-shaped roller retaining claws provided in the areas between adjacent rollers on the inner diameter portion of the ring member 4. As shown in Fig. 4, the roller retaining claws 6 are inclined axially inward as they move toward the inner diameter side. The bending angle θ of the roller retaining claws 6 with respect to the ring member 4 is, for example, 30° to 90°.

[0027] <Manufacturing method> As shown in Figure 3A, the cage is formed into a gate shape by, for example, cutting out a pipe material and then pressing or welding it. The cage itself is then subjected to a known heat treatment to achieve a predetermined hardness. After the heat treatment, rollers are assembled into the cage, and the inner diameter portion of the ring member 4 is bent axially inward. The bending is performed by pressing, spinning, or the like. As a result, roller retaining claws 6 are formed on the inner diameter portion of the ring member 4.

[0028] <Cage Wall Thickness and Radial Chamfer on Outer Diameter Side of Cage> To ensure the load capacity of a roller and cage assembly, it is necessary to increase the roller packing ratio around the entire circumference of the cage. In order to increase the roller packing ratio, the pillars on the inner diameter side are naturally eliminated, resulting in a gate-shaped cage. The roller packing ratio P is given by the following formula: P = (d × n) / (D × π), where d is the roller diameter, n is the number of rollers, and D is the pitch circle diameter of the roller arrangement. In the case of a gate-shaped cage, as shown in Figure 3B, when supporting the induced thrust force Fa, the cage ring member 4 is deformed inward, making it easier for the rollers 3 (Figure 2) and roller retaining claws 6 (Figure 2) to come into contact, hindering smooth rotation.

[0029] 3A , the cage 2 supports the induced thrust force Fa at the radial chamfer position 4a1. If the cage thickness is A and the cage radial chamfer length is B, as the cage radial chamfer length B becomes longer relative to the cage thickness A, the bending moment acting on the ring member 4 of the cage 2 increases, and the inward deformation of the ring member 4 increases.

[0030] <Test Verification> As examples, a number of test pieces were used in which the cage wall thickness A and the cage radial chamfer length B were changed, and tests were conducted to verify whether the roller and cage assembly would rotate smoothly when a load equivalent to the induced thrust force Fa was applied. As comparative examples, a roller and cage assembly having a cage of approximately the same shape as the examples, but without roller retention claws, was also tested. In Table 1, the examples are represented as "with claws" and the comparative examples as "without claws." The cage wall thickness A was measured at the center position of the column portion 5 in the axial direction.

[0031]

[0032] It was confirmed that the roller and cage assemblies of the example rotate smoothly when the cage wall thickness A is 1.6 or less relative to the cage radial chamfer length B. In other words, when 0 < B / A ≦ 1.6 is satisfied, the cage can rotate smoothly without contacting the rollers. Even when used in a single row, the roller and cage assemblies support the induced thrust force generated by the skew of the rollers at the load application point of the cage itself, so the same can be said about the results of the above test. In the comparative example without roller retaining claws, the cage rotates smoothly without contacting the rollers regardless of B / A, but the rollers separate toward the inner diameter of the cage, making it difficult to assemble into mechanical devices.

[0033] <Cage Clearance> As shown in Figure 5, ensuring a cage clearance is one way to prevent the roller retaining claws 6 of the cage from contacting the rollers 3 or the shaft 7 during operation. Specifically, for a configuration in which the rollers and cage are in rolling contact between the bore 8a of the outer member 8 and the shaft 7, the following relationship must be satisfied.

[0034] C1>C3 and C2>C4 However, C1: radial clearance between the outer diameter of the shaft 7 and the inner diameter 6b of the roller retaining claw 6 C2: radial clearance from the outer diameter 6a of the roller retaining claw 6 to the position where it intersects with the roller 3 radially outward C3: radial clearance from the inner diameter 5b of the column portion 5 to the position where it intersects with the roller 3 radially inward C4: radial clearance between the inner diameter 8a of the outer member 8 and the outer diameter 5a of the column portion 5 By satisfying the relationships C1>C3 and C2>C4, it is possible to achieve smooth operation without the roller retaining claw 6 coming into contact with the roller 3 or the shaft 7.

[0035] As shown in Figure 4, the surface roughness of the ring member side surface 4a, which is the width surface of the cage, may be Rmax = 12.5s or less. In this way, even when the maximum height Rmax of the surface roughness of the ring member side surface 4a is 12.5s or less, smooth operation can be achieved.

