JPH11336770A - Needle roller bearing for transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure where lubricating oil is easy to pass in the axial direction by taking a guide form of a retainer as inside diameter guide, and specifying the clearance gap between the inside diameter of a transmission gear and the outside diameter of the retainer to the roller diameter. SOLUTION: A clearance gap J between the inside diameter of the inner peripheral surface 4a of a transmission gear and the outside diameter of a retainer 2 is set to 15 to 20% of the roller diameter (d). In the case where the guide form of the retainer 2 is inside diameter guide, the inside diameter of the retainer 2 is guided by the outside diameter of a rotary shaft 5, so that the retainer 2 is offset to the rotary shaft 5 side with respect to the center line I of the roller 3. Accordingly, the clearance gap J is larger than the clearance gap K between the inscribed circle of the roller 3 and the inner peripheral surface of the retainer 2. Accordingly, even if lubricating oil is stuck to the inside diameter of the housing inner peripheral surface 4a of the transmission gear, a flow of lubricating oil is not inhibited by the retainer to enter the clearance gap J, and passed through the roller 13 to enter the clearance gap J on the other end side, and after that, the oil flows to the peripheral parts. Accordingly, thermal deformation and separation of the roller 3 can be prevented to improve durability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a needle roller bearing (needle bearing) for supporting a transmission gear such as an idler gear in a transmission of an automobile, and more particularly, to an improvement in the shape of a cage. Since the lubricating oil permeability of the needle roller bearing in the axial direction is improved, the lubricating performance of the needle roller bearing and the synchronous meshing device can be improved.

[0002]

2. Description of the Related Art FIG. 7 shows an example of a transmission for an automobile. FIG. 7 is a sectional view showing a part of a transmission of an automobile.

In FIG. 7, reference numeral 201 denotes a main shaft which is a rotating shaft. The main shaft 201 is rotatably housed in a transformer case 202 in an axial direction. A second speed main gear 204 having a clutch gear 203 and a first speed main gear 206 having a clutch gear 205 are rotatably supported on the main shaft 201, respectively.
A cone-type synchronous meshing device 207 is provided between the second speed main gear 204 and the first speed main gear 206, and the synchronous meshing device 207 switches between the second speed main gear 204 and the first speed main gear 206. Reference numeral 208 denotes a counter shaft, and the counter shaft 208 is a main shaft 201
And is rotatably housed in the transformer case 202. A second speed counter gear 209 and a first speed counter gear 210 are integrally formed on the counter shaft 208 in the axial direction. The second speed main gear 204 meshes with the second speed counter gear 209, and the first speed counter gear 210 engages with the first speed counter gear 210. The main gears 206 mesh with each other.

A second-speed needle bearing 2 is provided between the shaft hole 211 of the second-speed main gear 204 and the main shaft 201.
A first-speed needle bearing 214 is provided between the shaft hole 213 of the first-speed main gear 206 and the main shaft 201.

The first speed main gear 206 is formed with a concave portion 215 for receiving a lubricating oil splashed by a reverse main gear (not shown) provided on the right side of the first speed main gear 206 in FIG. The lubricating oil received by the concave portion 215 passes through the needle bearing 214 from one end surface 217 of the shaft hole 213 of the first speed main gear 206, and enters the inside of the synchronous meshing device 207 through the other end surface 218. Also,
A concave portion 219 is also formed in the second speed main gear 204, and the concave portion 219 receives lubricating oil splashed by a third speed main gear (not shown) provided on the left side of the second speed main gear 204 in FIG. The lubricating oil received in the recess 219 is the second speed main gear 204
From one end face 221 of the shaft hole 211 through the needle bearing 212 and from the other end face 222 to the synchronous meshing device 2.
07.

FIG. 8 shows a first-speed needle bearing 21 shown in FIG.
FIG.

