JP2015117770A - Bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device in which a helical gear is relatively rotatably and externally fit to an outside diameter side of a shaft via a radial needle roller bearing, oil is radially and outwardly supplied to an intermediate portion of the needle roller bearing in an axial direction from an oil passage formed in the shaft, and when the helical gear is inclined, it is preferable that the oil is supplied to a side at which the contact surface pressure of a needle roller with respect to the shaft becomes large (side on which a thrust load is applied).SOLUTION: An inside diameter dimension R1 of a region 20 at a side on which a thrust load acts accompanied by the rotation of a helical gear 3 at an internal diameter face of a cage 6 of a needle roller bearing 5 is set larger than an inside diameter dimension R2 of a region 30 at a side opposite to the region.

Description

  According to the present invention, a helical gear is externally rotatably mounted on the outer diameter side of a shaft via a radial needle roller bearing, and an oil passage provided in the shaft extends from an axial direction of the needle roller bearing. The present invention relates to a bearing device in which oil is supplied radially outward.

  For example, as shown in Patent Document 1, in a synchromesh mechanism of a manual transmission, a gear, a synchro hub, or the like is disposed on the outer diameter side of a shaft that is rotatably supported by a case via a radial ball bearing. Are armored side by side in the axial direction.

  The gear is rotatably attached to the outer diameter side of the shaft via a radial needle roller bearing, and the synchro hub is integrally attached to the outer diameter side of the shaft. The inner diameter of the cage of the needle roller bearing is constant over the entire length in the axial direction.

Japanese Patent Laid-Open No. 11-013752

  In Patent Document 1, when the gear is a helical gear, for example, the helical gear generates a thrust load in one axial direction, that is, in the direction toward the ball bearing, as the helical gear meshes with the helical gear that meshes with the helical gear. To do. As a result, the helical gear may be inclined, for example, toward the ball bearing side, and the contact surface pressure on one end side in the axial direction of the needle roller of the needle roller bearing on the inner diameter side of the helical gear is increased. In the cage of the tapered roller bearing, the edge near the ball bearing may approach the outer peripheral surface of the shaft, and the radial clearance may be reduced.

  In such a case, for example, when the oil is supplied radially outward from the center of the shaft toward the needle roller bearing, the portion where the radial clearance becomes smaller obstructs the flow of oil. Therefore, the oil supply to the contact portion between the needle roller and the shaft where the contact surface pressure increases and the ball bearing side may be insufficient.

  In view of such circumstances, the present invention provides the needle roller from an oil passage in which a helical gear is externally rotatably mounted on the outer diameter side of the shaft via a radial needle roller bearing and provided inside the shaft. In a bearing device in which oil is supplied radially outwardly to an axially intermediate portion of the bearing, the contact surface pressure of the needle roller against the shaft increases when the helical gear is tilted (the side on which a thrust load acts) The purpose is to improve the oil supply to).

  According to the present invention, a helical gear is externally rotatably mounted on the outer diameter side of a shaft via a radial needle roller bearing, and an oil passage provided in the shaft extends from an axial direction of the needle roller bearing. A bearing device in which oil is supplied radially outwardly, and an inner diameter dimension of a region on a working side of a thrust load generated by the rotation of the helical gear on an inner diameter surface of the retainer of the needle roller bearing is opposite to It is characterized by being set to be larger than the inner diameter dimension of the side region.

  In this configuration, when the helical gear is tilted by the thrust load, the contact surface pressure on one end side in the axial direction of the needle roller increases.

  In addition, although the area on the side on which the thrust load acts on the retainer approaches the outer peripheral surface of the shaft with the inclination, the radial gap is reduced, but the radial gap is a conventional example ( Compared to a configuration in which the inner diameter of the cage is constant in the entire axial direction). On the other hand, the radial clearance between the region opposite to the region on which the thrust load acts and the outer peripheral surface of the shaft increase with the inclination, but the radial clearance is retained. Since the inner diameter dimension of the cage is set to be small, the radial gap can be made substantially the same as in the conventional example (the configuration in which the inner diameter dimension of the cage is constant in the entire axial direction).

