JPS6118255Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a linear motion bearing (a linear motion bearing) that is interposed between a moving body that performs linear motion along the axis and the shaft. A retainer, etc. that holds a large number of rolling elements arranged in a row in the outer cylinder of the bearing does not escape from the outer cylinder in the axial direction when the outer cylinder attached to the moving body moves linearly in the axial direction. In order to stop it,
This relates to a locking structure for a retaining ring for a linear motion bearing used between both axial ends of a retainer of the linear motion bearing and an outer cylinder, and the retaining ring prevents the outer cylinder from moving linearly. It can prevent foreign matter from entering the inside of the bearing from the shaft, it can be stably installed in the mounting circumferential grooves at both ends in the outer cylinder of the linear motion bearing, and the shaft hole into which the shaft is inserted has good dimensional stability. The object of the present invention is to provide a locking structure for a retaining ring for a linear motion bearing that is easy to manufacture and install.

Conventionally, a retainer is composed of an outer cylinder (also called a cylinder), a rolling element, a retainer, and a retaining ring for the retainer, and the rolling element is held within the retainer and the retainer is fitted into the outer cylinder. A known linear motion in which a device is fitted and locked at both ends into the outer cylinder via retaining rings, and can make infinite linear motion in the axial direction while rolling in contact with the shaft via the rolling elements. Bearing (also called ball bushing)
The retaining ring for securing the retainer etc. to the outer cylinder is the first one.
As shown in Figures and Figure 2, annular cylinders with a part of the circumference cut out in the radial direction are commonly used, but when the outer cylinder moves linearly on the shaft, it attaches to the shaft from the notch. This has the disadvantage that foreign matter such as dust can enter the bearing, and since it is simply fitted into the mounting groove provided at the end of the outer cylinder of the bearing, the voltage applied to the retaining ring is reduced when the outer cylinder moves linearly in the axial direction. It has the disadvantage that it is weak against the generated axial pressing force, is unstable in its attachment to the outer cylinder, and has the disadvantage that the diameter of the shaft hole of the retaining ring into which the shaft is inserted is not stable.

Therefore, conventionally, as shown in Fig. 3A and B,
A truncated conical part 3 is forcefully fitted into a mounting circumferential groove 2 formed in a tapered shape in the outer cylinder 1 using a jig 5,
A retaining ring 3' that is attached in an annular shape has been proposed, but this also has the disadvantage that the dimensional stability of the shaft hole 4 is poor, and the stability of the attached state is not necessarily sufficient.

The present invention provides a locking structure for a retaining ring for a linear motion bearing that can eliminate all of the drawbacks of conventional retaining rings and is easy to manufacture and install by having the configuration described in the claims of the utility model registration. That's what I got.

The configuration of the present invention will be explained in detail below based on the drawings.

In the embodiments shown in FIG. 4, FIG. 5, FIG. 6, and FIG. 21, the cylindrical portion 23 and the annular lip 24 are formed into a continuous pot shape.

As shown in FIGS. 6 and 7, the outer cylinder 10 has a second short circular hole 13 with a smaller diameter and shorter than the third circular hole 13 at the inner end of the short third circular hole 13 bored at both ends in the axial direction. A circular hole 12 is bored coaxially with the second circular hole 12.
A first circular hole 11 having a smaller diameter than the second circular hole 12 and into which the retainer is fitted is coaxially bored at the inner end of the outer cylinder 10, A mounting circumferential groove 1 having a larger diameter and shorter axial length than the third circular hole 13 is provided between the circular hole 13 and the second circular hole 12.
4 are coaxially formed, and the retaining ring 20 is
It is fitted into both ends of the outer cylinder 10.