In FIG. 8, reference numeral 315 denotes a cage formed in a cylindrical body, and the cage 315 holds a roller 316. One roller 316 is held in the width direction of the cage 315, and the rollers 316 are held in a row in the circumferential direction of the cage 315. A plurality of holding holes (not shown) are formed in the cage 315 in the circumferential direction, and the rollers 316 are held by holding portions (not shown) formed in the cage 315. A bent portion 315a is formed at both ends of the cage 315,
A concave portion 315 is provided between the bent portions 315a.
b is formed. “a” is a dimension from the upper outer periphery of the roller 316 to the outer periphery of the lower roller 316, and this dimension indicates a hole diameter of the first speed main gear 206, and the hole diameter “a” is set to, for example, 61 mm. b is the upper roller 316
Is the dimension from the inner circumference of the lower roller 316 to the inner circumference of the lower roller 316. This dimension indicates the shaft diameter of the main shaft 201, and the shaft diameter b is set to, for example, 55 mm. c indicates the outer diameter of the cage 315, and the outer diameter c is set to, for example, about 61 mm. d indicates the inner diameter of the cage 315,
The inner diameter d is set to, for example, about 57 mm. e
Indicates the width of the cage 315, and the width e of the cage 315
Is set to, for example, about 40 mm. f indicates a protruding length in which the cage 315 protrudes from the roller 316 to both sides,
The projection length f is set to, for example, 4 to 5 mm. g
Indicates the thickness of the bent portion 315a of the cage 315, and the thickness g of the bent portion 315a is set to, for example, 2 mm. h indicates the diameter of the roller 316, and the diameter h of the roller 316 is set to, for example, 3 mm.

The cage 315 is offset toward the shaft support hole 213 with respect to the center line i of the roller 316. Therefore, the gap j between the outer periphery of the cage 315 and the outer periphery of the cage 316
Almost no. That is, the gap j is, for example, 0.
It is set to about 1 mm, and the gap j is very small. The gap k between the inner circumference of the cage 315 and the inner circumference of the cage 316 is equal to the gap j.
It is larger, for example, set to about 1 mm. Note that the second-speed needle bearing 212 also has a similar configuration except for the dimensions.

[0009]

As shown in FIG. 9, since the cage 315 is offset toward the shaft support hole (gear side) with respect to the center line i of the roller 316, the outer periphery 316 of the cage 315 There is almost no gap j with the outer periphery, and the cage 315 prevents the lubricating oil coming from one end side from flowing to the other end side as shown by the arrow m. Therefore, the lubricating oil does not flow into the other end as shown by the arrow n. Therefore, the amount of lubricating oil passing through the needle roller bearing is reduced, and there is a possibility that the roller 316 may be thermally deformed or peeled off, thereby deteriorating the durability of the needle roller bearing itself. Further, since the lubricating oil does not easily pass through the needle roller bearing, the lubricity of peripheral parts is also deteriorated. As a result, there is a shortage of lubricating oil in the synchronous meshing device, the performance of the synchronous meshing device is deteriorated, and the operation feeling of the vehicle is deteriorated.

A main object of the present invention is to provide a needle roller bearing for a transmission having a structure in which lubricating oil easily passes in the axial direction.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, a synchromesh is located at one end of a transmission gear, and lubricating oil is supplied from the other end of the transmission gear. A needle roller bearing for rotatably supporting the transmission gear in a transmission on a rotating shaft, comprising: a plurality of needle rollers interposed between the shaft and the transmission gear; A cage for holding at an interval is provided, and the guide type of the cage is an inner diameter guide, and a clearance between the transmission gear inner diameter and the outer diameter of the cage is set to 15 to 20% of the roller diameter. With this configuration, the lubricating oil passage in the axial direction is improved as compared with the conventional type. Since the lubricating oil tends to flow toward the outer diameter side due to the centrifugal force caused by the rotation, it is considered that the lubricating oil flows more easily as the clearance between the inner diameter of the transmission gear and the outer diameter of the retainer is larger. If the clearance between the inner diameter of the transmission gear and the outer diameter of the cage is less than 10% of the roller diameter, it is considered that lubricating oil is difficult to pass through.
% Was the lower limit. On the other hand, in a region where the clearance between the inner diameter of the transmission gear and the outer diameter of the cage exceeds 20% of the roller diameter, the contact guide of the rollers becomes unstable.

From the viewpoint of facilitating the flow of the lubricating oil in the axial direction, it is preferable that the outer diameter of the retainer is straight as in the invention of claim 2, and a concave or convex portion is provided at the central portion in the axial direction. It is more advantageous for the degree of change from the outer diameter surface to be smaller.

According to the third aspect of the present invention, there are provided annular flanges located at both ends in the axial direction, and a plurality of pillars arranged at equal intervals in the circumferential direction and extending in the axial direction to connect the flanges. Can be manufactured by bending a flat plate-shaped material provided with portions corresponding to the flange portion and the column portion into an annular shape and butt-welding the ends. In this case, it is advantageous in the following respects to provide a step by making the inner diameter of the flange larger than the inner diameter of the pillar. That is, in the welding cage, the portion of the weld bulge on the inner diameter side of the flange needs to be removed in order to prevent interference with the mating shaft. However, by providing the above-described step, the removal operation can be omitted. Further, the provision of the step makes it easier for the lubricating oil to enter between the retainer and the shaft.