  For this reason, the oil supplied from the oil passage to the needle roller bearing is diverted well in both axial directions from the axial intermediate portion of the retainer of the needle roller bearing. That is, even when the helical gear is tilted, oil is satisfactorily supplied also to the region on the working side of the thrust load in the cage, so that the contact between the roller and the shaft that increases the contact surface pressure. The lubrication of the contact part and the oil supply to the lubrication-needed member arranged on this side are improved.

  According to the present invention, a helical gear is externally rotatably mounted on the outer diameter side of a shaft via a radial needle roller bearing, and an oil passage provided in the shaft extends from an axial direction of the needle roller bearing. In a bearing device in which oil is supplied radially outward, the oil supply to the side where the contact surface pressure of the needle roller with respect to the shaft increases when the helical gear tilts (the side on which the thrust load acts) is excellent. It becomes possible.

It is sectional drawing which shows the upper half of one Embodiment of the bearing apparatus which concerns on this invention. It is a figure which expands and shows only the needle roller bearing of FIG. FIG. 3 is a cross-sectional view taken along line (3)-(3) in FIG. 2. FIG. 3 is a cross-sectional view taken along line (3)-(3) in FIG. 2. It is explanatory drawing which shows a state when a helical gear inclines in FIG. It is a figure corresponding to Drawing 1 in other embodiments of a needle roller bearing with which a bearing device concerning the present invention is provided. It is an arrow view of the (7)-(7) line cross section of FIG. FIG. 7 is a cross sectional view taken along line (8)-(8) in FIG. 6. It is explanatory drawing which shows a state when a helical gear inclines in FIG.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the accompanying drawings.

  1 to 5 show an embodiment of the present invention. In this embodiment, a bearing device used in a synchromesh mechanism of a manual transmission is taken as an example.

  In the figure, 1 is a shaft, and this shaft 1 is rotatably supported by a transmission case (not shown) via a radial ball bearing 2. The ball bearing 2 is a “deep groove ball bearing” capable of receiving a thrust load.

  On the outer diameter side of the shaft 1, the helical gear 3 and the synchro hub 4 are arranged adjacent to each other in the axial direction on one side of the ball bearing 2 in the axial direction.

  The helical gear 3 is rotatably attached to a region between the sync hub 4 and the ball bearing 2 on the outer diameter side of the shaft 1 via a radial needle roller bearing 5.

  The synchro hub 4 is attached so that it can rotate integrally and can be displaced in the axial direction by, for example, spline fitting. The synchro hub 4 is restricted from being displaced in one axial direction by a gear (not shown) disposed on one axial side thereof.

  As described above, the helical gear 3 is sandwiched between the ball bearing 2 and the synchro hub 4 from both sides in the axial direction via a predetermined gap, so that the displacement of the helical gear 3 in both the axial directions is restricted. .

  In this embodiment, the needle roller bearing 5 has a configuration in which a number of needle rollers 7 are held in a non-separated state in a cage 6 and does not have an inner ring and an outer ring. This type of needle roller bearing 5 is generally called “cage and roller”.

  An oil passage 8 for supplying oil to the axial intermediate portion of the needle roller bearing 5 is provided inside the shaft 1. The oil passage 8 has a main passage portion along the central axis 100 of the shaft 1 and a branch passage portion that is opened on the outer peripheral surface of the shaft 1 radially outward from several circumferential positions of the main passage portion. doing.

  The oil supplied to the oil passage 8 is discharged radially outward from the branch passage portion as indicated by an arrow in FIG. 1, but is released into the arrangement space of the needle roller bearing 5. Is diverted in both axial directions, passes through the inside of the needle roller bearing 5 and is supplied to the synchro hub 4 side and the ball bearing 2 side.

  Next, the configuration of the cage 6 of the needle roller bearing 5 will be described in detail with reference to FIGS.

  The cage 6 is made of a synthetic resin (for example, a polyamide resin) or a metal, and has a two-piece structure in which a cylindrical member is halved.

  The pair of retainers 6 are attached to the outer peripheral surface of the shaft 1 in such a form that they are tangled from the radially outer diameter side. A through-hole (also referred to as a pocket) 6 a for holding the needle rollers 7 is provided for each constant pitch in the circumferential direction of the pair of cages 6. The through-hole 6a has a long rectangle along the axial direction when viewed from the outer diameter side.