[0036] <Function and Effect> With the roller and cage assembly 1 of Figure 1 explained above, as shown in Figure 3A, the length B of the cage radial chamfer relative to the cage wall thickness A satisfies the relationship 0 < B / A ≦ 1.6. When a load equivalent to the induced thrust force is applied to this roller and cage assembly, the cage 2 can rotate smoothly without coming into contact with the rollers. If the length B of the cage radial chamfer is long relative to the cage wall thickness A, in other words, if B / A exceeds 1.6, the bending moment applied to the ring member 4 increases, causing significant deformation of the ring member 4 in the axially inward direction, which may result in rubbing or wear of the cage 2.

[0037] The cage 2 has a gate-shaped configuration with a pair of ring members 4 and multiple pillars 5, allowing for a higher roller packing rate and ensuring a higher load capacity than cages with pillars on the inner diameter side. Because roller retaining claws 6 are provided on the inner diameter of each ring member 4, the rollers do not separate to the inner diameter side of the cage during assembly, making it easier to assemble into mechanical devices. The roller retaining claws 6 are provided on the inner diameter of each ring member 4, preventing the need for additional parts to prevent rollers from falling out, thereby reducing costs.

[0038] As shown in Figure 2, the roller retaining claws 6 are bent piece-shaped roller retaining claws provided between adjacent rollers on the inner diameter portion of the ring member 4. Therefore, by bending the roller retaining claws after the rollers are assembled, the rollers 3 can be made to be inseparable from the cage 2, providing excellent assembly ease into mechanical devices. When double-row roller and cage assemblies 1a, 1b are inserted into an eccentric shaft, the double-row roller and cage assemblies 1a, 1b can be used under conditions that cause eccentric motion under high load conditions.

[0039] As described above, the preferred embodiment has been described with reference to the drawings, but various additions, modifications, and deletions can be made without departing from the spirit of the present invention. Therefore, such additions, modifications, and deletions are also included in the scope of the present invention.

[0040] DESCRIPTION OF SYMBOLS 1, 1a, 1b... roller and cage assembly 2... cage 3... roller 4... ring member 5... column portion 6... roller holding claw 7... shaft 8... outer member

Claims

1. A roller and cage comprising a plurality of rollers and a cage for retaining said rollers, said cage comprising a pair of ring members facing both axial ends of each of said rollers, and a plurality of pillar portions disposed at regular intervals in the circumferential direction across the outer diameter portions of said pair of ring members, and in which roller retaining claws for preventing said rollers from slipping out towards the inner diameter side of the cage are provided on the inner diameter portion of each of said ring members, wherein the radial thickness of said pillar portions is cage thickness A, and the length of the radially extending portion of the chamfer connecting the outer diameter surface and width surface of the cage is cage radial chamfer length B, and wherein the relationship between cage thickness A and cage radial chamfer length B satisfies the following relationship: 0<B / A≦1.6 2. A roller and cage assembly as claimed in claim 1, in which the rollers and cage assembly are used in a double row, and in which adjacent cages in the axial direction are in contact with each other.

3. A roller and cage assembly as claimed in claim 1 or claim 2, in which the roller and cage assembly is configured to roll in contact between the inner diameter hole of an outer member and a shaft, wherein, assuming that the radial clearance between the outer diameter of the shaft and the inner diameter of the roller retaining claw is C1, the radial clearance from the outer diameter of the roller retaining claw to the position where it intersects with the rollers radially outward is C2, the radial clearance from the inner diameter position of the roller retaining claw to the position where it intersects with the rollers radially outward is C3, and the radial clearance between the inner diameter of the column portion to the position where it intersects with the rollers radially inward is C3, and the radial clearance between the inner diameter of the outer member and the outer diameter of the column portion is C4, then the roller and cage assembly satisfies the relationships C1>C3 and C2>C4.

4. A roller and cage assembly as claimed in claim 1 or 2, in which the surface roughness of the ring member side surface, which is the cage width surface, is Rmax = 12.5s or less.

5. A roller and cage assembly as claimed in claim 1 or 2, wherein the roller retaining claw is a bent piece-shaped roller retaining claw provided in the portion between adjacent rollers on the inner diameter portion of the ring member.

6. A roller and cage assembly as claimed in claim 2, in which the rollers and cage assembly used in double rows are inserted onto an eccentric shaft.

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