JP2020063839A - Stop ring for direct-acting bearing and direct-acting bearing - Google Patents

Abstract

To provide a synthetic resinous stop ring installed to an annular groove of a direct-acting bearing including an outer cylinder equipped with the annular groove formed along a circumference on an inner peripheral side surface near end portions on both sides, a spherical holder, and a sphere group stored and held in the spherical holder, the stop ring facilitating installation to the annular groove and enabling the certain fixing of the spherical holder in the inside of the outer cylinder.SOLUTION: A synthetic resinous stop ring is formed in a stepped-shape in a radial direction from an annular outer peripheral side surface so as to include a large-diameter portion to be fitted in the inside of an annular groove formed along a circumference on an inner peripheral side surface near both end portions of the outer cylinder, and a small-diameter portion extending from the large-diameter portion in a thickness direction, and is preferably formed in an elliptical shape .SELECTED DRAWING: Figure 4

Description

  The present invention relates to a snap ring made of synthetic resin suitable for mounting on a linear motion bearing, and a linear motion bearing equipped with this snap ring.

  Patent Document 1 describes an example of a typical configuration of a linear motion bearing (also called a linear bearing) that has been conventionally used as a bearing for guiding relative reciprocating motion of a shaft in a linear direction. Configuration diagrams of the linear motion bearing described in Patent Document 1 in this specification are shown as FIGS. 1 to 3. FIG. 1 is a perspective view showing the appearance of a linear motion bearing, and FIG. 2 is a partial cross-sectional view showing a state in which a shaft body is inserted in the linear motion bearing. 3 is a cross-sectional view of the linear motion bearing of FIG. 1 viewed from the axial direction.

  The linear motion bearing 10 shown in FIGS. 1 to 3 includes an outer cylinder 11 having groove portions (concave grooves) 11a and 11b formed along the circumference on the inner peripheral surface near each of both ends; A cylindrical spherical retainer (also referred to as a retainer) that is mounted inside 11 and has elongated openings (slits) 12a and 12b extending in the length direction of the outer cylinder 11 formed on the outer peripheral surface and the inner peripheral surface, respectively. 12; and a sphere group (usually a plurality of steel balls) housed and held inside the sphere holder 12 so as to be movable under rotation while slightly protruding through the openings 12a and 12b. Group of 13).

  Retaining rings (also referred to as snap rings) 14a for preventing the spherical retainer 12 from falling out of the outer cylinder 11 are formed in the groove portions 11a and 11b formed on the inner peripheral surface near each of both ends of the outer cylinder 11. , 14b are mounted.

In the cross-sectional view shown in FIG. 3, irregularities are formed on the inner peripheral surface of the outer cylinder 11 along the circumferential direction, and the outer peripheral surface of the spherical retainer 12 corresponds to the inner peripheral surface of the outer cylinder 11. Although it is assumed to have irregularities along the shape, these shapes are shapes for preventing circumferential rotation of the spherical cage 12 inside the outer cylinder 11, and are essential for a linear motion bearing. Not a perfect shape.
In FIG. 2, a separator 15 is inserted to avoid direct contact between adjacent spheres in the sphere group housed in the sphere holder 12, but the separator 15 is also included. It is an arbitrary member.

  The shaft body 16 guided by the linear motion bearing 10 is inserted into the inner peripheral side of the spherical cage 12. The sphere group 13 housed in the sphere holder 12 is reciprocated relative to the lengthwise direction of the shaft body 16 to cause the sphere holder 13 to move inside the outer cylinder 11 under a pressure condition inside the sphere holder 12. While in contact with the peripheral surface, the ball moves circularly while rotating along the spherical circulation path 17.

  Patent Document 1 describes that the snap ring is a member formed of an elastic material such as a metal material or a resin material, and having a C-shaped shape with a part cut out in the circumferential direction. Then, in the assembly of the linear motion bearing, the retaining ring is inserted inside from the opening of the end portion of the outer cylinder in a state of being elastically deformed so as to reduce the outer diameter by applying a force to the outer peripheral edge portion. There is a description that when it reaches the inside of the annular groove of the outer cylinder, it returns to its original shape and is housed and arranged inside the annular groove.

