JPH0622618U - Cage with ball for linear bearing - Google Patents

Abstract

(57) [Summary] [Objective] To provide a cage with balls for a linear motion bearing that can be manufactured at low cost. [Constitution] The single row ball cage (140) is a cylindrical ring.
A pair of U-shaped groove-shaped notches (14) that open in opposite directions at both axial end faces of the ring are formed on the inner and outer peripheral faces of (142).
4,144 '), and a plurality of these cuts are arranged in the circumferential direction, and the bottom portions (148,148') of the outer and inner groove-shaped cuts which are alternately opposed to each other are formed in the middle between the inner peripheral surface and the outer peripheral surface. Joints (156, 157 and 156 ′ and 157 ′), which are formed on the ball support surface centered in the axial center of the virtual cylindrical surface (146) and which complement each other on both axial end surfaces of the cage, are provided and held. The entire vessel is molded of elastomeric material. A plurality of single-row cages having the above structure can be connected in the axial direction by their joints to form a ball bearing cage for a linear motion bearing according to the shaft length and load.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a ball bearing retainer for linear motion bearings, and more particularly to a ball bearing retainer for linear motion bearings that has a small diameter and is also rotatable.

[0002]

[Prior art]

 The conventional cage with ball bearings for small diameter linear motion bearings has a cylindrical ring made of plastic or brass and a large number of holes in this cylindrical ring that protrude from the inner and outer peripheral surfaces of the cylindrical ring. It consists of a number of retained balls. When manufacturing this cage with balls for linear motion bearings, a large number of countersinks are drilled from the outer circumference into the cylindrical ring to open a large number of countersinks, and the balls are inserted from the outside into the countersink openings on the peripheral surface of the cylindrical ring. The ball was held rotatably by inserting and caulking the peripheral edge of the countersunk hole on the outer peripheral surface of the cylindrical ring. However, since the retainer is manufactured by caulking after it has been found by machining as described above, the finished product has a drawback of high cost.

On the other hand, a single-row cage with balls used for a pivot type angular contact ball bearing is known from Japanese Utility Model Publication No. 3-24891.

[0004]

[Problems to be solved by the device]

 An object of the present invention is to provide a ball bearing cage for a linear motion bearing which can be manufactured inexpensively and easily by using the above-mentioned known single row cage with balls.

[0005]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, a single-row ball retainer is provided with a pair of U-shaped groove-shaped grooves that open in opposite directions on both inner and outer peripheral surfaces of a cylindrical ring in the axial direction of the ring. And a pair of U-shaped groove-shaped notches are formed so as to be in contact with each other at a virtual cylindrical surface approximately in the middle between the inner peripheral surface and the outer peripheral surface. A plurality of circumferentially arranged bottom portions are formed on the ball support surface centered at the axial center of the intermediate imaginary cylindrical surface, and the bottom portions of the outer and inner groove-shaped cuts that are alternately opposed to each other are formed on the adjacent inner surfaces. A cylindrical portion that connects the straight portion of the outer groove cut with a common cylindrical surface portion that extends in the axial direction near the center of the axial length of the cage, and that extends in an axial direction that alternates with this cylindrical surface portion. It is formed by the surface part and from the virtual cylindrical surface of the cage to the inner peripheral surface and the outer peripheral surface. At the inner radius of the ball and at least the distance between the inner edges of the bottom and inner facing edges of the straight groove is less than the diameter of the ball. In a single-row cage with balls formed by forming a ball pocket in the same way, according to the invention, further between the inner edge of the bottom part of the groove notch and the opposite inner edge of the straight part of the cage, The spacing is also made smaller than the diameter of the balls, each of the cage's axial end faces is provided with a complementary joint structure, and the entire cage is made of an elastomeric material, so that a single row of retention is achieved. It suffices if a plurality of containers can be connected in the axial direction.

Conveniently, the joints on both axial end surfaces of the retainer are composed of an annular protrusion and an annular recess that are mutually engageable.

[0007]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. The ball cage for linear motion bearings according to the present invention is constructed by using the single row ball cage of the miniature pivot type angular contact ball bearing disclosed in Japanese Utility Model Publication No. 3-24891.

