JP2563208Y2 - Cage with ball for linear bearing - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cage with a ball for a linear motion bearing, and more particularly to a small-diameter, rotatable cage with a ball for a linear motion bearing.

[0002]

2. Description of the Related Art A conventional small diameter ball bearing for a linear motion bearing has a cylindrical ring made of plastic or brass, and a large number of holes in the cylindrical ring project from the inner and outer peripheral surfaces of the cylindrical ring. Consists of a large number of balls held. When manufacturing this cage with a ball for a linear motion bearing, a large number of countersunk holes are drilled into the cylindrical ring from the outer periphery, and a number of countersunk holes are formed. The ball was rotatably held by crimping the peripheral edge of the countersunk hole opening on the outer peripheral surface of the cylindrical ring. However, since the cage is manufactured by caulking after being found by machining as described above, the resulting product has a drawback that the cost is increased.

On the other hand, a single-row ball cage used for a pivot type angular contact ball bearing is disclosed in Japanese Utility Model 3-24.
No. 891.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a ball bearing for a linear motion bearing which can be manufactured inexpensively and easily by using the known single row ball bearing. It is.

[0005]

In order to solve the above-mentioned problems, a single-row ball retainer is provided on an inner peripheral surface and an outer peripheral surface of a cylindrical ring in opposite directions at both axial end surfaces of the ring, respectively. It has a pair of U-shaped groove-shaped cuts that open, and the pair of U-shaped groove-shaped cuts are formed so as to be in contact with each other at a virtual cylindrical surface substantially intermediate between the inner peripheral surface and the outer peripheral surface. A plurality of this pair of grooved cuts are arranged in the circumferential direction, and the alternately opposed bottom portions of the outer and inner grooved cuts are formed on a ball support surface having a center at the axial center of the intermediate virtual cylindrical surface. Forming and straightening adjacent inner and outer channel-shaped notches into a common cylindrical surface portion extending in the axial direction near the center of the axial length of the retainer; Virtual circle of the retainer formed by a cylindrical surface portion connected to extend to The radial length from the surface to the inner peripheral surface and the outer peripheral surface is formed smaller than the radius of the ball, and at least the distance between the inner edge of the bottom portion of the inner grooved notch and the opposing inner edge of the straight portion is set to the ball. In a single row of cages with balls provided with ball pockets formed to be smaller than the diameter of the cage, according to the invention, furthermore the inner edge of the bottom part of the groove-shaped cutout on the outside of the cage and the opposite of the straight part are opposite. The distance between the inner edges is also formed so as to be smaller than the diameter of the ball, joints having structures complementary to each other are provided on both end faces in the axial direction of the retainer, and the entire retainer is formed of an elastomer material, thereby forming a single row. It is sufficient that a plurality of retainers can be connected in the axial direction.

[0006] The joints at both ends in the axial direction of the retainer are preferably composed of an annular projection and an annular concave portion which can be fitted to each other.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments shown in the drawings. The ball cage for a linear motion bearing according to the present invention is constructed using a single-row ball cage of a miniature pivot type angular contact ball bearing known from Japanese Utility Model Publication No. 3-24891.