JP, 2009-287645, A

  The C-shaped (C-shaped) retaining ring made of a metal material to be mounted on the linear motion bearing having the above-mentioned structure is effective as a means for preventing the spherical retainer from slipping out of the outer cylinder, and is still present. Commonly used. However, the C-shaped snap ring made of a metal material exhibits a strong resistance to the elastic deformation required for mounting in the outer cylinder, so that the mounting work is smoothly performed. Therefore, skilled skill is required, and it is not easy for even a skilled worker to perform the mounting work quickly (that is, within a short time). In particular, it is becoming more difficult to mount a retaining ring made of a fine metal material, which is necessary for producing a minute linear motion bearing, which has been in increasing demand in recent years, inside an outer cylinder.

  On the other hand, the C-shaped snap ring made of resin material, which is referred to in Patent Document 1, is relatively easy to mount in the outer cylinder, but is a discontinuous snap ring having a cut surface in the middle. However, after mounting, there is a problem that the spherical retainer lacks reliability and stability as a means for preventing the spherical retainer from coming off from the outer cylinder. Therefore, the C-shaped retaining ring made of a resin material as the retaining ring to be mounted on the linear motion bearing has not been widely used.

  The inventor of the present invention has studied the problems of the C-shaped snap ring made of a metal material that has been generally used in the past and the C-shaped snap ring made of a synthetic resin that has already been proposed. In place of these retaining rings for linear motion bearings, research was conducted for the purpose of developing retaining rings that could be easily mounted inside the outer cylinder and that could realize the function of preventing the spherical retainer from slipping out after mounting. . As a result of the research, a synthetic resin retaining ring having a novel structure described below is effective in solving the problem (that is, the problem) of the conventionally known retaining ring for a linear motion bearing. The inventors have found out that there is and have reached the present invention.

  The present invention relates to an outer cylinder having annular grooves formed along the circumference on the inner peripheral surface near each of both ends; the outer peripheral surface and the inner peripheral surface mounted inside the outer cylinder. A cylindrical sphere holder in which an elongated opening extending in the length direction (that is, the axial direction) of the outer cylinder is formed; and in the sphere holder, openings formed in the outer peripheral surface and the inner peripheral surface are formed. Via a synthetic resin stopper having an annular shape to be mounted in the annular groove of the outer cylinder of the linear motion bearing including the spherical group housed and held so as to be movable under rotation while slightly protruding A ring, wherein the retaining ring includes a large-diameter portion fitted into the annular groove of the outer cylinder and a small-diameter portion extending from the large-diameter portion in the thickness direction. A snap ring made of synthetic resin characterized by being formed in steps from the side surface in the radial direction. That.

The preferred embodiments of the synthetic resin retaining ring of the present invention are described below.
(1) The annular shape before being attached to the annular groove of the outer cylinder is an elliptical shape, and the outer diameter of the elliptical annular in the minor axis direction (outer diameter of the major diameter portion in the minor axis direction) is When set to 1, the outer diameter in the major axis direction (outer diameter in the major axis direction of the large diameter portion) is in the range of 1.02 to 1.20.
(2) The shape of the circular ring before being attached to the annular groove of the outer cylinder is elliptical, and the notches are provided at the symmetrical positions along the minor axis direction of the inner peripheral portion of the circular ring of the elliptical shape. Has been formed.
(3) The shape of the circular ring before it is attached to the annular groove of the outer cylinder is an elliptical shape, and the notches are provided at the symmetrical positions along the minor axis direction of the inner peripheral portion of the circular ring of the elliptical shape. It is formed and is bent with an imaginary line connecting the cutouts as a fold.
(4) An annular seal member obtained by molding a synthetic resin or rubber material that is softer than a synthetic resin retaining ring is mounted on the inner peripheral surface of the annular ring.
(5) It has a curved shape when there is no pressure load.
(6) The shape of the circular ring before being attached to the annular groove of the outer cylinder has an elliptical shape, and has a curved shape along the major axis direction of the elliptical shape.
(7) The annular ring has a discontinuous C-shaped shape cut in the radial direction, and both ends of the retaining ring along the cut portion can be overlapped with each other along the plane of the annular ring. Has a shape.