This single row ball cage 40 is shown in FIGS. 9 and 10. A pair of U-shaped groove-shaped notches 44 (Fig. 11) and 44 ', which open in the opposite direction upward and downward respectively, are formed on the inner peripheral surface and the outer peripheral surface of the cylindrical ring 42 having a rectangular cross section. A plurality of groove-shaped notches 44, 44 'are formed so as to be in contact with each other at a virtual cylindrical surface 46 substantially in the middle of the outer peripheral surface, and a plurality of groove-shaped notches 44, 44' are arranged in the circumferential direction. Ball bearing surfaces centered axially on the intermediate virtual cylindrical surface 46 with arcuate bottom portions 48, 48 'of adjacent inner and outer grooved notches 44, 44' which are vertically offset. Is formed in. This ball bearing surface forms part of a spherical surface with a diameter slightly larger than the diameter of the ball. Also, the straight portions 50, 50 'of the adjacent inner and outer grooved cuts 44, 44' have an axially extending common cylindrical surface portion A (see also FIG. 9) near the center of the axial length. To have. This common cylindrical surface portion A ensures the strength of the grooved cuts 44, 44 '. The straight portions 50, 50 'of the grooved notches 44, 44' respectively represent a portion of the axially extending cylindrical surface of slightly larger radius than the ball 14 centered axially on the intermediate virtual cylindrical surface 46. BA and B'A are formed. That is, upper and lower portions of the cylindrical surface B and B'which are staggered from each other are formed, and these upper and lower cylindrical surface portions B and B'are connected by the cylindrical surface portion A near the center in the axial direction. Further, the spacing l (FIG. 9) between the inner edge of the bottom portion 48 and the opposite inner edge of the straight portion 50 of the inner groove notch 44 is formed to be smaller than the diameter of the ball. In this way, the ball pocket is formed. The single-row cage thus configured is molded by a mold using a moldable elastomer material. The mold can be formed by the cylindrical upper mold for the grooved cut 44 opening upward and the cylindrical lower mold for the grooved cut 44 ′ opening downward, which simplifies the mold and facilitates disassembly. In that case, it can be easily disassembled simply by pulling the upper and lower molds apart. Further, when the balls 14 are incorporated in the cage 40, the cage made of elastomer is easily deformed, so that the ball 14 can be mounted simply by pushing it into the ball pocket.

[0009] In the cage with a single row of balls used for the pivot type angular contact ball bearing known from Japanese Utility Model Publication No. 3-24891 constructed as described above, the cage is mounted on the ball bearing. Since the ball is always supported by the outer ring of the ball bearing, it is sufficient if the inner edge of the inner groove cut is smaller than the diameter of the ball, but in the present invention, the bottom portion 148 of the further outer groove cut 144 'is sufficient. It is also necessary that the spacing l '(FIG. 2) between the inner edge of the'and the opposite inner edge of the straight portion 150' be smaller than the diameter of the ball. Further, according to the present invention, joints having complementary structures are provided at both axial ends of the single-row cage with balls. In other words, in the well-known single-row cage with balls, the upper edge of the inner peripheral surface and the lower edge of the outer peripheral surface are chamfered diagonally at both axial ends of the cage 40 so as to be suitable for the pivot type angular contact ball bearing. 52 and 54 (FIG. 10) are formed, according to the present invention, as shown in FIGS. 1 and 2, the joint has an annular projection 156 and an annular recess formed on one axial end face of the cage. 157 and an annular projection 156 'and an annular recess 157' formed on the other end surface. In the figure, parts similar to those of the known single-row cage are given similar reference numerals plus 100. The annular projection 156 'and the annular recess 157' on the other end surface have a shape that complements the annular projection 156 and the annular recess 157 on the other end surface. Therefore, the plurality of cages 140 having the structure shown in FIGS. 1 and 2 can be connected in the axial direction by fitting the joints at both ends in the axial direction to each other. The diametrical dimensions of the protrusions and recesses are sized to be press-fit by gently pressing the retainer axially.

FIG. 5 shows, as an example thereof, a linear motion bearing which is rotatable and has a ball bearing for linear motion bearing constituted by connecting four single-row ball cages of the present invention. Reference numeral 161 indicates a shaft inserted in the cage with balls, and 162 indicates an outer cylinder fitted around the outer circumference of the cage with balls. This ball cage for linear motion bearings can be assembled by connecting a suitable number of single-row ball cages with joints at both ends depending on the shaft length and load capacity of the linear motion bearing. it can. FIG. 6 shows a linear motion bearing in which a spacer 171 having a joint having the same shape as the joint of the retainer is inserted between two single-row retainers with balls according to the present invention and the spacer is connected to the retainer. Fig. 3 shows a linear motion bearing that has a cage with a ball for use and can also rotate. 172 is a shaft, 173 is an outer cylinder, and 174 is a stop ring or O-ring. Since this example has a small number of balls, it is suitable for a linear bearing that has a long shaft and can rotate for low friction and light loads.