According to a fourth aspect of the present invention, a synchronous meshing device is located at one end of a transmission gear, and the transmission gear is rotatable about a rotation shaft in a transmission to which lubricating oil is supplied from the other end of the transmission gear. A needle roller bearing for supporting, comprising: a plurality of needle rollers interposed between a shaft and a transmission gear; and a retainer for holding the needle rollers at equal intervals in a circumferential direction. The guide type of the container is an outer diameter guide, and the outer diameter of the retainer is straight or the concave step at the center of the outer diameter of the retainer is suppressed to 15% or less of the roller diameter. This allows
The lubricating oil permeability in the axial direction is improved as compared with the conventional type. Here, as in the invention of claim 5, an annular flange portion located at both ends in the axial direction and a plurality of pillar portions arranged at equal intervals in the circumferential direction and extending in the axial direction to connect the flange portions. Can be manufactured by welding. In this case, by providing the step with the outer diameter of the flange smaller than the outer diameter of the pillar, the same advantage as described above with respect to claim 3 can be obtained. Preferably, the step is 5 to 15% of the roller diameter (claim 6). This is because, within such a numerical range, interference of the welded portion can be prevented, and the passage of the lubricating oil in the axial direction is not prevented.

In the needle roller bearing having the above-described structure, since the lubricating oil easily passes in the axial direction, the lubricating oil from one end of the needle roller bearing passes through the needle roller bearing after entering the gap. And enters the gap at the other end, and then flows to the peripheral components. Therefore, thermal deformation and peeling of the rollers can be prevented, and the durability of the needle roller bearing itself can be improved. Further, since the amount of the lubricating oil to be passed increases, the lubricity of peripheral parts can be improved. Therefore, a synchronous meshing device is located at one end of the transmission gear, and a needle roller for rotatably supporting the transmission gear on a rotating shaft in a transmission to which lubricating oil is supplied from the other end of the transmission gear. When used as a bearing, the lubricating oil has good permeability, so that not only the needle roller bearing but also the synchronous meshing device has improved lubricity. As a result, the performance of the synchromesh device can be prevented from deteriorating, and the operation feeling in the vehicle can be prevented from deteriorating.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS.
5, FIG. 1 to FIG. 4 show the case of the inner diameter guide, and FIG. 5 shows the case of the outer diameter guide. The structure of the transmission in which the synchromesh is located at one end of the transmission gear and lubricating oil is supplied from the other end of the transmission gear is as described above with reference to FIG.

First, the embodiment shown in FIGS. 1 to 3 will be described. In FIG. 1 which is a half cross-sectional view of a needle roller bearing with a retainer, a needle roller bearing (1) includes a retainer (2) formed in a cylindrical body and a pocket ( 2a) and a roller (3) rotatably housed in 2a). As shown in FIGS. 2 and 3, the needle roller bearing (1) includes an inner peripheral surface (4 a) of the transmission gear (4) and a rotating shaft (5) that rotatably supports the transmission gear (4 a). It is incorporated between the outer peripheral surface (5a). The rollers (3) are held at equal intervals in the circumferential direction by the retainer (2). As shown in the drawing, one roller (3) is arranged in a row in the width direction of the retainer (2), and thus is arranged in a row in the circumferential direction. Although illustration is omitted, 2
It is also possible to arrange them in rows.

In order to manufacture the cage (2), various methods such as cutting, molding and the like can be adopted. The case of a welded cage will be described as an example. A pair of parallel flanges (2b) extending in the longitudinal direction and a pair of parallel flanges (2b) extending in a direction orthogonal to the flanges are formed by punching a strip-shaped metal sheet to form one or two rows of pockets (2a). A material having a plurality of pillars (2c) connecting the collar parts is obtained. A pocket (2a) is formed between adjacent pillar portions (2c). When this material is bent in an annular shape and the ends are butt-welded, a cage (2) having a desired shape is obtained. When the flange portion (2b) and the pillar portion (2c) are continuously flush with each other without a step, the flange (2b) and the column portion (2c) are not connected to the shaft (in the case of the inner diameter guide) or the transmission gear (in the case of the outer diameter guide). In order to prevent interference, it is necessary to remove the raised portion by welding.

