JPS60184713A - Elastic spacer for roller bearing for endless rectilinear movement - Google Patents

Abstract

PURPOSE:To reduce stick slip by inserting a plurality of elastic spacers in equal intervals between the rolling bodies in an endless circulation path and absorbing the gap between the rolling bodies. CONSTITUTION:The inner cylindrical rollers 1 having the length nearly equal to the diameter are arranged on an endless circulation path alternately in directly contiguously, shifting the centers of the rotary shafts by 90 deg., and each A type elastic spacer is inserted in substitution for the cylindrical roller 1 at the position divided into three parts in a nearly equal pitch to the length L of the trajectory passage, in other words, one spacer is set into the load range 3, and two spacers are set into the load ranges 4 and 5, and thus absorption amount can be stabilized. In this case, a C-type spacer is inserted into a circumferential gap, and stick slip is generated artificially. Therefore, the intermittent sharp increase and reduction of the sliding resistance of the stick pipe is softened, and the large stick slip during the transfer from the upper to the lower can be avoided, and the sufficient effect can be developed even in use of a longitudinal type.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an elastic spacer for a rolling bearing for infinite linear motion.

Conventional spacers for rolling bearings are inserted between rolling elements such as rollers to prevent them from coming into direct contact with each other and to maintain a constant distance between them. Since the number of rolling elements is reduced, the load capacity is reduced, and the presence of spacers makes it impossible to downsize.

In order to eliminate this drawback, for example, as shown in Figure 1.2,
Linear motion with a so-called general cross-roller type, in which a large number of cylindrical rollers, each having their rotation axes 90" apart and directly adjacent to each other, circulate endlessly on an endless circulation path without a spacer that engages between the rollers. When roller bearings were developed, they focused on the fact that stick-slip occurs in bearings because the amount of rolling elements coming out and coming in at both ends of the raceway surface is not constant, that is, there is a change in the amount of coming and going. An infinite linear motion roller bearing that reduces the stick-slip by making the length of the load track and return path and the length of the direction change path connecting both ends of the direction straight path a predetermined multiple of the roller shaft diameter. Circulation route (Japanese Patent Application No. 1983-101467, Patent Application No. 59-48
No. 75) was proposed. In the figure, 1 is a roller, 2 is an endless circulation path, 3 is a linear load path, 4 is a linear return path, 5
is a semicircular turning path, 6 is a track rail, and 7 is a casing.

However, as a practical matter, the structure of the endless circulation path after assembly is difficult to control due to machining errors in the parts that make up the endless circulation path and play between the endless circulation path and the rolling elements. It is not always the minimum condition, and even under the minimum condition, small stick-slips occur and are not zero.

Therefore, even in a bearing with an endless circulation path structure under conditions other than ideal conditions, where the amount of change in inflow and outflow is large, if you take some measures to reduce the amount of change in inflow and outflow, stick-slip will be reduced, and even under ideal conditions. You can get close to things.

In view of this point, the present invention uses an elastic spacer to allow a large number of rolling elements to circulate in an endless circulation path, thereby reducing the circumferential clearance, which is a behavior characteristic of the rolling elements of a linear motion rolling bearing. The primary purpose is to absorb changes in increase and decrease.

The elastic spacer of the present invention also exhibits its effects in a rolling bearing for infinite linear motion shown in FIG. In the figure,
11 is a track base, 12 is a guide plate attached to both sides of the track base, and 13 is a stepped roller that endlessly circulates around the track base while being guided by the guide plate. This rolling bearing is shown in Figure 3 (B
) When using the state shown in ) rotated 180 degrees up and down, there is no gap between the rollers in the lower load area of the endless circulation path, and the gap is always on the side where the rollers enter the load area. Since it occurs at the upper part of the road, the roller and roller come into direct contact in the load area, and the direction of rotation is reversed at the contact point, generating a force that impedes rolling motion. The elastic spacer according to the invention can prevent such drawbacks.

In the present invention, a plurality of elastic spacers are inserted at equal intervals between rolling elements such as rollers in an endless circulation path consisting of a linear load track, a linear return path, and a direction change path connecting both ends of the path. This structure absorbs the gap between the rolling elements.

The present invention will be described in detail below with reference to the drawings.

In FIG. 4, structures of various elastic spacers are shown in (A) to (H), and these can be classified as follows.

(A) Fit the split elastic ring A2 into the fixed bottle A+.

(B) The fixing bottle B1 is inserted into the elastic ring B2, which has several slits in the circumferential direction to facilitate elastic deformation, and is fixed by caulking both ends or one end.

(C) A notch C2°G3 is provided at the center of the roller contact portion C1 to facilitate elastic deformation.

(D) A coiled spring D2 is wound around a fixed bottle D+.

(E) The fixed bottle E+ as shown in (A) is divided into two parts in the circumferential direction, and these parts are fixed by caulking with rivets E3, and the elastic ring E2 may be integrally formed.

(F) This is an improved version of (E), in which the tapered part of the fixed bin F+ supports the elastic ring F2 to eliminate looseness and reduce acoustics, and F3 is a rivet.

(G) This type is inserted into the circumferential gap for needle rollers, and has notches G2 and G3 in the axial direction on the surface of the contact portion G1 with the roller and other parts.

(H) For ball bearings, steel balls H1 are coated with an elastic material H2.

