JP2018138816A - Linear motion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a linear motion device capable of fixing a rolling body holder to an outer cylinder in a one-touch way without using another fixing member, only by inserting the rolling body holder to the outer cylinder.SOLUTION: A linear motion device comprises a shaft 1, an outer cylinder 2 fitted to the shaft 1, a rolling body holder 3 provided between the shaft 1 and the outer cylinder 2, and a rolling body 4 held by the rolling body holder 3, wherein between the outer cylinder 2 and the shaft 1, provided is a rolling body endless circulation part 8 comprising a load part, a non-load part and a return part connecting between the load part and the non-load part. At both end parts of the rolling body holder 3, provided is a claw part 7 capable of bendingly deforming on the shaft 1 side in inserting into the outer cylinder 2. At the claw part 7, provided is a convex part 6 provided on an inner peripheral surface of the outer cylinder 2 and fitted into a concave part 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a linear motion device.

  Linear motion device (linear) comprising a shaft, an outer cylinder fitted to the shaft, a rolling element holder provided between the shaft and the outer cylinder, and a rolling element (ball) held by the rolling element holder Bush and ball spline).

  By the way, as disclosed in, for example, Patent Document 1, a rolling element retainer has conventionally used an outer cylinder using a C-shaped retaining ring (snap ring) that is engaged with a groove at an inner peripheral end of the outer cylinder. The structure which fixes to is common, and the components for fixation other than an outer cylinder and a rolling-element holder are required.

JP 2001-343019 A

  The present invention has been made in view of the above-described situation, and by simply inserting the rolling element holder into the outer cylinder, the rolling element holder can be fixed to the outer cylinder with one touch without using other fixing members. A periodical linear motion apparatus is provided.

  The gist of the present invention will be described with reference to the accompanying drawings.

  A shaft 1, an outer cylinder 2 fitted on the shaft 1, a rolling element holder 3 provided between the shaft 1 and the outer cylinder 2, and a rolling element held by the rolling element holder 3 4 and between the outer cylinder 2 and the shaft 1, there is provided a rolling element infinite circulation portion 8 comprising a load portion, a no-load portion, and a return portion connecting the load portion and the no-load portion. In each of the linear motion devices, claw portions 7 that can be bent and deformed on the shaft 1 side when inserted into the outer cylinder 2 are provided at both ends of the rolling element holder 3, respectively. Reference numeral 7 denotes a linear motion device characterized in that a convex portion 6 that fits into a concave portion 5 provided on the inner peripheral surface of the outer cylinder 2 is provided.

  The linear motion device according to claim 1, wherein a plurality of the claw portions 7 are provided at both ends of the rolling element holder 3, respectively.

  Further, in the linear motion device according to any one of claims 1 and 2, the claw portions 7 are provided at both ends of the rolling element holder 3 by a number equal to or less than the number of the rolling element infinite circulation portions 8 installed. The present invention relates to a linear motion device.

  Moreover, the linear motion apparatus of any one of Claims 1-3 WHEREIN: The said nail | claw part 7 is provided in the position shifted | deviated from the position on the longitudinal direction extension line of the said load part, The linear motion characterized by the above-mentioned. It concerns the device.

  5. The linear motion device according to claim 1, wherein when the claw portion 7 is inserted into the outer cylinder 2, the claw portion 7 bends and deforms toward the shaft 1 and moves back in the recess 5. The convex portion 6 fits into the concave portion 5 and relates to a linear motion device.

  Further, in the linear motion device according to any one of claims 1 to 5, the rolling element holder 3 is made of a synthetic resin, and the claw portion 7 is provided integrally with the rolling element holder 3. The present invention relates to a linear motion device characterized by being made of synthetic resin.

  Further, in the linear motion device according to any one of claims 1 to 6, when the rolling element holder 3 is inserted into the outer cylinder 2 at the outer side position of the convex portion 6, the outer cylinder 2 is provided with an inclined surface 9 abutting on the inner peripheral surface, and a rising engagement surface 10 is provided on the opposite side of the inclined surface 9 at the position on the inner side of the convex portion 6 to be engaged with the concave portion 5. The present invention relates to a linear motion device.

  Since the present invention is configured as described above, it is an epoch-making linear motion that allows the rolling element holder to be fixed to the outer cylinder with one touch without using any other fixing member by simply inserting the rolling element holder into the outer cylinder. It becomes a device.

It is a schematic explanatory perspective view of a present Example. It is a schematic explanatory perspective view of the outer cylinder and rolling element holder of a present Example. It is a schematic explanatory sectional drawing explaining the load part etc. of a present Example. It is an expansion outline explanatory sectional view of a claw part of this example. It is a schematic explanatory perspective view of another example.

  An embodiment of the present invention which is considered to be suitable will be briefly described with reference to the drawings showing the operation of the present invention.

  When attaching the rolling element holder 3 to the outer cylinder 2, the rolling element holder 3 is simply inserted by inserting the rolling element holder 3 into the outer cylinder 2 and fitting the projection 6 of the claw 7 into the corresponding recess 5. It can be fixed to the outer cylinder 2. That is, even if the convex portion 6 contacts the inner peripheral surface of the outer cylinder 2, the claw portion 7 is bent and deformed to the shaft 1 side and the insertion is not hindered, and when the convex portion 6 reaches the position of the concave portion 5, the claw portion 7 returns and the convex part 6 fits into the concave part 5. Therefore, it is possible to easily fix the rolling element holder 3 to the outer cylinder 2 with one touch without using other members than the outer cylinder 2 and the rolling element holder 3.

  Specific embodiments of the present invention will be described with reference to the drawings.

  In this embodiment, a shaft 1, an outer cylinder 2 fitted on the shaft 1, a rolling element holder 3 provided between the shaft 1 and the outer cylinder 2, and the rolling element holder 3 The rolling element 4 is held between the outer cylinder 2 and the shaft 1 and includes a load part, a no-load part, and a return part that connects the load part and the no-load part. It is a linear motion device provided with a circulating portion 8, and claw portions 7 that can be bent and deformed on the shaft 1 side when inserted into the outer cylinder 2 are provided at both ends of the rolling element holder 3, respectively. The claw portion 7 is provided with a convex portion 6 that fits into a concave portion 5 provided on the inner peripheral surface of the outer cylinder 2.

  The present embodiment is a linear bush as illustrated in FIG. 1, and the rolling element retainer 3 is provided with four rolling element infinite circulation portions 8.

  The outer cylinder 2 is made of metal, and its inner surface shape is set to a shape that matches the outer surface shape of the rolling element holder 3 in order to prevent the rolling element holder 3 from rotating. An annular groove 11 is formed on the inner peripheral surface of the outer cylinder 2 at a predetermined length from the end surfaces of both ends (see FIGS. 2 and 3). The annular groove 11 constitutes a recess 5 that fits with the protrusion 6.

  The rolling element holder 3 is made of synthetic resin, and as shown in FIG. 2, a long window-shaped load groove 12 in which the rolling elements 4 constituting the load portion are disposed, and an unloaded portion that forms an unloaded portion. Four sets of the groove 13 and the return groove 14 constituting the return portion connecting the load portion and the no-load portion are formed. Specifically, the load portion is composed of the load portion constituting portion 15 on the inner peripheral surface of the outer cylinder 2, the load groove 12, and the outer peripheral surface of the shaft 1. The no-load portion is composed of the no-load groove 13 and the inner peripheral surface of the outer cylinder 2. The return portion is constituted by the return groove 14 and the inner peripheral surface of the outer cylinder 2.

  The load part and the no-load part are arranged substantially in parallel, and a racetrack-like rolling element infinite circulation part 8 is formed by connecting both ends of the both parts with a return part.