Further, the shape of the joints at both ends of the cage 140 is not limited to the right-angled projections and recesses shown in FIG. 1, but the axial fitting surfaces of the projections 158, 158 ′ that fit with each other as shown in FIG. The taper can be tapered to elastically deform and fit when the cages are interconnected, thereby preventing axial dislodgement. Further, as shown in FIG. 8, annular protrusions 159a and 159a ′ having an arcuate cross section are provided at the tip end portions of the axial fitting surfaces of the protrusions 159 and 159 ′ so as to elastically connect the retainers to each other. Even if it is deformed and fitted, it can be prevented from coming off in the axial direction in the same manner.

[0012]

[Effect of device]

 According to the present invention, since the single row retainer made of elastomer, which is known per se, is provided with the joints having the shapes complementary to each other at both axial ends, the single row retainer with the ball is pressed in the axial direction. By simply doing so, the joint can be elastically deformed and connected easily, and the number of single-row cages can be freely adjusted according to the shaft length and load capacity of the linear motion bearing. Since the elastomer cage can be molded by a mold, the cage with balls for linear motion bearings can be manufactured at a lower cost than conventional machining.

[Brief description of drawings]

FIG. 1 is an enlarged vertical sectional view of a cage with balls for linear motion bearings according to the present invention.

FIG. 2 is a plan view of the cage with balls for linear motion bearing of FIG.

3 is a cross-sectional view showing a U-shaped groove cut, including a partial cross-section taken along line III-III of FIG.

FIG. 4 is a partial detailed view of the U-shaped groove cut as seen from the direction of the arrow of line IV in FIG.

FIG. 5 is a longitudinal sectional view of a linear motion bearing capable of rotation, which is formed by connecting a plurality of single-row cages with balls according to the present invention.

FIG. 6 is a vertical cross-sectional view of a linear motion bearing capable of rotating with low friction and light load, which is constructed by inserting and connecting spacers between the single-row cages with balls according to the present invention.

FIG. 7 is an enlarged partial cross-sectional view of an embodiment of a joint structure formed on both end surfaces of the single-row cage with balls according to the present invention.

FIG. 8 is an enlarged partial sectional view of another embodiment of the joint structure formed on both end surfaces of the single-row cage with balls according to the present invention.

FIG. 9 is a plan view of a known single-row cage with a ball used in the present invention.

10 is a vertical cross-sectional view taken along the line XX of FIG.

11 is a partial cross-sectional view of a U-shaped groove cut taken along line XI-XI of FIG. 10.

[Explanation of symbols]

 114 ball 140 single row ball retainer 142 cylindrical ring 144, 144 'U-shaped groove cut 146 virtual cylindrical surface 150, 150' linear portion of groove cut A common cylindrical surface part B, B'cylindrical surface Part 156, 156 'Joint annular projection 157, 157' Joint annular recess

Claims (2)

[Scope of utility model registration request] 1. A single-row ball retainer has a pair of U-shaped groove-shaped notches formed on the inner peripheral surface and the outer peripheral surface of a cylindrical ring, which are open at opposite axial end surfaces of the ring in opposite directions. Then
The pair of U-shaped groove-shaped notches are formed so as to be in contact with each other at a virtual cylindrical surface in the middle between the inner peripheral surface and the outer peripheral surface,
A plurality of pairs of groove-shaped cuts are arranged in the circumferential direction, and the bottom portions of the outer and inner groove-shaped cuts that are alternately opposed to each other are formed on the ball support surface having the center at the axial center of the intermediate virtual cylindrical surface. In addition, the linear portions of the adjacent inner and outer groove-shaped cuts are alternately formed with a common cylindrical surface portion (A) extending in the axial direction near the center of the axial length of the cage (A). And a cylindrical surface portion (B, B ') connected so as to extend in the axial direction, and the radial lengths from the virtual cylindrical surface of the cage to the inner peripheral surface and the outer peripheral surface are smaller than the radius of the ball. Retaining a single row of balls with ball pockets formed by forming the spacing between the inner edge of the bottom portion of the inner groove cut and the opposing inner edge of the straight portion to be less than the diameter of the ball In the bowl A joint having a structure in which the distance between the inner edge of the bottom portion of the grooved notch on the outside of the retainer and the opposing inner edges of the straight portions is also smaller than the diameter of the ball, and complements each other on both axial end faces of the retainer. And a retainer with a ball for a linear motion bearing, wherein the retainer is molded entirely of an elastomer material so that a plurality of single-row retainers can be connected in the axial direction. 2. The retainer with balls for linear motion bearings according to claim 1, wherein the joints on both axial end faces of the retainer are formed of an annular protrusion and an annular recess that are mutually engageable. .