JP2013117252A - Bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device having an improved durability, by configuring a cylindrical roller bearing to completely receive a radial load and by configuring a ball bearing to receive only an axial load.SOLUTION: An outer ring 11 of a ball bearing 2 is connected with an outer ring 21 of a cylindrical roller bearing 3 such that a relative displacement in a radial direction and a circumferential direction is possible, and a relative displacement in an axial direction is impossible. A rolling element arrangement groove 35 is arranged between both outer rings 11, 21, and a ball 8 for carrying load in a radial direction which is rollable in the radial direction and circumferential direction is disposed in the rolling element arrangement groove 35.

Description

  The present invention relates to a bearing device, and more particularly, to a bearing device in which a ball bearing and a cylindrical roller bearing are arranged with outer rings and inner rings adjacent to each other.

  As a bearing device, a ball bearing and a cylindrical roller bearing are arranged so that the outer rings and the inner rings are adjacent to each other. The ball bearings receive the axial load and the cylindrical roller bearing to receive the radial load. (Patent Document 1).

JP 2010-226927 A

  In the configuration shown in Patent Document 1, the ball bearing is a three-point or four-point contact so that it can receive a load in the axial direction, and this ball bearing has a radial load. When this occurs, there is a possibility that the life will be shortened by causing multiple hits.

  An object of the present invention is to provide a bearing device that has improved durability by allowing a cylindrical roller bearing to receive a radial load entirely and a ball bearing to receive only an axial load.

  A bearing device according to the present invention has a plurality of balls arranged between an outer ring, an inner ring, and both wheels, has a ball bearing that receives an axial load, and a plurality of rollers arranged between the outer ring, the inner ring, and both wheels, and is radial. In a bearing device provided with a cylindrical roller bearing that receives a load, and the ball bearing and the cylindrical roller bearing are arranged with the outer rings and the inner rings adjacent to each other, the outer ring of the ball bearing and the outer ring of the cylindrical roller bearing are: They are coupled by coupling means so that they can be moved relative to each other in the radial direction and the circumferential direction but not in the axial direction, and a rolling element disposition groove is provided between the outer rings. A rolling element capable of rolling in the radial direction and the circumferential direction is arranged in the moving body arranging groove.

  The movement of the outer ring of the ball bearing and the rolling element between the bearings is not restricted in the radial direction and the circumferential direction. Therefore, when a radial load is applied to the ball bearing, the rolling elements disposed between the outer rings of the bearing move in the radial direction, thereby preventing the ball bearing from receiving the radial load. As a result, the cylindrical roller bearing receives the entire radial load, and the ball bearing receives only the axial load, thereby improving the durability of the bearing device.

  The coupling means includes an L-shaped protrusion provided on one end face of the outer ring of the ball bearing and the outer ring of the cylindrical roller bearing, and an L-shaped protrusion provided on the other end face. An L-shaped engagement groove that opens radially outward, and the projecting portion includes a shaft portion extending in parallel to the axial direction and a bent portion extending in the circumferential direction from the tip of the shaft portion, The engaging groove extends inward in the axial direction from the end surface, has a first groove portion having a circumferential length equal to or greater than a circumferential length of the protruding portion, and extends in the circumferential direction continuously to the first groove portion. The second groove may have an axial length equal to the axial length of the bent portion.

  That is, if the radial movement of the outer ring of the ball bearing is restricted, a radial load may be transmitted between the bearings. Therefore, the outer ring of the ball bearing and the outer ring of the cylindrical roller bearing are relatively moved in the radial direction and the circumferential direction. However, it is necessary that the relative movement in the axial direction is impossible, and this is achieved by a simple configuration in which the L-shaped protrusion and the L-shaped engagement groove are fitted together.

  The rotation shaft supported by the ball bearing and the cylindrical roller bearing may be a pinion shaft.

  Since this pinion shaft is used in transmissions and the like, both radial load and axial load act on it, it is necessary for the bearing device to receive both of these loads. To apply the above bearing device, It is preferable.

  According to the bearing device of the present invention, the outer ring of the ball bearing and the outer ring of the cylindrical roller bearing are coupled by the coupling means so that the relative movement in the radial direction and the circumferential direction is possible and the relative movement in the axial direction is impossible. Since a rolling element arrangement groove is provided between the outer rings, and a rolling element that can roll in the radial direction and the circumferential direction is arranged in the rolling element arrangement groove, the ball bearing When a radial load is applied, the rolling elements between the bearings move in the radial direction, thereby preventing the ball bearing from receiving the radial load, thereby allowing the cylindrical roller bearing to receive the radial load entirely. The ball bearing receives only an axial load, and durability is improved.

