JP2015183696A - bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing capable of comparatively facilitating assembling, suppressing the falling of a rotation shaft, and decreasing size.SOLUTION: First transmission grooves abutting on a rolling body 15a in a first row are provided on both of an outer ring 11 and an inner ring 14. The outer ring 11 is provided with the first transmission groove 12a, and the inner ring 14 is provided with the first transmission groove 12b. A second transmission groove 13b abutting on a rolling body 15b in a second row is provided only on the inner ring 14. The rolling body 15a in the first row abuts on the first transmission groove 12a of the outer ring 11 and the first transmission groove 12b of the inner ring 14, and the rolling body 15b in the second row abuts on the second transmission groove 13b of the inner ring 14 and a flat portion 16 of the outer ring 11.

Description

  The present invention relates to a bearing that has two rows of rolling elements and prevents the shaft from collapsing.

  There are single row bearings and double row bearings. The rotation shaft support by the bearing is for smooth rotation of the rotation shaft. To support the rotation shaft having a certain width against the radial load, in order to suppress the shaft collapse of the rotation shaft, 2 Often single row bearings are used. Further, a double row bearing having two rows of rolling elements may be used (for example, see Patent Document 1).

JP 2013-96473 A

  However, if two single row bearings are used for a rotating shaft with a certain width to prevent the shaft from collapsing, a width space for arranging two single row bearings in parallel is required. It is difficult to save space.

  In addition, since the double row bearing has two rows of rolling elements, two transfer grooves that contact the two rows of rolling elements are formed in the outer ring and the inner ring. Matching the diameters of the moving bodies is necessary, and assembly is very difficult.

  FIG. 4 is an explanatory view of a conventional double row bearing assembly procedure, and FIG. 4 (a) is a sectional view of an outer ring and an inner ring in a state where the first row rolling elements and the second row rolling elements are not mounted. 4B is a cross-sectional view in which the first row of rolling elements are mounted, and FIG. 4C is a cross-sectional view in which the first row of rolling elements and the second row of rolling elements are mounted.

  First, the outer ring and inner ring of the double row bearing will be described. As shown in FIG. 4A, a first transfer groove 12a that contacts the first row of rolling elements and a second transfer groove 13a that contacts the second row of rolling elements are formed on the inner surface of the outer ring 11. Yes. A first transfer groove 12b that faces the first transfer groove 12a of the outer ring 11 and contacts the first row of rolling elements is formed on the outer surface of the inner ring 14, and faces the second transfer groove 13a of the outer ring 11. A second transfer groove 13b is formed in contact with the second row of rolling elements. The outer ring 11 is fixed to a member to which a bearing is attached, and the inner ring 14 is fixed to a rotating shaft.

  In such a double row bearing, it is necessary to match the diameters of the rolling elements for each of the first transfer groove 12a and the first transfer groove 12b, and the first transfer groove 12a of the outer ring 11 and the first of the inner ring 14 that face each other. Since the positional accuracy in the rotation axis direction of the transfer groove 12b, the second transfer groove 13a of the outer ring 11 and the second transfer groove 13b of the inner ring 14 is also supplied, manufacturing accuracy of the outer ring 11 and the inner ring 14 is required. Furthermore, double row bearings are very difficult to assemble.

  An example of the work of mounting the first row of rolling elements 15a and the second row of rolling elements 15b from the state in which the first row of rolling elements 15a and the second row of rolling elements 15b shown in FIG. Will be explained. FIG. 5 is an explanatory diagram of an example of an assembly operation for bringing the first row of rolling elements 15a into contact with the first transfer grooves 12a and 12b. The inner ring 14 is arranged eccentrically in the outer ring 11, a first row of rolling elements 15a is inserted between the outer ring 11 and the inner ring 14, and a narrow space between the outer ring 11 and the inner ring 14 as indicated by an arrow. The rolling elements 15a are pushed into the first transfer grooves 12a and 12b in order. As a result, as shown in FIG. 4B, the first row of rolling elements 15a is mounted in the first transfer grooves 12a and 12b.

  However, when assembling the second row of rolling elements 15b in contact with the second transfer grooves 13a and 13b, as shown in FIG. 4B, the first row of rolling elements 15a is already in the first transfer groove. Since they are in contact with 12a and 12b, the inner ring 14 cannot be arranged eccentrically in the outer ring 11. Therefore, after bringing the first row of rolling elements 15a into contact with the first transfer grooves 12a and 12b, the assembly operation shown in FIG. 5 is adopted, and the second row of rolling elements 15b is replaced with the second transfer grooves 13a and 13b. Cannot be easily brought into contact.