  In this embodiment, in the cage 6 of the needle roller bearing 5, the thickness (radial direction) dimension H1 of the region 20 on one end side in the axial direction is thinner than the thickness (radial direction) size H2 of the region 30 on the other end side in the axial direction. Thus, the inner diameter R1 of the axial one end side region 20 is set to be larger than the inner diameter R2 of the axial other end side region 30 on the inner diameter surface of the cage 6. Hereinafter, the axial one end side region 20 is referred to as a “thin region”, and the axial other end region 30 is referred to as a “thick region”.

  The cage 6 is configured such that the thin region 20 is positioned on the side where the thrust load generated by the rotation of the helical gear 3 acts, that is, near the ball bearing 2, and the thick region 30 is positioned near the sync hub 4. Placed in.

  Further, in this embodiment, the radial center Q of the thick region 30 of the cage 6 is offset to the outer diameter side by a predetermined dimension X from the circle (pitch circle: PC) connecting the centers of many needle rollers 7. It has come to be. As a result, the cage 6 is “outer diameter guide” in which the cage 6 is guided by the inner peripheral surface of the helical gear 3.

  Furthermore, in this embodiment, as shown in FIG. 3, the circumferential width of the region existing in the thin region 20 of the cage 6 in the through-hole 6a gradually decreases from the inner diameter side toward the outer diameter side. In the through hole 6a, the opening width W1 in the circumferential direction on the outer diameter side of the region existing in the thin region 20 of the cage 6 is set to be smaller than the diameter dimension r of the needle roller 7. This prevents the needle rollers 7 from coming out radially outward from the through hole 6a.

  As shown in FIGS. 3 and 4, the circumferential width of the region existing in the thick region 30 of the cage 6 in the through hole 6a is gradually increased from the inner diameter side toward the radial center, In the through hole 6 a, the opening width W <b> 2 in the circumferential direction on the inner diameter side of the region existing in the thick region 30 of the cage 6 is set smaller than the diameter dimension r of the needle roller 7. Thereby, the needle rollers 7 are prevented from coming out radially inward from the through holes 6a. In the through hole 6a, the circumferential width of the region existing in the thick region 30 of the cage 6 gradually decreases from the radial center to the outer diameter side.

  Here, in the case of the structure shown in FIG. 1, the thrust load in the axial direction of the helical gear 3 toward the ball bearing 2, for example, in accordance with the meshing of the helical gear 3 and the helical gear (not shown) that meshes with the helical gear 3. Therefore, as shown by the arrow in FIG. 5, the helical gear 3 may be inclined toward the ball bearing 2, for example. In FIG. 5, the inclination of the helical gear 3 is exaggerated.

  In this case, the contact surface pressure between the shaft 1 and the axial end of the needle roller 7 of the needle roller bearing 5 on the inner diameter side of the helical gear 3 (the side on which the thrust load acts) increases.

  Furthermore, although one axial end side (thrust load acting side) of the cage 6 approaches the outer peripheral surface of the shaft 1 and the radial gap between the two becomes smaller, the radial gap is smaller than the conventional example (the inner diameter of the cage). Compared to a configuration in which the dimensions are constant in the entire axial direction). On the other hand, in the cage 6 of the needle roller bearing 5, the radial clearance between the other axial end (opposite to the thrust load acting side) and the outer peripheral surface of the shaft 1 is increased. Since the gap is set to be small by reducing the inner diameter dimension R2 of the cage 6, the radial gap is substantially the same as the conventional example (the configuration in which the inner diameter dimension of the cage is constant in the entire axial direction). Can be.

  For this reason, the oil supplied from the oil passage 8 to the needle roller bearing 5 is diverted well in both axial directions from the axially intermediate portion of the retainer 6 of the needle roller bearing 5. . That is, even when the helical gear 3 is tilted, the oil is satisfactorily supplied to both the thin region 20 and the thick region 30 in the cage 6 of the needle roller bearing 5, so that the contact surface pressure is large. Thus, the lubrication of the contact portion between the needle roller 7 and the shaft 1 and the oil supply to the ball bearing 2 (member requiring lubrication) arranged on this side are improved.

  As described above, in the embodiment to which the present invention is applied, the oil supplied to the inner diameter side of the axial intermediate portion of the radial needle roller bearing 5 even when the helical gear 3 is tilted in the acting direction of the thrust load. Has been devised so that it can be easily diverted in both axial directions.