In FIG. 1, reference numeral A denotes an upper roller (3)
Indicates the dimension from the outer circumference of the roller to the outer circumference of the lower roller (3),
This dimension indicates the hole diameter of the transmission gear (4). The hole diameter A is set to, for example, 61 mm. B indicates the dimension from the inner circumference of the upper roller (3) to the inner circumference of the lower roller (3), and this dimension is the diameter of the rotating shaft (5) that rotatably supports the transmission gear (4). Is shown. The shaft diameter B is set to, for example, 55 mm. C indicates the outer diameter of the retainer (2), and the outer diameter C of the retainer (2) is set to, for example, 60 mm. D indicates the inner diameter of the retainer (2), and the inner diameter D of the retainer (2) is set to, for example, 55 mm. The circumscribed circle of the roller (3), that is, the gap (J) between the inner diameter of the inner peripheral surface (4a) of the transmission gear and the outer diameter of the retainer (2) is defined as 1 of the roller diameter (d).
Set 5-20%.

Here, when the guide type of the retainer (2) is the inner diameter guide, the inner diameter of the retainer (2) is guided by the outer diameter of the rotating shaft (5). It is offset toward the rotation axis (5) with respect to the center line (I) of 3). Therefore, the gap (K) between the inscribed circle of the roller (3) and the inner peripheral surface of the cage (2) is, for example, only about 0.1 mm, but on the other hand, the gap (K) on the outer peripheral surface of the cage (2) is (3). ) Is set to, for example, about 0.5 mm. Thus, the outer peripheral surface of the retainer (2) (3)
The gap (J) with the circumscribed circle of the needle roller bearing is wide, for example, about 0.5 mm. Therefore, when the transmission gear using the needle roller bearing (1) is rotating, lubricating oil is generated by centrifugal force. The retainer (2) prevents the flow of the lubricating oil even if it is stuck to the inner diameter of the inner peripheral surface (4a) of the transmission gear (4) (the shaft support hole of the transmission gear: see FIG. 8). Without
It enters the gap (J), passes through the roller (3), enters the gap (J) on the other end side, and then flows to peripheral components. Therefore, it is possible to prevent the roller (3) from being thermally deformed or peeled off, and to improve the durability of the needle roller bearing (1) itself. Further, since the amount of the lubricating oil passing therethrough increases, the lubricating properties of the peripheral components of the needle roller bearing (1) can be improved.

In order to enhance the passage of the lubricating oil, the cage (2)
Is preferably a straight shape having no step in the axial direction. In the case where a shallow concave portion is formed in the central portion in the axial direction, it is preferable to suppress the step amount to 15% or less of the roller diameter. The inner diameter of the retainer (2) may be straight, or, as shown in FIG. 4A, a concave portion may be provided in the axially central portion of the inner peripheral surface of the retainer (2). In the cage (2) shown in FIG. 4 (b), the inner diameter of the flange (2b) is made larger than the inner diameter of the column (2c) so that the connection between the flange (2b) and the column (2c) can be made. A step (2d) is provided. In particular, in the case of the welding cage described above, the bulge due to welding does not interfere with the outer peripheral surface (5a) of the rotating shaft (5) due to the presence of the step (2d). Therefore, post-processing which has been performed to remove such bulges after welding can be omitted, and the manufacturing process can be simplified.

FIG. 5 shows an embodiment of a needle roller bearing retainer in which the guide type is an outer diameter guide. In this case, the outer diameter of the cage (2) is straight, or
When a shallow concave portion is formed in the central portion in the axial direction as shown in (a), it is preferable to suppress the step amount to 15% or less of the roller diameter in order to enhance the passage of the lubricating oil.

In the cage (2) shown in FIG. 5 (b), the outer diameter of the flange (2b) is made smaller than the outer diameter of the column (2c), and the flange (2b) and the column (2c) are formed. Step (2
d) is provided. The step (2d) is 5 to 15% of the roller diameter
Set to the range. As described above with reference to FIG. 4B, particularly in the case of the welding cage, the bulge due to welding interferes with the inner peripheral surface (4a) of the transmission gear (4) due to the presence of the step (2d). Nothing. Therefore, post-processing which has been performed to remove such bulges after welding can be omitted, and the manufacturing process can be simplified.