This single row of ball-mounted cages 40 is shown in FIGS. A pair of U-shaped groove-shaped cuts 44 (FIG. 11) and 44 'opening upward and downward in opposite directions are formed on the inner peripheral surface and the outer peripheral surface of the cylindrical ring 42 having a rectangular cross section, respectively. A pair of groove-shaped cuts 44, 44 'are formed in the circumferential direction so as to be in contact with each other at a virtual cylindrical surface 46 substantially at the middle of the surfaces. An arcuate bottom portion 48, 48 'of adjacent inner and outer grooved cuts 44, 44', which are staggered up and down, has a ball bearing surface centered at the axial center on said intermediate virtual cylindrical surface 46. Is formed. This ball bearing surface forms part of a spherical surface having a diameter slightly larger than the diameter of the ball. Also, straight portions 50, 50 'of adjacent inner and outer channel cuts 44, 44'.
Have a common cylindrical surface portion A (see also FIG. 9) extending in the axial direction near the center of the axial length. This common cylindrical surface portion A ensures the strength of the grooved cuts 44, 44 '. Straight portions 50, 50 'of channel cuts 44, 44'
Respectively form part of the cylindrical surface BA, B'A extending in the axial direction with a radius slightly larger than the ball 14 centered in the axial center on the intermediate virtual cylindrical surface 46.
That is, alternate cylindrical surfaces B and B 'are formed vertically, and these upper and lower cylindrical surfaces B and B' are connected by a cylindrical surface A near the center in the axial direction. further,
The spacing 1 (FIG. 9) between the inner edge of the bottom portion 48 of the inner channel cut 44 and the opposite inner edge of the straight portion 50 is formed to be smaller than the diameter of the ball. In this way, a ball pocket is formed. The single-row retainer thus configured is molded by a mold using a moldable elastomer material. In the mold, the groove-shaped cut 44 opening upward can be formed by a cylindrical upper mold and the groove cut 44 'opening downward can be formed by a cylindrical lower mold, so that the mold can be simplified and disassembled. In this case, the upper mold and the lower mold can be easily disassembled simply by pulling them apart. Also,
When the ball 14 is incorporated into the retainer 40, the retainer made of elastomer is easily deformed, so that the ball 14 can be mounted simply by pushing the ball into the ball pocket.

In the single-row ball-mounted cage 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, and It is sufficient that the inner edge of the inner grooved cut is smaller than the diameter of the ball because the ball is always supported by the outer ring of the outer ring, but in the present invention, the inner edge of the bottom portion 148 'of the outer grooved cutout 144' and The spacing l '(FIG. 2) between the opposing inner edges of the straight section 150' must also be made smaller than the ball diameter. Further, according to the present invention, joints having structures complementary to each other are provided at both ends in the axial direction of the single-row cage with balls. That is, 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 obliquely at both axial ends of the retainer 40 so as to be suitable for the pivot type angular contact ball bearing. , 54 (FIG. 10) are formed. According to the present invention, as shown in FIGS. 1 and 2, the joint includes an annular projection 156 and an annular recess 157 formed on one axial end surface of the cage. And an annular projection 156 'and an annular recess 157' formed on the other end face. In the figure, the same parts as those of the well-known single-row cage are denoted by the same reference numerals with 100 added. The annular projection 156 'and annular recess 157' on the other end face have a shape that complements the annular projection 156 and annular recess 157 on one end face. Therefore, a plurality of cages 140 having the structure shown in FIGS.
Can be connected in the axial direction by fitting the joints at both ends in the axial direction to each other. The diameter dimensions of the projections and recesses are dimensioned so that they are pressed in by slightly pressing the cage in the axial direction.

FIG. 5 shows, as an example, a rotatable linear motion bearing having a ball bearing for linear motion bearing constituted by connecting four single-row ball cages of the present invention. 161 is the shaft inserted into the ball cage, 16
Reference numeral 2 denotes an outer cylinder fitted to the outer circumference of the cage with balls. This cage with a ball for a linear motion bearing can be assembled by connecting an appropriate number of single-row cages with a ball by joints at both ends thereof according to the length of the shaft of the linear motion bearing and the load capacity. . Fig. 6 shows a linear motion bearing in which a spacer 171 provided with a joint having the same shape as the joint of the cage at both ends is inserted between two single-row cages with balls according to the present invention and connected to the cage. 1 shows a rotatable linear motion bearing having a cage with ball for use. 172 is a shaft, 173 is an outer cylinder, 174 is a stop ring or O-ring. Since this example has a small number of balls, it is suitable for a linear motion bearing having a long shaft and capable of rotating for low friction and light load.