  That is, in the bearing device according to the present invention, even when the helical gear 3 is tilted, the oil supplied from the oil passage 8 to the needle roller bearing 5 is thinned from the axially intermediate portion of the cage 6 of the needle roller bearing 5. Good supply is provided to both the region 20 and the thick region 30.

  Therefore, according to the bearing device according to the present invention, the region where the contact surface pressure between the needle roller 7 and the shaft 1 of the needle roller bearing 5 increases can be prevented from being prematurely worn or seized. It will be possible to contribute to the improvement of performance.

  In addition, this invention is not limited only to the said embodiment, It can change suitably in the range equivalent to the claim and the said range.

  (1) In the above embodiment, the bearing device used for the synchromesh mechanism of the manual transmission is given as an example. However, the present invention is not limited to this, and the bearing device used for the so-called gear transmission device in general. Is possible.

  (2) In the above embodiment, an example is given in which the region on one end side in the axial direction in the cage 6 of the needle roller bearing 5 is the thin region 20 and the region on the other end side in the axial direction is the thick region 30. The present invention is not limited to this.

  For example, as shown in FIG. 6 to FIG. 9, the cage (thickness direction) is made constant over the entire length in the axial direction and then bent so as to project radially inward in the region on the other end side in the axial direction. By providing the bent portion 40, it is possible to set the inner diameter R3 of the region on the one end side in the axial direction (non-bent region 50) larger than the inner diameter R4 of the bent portion 40.

  In this embodiment, the radial center Q of the cage 6 is offset to the outer diameter side by a predetermined dimension X from the circle (pitch circle: PC) connecting the centers of the many needle rollers 7. . As a result, the cage 6 is “outer diameter guide” in which the cage 6 is guided by the inner peripheral surface of the helical gear 3.

  Further, in this embodiment, as shown in FIG. 7, the width in the circumferential direction of the region existing in the non-bending region 50 of the cage 6 in the through hole 6a is gradually reduced from the inner diameter side toward the outer diameter side. Thus, the opening width W3 in the circumferential direction on the outer diameter side of the region where the non-bending region 50 of the cage 6 exists in the through hole 6a is set to be smaller than the diameter dimension r of the needle roller 7. This prevents the needle rollers 7 from coming out radially outward from the through hole 6a.

  Further, as shown in FIGS. 7 and 8, the circumferential width of the region where the bent portion 40 of the cage 6 exists in the through hole 6a gradually increases from the inner diameter side toward the outer diameter side, The opening width W4 in the circumferential direction on the inner diameter side of the region where the bent portion 40 of the cage 6 exists in the through hole 6a is set smaller than the diameter dimension r of the needle roller 7. Thereby, the needle rollers 7 are prevented from coming out radially inward from the through holes 6a.

  In the case of this embodiment as well, as in the above embodiment, even when the helical gear 3 is tilted in the direction of the thrust load, as shown by the arrows in FIG. As a result, the region where the contact surface pressure between the needle roller 7 and the shaft 1 of the needle roller bearing 5 becomes large is worn out or seized at an early stage. Will be able to contribute to improved durability.

  According to the present invention, a helical gear is externally rotatably mounted on the outer diameter side of a shaft via a radial needle roller bearing, and an oil passage provided in the shaft extends from an axial direction of the needle roller bearing. It can be suitably used for a bearing device in which oil is supplied radially outward.

1 axis
2 Radial ball bearings
3 Helical gear
5 Radial needle roller bearings
6 cage
6a Through hole for holding needle rollers of cage
7 Needle roller
8 Oil passage 20 Thin area near one end of cage in axial direction 30 Thick area near the other axial end of cage H1 Thickness of thin area H2 Thickness of thick area R1 Inner diameter of thin area R2 Thick area Inner diameter of

Claims (1)

A helical gear is externally rotatably mounted on the outer diameter side of the shaft via a radial needle roller bearing, and oil is radially directed from an oil passage provided inside the shaft to an intermediate portion in the axial direction of the needle roller bearing. A bearing device supplied outwardly,
The inner diameter dimension of the working side of the thrust load generated by the rotation of the helical gear on the inner diameter surface of the cage of the needle roller bearing is set larger than the inner diameter dimension of the opposite area. A bearing device.

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