FIGS. 1, 4 (a), 4 (b), 5
For each of Examples 1 to 4 shown in (b) and the conventional example shown in FIG. 8, a comparative test of the lubricating oil passage property due to the difference in the cage shape was performed. The test equipment used is as follows. An outer ring simulating a gear is rotatably mounted on a horizontal shaft via a test bearing, and a lubricating oil supply hole is opened toward one end surface of the outer ring. A felt for absorbing the oil was applied to the other end face of the outer ring, a fixed amount of lubricating oil was supplied from a lubricating oil supply hole, and all the passed lubricating oil was absorbed by the felt. A seal was attached so that all the lubricating oil that did not pass could be recovered from the lubricating oil recovery hole.

Then, the outer ring was rotated by a motor, and the amount of lubricating oil passing through the inside of the test bearing was measured with respect to the amount of lubricating oil supplied per unit time. The difference in weight of the felt before and after the test was determined as the amount of the passed lubricant.

FIG. 6 shows the test results.

[0027]

As described above, according to the needle roller bearing of the present invention, the cage does not prevent the lubricating oil from flowing from one end to the other end, and the lubricating oil is supplied to the needle roller bearing. Of the needle roller bearing itself can be improved. In addition, since the amount of the lubricating oil passing therethrough is increased, the lubricating properties of peripheral parts can be improved. Can be improved, and as a result, the operation of the synchronous meshing device becomes smooth, and the operation feeling of the vehicle does not deteriorate.

[Brief description of the drawings]

FIG. 1 is a half sectional view of a needle roller bearing.

FIG. 2 is a cross-sectional view of the assembled needle roller bearing.

3 (a) is a cross-sectional view along the center of the roller in FIG. 2 (b) is a partial plan view of a needle roller bearing

FIG. 4 is a cross-sectional view similar to FIG. 3 showing another embodiment.

FIG. 5 is a cross-sectional view similar to FIG. 3 showing another embodiment.

FIG. 6 is a diagram showing a comparison test result.

FIG. 7 is a partial sectional view of a transmission.

FIG. 8 is a cross-sectional view of a needle roller bearing with a cage showing a conventional technique.

FIG. 9 is an explanatory diagram of a problem.

[Explanation of symbols]

 1: needle roller bearing 2: cage 2a: pocket 2b: flange 2c: pillar 2d: step 3: roller 4: transmission gear 4a: inner peripheral surface 5: rotating shaft 5a: outer peripheral surface A: hole diameter B: shaft Diameter C: Outer diameter of cage D: Inner diameter of cage d: Roller diameter J, K: Clearance

Claims (6)

[Claims] A needle for rotatably supporting, on a rotating shaft, the transmission gear in a transmission in which a synchromesh device is located at one end of the transmission gear and lubricating oil is supplied from the other end of the transmission gear. A roller bearing, comprising: a plurality of needle rollers interposed between a shaft and a transmission gear; and a cage for holding the needle rollers at equal intervals in a circumferential direction. A needle roller bearing for a transmission, wherein an inner diameter guide is provided, and a clearance between an inner diameter of a transmission gear and an outer diameter of a cage is set to 15 to 20% of a roller diameter. 2. The needle roller bearing for a transmission according to claim 1, wherein the outer diameter of the cage is straight. 3. An annular collar located at both ends in the axial direction;
A plurality of pillars that are arranged at equal intervals in the circumferential direction and extend in the axial direction to connect the flanges, and a plate-shaped material having a portion corresponding to the flanges and the pillars is annularly formed. 2. A needle roller bearing for a transmission according to claim 1, wherein the end is butt-welded and the inner diameter of the flange is larger than the inner diameter of the pillar to provide a step. 4. A needle for positioning a synchromesh device at one end of a transmission gear and for rotatably supporting the transmission gear on a rotating shaft in a transmission to which lubricating oil is supplied from the other end of the transmission gear. A roller bearing, comprising: a plurality of needle rollers interposed between a shaft and a transmission gear; and a cage for holding the needle rollers at equal intervals in a circumferential direction. A needle roller bearing for a transmission, wherein an outer diameter guide has a straight outer shape of a cage or a recessed step at a central portion of the outer diameter of the cage is suppressed to 15% or less of a roller diameter. 5. An annular collar located at both axial ends,
A plurality of pillars that are arranged at equal intervals in the circumferential direction and extend in the axial direction to connect the flanges, and a plate-shaped material having a portion corresponding to the flanges and the pillars is annularly formed. 5. The needle roller bearing for a transmission according to claim 4, wherein the end portion is butt-welded and the outer diameter of the flange portion is smaller than the outer diameter of the column portion to provide a step. . 6. The needle roller bearing for a transmission according to claim 5, wherein the step is 5 to 15% of a roller diameter.