  If the assembly work shown in FIG. 5 is adopted and the first row of rolling elements 15a and the second row of rolling elements 15b are brought into contact with each other, the inner ring 14 is arranged eccentrically in the outer ring 11, and the outer ring The first row of rolling elements 15a and the second row of rolling elements 15b are simultaneously inserted between 11 and the inner ring 14. Then, the first row of rolling elements 15a and the second row of rolling elements 15b are identified and sequentially brought into contact with the first transfer grooves 12a and 12b and the second transfer grooves 13a and 13b, as shown in FIG. As shown, since the first row of rolling elements and the second row of rolling elements must be mounted, assembly is very difficult and the cost is increased.

  An object of the present invention is to provide a bearing that is relatively easy to assemble and that can prevent the shaft from collapsing and can be downsized.

  The bearing of the present invention is formed in a cylindrical shape, and the inner surface has a flat portion having a constant axial diameter, and the flat portion is formed with an arc-shaped first transfer groove that contacts the first row of rolling elements. The second row of rolling elements are the outer ring that comes into contact with the flat portion, the flat outer surface that is cylindrical and has a constant axial diameter, and the outer surface has a smaller axial diameter toward the end of the outer surface. The flat portion is formed with an arc-shaped first transfer groove that comes into contact with the first row of rolling elements, and the inclined portion comes into contact with the second row of rolling elements. An inner ring in which a transfer groove is formed, a retainer for holding a first row of rolling elements in contact with the first transfer groove, and two rows from the second transfer groove provided in the end direction of the second transfer groove A separation preventing portion for preventing the first rolling element from separating, a first row of rolling elements provided at both ends of the outer ring and the inner ring, and A space for accommodating the rolling elements of Me column is characterized in that a plate forming together with the outer ring and the inner ring.

  According to the present invention, the first transfer groove that contacts the first row of rolling elements is provided on both the outer ring and the inner ring, and the second transfer groove that contacts the second row of rolling elements is provided only on the inner ring. The second rolling element comes into contact with the first transfer groove of the outer ring and the inner ring, and the second row of rolling elements comes into contact with the second transfer groove of the inner ring and the flat part of the outer ring, so that the second row of rolling elements can be easily assembled. Since the first row of rolling elements and the second row of rolling elements are provided, it is possible to suppress the axis of the rotating shaft from falling down. Further, the size can be reduced as compared with the case where two single row bearings are arranged in parallel.

Sectional drawing of the bearing which concerns on embodiment of this invention. Explanatory drawing of the assembly procedure of the bearing which concerns on embodiment of this invention. The side view of Drawing 2 (c). Explanatory drawing of the assembly procedure of the conventional double row bearing. Explanatory drawing of an example of the assembly operation which contacts the 1st row rolling element to the 1st transfer groove.

  Embodiments of the present invention will be described below. FIG. 1 is a sectional view of a bearing according to an embodiment of the present invention. The outer ring 11 is formed in a cylindrical shape, and the inner surface has a flat portion 16 having a constant axial diameter. The flat portion 16 is provided with a first transfer groove 12a that contacts the first row of rolling elements 15a. Yes. The first transfer groove 12a has a circular cross section. The inner ring 14 is formed in a cylindrical shape, and the outer surface has a flat portion 17 having a constant axial diameter and an inclined portion 18 in which the outer surface diameter decreases in the axial direction toward the end of the outer surface. An arc-shaped first transfer groove 12b that contacts the first row of rolling elements 15a is formed in the flat portion 17 on the outer surface of the inner ring 14, and an arc-shaped first contact groove 12b that contacts the second row of rolling elements 15b is formed on the inclined portion 18. A second transfer groove 13b is formed. In the direction of the end of the second transfer groove 13b, a detachment preventing portion for preventing the second row of rolling elements 15b from detaching from the second transfer groove 13b is provided. The separation preventing unit will be described later.

  Next, the first row of rolling elements 15 a and the second row of rolling elements 15 b are balls, and the first row of rolling elements 15 a that are in contact with the first transfer grooves 12 a and 12 b are kept at a constant distance by the retainer 19. Held. In addition, plates 20 are provided at both ends of the outer ring 11 and the inner ring 14, and together with the outer ring 11 and the inner ring 14, a space for accommodating the first row of rolling elements 15 a and the second row of rolling elements 15 b is formed. The outer ring 11 is fixed to a member to which a bearing is attached, and the inner ring 14 is fixed to a rotating shaft.