The above-mentioned elastic spacers can be categorized by use as follows.

The external dimensions of the elastic spacer for each of the above types are at most slightly smaller than the dimensions of the rolling elements, and the structure is such that it does not receive the bearing type even when passing through the load range.

(In the example of type a, the elastic members (elastic ring, elastic material, winding spring) are elastically deformed in the compression direction to absorb changes in the amount of movement in and out of the rolling elements, but excessive compressive force causes a load on the elastic members. When this occurs, the structure is such that the fixing member (fixing ring, steel ball) prevents the elastic member from deforming. (A,), (D)
, (E), there is a gap between the elastic member and the fixed member, and when moving linearly at high speed, noise and wear between the elastic member and the fixed member increase. In this case, (F) or (B)
The elastic member and the fixing member may be fixed together as shown in FIG.

Type (b) is inserted into the infinite circulation path so as to fill the circumferential gap between the rolling elements.For example, if there is a circumferential gap for one rolling element, (11) for 0.5 It is also possible to arrange two elastic spacers of the same type as 0.3 pieces (b
) Type elastic spacers may be arranged equally into three pieces. This type of structure simply fills the circumferential gap, so
A major feature is that the load capacity of the bearing does not decrease.
Rather, since the number of transferred objects within the track is stabilized, this has the effect of substantially increasing the load capacity.

FIGS. 5(A) and 5(B) show an example in which both types (a) and (b) of elastic spacers are used.

(A) is a longitudinal front view, and (B) is an explanatory view seen in the AA direction. Figure 5 (B) is similar to Figure 5 (A) -45
Figure 1.2 shows the case of 0, δ' and 45°. Cylindrical rollers 1 are approximately equal in diameter and length, and are arranged directly adjacent to each other alternately on an endless circulation path with their rotation axes 90 degrees apart, and the endless circulation path is linear and long. It consists of a load track 3 of length L, a linear return path 4, and a semicircular turning path 5.5 connecting both ends of both paths 3.4. Plastic elastic spacers A are inserted in place of the cylindrical rollers 1 at positions divided into three equal parts with approximately the same pitch as the length of the raceway. As a result, one in load area 3 and two in no-load area 4 and 5.
The amount of absorption becomes stable. In the case of the mouth, one C-shaped spacer is used and inserted into the circumferential gap. Note that only C-shaped spacers may be used, but in that case, tc is more stable if a plurality of spacers are arranged at equal pitches.

Figure 6 (A) is an actual measurement in which a roller bearing of the type shown in Figures 1 and 2 with δ' = 18° was placed in a horizontal position, filled with grease, and the sliding resistance was measured at a moving speed of 10 mm/sec. In the curves showing the values, the bold line is for a conventional bearing, and the curve is for a case with one C-shaped elastic spacer. Figure 6 (B) shows the same situation, but especially when stick-slip occurs at the entrance. This is an example using a device that is tilted and set so that it falls within the load range.

The effects of the present invention are as follows.

(1) As is clear from the measured curve in FIG. 6, the sliding resistance is clearly reduced by inserting the elastic spacer. The characteristic of this reduction is that it smoothes out the intermittent rapid decrease in sliding resistance, which is called stick-slip, by buffering it.

(2) In the case of vertical use with linear movement in the vertical direction, particularly large stick-slip was noticeable when moving from top to bottom, but with the implementation of the present invention, this reduction is no longer possible and even with vertical use It can be fully effective.

[Brief explanation of drawings]

Figure 1 is a partially cutaway front view showing one embodiment of a linear motion roller bearing, Figure 2 is a partially cutaway side view, and Figure 3 (A).
, (B), and (C) are perspective views, partially cutaway front views, and main part perspective views showing other embodiments of linear motion roller bearings, and FIG.
) to (H) are respectively perspective views or partially cutaway front views showing one example of implementing the present invention, and Figures 5 (A> and (B) are partial cross-sectional views of a linear motion roller bearing implementing the present invention). , an explanatory diagram viewed in the A-A direction, and FIGS. 6(A) and 6(B) are curve diagrams showing actual measurement results. The symbols in the figures indicate the following members, respectively. 1: Roller 2: Endless circulation path 3: Load track 4: Return path 52 Direction change path 6: Track rail 7: Casing 11: Track base 12: Guide plate 13: Stepped rollers (A) to (H) 2 Elastic spacer patent applicant Nippon Thomson Co., Ltd. E 1 Fig. 2 Fig. 3 Fig. 24 (A) (G) (1-1) Fig. 5 (A) Fig. O 6

Claims (1)

[Claims] 1. Insert one piece or equally spaced between rolling elements such as rollers in an endless circulation consisting of a linear load track, a linear return path, and a direction change path connecting both ends of the track. An elastic spacer for a rolling bearing for infinite linear motion, comprising a plurality of elastic spacers. 2. The elastic spacer is formed by attaching an elastic body with a slightly smaller outer diameter to the outer periphery of a fixed bottle having the same length as the rolling element, and is used in place of the rolling element. Elastic spacer for rolling bearings for infinite linear motion as described. 3. The elastic spacer has the same length as the rolling element and has a contact part with a shape compatible with the rolling element and an appropriate notch, so that the gap between the rolling elements is filled by dividing it into one or more equal parts. An elastic spacer for a rolling bearing for infinite linear motion according to claim 1.