The shape of the joint at both ends of the retainer 140 is shown in FIG.
Not only the right-angled projections and recesses shown in FIG. 1, but also the projections 158, 158 'which are fitted to each other have tapered axial fitting surfaces as shown in FIG. It can be deformed and fitted so that it does not come off in the axial direction. Also, as shown in FIG.
Even if annular projections 159a, 159a 'having an arc-shaped cross section are provided at the distal end portions of the axial fitting surfaces of 159, 159', they can be elastically deformed and fitted when the retainers are interconnected. Similarly, it can be prevented from coming off in the axial direction.

[0012]

According to the present invention, a single-row cage with balls, which is formed of an elastomer, is provided with joints having complementary shapes at both axial ends of the cage. By simply pressing the shaft in the axial direction, 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, a cage with a ball for a linear motion bearing can be manufactured at a lower cost than conventional machining.

[Brief description of the drawings]

FIG. 1 is an enlarged longitudinal sectional view of a cage with a ball for a linear motion bearing according to the present invention.

FIG. 2 is a plan view of the cage with a ball for a linear motion bearing of FIG. 1;

FIG. 3 is a cross-sectional view showing a U-shaped groove cut including a partial cross-section taken along line III-III in FIG. 2;

FIG. 4 is a partial detailed view of a U-shaped groove cut as viewed from a direction of an arrow IV of FIG. 2;

FIG. 5 is a longitudinal sectional view of a rotatable linear motion bearing formed by connecting a plurality of single-row ball cages according to the present invention;

FIG. 6 is a longitudinal sectional view of a low-friction light-load rotatable linear motion bearing constructed by inserting and connecting spacers between single-row cages with balls according to the present invention;

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

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

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

FIG. 10 is a longitudinal sectional view taken along the line XX of FIG. 9;

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

[Explanation of symbols]

 114 Ball 140 Single-row ball retainer 142 Cylindrical ring 144, 144 'U-shaped grooved cut 146 Virtual cylindrical surface 150, 150' Linear portion of grooved cut A Common cylindrical surface portion B, B 'Cylindrical surface Part 156,156 'Annular projection of coupling 157,157' Annular recess of coupling

Claims (2)

(57) [Scope of request for utility model registration] 1. A single-row ball retainer has a pair of U-shaped grooves formed in the inner peripheral surface and the outer peripheral surface of a cylindrical ring, each opening in opposite directions at both axial end surfaces of the ring. And
The pair of U-shaped groove-shaped cuts are formed so as to be in contact with each other at a virtual cylindrical surface substantially intermediate between the inner peripheral surface and the outer peripheral surface,
A plurality of this pair of groove-shaped cuts are arranged in the circumferential direction, and a bottom portion of the outer and inner groove-shaped cuts that alternately faces each other is formed on a ball support surface having a center at the axial center of the intermediate virtual cylindrical surface. And the straight portions of the adjacent inner and outer channel cuts are staggered with a common axially extending cylindrical portion (A) near the center of the axial length of the retainer. A cylindrical surface portion (B, B ') connected so as to extend in the axial direction, and each radial length from the virtual cylindrical surface of the retainer to the inner peripheral surface and the outer peripheral surface is smaller than the radius of the ball. A single row of ball-shaped retainers formed with a ball pocket formed by forming the spacing between the inner edge of the bottom portion of the inner channel cut and the opposite inner edge of the straight portion less than the diameter of the ball In the vessel, A joint having a structure in which the distance between the inner edge of the bottom portion of the groove-shaped cutout on the outer side of the cage and the opposite inner edge of the straight portion is also formed to be smaller than the diameter of the ball, and is complementary to both axial end surfaces of the cage. And a cage with a ball for a linear motion bearing, wherein a plurality of single-row cages can be connected in the axial direction by molding the entire cage with an elastomer material. 2. The cage with a ball for a linear motion bearing according to claim 1, wherein the joints at both end faces in the axial direction of the cage are each formed of an annular projection and an annular recess having a structure capable of fitting with each other. .