  FIG. 2 is an explanatory view of a bearing assembling procedure according to the embodiment of the present invention, and FIG. 2 (a) shows the outer ring and the inner ring in a state where the first row rolling elements and the second row rolling elements are not mounted. FIG. 2B is a sectional view in which the first row of rolling elements are mounted, and FIG. 2C is a sectional view in which the first row of rolling elements and the second row of rolling elements are mounted.

  As shown in FIG. 2A, the inner surface of the outer ring 11 has a flat portion 16 having a constant axial diameter. Then, an arc-shaped first transfer groove 12 a that abuts against the first row of rolling elements 15 a is provided in the circumferential direction of the flat portion 16. The outer surface of the inner ring 14 includes a flat portion 17 having a constant axial diameter and an inclined portion 18 in which the diameter of the outer surface decreases in the axial direction toward the end of the outer surface. The flat portion 17 is provided with an arc-shaped first transfer groove 12b facing the first transfer groove 12a of the outer ring 11 and contacting the first row of rolling elements 15a in the circumferential direction. The inclined portion 18 is provided with an arc-shaped second transfer groove 13b in contact with the second row of rolling elements 15b in the circumferential direction. In the direction of the end of the second transfer groove 13b, a separation preventing portion 21 is provided to prevent the second row of rolling elements 15b in contact with the second transfer groove 13b from separating from the second transfer groove 13b. Yes.

  The separation preventing portion 21 is provided such that the arc edge portion in the direction of the end of the outer surface of the inner ring 14 is slightly higher than the arc bottom portion of the second transfer groove 13b. The height of the separation preventing portion 21 is high enough to be pushed into the second transfer groove 13b when the second row of rolling elements 15b are brought into contact with the second transfer groove 13b. When the moving body 15b comes into contact with the second transfer groove 13b, the height is high enough to prevent the second row of rolling elements 15b in contact with the second transfer groove 13b from being separated from the second transfer groove 13b.

  Next, from the state where the first row of rolling elements 15a and the second row of rolling elements 15b shown in FIG. 2A are not mounted, the first row of rolling elements 15a and the second row of rolling elements 15b are mounted. The work procedure will be described. First, the first row of rolling elements 15 a are brought into contact with the first transfer groove 12 a of the outer ring 11 and the second transfer groove 12 b of the inner ring 14. As in the case of the conventional example shown in FIG. 5, this work is performed by placing the inner ring 14 eccentrically in the outer ring 11, inserting the first row of rolling elements 15 a between the outer ring 11 and the inner ring 14, As indicated by the arrows, the rolling element 15a is pushed into a narrow space between the outer ring 11 and the inner ring 14 and sequentially brought into contact with the first transfer grooves 12a and 12b. As a result, as shown in FIG. 2B, the first row of rolling elements 15a is mounted in the first transfer grooves 12a and 12b.

  Next, in order to mount the second row of rolling elements 15b from the state where the first row of rolling elements 15a shown in FIG. 2B is mounted in the first transfer grooves 12a and 12b, the second row of rolling elements 15a is mounted. The moving body 15b is sequentially pushed into the second transfer groove 13b of the inner ring 14. In this case, the second row of rolling elements 15b are guided by the inclined portion 18 on the outer surface of the inner ring 14 and come into contact with the second transfer groove 13b. On the other hand, since the second transfer groove is not provided in the outer ring 11, when the second row of rolling elements 15b comes into contact with the second transfer groove 13b, the second row of rolling elements is the flat portion of the outer ring 11 at that position. 16 abuts. As a result, as shown in FIG. 2C, the first row of rolling elements 15a and the second row of rolling elements 15b are mounted.

  3 is a side view of FIG. 2 (c), FIG. 3 (a) is a right side view, and FIG. 3 (b) is a left side view. In FIG. 3A, the first row of rolling elements 15 a that are in contact with the first transfer grooves 12 a and 12 b are held by the retainer 19 at a constant interval. In addition, illustration of the retainer 19 is abbreviate | omitted in FIG.2 (c).

  On the other hand, the second row of rolling elements 15b are mounted so as to form a full ball bearing between the outer ring 11 and the inner ring 14 as shown in FIG. The second transfer groove 13b is formed so that the second row of rolling elements 15b are arranged close to each other, and the size of the second row of rolling elements 15b is also in contact with the second transfer groove 13b. It is a size that is sometimes placed close together. The second row of rolling elements 15b is shown in FIG. 3 (b) in the case where a full ball bearing is formed. However, the second row of rolling elements 15b may be held by the retainer 19 at a constant interval. Good.