The planar disk-shaped annular portion 21 forming the pot-shaped bottom of the retaining ring 20 is provided with a shaft hole 22 on the shaft center side into which the shaft is inserted after the bearing is mounted on the moving body. The portion 23 is continuously formed into a cylindrical shape by pressing or the like from the outer end of the annular portion 21 outward in the axial direction, and is formed to have an outer diameter that can be fitted into the second circular hole 12 of the outer cylinder. Said annular lip 24
is expanded radially outward from the outer tip of the cylindrical portion 23, has an outer diameter smaller than the third circular hole 13 which is larger in diameter than the second circular hole 12, and has a stopper. The outer circumferences of the annular portion 21, cylindrical portion 23, and annular lip 24 of the ring 20 are not provided with any irregularities.

The axial length of the cylindrical portion 23 and the annular lip 2
The combined length of 4 in the radial direction is the second
The length of the circular hole 12 in the axial direction and the length of the circumferential mounting groove 14 in the radial direction are approximately equal to each other.

As shown in FIG. 6, the retaining ring 20 having the above shape has the annular portion 21 in contact with the shoulder portion 33 formed between the first and second circular holes 11 and 12 of the outer cylinder 10, and With the inner cylindrical portion 23 fitted into the second circular hole 12 and the annular lip 24 present in the third circular hole 13, as shown in FIG. Pressed from the side in the axial direction,
Folded and expanded.

The jig 30 includes a holding portion 31 that fits into the cylindrical portion 23 of the retaining ring 20, and an annular lip 24.
The jig 30 has a bending part 32 which is bent and expanded by pressing the jig 30 from its outer end surface, and the working end part is formed in a convex shape, and as shown in FIG.
By pushing the annular lip 24 axially in the direction of the first circular hole 11 through the circular hole 13, the annular lip 24 is pushed radially outward at the bent portion 32, and the cylindrical portion 2
The outer end side and the annular lip 24 side portion from the intermediate portion of the annular lip 24 are bent and expanded radially outward, and the annular lip 24 is fitted into the mounting circumferential groove 14 from its tip end.

The end face of the pressing part 31 of the jig 30 is the annular part 21
At the final stage of the pressure mounting process, the
As shown in FIG. 7, the portion from the intermediate portion of the cylindrical portion 23 to the annular lip 24 is firmly bent and expanded outward in the radial direction perpendicular to the axis of the cylindrical portion 23, and a strong pressure is applied to the mounting circumferential groove 14. The retaining ring 20' in this attached state has the shoulder portion 33 between the first and second circular holes 11 and 12, the second circular hole 12, and the mounting circumferential groove 14. An annular part 21 and a half part 2 on the outer end side of the cylindrical part are located in the space spanning
3' and the bent and expanded flange 25 have a crank-shaped cross section and are caulked together.

As shown in FIG. 7, in the retaining ring 20' having the above-mentioned structure, the flange 25 is forcefully fitted into the mounting circumferential groove 14, and the shoulder portion 3 between the first and second circular holes 11 and 12
3, the second circular hole 12, and the mounting circumferential groove 14 are stored in an expanded form with a crank-shaped cross section, and the outer diameter surface of the expanded flange 25 and the mounting circumferential groove 14 Since it is not in contact with the groove bottom surface 34, it is stably and strongly attached, and prevents members such as a retainer (not shown) stored in the outer cylinder 10 from escaping in the axial direction. do.

Also, during the installation process of the retaining ring 20',
Since the outer diameter surface of the expanded flange 25 and the groove bottom surface 34 of the mounting circumferential groove 14 are not in contact with each other,
Since the diameter of the shaft hole 22 does not change at all, the shaft hole 2
2 can be formed to match the diameter of the shaft to be inserted, and the shaft and the shaft hole 22 can be formed with a suitable fit, so that the annular portion 21 has the role of a seal against the shaft. be able to.

Next, the embodiment shown in FIG.
The structure is different from that shown in FIG. 5, except that a seal 26 made of a resilient material is attached concentrically to the shaft hole 22 on the outer surface of the annular portion 21 of the retaining ring main body 20'' having the same shape as that shown in FIG. , the assembly method is the same as that shown in FIGS. 4 to 7 above.

