CN211009576U

CN211009576U - Ball spline

Info

Publication number: CN211009576U
Application number: CN201921838143.4U
Authority: CN
Inventors: 蔡宗宪; 陈明峰
Original assignee: Hiwin Technologies Corp
Current assignee: Hiwin Technologies Corp
Priority date: 2019-10-29
Filing date: 2019-10-29
Publication date: 2020-07-14
Anticipated expiration: 2029-10-29

Abstract

A ball spline comprises a spline shaft and a nut, wherein the nut protrudes from a first boss on the inner ring surface of the spline shaft. The retainer is sleeved on the spline shaft and provided with second bosses, and the second bosses and the first bosses are arranged in a staggered mode and protrude out of the first bosses. And rolling members circulating between the nut, the spline shaft and the retainer. And the dustproof sheet is sleeved on the spline shaft and positioned at two sides of the retainer. The dustproof sheet protrudes out of the positioning parts, and the positioning parts are respectively arranged between the second bosses. Therefore, the positioning parts are respectively arranged between the second bosses, so that the rotation of the dustproof sheet relative to the spline shaft can be limited, the deviation of the dustproof sheet is reduced, and the assembly efficiency of the dustproof sheet is improved.

Description

Ball spline

Technical Field

The utility model relates to a linear transmission especially relates to a ball spline.

Background

A conventional ball spline, such as taiwan patent No. M558856, comprises a spline shaft, a nut, a retainer, a plurality of balls, two dust-proof elements and two retaining rings. The nut is sleeved on the spline shaft, and the retainer is arranged between the spline shaft and the nut and matched with the nut and the ball groove to enable the balls to circulate inside. In the nut, two sides of the retainer are respectively covered with dustproof elements, and the dustproof elements are limited in the nut through a limiting ring.

However, the dust-proof element in the aforementioned design still has a place to be improved. Firstly, the dustproof convex part of the dustproof sheet extends into the ball groove of the spline shaft, and if the dustproof convex part is deviated in the installation process of the dustproof element, the dustproof convex part can rub with the spline shaft in the ball groove and apply force to the spline shaft, so that abnormal resistance is generated on the spline shaft, and the dustproof element has the defect of difficult installation. In addition, the dustproof convex part of the dustproof element protrudes out of the binding surface in the axial direction, so that a limit ring without a buckle lug can be adopted to dodge the periphery of the dustproof convex part and be embedded into the nut, however, the buckle ring is inconvenient to mount or dismount, and the assembly efficiency of the dustproof element is reduced.

SUMMERY OF THE UTILITY MODEL

A primary object of the present invention is to provide a ball spline, which can improve the assembling efficiency of a dustproof member and prevent the deviation of a dustproof convex portion after the assembly of the dustproof member.

The foundation the utility model provides a ball spline contains: a spline shaft; the nut is sleeved on the spline shaft and provided with an inner ring surface, and a plurality of first bosses protrude from the inner ring surface; the retainer is sleeved on the spline shaft and positioned between the spline shaft and the nut, the retainer is provided with a plurality of second bosses, and each second boss and each first boss are arranged in a staggered mode and protrude out of each first boss; a plurality of rolling members that circulate among the nut, the spline shaft, and the retainer; the dustproof sheets are sleeved on the spline shaft and positioned on two sides of the retainer; the method is characterized in that: the dustproof sheet protrudes out of a plurality of positioning parts, and each positioning part is respectively arranged between the second bosses.

Therefore, the positioning parts are respectively arranged between the second bosses, the rotation of the dustproof sheet relative to the spline shaft can be limited, the deviation of the lip of the dustproof sheet is reduced, and the assembly efficiency of the dustproof sheet can be improved through the positioning parts.

It is worth mentioning that each positioning part can be abutted against each second boss respectively. Thereby enhancing the positioning stability of the dustproof sheet.

In addition, if the dust-proof sheet has an outer ring and an inner ring, the outer ring is disposed on the ball retainer, the inner ring is stacked on the outer ring, each positioning portion is formed on the outer ring, and each lip is formed on the inner ring. The inner ring body is formed with a first recess, a second recess and a third recess connected inwardly on opposite sides of each of the lips. The shortest distance between the first concave part and the axle center is a first distance; the shortest distance between the second concave part and the axis is a second distance; the shortest distance between the third concave part and the axle center is a third distance; the ball spline also comprises a plurality of C-shaped retaining rings, two ends of the screw cap respectively form a ring groove, each C-shaped retaining ring is clamped in each ring groove of the screw cap respectively, and the minimum diameter of the inner circumference when each C-shaped retaining ring is embedded into each ring groove of the screw cap is the inner diameter of the retaining ring; the second distance is less than half of the inner diameter of the retaining ring; the first distance and the third distance are less than half of the inner diameter of the retaining ring and greater than the second distance. When the C-shaped retaining ring is assembled, the first concave part, the second concave part and the third concave part are arranged to avoid buckling lugs of the C-shaped retaining ring, so that the C-shaped retaining ring is prevented from interfering the dustproof sheet.

It should be noted that the bottom of the first concave portion, the second concave portion or the third concave portion is a plane, so that the processing is more efficient.

It should also be noted that the lips are adjacent to each other along the inner ring at a long distance and a short distance, the second recess is located between the short distances, or the second recess is located between the long distances. The design can both achieve the effect of avoiding the buckling lug of the C-shaped buckle ring and further avoiding the C-shaped buckle ring from interfering the dustproof sheet.

Preferably, the spline shaft has a plurality of first rolling grooves extending along an axis, each first boss has a plurality of second rolling grooves, the retainer has a plurality of third rolling grooves between the second bosses, each third rolling groove penetrates the retainer, each third rolling groove forms a load path with the first rolling groove and the second rolling groove, the retainer has a plurality of backflow grooves at each second boss, each backflow groove is communicated with each third rolling groove, the load path and the backflow grooves form a circulation path for the rolling members to circulate, each dust-proof sheet protrudes a plurality of lips, and each lip protrudes into each first rolling groove.

Drawings

FIG. 1 is a perspective view of a preferred embodiment of the present invention;

fig. 2 is an exploded perspective view of the preferred embodiment of the present invention;

FIG. 3 is a partial perspective view of the preferred embodiment of the present invention, showing the situation without spline shaft;

FIG. 4 is a partial side view of the preferred embodiment of the invention showing the nut and retainer;

FIG. 5 is a cross-sectional view of the preferred embodiment of the present invention, showing the internal structure of the nut;

FIG. 6 is a partial side view of the preferred embodiment of the present invention showing the arrangement of the dust guard and the C-shaped retaining ring;

FIG. 7 is a partial perspective view of the preferred embodiment of the present invention showing the second recess between the long spaces;

fig. 8 is a partial perspective view of the preferred embodiment of the present invention, showing the second recess between the short spaces.

[ description of reference ]

10 ball spline

11 spline shaft 111 first rolling groove

12 nut 121 inner ring surface

122 first boss 123 second rolling groove

124 ring groove 13 holder

131 second boss 132 third rolling groove

133 return groove 134 guide part

15 dust-proof piece 15a outer ring body

15b inner ring 151 lip

152 position part 153 first recess

154 second recess 155 third recess

16C type retaining ring 161 fastening ear

Long distance between axis A and L

S short pitch P load path

D1 first distance D2 second distance

D3 third distance D4 inner diameter of retaining ring

Detailed Description

For the purpose of illustrating the technical features of the present invention in detail, the following preferred embodiments are illustrated in the accompanying drawings, wherein:

as shown in fig. 1-8, a ball spline 10 according to a preferred embodiment of the present invention includes a spline shaft 11, a nut 12, a retainer 13, a plurality of rolling members (not shown), a plurality of dust-proof pieces 15, and a plurality of C-shaped retaining rings 16.

The spline shaft 11 has a plurality of first rolling grooves 111 extending along an axial center a.

The nut 12 is disposed around the spline shaft 11, the nut 12 has an inner annular surface 121, a plurality of first bosses 122 protrude from the inner annular surface 121 of the nut 12, each of the first bosses 122 has a plurality of second rolling grooves 123, and two ends of the nut 12 form an annular groove 124.

Please refer to fig. 2, 3 and 4. The retainer 13 is sleeved on the spline shaft 11 and located between the spline shaft 11 and the nut 12, the retainer 13 has a plurality of second bosses 131, and each second boss 131 and each first boss 122 are staggered and protrude from each first boss 122. The retainer 13 has a plurality of third rolling grooves 132 between the second bosses 131, each of the third rolling grooves 132 penetrates the retainer 13, and each of the third rolling grooves 132 forms a load path P with the first rolling groove 111 and the second rolling groove 123, respectively. The retainer 13 has a plurality of return grooves 133 in the second bosses 131, and the return grooves 133 communicate with the third rolling grooves 132, respectively. The retainer 13 has a guiding portion 134 protruding inward at the junction of each backflow groove 133 and each third rolling groove 132, and each guiding portion 134 extends into the first rolling groove 111 of the spline shaft 11 to guide the operation direction of the rolling elements.

The rolling members (not shown) are disposed in the third rolling groove 132 and the return groove 133, and the load path and the return grooves 133 form a circulation path for the rolling members to circulate.

Referring to fig. 1, each dust-proof sheet 15 is sleeved on the spline shaft 11 and located at two sides of the retainer 13, each dust-proof sheet 15 protrudes from a plurality of lips 151, and each lip 151 extends into each first rolling groove 111 to block dust or foreign matters from entering the nut 12 and the retainer 13.

Each C-shaped retaining ring 16 has a retaining lug 161 at each end thereof for being engaged in the annular groove 124 of the nut 12 to prevent the retainer 13 and the dust-proof pieces 15 from falling off the nut 12.

The present embodiment is characterized in that: the dust-proof sheet 15 has a plurality of positioning portions 152 protruding therefrom, and each of the positioning portions 152 is disposed between the second bosses 131.

The positioning parts 152 are respectively arranged between the second bosses 131, so that the rotation of the dust-proof sheet 15 relative to the spline shaft 11 can be limited to reduce the deviation of the lip 151 of the dust-proof sheet 15, and further, the situation that the lip 151 exerts force on the spline shaft 11 in the first rolling groove 111 to generate thrust to hinder the operation of the spline shaft 11 is avoided, and the assembly efficiency of the dust-proof sheet can be improved through the positioning parts.

In addition, each positioning portion 152 can be abutted against each second boss 131, so as to enhance the positioning stability of the dust-proof sheet 15 by applying force to each second boss 131.

It should be noted that, in the present embodiment, the dust-proof sheet 15 has an outer ring body 15a and an inner ring body 15b, the outer ring body 15a is disposed on the retainer 13, the inner ring body 15b is stacked on the outer ring body 15a, each positioning portion 152 is formed on the outer ring body 15a, and each lip portion 151 is formed on the inner ring body 15 b.

Please refer to fig. 6-8. The inner ring 15b has a first recess 153, a second recess 154 and a third recess 155 on opposite sides of each lip 151. The shortest distance between the first concave portion 153 and the axis a is a first distance D1. The shortest distance between the second recess 154 and the axis A is a second distance D2. The shortest distance between the third concave portion 155 and the axis a is a third distance D3. It should be noted that the minimum diameter of the inner circumference when the C-shaped retaining ring 16 is inserted into the nut 12 is a retaining ring inner diameter D4. The second distance D2 is less than half of the retaining ring inner diameter D4. The first distance D1 and the third distance D3 are less than half of the retaining ring inner diameter D4 and greater than the second distance D2. It should be noted that, in the present embodiment, the bottom of the first concave portion 153, the second concave portion 154 or the third concave portion 155 is flat, so that the processing is more efficient.

When the C-shaped retaining ring 16 is assembled, the first concave portion 153, the second concave portion 154 and the third concave portion 155 are disposed to avoid the retaining lug 161 of the C-shaped retaining ring 16, so as to prevent the assembled C-shaped retaining ring 16 from interfering with the dust-proof piece 15.

Referring also to fig. 7 and 8, the second recesses 154 are positioned between the short spacings S or the second recesses 154 are positioned between the long spacings S L along the lips 151 of the inner ring 15b adjacent to each other at a long spacing L and a short spacing S, which can avoid the ears 161 of the C-ring 16 and reduce the interference of the C-ring 16 with the dust-guard 15 after assembly.

The above-mentioned embodiments, further detailed description of the objects, technical solutions and advantages of the present invention, it should be understood that the above-mentioned embodiments are only specific embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A ball spline comprises a spline shaft; the nut is sleeved on the spline shaft and provided with an inner ring surface, and a plurality of first bosses protrude from the inner ring surface; the retainer is sleeved on the spline shaft and positioned between the spline shaft and the nut, the retainer is provided with a plurality of second bosses, and the second bosses and the first bosses are arranged in a staggered manner; a plurality of rolling members that circulate among the nut, the spline shaft, and the retainer; the dustproof sheets are sleeved on the spline shaft and positioned on two sides of the retainer; the method is characterized in that:

the dustproof sheet protrudes out of a plurality of positioning parts, and each positioning part is respectively arranged between the second bosses.

2. The ball spline of claim 1, wherein: each positioning part is respectively propped against each second boss.

3. The ball spline of claim 1, wherein: the dustproof sheet is provided with an outer ring body and an inner ring body, the outer ring body is arranged on the ball retainer, the inner ring body is overlapped on the outer ring body, each positioning part is formed on the outer ring body, and each lip part is formed on the inner ring body; the inner ring body is provided with a first concave part, a second concave part and a third concave part which are connected at the opposite sides of each lip part; the shortest distance between the first concave part and the axle center is a first distance; the shortest distance between the second concave part and the axis is a second distance; the shortest distance between the third concave part and the axle center is a third distance; the ball spline also comprises a plurality of C-shaped retaining rings, two ends of the screw cap respectively form a ring groove, each C-shaped retaining ring is clamped in each ring groove of the screw cap respectively, and the minimum diameter of the inner circumference when each C-shaped retaining ring is embedded into each ring groove of the screw cap is the inner diameter of the retaining ring; the second distance is less than half of the inner diameter of the retaining ring; the first distance and the third distance are less than half of the inner diameter of the retaining ring and greater than the second distance.

4. The ball spline of claim 3, wherein: the bottom of the first concave part, the second concave part or the third concave part is a plane.

5. The ball spline of claim 3, wherein: the lips are adjacent to each other along the inner ring at a long distance and a short distance, and the second recess is located between the short distances.

6. The ball spline of claim 3, wherein: the lips are adjacent to each other along the inner ring at a long distance and a short distance, and the second recess is located between the long distances.

7. The ball spline of claim 1, wherein: the spline shaft is provided with a plurality of first rolling grooves extending along a shaft center, each first boss is provided with a plurality of second rolling grooves, the retainer is provided with a plurality of third rolling grooves between the second bosses, each third rolling groove penetrates through the retainer, each third rolling groove and the first rolling groove and the second rolling groove form a load path, the retainer is provided with a plurality of backflow grooves at each second boss, each backflow groove is communicated with each third rolling groove, the load path and the backflow grooves form a circulating path for each rolling element to circularly flow, each dustproof sheet protrudes out of a plurality of lips, and each lip extends into each first rolling groove.