  The present invention also provides an outer cylinder having an annular groove formed along the circumference on the inner peripheral surface near each of both ends; each of the outer peripheral surface and the inner peripheral surface mounted inside the outer cylinder. A cylindrical sphere holder in which an elongated opening extending in the length direction (that is, the axial direction) of the outer cylinder is formed; and an opening formed in each of the outer peripheral surface and the inner peripheral surface in the sphere holder. A linear motion bearing including a group of spheres housed and held so as to be movable under rotation in a state of slightly projecting through the inner groove of the outer cylinder in the annular groove of the outer cylinder. Made of synthetic resin formed stepwise in the radial direction from the outer peripheral side surface of the annular ring so as to include a large-diameter portion to be fitted in and a small-diameter portion extending from the large-diameter portion in the thickness direction. There is also a linear bearing with a retaining ring.

  The retaining ring made of synthetic resin of the present invention has a large diameter portion fitted into an annular groove formed along the circumference on the inner peripheral side surface near both ends of the outer cylinder of the linear motion bearing, and a large diameter portion thereof. The small-diameter portion extending in the thickness direction from the diameter portion is formed in a stepwise manner along the radial direction from the outer peripheral side surface of the ring. Then, by reducing the thickness of the large diameter portion of the retaining ring, an annular groove formed along the circumference on the inner peripheral surface near the both ends of the outer cylinder of the normal linear motion bearing (usually, Since it is assumed that a retaining ring made of a metal material is attached, it can be easily attached to an annular groove having a narrow groove width. The existence of the small diameter portion extending from the large diameter portion in the thickness direction (the small diameter portion is not inserted into the annular groove) allows the entire retaining ring to have a sufficient thickness, so that the synthetic resin retaining ring It becomes possible to make up for the weakness, which is the weakness in the thickness direction. Therefore, it is installed inside the spherical cage of the linear motion bearing, and is prevented from falling out of the outer cylinder of the spherical cage in a state in which pressure for reciprocating movement is applied by contact with the shaft body that repeats reciprocating movement. It can be effectively prevented.

  Further, the synthetic resin retaining ring of the present invention is formed into an elliptical shape, and is inserted into the annular groove of the outer cylinder of the linear motion bearing in the direction along the major axis of the elliptical shape (longitudinal direction). It becomes easy to insert into. After being attached to the annular groove of the outer cylinder, the elliptical retaining ring made of synthetic resin is deformed along the shape of the annular groove having a perfect circle shape to become a substantially perfect circular shape.

  Further, the synthetic resin retaining ring of the present invention, the shape of the ring before being attached to the annular groove of the outer cylinder is elliptical, the symmetrical position along the minor axis direction of the elliptical ring. With the configuration in which the notch portion is formed in each inner peripheral portion, the insertion of the linear motion bearing into the annular groove of the outer cylinder is further facilitated.

  Alternatively, the retaining ring made of the synthetic resin of the present invention has an elliptical shape of the ring before being attached to the annular groove of the outer cylinder, and has a symmetrical position along the minor axis direction of the elliptical ring. It is easier to insert the linear bearing into the annular groove of the outer cylinder of the linear motion bearing by forming cutouts on each inner circumference and folding the cutouts along the imaginary line that connects the cutouts. Becomes

  Alternatively, by making the synthetic resin retaining ring of the present invention have a curved shape before being mounted in the annular groove of the outer cylinder, it becomes easy to insert the linear motion bearing into the annular groove of the outer cylinder. The curved synthetic resin retaining ring also has an elliptical shape (the shape of the ring before being mounted in the annular groove of the outer cylinder), so that the annular groove of the outer cylinder of the linear motion bearing can be formed. It becomes easier to insert into.

  Alternatively, the retaining ring made of the synthetic resin of the present invention has a discontinuous shape (C-shaped) in which a circular ring is cut in the radial direction, and both ends of the retaining ring along the cut portion are Also, the linear motion bearing can be easily inserted into the annular groove by adopting a shape that can be overlapped with each other along the plane. This C-shaped snap ring is also inserted into the annular groove of the outer cylinder of the linear motion bearing by making the shape (the shape of the circular ring before being mounted in the annular groove of the outer cylinder) elliptical. Will be even easier. .

It is a perspective view showing the appearance of a known linear motion bearing to which a retaining ring is mounted. FIG. 2 is a partial cross-sectional view showing a state in which a shaft body is inserted in the linear motion bearing shown in FIG. 1. It is sectional drawing seen from the axial direction of the linear motion bearing shown in FIG. FIG. 1 is a plan view (top view) (A), a front view (B), and a sectional view (C) of a synthetic resin retaining ring according to the present invention. It is explanatory drawing of the shape of the elliptical retaining ring which is a preferable example of the synthetic resin retaining ring of this invention. It is sectional drawing which shows the structure of the linear motion bearing with which the snap ring made from the synthetic resin of this invention was mounted. An example of a preferable shape of the synthetic resin retaining ring of the present invention and each component of the linear motion bearing including the retaining ring are shown. FIG. 8 is a top view of the retaining ring having the shape shown in FIG. 7, a cross-sectional view (A) taken along the line AA of this top view, and detailed views (B) and (C) showing the details of the partial structure. 7A and 7B are sectional views showing a mounting process (before fitting) of the retaining ring having the shape shown in FIGS. 7 and 8 to the outer cylinder end of the linear motion bearing, and a state after mounting (after fitting). It is sectional drawing (B). An example of another preferable shape (curved shape) of the synthetic resin retaining ring according to the present invention and each component of the linear motion bearing including the retaining ring will be shown. FIG. 11 is a view showing a particularly preferable curved shape of the curved retaining rings shown in FIG. 10. FIG. 12 is a sectional view (A) showing a process of mounting the curved retaining ring shown in FIGS. 10 and 11 on an outer cylinder end portion of a linear motion bearing, and a sectional view (B) showing a state after mounting. Example (A) of yet another preferable shape (C-shaped) of the snap ring made of the synthetic resin according to the present invention (before mounting on the end of the outer cylinder) and the ring groove of the end of the outer cylinder of this snap ring. The shape (B) after mounting is shown. Sectional view (A) showing another structural example (retaining ring composite body) of the retaining ring made of synthetic resin according to the present invention, and sectional view (B) showing the state after mounting the annular groove at the end of the outer cylinder. is there.

  Next, with reference to the attached drawings, a synthetic resin retaining ring (including a retaining ring composite) according to the present invention and a linear motion bearing mounted with the retaining ring will be described in detail.

  4A, 4B, and 4C are a plan view (top view), a front view, and a cross-sectional view, respectively, of a retaining ring that should be called a basic model of a synthetic resin retaining ring according to the present invention. . That is, the retaining ring 20 made of the synthetic resin of the present invention has a large diameter portion 21 fitted into the annular groove (11a, 11b in FIG. 2) of the outer cylinder of the linear motion bearing, and the large diameter portion 21 in the thickness direction. The small-diameter portion 22 that extends is formed in a step shape along the radial direction from the outer peripheral side surface of the ring. The thickness of the large diameter portion 21 is determined based on the groove width of the annular groove (11a, 11b in FIG. 2) of the outer cylinder. Therefore, the large-diameter portion 21 has a thickness slightly smaller than the groove width of the annular grooves 11a and 11b (width inside the groove). On the other hand, the thickness of the small diameter portion 22 is not particularly limited, but considering the strength of the retaining ring made of synthetic resin and the ease of accommodation in the outer cylinder, the thickness of the large diameter portion 21 is set to 1 to 1 to It is preferably in the range of 3.

The shape of an elliptical retaining ring which is a preferred example of the synthetic resin retaining ring of the present invention will be described with reference to FIG. The elliptical shape in the elliptical retaining ring which is a preferred example of the synthetic resin retaining ring of the present invention does not need to be a strict elliptical shape in the meaning defined geometrically, and may be an egg shape or athletics. Like a truck in the field, it may be a circular shape whose major axis is larger than its minor axis or a modified type of the circular shape.
However, in the elliptical retaining ring 20 which is a preferred example of the retaining ring of the present invention, the ratio (x / y) of the large diameter portion 21 shown in FIG. 5 to the major diameter (x) and the minor diameter (y) is 1. It is preferably in the range of 02 to 1.20.

  FIG. 6 shows a cross-sectional view of the structure of the linear motion bearing to which the retaining ring made of the synthetic resin of the present invention is attached, taken along the major axis direction. The linear motion bearing 23 shown in FIG. 6 is similar to that shown in FIGS. 1 to 3 except that the retaining rings mounted in the annular grooves 24a and 24b are the retaining rings 20a and 20b made of the synthetic resin of the present invention. It is not substantially different from the linear motion bearing 10 shown.

FIG. 7 shows an example of the preferable shape of the synthetic resin retaining ring of the present invention and each component of the linear motion bearing including the retaining ring.
In FIG. 7, the linear motion bearing of the present invention is provided with an outer cylinder 25 having an annular groove 24 formed along the circumference on the inner peripheral surface near each of both ends; the outer cylinder 25 is mounted inside the outer cylinder. A cylindrical sphere retainer 26 having elongated openings extending in the lengthwise direction of the outer cylinder formed on the outer peripheral surface and the inner peripheral surface, respectively. It includes a group of spheres 27 housed and held so as to be movable under rotation in a state of slightly projecting through an opening 26a formed in the outer cylinder 26, and is further fitted into the annular groove 24 of the outer cylinder 25. The retaining ring 20 made of synthetic resin is formed stepwise in the radial direction from the outer peripheral side surface of the annular ring so as to include the diameter portion and the small diameter portion extending from the large diameter portion in the thickness direction. It

  The synthetic resin retaining ring 20 shown in FIG. 7 has notches formed in the respective inner peripheral portions at symmetrical positions along the minor axis direction of the ring of the retaining ring. It has a shape that is bent with a virtual line connecting the lines.

  The detailed structure of the synthetic resin retaining ring 20 shown in FIG. 7 will be described with reference to FIG. It is preferable that the synthetic resin retaining ring 20 also has an elliptical shape. In FIG. 8, the retaining ring 20 made of synthetic resin shown in a plan view (a state before being mounted in the annular groove of the outer cylinder, that is, a top view of the retaining ring in a bent state) is a ring of the retaining ring ( Notches 20a and 20b are formed in the respective inner peripheral portions at symmetrical positions along the minor axis direction of the (oval). Then, as shown in the cross-sectional view (A) taken along the line AA of the plan view, it is bent at a straight line (virtual line) connecting the cutout portions.

  8B is an enlarged view (detailed view) of a portion (cutout portion) indicated by B in the plan view, and FIG. 8C is an enlarged view of a portion indicated by C in the sectional view (A). (Detailed drawing) The retaining ring is continuous on the back surface (lower surface) on the outer peripheral side.

  FIG. 9 is a cross-sectional view showing a mounting process (before fitting) of the retaining ring 20 having the shape (folded shape) shown in FIGS. 7 and 8 into the annular groove of the inner peripheral portion of the outer cylinder end of the linear motion bearing. FIG. 3A is a sectional view showing a state after mounting (after fitting).

  The retaining ring made of synthetic resin of the present invention is manufactured by molding synthetic resin. The synthetic resin is not particularly limited, but when a pressure is applied, the bent state is transformed into a flat plane state, and when the pressure load disappears, it is bent into an original shape. It is preferable to use a synthetic resin that exhibits elasticity to such an extent that it can be deformed into a state. For example, a polyacetal resin, a polyphenylene sulfide (PPS) resin, or a polyether ether ketone (PEEK) resin can be used.

  The outer cylinder of the linear motion bearing is generally manufactured by casting a metal material, but it may be manufactured by molding a hard synthetic resin. Further, the spherical cage is usually manufactured by molding a resin material, but it may be manufactured from a metal material. And, as described above, in the spherical cage, when the shaft body is inserted into the linear motion bearing and the shaft body makes repeated relative reciprocating motion in the axial direction with respect to the linear motion bearing, It is possible to realize a smooth relative movement of the shaft body in the linear motion bearing by rotating the inner sphere group under pressure while circulating along the outer peripheral surface of the shaft body and the inner peripheral surface of the outer cylinder. The shaft supporting sphere rotating circuit and the ball returning path connecting both ends of the shaft supporting sphere rotating circuit.

  It should be noted that the structure of the linear motion bearing as described above is already known, and the linear motion bearing of such a structure is disclosed in various documents disclosing the linear motion bearing, and actually used in many configurations. Therefore, detailed description of the linear motion bearing having such a configuration is not required.

  As is clear from the above description, the synthetic resin retaining ring of the present invention is a retaining ring having an annular shape with a step formed on the outer peripheral side peripheral edge portion obtained by molding the synthetic resin. be able to.

  FIG. 10 shows an example of another preferable shape (curved shape) of the synthetic resin retaining ring according to the present invention, and each component of the linear motion bearing including the retaining ring. FIG. 10 is the same as FIG. 7 except that the shape of the snap ring 20 made of synthetic resin is changed. Further, FIG. 11 is also the same as FIG. 9 except that the shape of the synthetic resin retaining ring shown in FIG. 10 is changed.

  As shown in FIG. 11, the curved synthetic resin snap ring 20 is curved along the major axis direction. In the curved state, the distance between the two ends of the snap ring 20 in the major axis direction is large. Is preferably equal to or shorter than the length of the snap ring 20 in the minor axis direction. Since the length of the snap ring 20 in the minor axis direction is substantially equal to the diameter of the annular groove (the diameter of the bottom of the annular groove) of the outer cylinder, the length of both ends of the curved snap ring 20 in the major axis direction is large. The distance is substantially equal to the diameter of the annular groove of the outer cylinder, and in this case, when the retaining ring 20 made of synthetic resin is mounted in the annular groove of the outer cylinder, it is easy to engage the inside of the annular groove.

  FIG. 12 is a sectional view (A) showing a mounting process of the annular groove at the outer cylinder end of the linear motion bearing 10 of the curved snap ring shown in FIGS. 10 and 11, and a sectional view showing a state after mounting. (B).

  The curved retaining ring shown in FIGS. 10 and 11 is also preferably elliptical, and the elliptical retaining ring is inserted in the annular groove of the outer cylinder of the linear motion bearing in the direction along the major axis. By mounting it, it can be easily inserted into the annular groove, and after the insertion, it is deformed along the shape of the annular groove of the outer cylinder and becomes a substantially perfect circle.

FIG. 13 shows an example (A) of yet another preferable shape (C-shaped) of the synthetic resin retaining ring according to the present invention (before being attached to the outer cylinder end portion) and the outer cylinder end portion of this retaining ring. The shape (B) after mounting in the annular groove is shown. As shown in FIGS. 12A and 12B, the synthetic resin C-shaped snap ring of the present invention has a discontinuous shape in which the ring of the snap ring is cut in the radial direction. Yes, both ends of the retaining ring along the cut portion have a shape that can be overlapped with each other along the plane of the ring. In the C-shaped synthetic resin retaining ring shown in FIG. 13, both ends of the retaining ring along the cut portion are overlapped with each other and engage with each other. However, instead of such a complicated engagement shape, for example, one end is cut along the side surface of the retaining ring in a wedge shape and is attached to the annular groove of the outer cylinder, and the other end is first. It can also be shaped so that it can overlap the rusty edges.
Further, it is not always necessary to cut the synthetic resin snap ring in the radial direction, and the snap ring surface can be cut obliquely with respect to the radial direction.

  14 (A) and 14 (B) are partial cross-sectional views (A) showing another structural example (retaining ring composite body) of the synthetic resin retaining ring according to the present invention, and to the annular groove at the end of the outer cylinder. FIG. 7B is a sectional view showing a state after the mounting of FIG.

  In FIG. 14, an annular seal member 28, which is a similar annular member, is attached to the inside of the inner peripheral edge of the retaining ring 20 to form a retaining ring composite as a whole. In the retaining ring composite, a convex portion and / or a concave portion is formed on the inner peripheral surface of the retaining ring 20, and a concave portion and / or a concave portion bonded to each of the convex portion and / or the concave portion on the inner peripheral surface of the retaining ring. The convex portion is formed on the annular seal member 28. It should be noted that the annular seal member 28 may be provided with a notch so that its shape can be easily followed regardless of whether the retaining ring 20 is in the curved state or the horizontal state.