  The rolling element holder 3 has a rounded rectangular tube shape with no straight portion on the outer periphery in a sectional view. Specifically, the rolling element cage 3 has an outer surface shape in which R-shaped corner portions are connected by side portions that draw a loose arc in a cross-sectional view, and the inner surface shape of the outer cylinder 2 is for positioning corresponding to each corner portion. The shape is formed with a recess.

  Claw portions 7 are provided at both ends of the rolling element holder 3 at equal intervals in the circumferential direction. Specifically, the claw portions 7 are respectively provided at the four corner portions at both ends. The claw portion 7 protrudes outward in substantially parallel to the axial direction of the rolling element holder 3. The claw portion 7 is integrally formed when the rolling element holder 3 is molded. Further, when the claw portion 7 is inserted into the outer cylinder 2, elasticity or the like is set so that the claw portion 7 bends and deforms toward the shaft 1, moves back in the concave portion 5, and the convex portion 6 fits into the concave portion 5. In the figure, reference numeral 16 denotes a groove that partitions the claw portion 7.

  On the upper surface of the claw part 7, a convex part 6 rising in the direction perpendicular to the axis is provided. As shown in FIG. 4, when the rolling element holder 3 is inserted into the outer cylinder 2, the convex part 6 abuts on the inner peripheral surface of the outer cylinder 2 (facing the outer side). ) An inclined surface 9 is provided. In addition, a rising locking surface 10 that rises substantially vertically (facing the inner side) to be locked to the concave portion 5 is provided on the opposite side of the inclined surface 9 at the inner side position of the convex portion 6. Therefore, the nail | claw part 7 can be bent smoothly at the time of insertion, and the latching fixation with the recessed part 5 is performed reliably. In the figure, reference numeral 17 denotes a fitting guide taper part for guiding the fitting of the convex part 6 to the concave part 5, and 18 denotes a notch part for facilitating deformation of the tip of the claw part 7.

  Therefore, when the rolling element holder 3 is inserted into the outer cylinder 2, if the convex part 6 is pressed against the inner peripheral surface of the outer cylinder 2, the claw part 7 is bent toward the shaft 1 side by the elasticity of the synthetic resin. When the deformation is completed and the insertion is completed and the positions of the convex portion 6 and the concave portion 5 coincide with each other, the convex portion 6 is fitted into the concave portion 5 and attached to the outer cylinder 2.

  In the present embodiment, a plurality of claw portions 7 are provided at both ends of the rolling element holder 3. Specifically, it is preferable to provide at least a pair of diagonal positions across the shaft 1. In this case, the rolling element holder 3 can be fixed to the outer cylinder 2 more stably.

  In the present embodiment, the same number of claw portions 7 as the number of rolling element infinite circulation portions 8 are provided. The number of the claw portions 7 can be set as appropriate. For example, by setting the number of the claw portions 7 to be the same as that of the rolling element infinite circulation portion 8, a necessary and sufficient amount of the claw portions 7 are arranged in a balanced manner without reducing the strength of the rolling element cage 3 It becomes possible to do.

  Moreover, the nail | claw part 7 is provided in the position shifted | deviated from the position on the longitudinal direction extension line of a load part. The load portion constituting portion 15 on the inner peripheral surface of the outer cylinder 2 sandwiches the rolling element 4 disposed in the load groove 12 between the outer cylinder 2 and the shaft 1 as shown in FIG. The transfer path rises one step toward the shaft 1 side. Accordingly, if the claw portion 7 is positioned on the longitudinal extension line of the load portion, it is necessary to greatly bend and deform toward the shaft 1 side when the claw portion 7 passes through the load portion constituting portion 15, and this bending deformation is obstructed. In addition, the elasticity of the claw portion 7 needs to be set precisely so that the locking to the concave portion 5 is reliably performed.

  In this respect, in this embodiment, by providing the claw portion 7 at a position shifted from the position on the longitudinal extension line of the load portion, it is not necessary to pass the claw portion 7 through the load portion constituting portion 15 (of the outer cylinder 2). The transfer path that rises one step on the inner peripheral surface is not greatly bent and deformed toward the shaft 1 side), and can pass the portion with the least amount of bending deformation toward the shaft 1 as much as possible. Even if it is not set precisely, it is possible to realize the claw portion 7 that can be bent and deformed well on the shaft 1 side during insertion and that can firmly lock the convex portion 6 to the concave portion 5.