FIG. 1 is a longitudinal sectional view showing an embodiment of a bearing device according to the present invention. FIG. 2 is a plan view of FIG. 1 viewed from the outside in the radial direction. 3A and 3B are diagrams showing the ball bearing and the cylindrical roller bearing separately, wherein FIG. 3A is a plan view viewed from the outside in the radial direction, and FIG. 3B is a longitudinal sectional view.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 3 show an embodiment of the bearing device of the present invention. In the following description, the left and right refer to the left and right in FIG.

  The bearing device (1) is used in a transmission or the like. As shown in FIG. 1, the ball bearing (2) and the cylindrical roller bearing (3) are arranged adjacent to each other in the left and right (axial direction). It consists of

  The ball bearing (2) has a plurality of balls (13) disposed between the outer ring (11), the inner ring (12), and both wheels (11) (12).

  The cylindrical roller bearing (3) has an outer ring (21), an inner ring (22), and a plurality of rollers (23) disposed between the two rings (21) and (22).

  The inner ring (12) of the ball bearing (2) and the inner ring (22) of the cylindrical roller bearing (3) are fitted into the rotating shaft (4) (press-fit). The rotating shaft (4) is formed with a step (4a) that receives the left end surface of the inner ring (12) of the ball bearing (2) disposed on the left side.

  The outer ring (11) of the ball bearing (2) and the outer ring (21) of the cylindrical roller bearing (3) are fitted in the housing (5). The housing (5) is formed with a step (5a) for receiving the right end surface of the outer ring (21) of the cylindrical roller bearing (3) disposed on the right side. Movement of the outer ring (11) to the left of the ball bearing (2) arranged on the left side is prevented by the retaining ring (6). The outer ring (11) of the ball bearing (2) must be capable of relative movement in the radial direction and the circumferential direction, so it is essential that the outer ring (11) is fitted in the housing (5). The outer ring (21) of the cylindrical roller bearing (3) is not limited to clearance fit.

  The rotating shaft (4) supported by the bearing device (1) is a pinion shaft having a pinion gear (4b) at the left end. Since both a radial load and an axial load act on the pinion shaft (4), the ball bearing (2) is in a 4-point contact so that it can receive the axial load. Can be received by the cylindrical roller bearing (3).

  Depending on mounting conditions and load conditions, a radial load may be applied to the ball bearing (2) that is in contact with four points. If this load is large, multiple points will occur and the ball bearing (2) will be durable. May be reduced.

  Therefore, the bearing device (1) is provided with a mechanism for releasing a radial load from acting on the ball bearing (2). Specifically, the outer ring (11) of the ball bearing (2) and the outer ring (21) of the cylindrical roller bearing (3) can be moved relative to each other in the radial direction and the circumferential direction, and relative movement in the axial direction is not possible. A coupling means (7) for coupling in a possible manner is provided, and balls (rolling elements) (8) for radial load bearing are disposed between the outer rings (11) and (21).

  The coupling means (7) is provided on the end surface of the outer ring (21) of the cylindrical roller bearing (3) and the L-shaped protrusion (31) provided on the end surface of the outer ring (11) of the ball bearing (2). And an L-shaped engaging groove (32) engaged with the L-shaped projecting portion (31). As shown in FIGS. 2 and 3, the L-shaped projecting portion (31) includes a shaft portion (31a) extending in parallel to the axial direction and a bent portion (31b) extending in the circumferential direction from the tip of the shaft portion (31a). ). The engagement groove (32) opens radially outward, extends axially inward from the end surface, and guides the protrusion (31). The first groove (32a) and the first groove (32a) And a second groove portion (32b) that extends in the circumferential direction and accommodates the bent portion (31a) of the protruding portion (31). The circumferential length of the first groove portion (32a) is made equal (or larger) to the circumferential length of the entire protrusion (31). The second groove portion (32b) is formed by enlarging the portion on the back side of the first groove portion (32a) (the portion located inward in the axial direction) in the circumferential direction, and its axial length is The axial length of the bent portion (31a) of the protruding portion (31) is made equal.

  In the state of FIG. 3, the outer ring (11) of the ball bearing (2) is moved in the axial direction and then rotated in the circumferential direction. Thereby, as shown in FIG. 2, the L-shaped protrusion (31) and the L-shaped engaging groove (32) are fitted together, and the outer ring (11) of the ball bearing (2) and the cylindrical roller bearing ( With respect to the outer ring (21) of 3), relative movement in the axial direction is impossible while relative movement in the radial direction and circumferential direction is possible.

  An annular recess (33) (34) is provided on the end face on the abutting side of each outer ring (11) (21), and the both recesses (33) (34) are joined together as shown in FIG. In addition, a rolling element arrangement groove (35) having a square cross section and an annular shape is formed. In the rolling element arranging groove (35), the radial load bearing ball (8) is arranged to roll. The radial load bearing balls (8) are held by the bottom surfaces of the recesses (33) and (34) of the outer rings (11) and (21) in the circumferential direction and diameter along the rolling element placement groove (35). Rollable in the direction.

  The movement of the outer ring (11) of the ball bearing (2) and the radial load bearing ball (8) is not restricted in the radial and circumferential directions, and a radial load was applied to the ball bearing (2). At this time, the ball bearing (2) is prevented from receiving a radial load by moving the radial load bearing ball (8) in the radial direction. As a result, the cylindrical roller bearing (3) receives the entire radial load, and the ball bearing (2) receives only the axial load, thereby improving the durability of the bearing device (1). In addition, if the radial movement of the outer ring (11) of the ball bearing (2) is restricted, a radial load may be transmitted between the bearings, so as described above, as described above, the outer ring (11) of the ball bearing (2) And the outer ring (21) of the cylindrical roller bearing (3) can be relatively moved in the radial direction and the circumferential direction by the coupling means (7), and cannot be relatively moved in the axial direction.

  In the above description, the ball bearing (2) is four-point contact, but may be three-point contact. That is, the three-point contact ball bearing, like the four-point contact, can receive an axial load, and if it receives a radial load, the durability may decrease. In combination with the above-mentioned coupling means (7) and the radial load bearing ball (8) between the outer rings (11) and (21), the durability can be improved. it can.

  In the above, the annular recess (33) (34) is provided in any one of the outer rings (11) (21), and by increasing the depth of this recess, only one of the recesses, You may make it form the groove | channel for rolling element arrangement | positioning.

  Further, the radial load bearing balls (8) need only be movable in the circumferential direction and the radial direction, so they are provided at predetermined intervals in the circumferential direction instead of the annular rolling element arranging grooves (35). A plurality of (at least three) pocket-shaped rolling element arrangement grooves are formed, and balls (rolling elements) are arranged in the rolling element arrangement grooves so as to be movable in the circumferential direction and the radial direction. Also good. Furthermore, the radial load bearing ball (8) is disposed only between the outer ring (11) of the ball bearing (2) and the outer ring (21) of the cylindrical roller bearing (3). If the surface opposite the cylindrical roller bearing (3) of the outer ring (11) of 2) is in contact with the housing or spacer, for example, the outer ring (11) of the ball bearing (2) A radial load bearing ball may be arranged on the surface opposite to the cylindrical roller bearing (3).

(1): Bearing device, (2): Ball bearing, (3): Cylindrical roller bearing, (8): Ball for rolling load in the radial direction (rolling element), (11): Outer ring, (12): Inner ring, (13): Ball, (21): Outer ring, (22): Inner ring, (23): Roller, (31): Projection, (32): Engagement groove, (35): Groove for rolling element arrangement

Claims (3)

  A ball bearing having a plurality of balls arranged between the outer ring, the inner ring and both wheels and receiving an axial load; and a cylindrical roller bearing having a plurality of rollers arranged between the outer ring, the inner ring and both wheels and receiving a radial load; In the bearing device in which the ball bearing and the cylindrical roller bearing are arranged so that the outer rings and the inner rings are adjacent to each other, the outer ring of the ball bearing and the outer ring of the cylindrical roller bearing are in the radial direction and the circumferential direction. It is coupled by coupling means so that relative movement is possible and relative movement in the axial direction is impossible, and a rolling element arranging groove is provided between both outer rings, and in the rolling element arranging groove, A bearing device in which rolling elements capable of rolling in a radial direction and a circumferential direction are arranged.   The coupling means includes an L-shaped protrusion provided on one end face of the outer ring of the ball bearing and the outer ring of the cylindrical roller bearing, and an L-shaped protrusion provided on the other end face. An L-shaped engagement groove that opens radially outward, and the projecting portion includes a shaft portion extending in parallel to the axial direction and a bent portion extending in the circumferential direction from the tip of the shaft portion, The engaging groove extends inward in the axial direction from the end surface, has a first groove portion having a circumferential length equal to or greater than a circumferential length of the protruding portion, and extends in the circumferential direction continuously to the first groove portion. The bearing device according to claim 1, comprising a second groove portion having an axial length equal to an axial length of the bent portion.   3. The bearing device according to claim 1, wherein the rotary shaft supported by the ball bearing and the cylindrical roller bearing is a pinion shaft.

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