  The annular seal member 28 mounted on the synthetic resin retaining ring 20 shown in FIG. 14 is included in the linear motion bearing to prevent dust and dirt from entering the linear motion bearing from the outside environment. It shows the function of preventing oily substances such as lubricating oil from leaking to the outside. Therefore, in consideration of the use environment of the linear motion bearing of the present invention, a snap ring to which an annular seal member is not attached or a snap ring composite in which a snap ring and an annular seal member are combined is used. The annular seal member is usually made of a rubber material exhibiting elasticity, but can be manufactured by forming a synthetic resin as long as it exhibits elasticity.

  In addition, the retaining ring composite may be manufactured as an integral body from different kinds of synthetic resins by so-called “two-color molding”. In the retaining ring composite of this integrally molded product, the joint surface between the retaining ring and the annular seal member may be a simple smooth surface.

10 Linear Motion Bearings 11 Outer Cylinders 11a, 11b Annular Grooves 12 Sphere Holders 13 Spheres 14a, 11b Retaining Rings (Metal Material)
15 Shaft 20 Synthetic resin retaining ring of the present invention 21 Large diameter part 22 Small diameter part

Claims (9)

  An outer cylinder provided with an annular groove formed along the circumference on the inner peripheral surface near each of both ends; the length of the outer cylinder mounted inside the outer cylinder on each of the outer peripheral surface and the inner peripheral surface. A cylindrical sphere holder having elongated openings extending in the vertical direction; and a state in which the sphere holder slightly protrudes through the openings formed on the outer peripheral surface and the inner peripheral surface, respectively. A synthetic resin retaining ring having an annular shape that is mounted in the annular groove of an outer cylinder of a linear motion bearing that includes a group of spheres that are housed and held so that it can move while rotating. The resin retaining ring includes a large-diameter portion fitted in the annular groove of the outer cylinder and a small-diameter portion extending in the thickness direction from the large-diameter portion so as to extend radially from the outer peripheral side surface of the annular ring. Retaining ring made of synthetic resin, characterized in that it is formed in a staircase shape.   The shape of the circular ring before being attached to the annular groove of the outer cylinder is an ellipse, and when the outer diameter of the elliptical circular ring in the minor axis direction is 1, the outer diameter in the major axis direction is 1.02. The synthetic resin retaining ring according to claim 1, which is in a range of 1.20.   The shape of the ring before being attached to the annular groove of the outer cylinder is an ellipse, and notches are formed at symmetrical positions along the minor axis direction of the inner peripheral portion of the elliptical ring. The snap ring made of synthetic resin according to Item 1.   The shape of the annulus before being attached to the annular groove of the outer cylinder is an ellipse, and notches are formed at symmetrical positions along the minor axis direction of the inner peripheral part of the elliptical annulus, and they are The snap ring made of synthetic resin according to claim 1, wherein the snap ring is bent with an imaginary line connecting the cutout portions as a fold line.   The synthetic resin stopper according to claim 1, wherein an annular seal member obtained by molding a synthetic resin material or a rubber material, which is softer than a synthetic resin retaining ring, is attached to the inner peripheral surface of the annular ring. ring.   The synthetic resin retaining ring according to claim 1, which has a curved shape when no pressure is applied.   The synthetic resin retaining ring according to claim 1, wherein the shape of the circular ring before being mounted in the annular groove of the outer cylinder has an elliptical shape, and is curved in the major axis direction of the elliptical shape.   The ring has a discontinuous C-shaped shape that is cut in the radial direction, and both ends of the retaining ring along the cut portion can overlap each other along the plane of the ring. The synthetic resin retaining ring according to claim 1, which has.   An outer cylinder having an annular groove formed along the circumference on the inner peripheral surface near each of both ends; the length of the outer cylinder mounted on the inner surface of the outer cylinder and the outer cylinder. Cylindrical sphere holder having elongated openings extending in the depth direction; and rotation in the sphere holder slightly protruding through the openings formed in the outer peripheral surface and the inner peripheral surface, respectively. A linear motion bearing including a group of spheres housed and held so as to be movable downward, a large-diameter portion that is fitted into the annular groove of the outer cylinder, and a large-diameter portion that fits inside the annular groove of the outer cylinder. A linear motion bearing mounted with a snap ring made of synthetic resin, which is formed stepwise in the radial direction from the outer peripheral side surface of the annular ring so as to include a small diameter portion extending from the portion in the thickness direction.

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