  Thus, the bearing of the embodiment of the present invention basically takes the form of a double row bearing, but the transfer groove is one row of the first transfer grooves 12a and 12b of the first row of rolling elements 15a. The rolling elements 15b in the second row are only the second transfer grooves 13b provided in the inner ring 14, and the second transfer grooves are not provided in the outer ring 11. Thereby, the matching of the diameters of the rolling elements 15b in the second row with respect to the second transfer grooves 13b becomes unnecessary, and the number of assembling steps can be reduced. Moreover, since it takes the form of a double-row bearing, the shaft collapse can be suppressed to some extent with one bearing according to the embodiment of the present invention, and space can be saved as compared with the case where two single-row bearings are used.

  In the above description, the inclined portion 18 is provided on the outer surface of the inner ring 14, and the arc-shaped second transfer groove 13 b with which the second row of rolling elements 15 b abut is provided on the inclined portion 18, but instead of the inner ring 14, An inclined portion 18 may be provided on the inner surface of the outer ring 11, and an arc-shaped second transfer groove 13b with which the second row of rolling elements 15b abut may be provided on the inclined portion 18.

  That is, the inner surface of the outer ring 11 formed in a cylindrical shape is provided with a flat portion 17 having a constant axial diameter and an inclined portion 18 in which the diameter of the outer surface decreases toward the end of the outer surface. An arc-shaped first transfer groove 12a that contacts the first row of rolling elements 15a is formed in the portion 17, and an arc-shaped second transfer groove 13 that contacts the second row of rolling elements is formed in the inclined portion. . On the other hand, a flat portion 16 having a constant axial diameter is provided on the outer surface of the cylindrical inner ring 14, and the flat portion 16 faces the first transfer groove 12 a provided on the inner surface of the outer ring 11. An arc-shaped first transfer groove 12b that contacts the first row of rolling elements 15a is formed, and the second row of rolling elements 15b is formed so as to contact the flat portion 16. In this case, the same effect can be obtained.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 11 ... Outer ring, 12 ... 1st transfer groove, 13 ... 2nd transfer groove, 14 ... Inner ring, 15a ... Rolling body of 1st row, 15b ... Rolling body of 2nd row, 16 ... Flat part, 17 ... Flat part, 18 ... Inclined part, 19 ... Retainer, 20 ... Plate, 21 ... Detachment prevention part

Claims (2)

The cylindrical inner surface has a flat portion with a constant axial diameter, and the flat portion is formed with an arc-shaped first transfer groove that contacts the first row of rolling elements, and the second row of rolling elements. Is an outer ring that comes into contact with the flat part,
The outer surface has a flat portion having a constant axial diameter and an inclined portion in which the outer surface has a smaller axial diameter toward the end of the outer surface. An inner ring in which an arc-shaped first transfer groove that contacts the moving body is formed and an arc-shaped second transfer groove that contacts the second row of rolling elements is formed in the inclined portion;
A retainer for holding a first row of rolling elements in contact with the first transfer groove;
A detachment preventing portion provided in the end portion direction of the second transfer groove and preventing the second row of rolling elements from detaching from the second transfer groove;
A bearing comprising: a plate which is provided at both ends of the outer ring and the inner ring and which forms a space for accommodating the first row of rolling elements and the second row of rolling elements together with the outer ring and the inner ring. The inner surface has a flat portion having a constant axial diameter and an inclined portion in which the outer surface has a smaller axial diameter toward the end of the outer surface. An outer ring in which an arc-shaped first transfer groove that contacts the moving body is formed and an arc-shaped second transfer groove that contacts the second row of rolling elements is formed in the inclined portion;
The cylindrical outer surface has a flat portion with a constant axial diameter. The flat portion has an arc-shaped first transfer groove that contacts the first row of rolling elements, and the second row of rolling elements. Is an inner ring that comes into contact with the flat part,
A retainer for holding a first row of rolling elements in contact with the first transfer groove;
A detachment preventing portion provided in the end portion direction of the second transfer groove and preventing the second row of rolling elements from detaching from the second transfer groove;
A bearing comprising: a plate which is provided at both ends of the outer ring and the inner ring and which forms a space for accommodating the first row of rolling elements and the second row of rolling elements together with the outer ring and the inner ring.

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