  Moreover, it is good also as a structure which provides the sealing member for preventing the penetration | invasion of the dust to the rolling element infinite circulation path 8 in the end surface of the rolling element holder | retainer 3. FIG.

  Although the present embodiment describes the case of a linear bush, as in another example illustrated in FIG. 5, the present invention includes a rolling element disposition groove 19 in which the rolling element 4 is disposed on the shaft 1. The present invention can be similarly applied to a so-called ball spline formed. As described above, the installation location and the number of installation of the claw portions 7 can be set as appropriate. In FIG. 5, the claw portions 7 are provided at two left and right positions on both ends of the rolling element holder.

  Since the present embodiment is configured as described above, when the rolling element holder 3 is attached to the outer cylinder 2, the rolling element holder 3 is inserted into the outer cylinder 2, and the protrusion 6 of the claw portion 7 is made to correspond to the corresponding recess 5. The rolling element retainer 3 can be fixed to the outer cylinder 2 simply by fitting to the outer cylinder 2. That is, even if the convex portion 6 contacts the inner peripheral surface of the outer cylinder 2, the claw portion 7 is bent and deformed to the shaft 1 side and the insertion is not hindered, and when the convex portion 6 reaches the position of the concave portion 5, the claw portion 7 returns and the convex part 6 fits into the concave part 5.

  Therefore, in this embodiment, the rolling element holder can be fixed with one touch without using other fixing members simply by inserting the rolling element holder into the outer cylinder.

DESCRIPTION OF SYMBOLS 1 axis | shaft 2 outer cylinder 3 rolling element holder | retainer 4 rolling element 5 recessed part 6 convex part 7 claw part 8 rolling element infinite circulation part 9 inclined surface
10 Standing locking surface

Claims (7)

  The outer cylinder includes a shaft, an outer cylinder fitted to the shaft, a rolling element holder provided between the shaft and the outer cylinder, and a rolling element held by the rolling element holder. A linear motion apparatus provided with a rolling element infinite circulation part comprising a load part, a no-load part, and a return part that connects the load part and the no-load part, respectively, between the shaft and the shaft. Claw portions that can be bent and deformed on the shaft side when inserted into the outer cylinder are respectively provided at both ends of the moving body retainer, and the claw portions are provided in recesses provided on the inner peripheral surface of the outer cylinder. A linear motion device characterized in that a convex portion to be fitted is provided.   2. The linear motion device according to claim 1, wherein a plurality of the claw portions are provided at both ends of the rolling element holder.   The linear motion device according to any one of claims 1 and 2, wherein the claw portions are provided at both ends of the rolling element retainer by a number equal to or less than the number of the rolling element infinite circulation portions. A linear motion device characterized.   The linear motion device according to any one of claims 1 to 3, wherein the claw portion is provided at a position shifted from a position on a longitudinal extension line of the load portion.   5. The linear motion device according to claim 1, wherein when the claw portion is inserted into the outer cylinder, the claw portion bends and deforms toward the shaft side and moves back in the concave portion so that the convex portion is the concave portion. A linear motion device characterized by being fitted to the body.   6. The linear motion device according to claim 1, wherein the rolling element retainer is made of a synthetic resin, and the claw portion is made of a synthetic resin provided integrally with the rolling element retainer. A linear motion device characterized by being.   The linear motion device according to any one of claims 1 to 6, wherein when the rolling element retainer is inserted into the outer cylinder at an outer side position of the convex portion, an inner peripheral surface of the outer cylinder is inserted. A linear motion device characterized in that an abutting inclined surface is provided, and a rising engagement surface that is engaged with the concave portion is provided on an opposite side of the inclined surface at an inward position of the convex portion.

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