The present invention has the structure and operation described in detail above, in which second and third circular holes having a larger diameter and shorter lengths are bored at both ends of the first circular hole in the center of the outer cylinder. 2,
The flange of the retaining ring is forcefully expanded and fitted into the mounting circumferential groove between the third circular hole, and the shoulder between the first and second circular holes of the outer cylinder and the second circular hole and the Since the annular part, half of the cylindrical part, and the flange are tightly housed in a crank-shaped cross section in the space leading to the mounting circumferential groove, the retaining ring can be attached to the outer cylinder extremely stably and strongly. This is effective in strongly preventing the cage, etc. housed inside the outer cylinder from escaping in the axial direction.

Furthermore, in the present invention, the diameter and shape of the retaining ring's shaft hole do not change at all before and after the retaining ring is assembled to the outer cylinder, so the shaft hole is pre-finished with high precision to ensure an appropriate fit. Since there are no gaps such as notches like in conventional retaining rings, when the shaft moves linearly,
This invention has the effect of preventing dirt, etc. from entering into the inside of the bearing.Furthermore, in this invention, the retaining ring before installation is formed into a roughly pan-shaped shape in which an annular part, a cylindrical part, and an annular lip are continuous, and the shape is relatively small. Because it is simple, it can be easily formed by drawing with a press of a metal plate, etc. When attaching the retaining ring to the outer cylinder, it can be bent and expanded radially outward when pressed with a jig. The annular lip is further expanded with a jig and securely fitted into the mounting groove, eliminating trouble during installation.Furthermore, it is easy to manufacture and install, as it is sufficient to press it with a jig. There are some very simple effects.

[Brief explanation of the drawing]

Figures 1 and 2 are front views of a conventional retaining ring with a notch, Figure 3 A is a longitudinal cross-sectional side view showing a conventional truncated conical retaining ring and how to attach it, and Figure 3 B is an installation. Fig. 4 is a front view of the present invention, Fig. 5 is a longitudinal side view of the invention, Fig. 6 is an explanatory diagram of how to install the device, Fig. 7 is a longitudinal side view of the device in its installed state, Fig. 8 FIG. 3 is a longitudinal sectional side view of another embodiment of the present invention. DESCRIPTION OF SYMBOLS 10... Outer cylinder, 11, 12, 13... First, second, and third circular holes formed in the outer cylinder, 14... Mounting circumferential groove, 20... Retaining ring in a state before installation, 21
...Annular part of retaining ring, 22...Coaxial hole, 23...
The same cylindrical part, 24...the same annular lip, 20'...the retaining ring in the installed state, 23'...half part of the cylindrical part,
25...flange formed by bending, 2
6... Seal, 33... Shoulder, 34... Groove bottom surface.

Claims (1)

[Scope of utility model registration request] It consists of an outer cylinder, a rolling element, a retainer, and a retaining ring for the retainer. In the linear motion bearing that is fitted and locked within the outer cylinder, and in which the shaft makes linear axial movement within the outer cylinder via the rolling elements, the outer cylinder includes:
A second circular hole smaller in diameter and shorter than the third circular hole is coaxially bored at the inner end of a short third circular hole bored at both ends in the axial direction. A first circular hole having a smaller diameter than the second circular hole and into which the retainer is fitted is coaxially bored at the end, and between the third circular hole and the second circular hole. A mounting circumferential groove having a larger diameter and shorter axial length than the third circular hole is formed coaxially with the retaining ring, and the retaining ring is pot-shaped;
The bottom surface of the cylindrical part is a planar disc-shaped annular part with a shaft hole formed in the axis center into which the shaft is inserted, and a flange is connected to the distal end of the cylindrical part on the outside in the radial direction. The retaining ring has an outer peripheral edge of the annular portion in contact with a shoulder between the first and second circular holes of the outer cylinder,
The cylindrical portion is fitted into the second circular hole, the flange is fitted into the circumferential mounting groove, and the outer edge of the flange is held at a position where it does not contact the bottom surface of the circumferential mounting groove. A locking structure for a retaining ring of a linear motion bearing, characterized by: