TW201634832A - Ball screw device and bearing bush assembly thereof - Google Patents

Abstract

A bearing bush assembly of a ball screw device is disclosed. The bearing bush assembly is mounted on the screw and includes two bearing bushes, an annular locating element and a preloading regulating element. Each of the bearing bushes respectively has a inner locating groove and a inner ball groove. The inner ball grooves are disposed corresponding to a plurality of outer ball groove. The annular locating elements are respectively disposed between the bearing bushes, and the annular locating element is accommodated in the inner locating groove. The preloading regulating element is disposed between the bearing bushes. The present invention also discloses a ball screw device.

Description

Ball screw device and its bearing sleeve assembly

The present invention relates to a ball screw device and a bearing sleeve assembly therefor.

Rotary ball screw is a device widely used in many mechanical devices. Its main purpose is to provide precise transmission function. In the mechanical operation, the rotary motion and linear motion can make the loaded machine or object in a straight line. Act on it.

In the rotary ball screw of the prior art, a screw, a nut, a plurality of balls, and a bearing sleeve are mainly included. The surface of the screw has a spiral groove, and the inner surface of the nut also has a spiral inner groove to form a first ball passage with the screw. The bearing sleeve is disposed on the outer circumference of the nut, and the outer surface of the nut has an outer ball groove and forms a second ball passage with the inner ball groove of the bearing sleeve. The first ball channel and the second ball channel are provided with a plurality of balls. The balls can respectively assist the nut and the screw, and the relative rotation of the bearing sleeve and the nut, so that the mechanical components carried by the rotary ball screw can be linearly moved along the axial direction of the screw, and also because the rotary ball screw is simultaneously realized. The movement behavior of rotation and linear movement provides two different setting options: the screw is not fixed, the nut is fixed, or the nut is not fixed, and the screw is fixed.

However, in the ball cage currently set in the bearing sleeve, there are several circular holes, which are the positioning holes for fixing the rolling steel ball, and the wire cutting and CNC milling machine are used for processing the metal foil such as aluminum alloy. production. However, in this manufacturing method, the four-axis numerical control CNC milling machine and the wire-cut electrical discharge machining are required in the process, the processing steps are complicated, and the manufacturing cost is high. Especially for configurations with inverted draft angle, CNC milling machines are difficult to machine, but if special tools are used for machining, additional costs are required, and for small-sized ball cages with small thickness, CNC milling machines are not easy to clip. Hold, easy to produce deformation, low yield. In addition, if the injection molding technology is used to make the plastic material, an additional radial moving slider is required, which is expensive. and Since the ball cage of the plastic material which is injection-molded has residual stress, the amount of deformation is large, and the yield of the product is also lowered. However, if the design needs to be changed in the case of customization, the tool cutting process needs to re-plan the tool cutting path or re-create the clamping tool, and if the injection molding method is used, the mold needs to be modified or even remanufactured. Both methods increase the cost required.

Therefore, how to provide a ball screw device and its bearing sleeve assembly can change the design and manufacture according to customer requirements without having to make a mold, a clamp, or a cutting process, and has become one of the important topics.

In view of the above problems, an object of the present invention is to provide a bearing sleeve assembly for a ball screw device, which is sleeved on a nut, and includes: two bearing sleeves respectively having an inner positioning groove and an inner ball groove. The ball groove is disposed corresponding to the plurality of outer ball grooves of the nut, so that each of the inner ball grooves and each of the outer ball grooves form a ball passage; an annular positioning member is sandwiched between the two bearing sleeves And the annular positioning component is received in the inner positioning groove; at least one ball retainer having an annular thin-walled body and being formed by lamination and sleeved on the nut and the Between the bearing sleeves, a plurality of retaining portions are disposed on the annular thin-walled body; a plurality of balls are received in the retaining portions and the ball passages, and the circumference of each of the retaining portions is not less than each of the retaining portions One-half of the circumference of the largest section of the ball, and a pre-stressing adjustment element are interposed between the two bearing sleeves.

In an embodiment, each of the retaining portions has a concave conical surface in a radial section.

In one embodiment, each of the retaining portions has a C-shaped recess, and each of the C-shaped recesses covers each of the balls at an angle greater than 180 degrees.

In one embodiment, each C-shaped notch covers each of the balls at an angle of from 200 degrees to 270 degrees.

In one embodiment, each C-shaped recess has a crowned top and a bottom, the radial thickness of the crowned top being greater than the radial thickness of the bottom.

In one embodiment, the multilayer manufacturing method is selected from the group consisting of: selective laser sintering (SLS), photocuring (Stereolithography apparatus, SLA), Ink jet printing (IJP), and Fused deposition modeling (FDM).

In one embodiment, the material of the ball cage is selected from the group consisting of nylon (Nylon), acrylonitrile-butadiene-styrene copolymer (ABS), carbon fiber reinforced plastic, carbon nanotube reinforced plastic, glass fiber reinforced plastic, A group consisting of polyfluorinated diethylene (PVDF), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), and polyimide (PI).

In one embodiment, the ball retainer is further added with zirconia powder, alumina powder, cerium oxide powder, aluminum nitride powder, tantalum nitride powder, tantalum carbide powder, carbon nanotube, carbon powder, glass fiber, carbon fiber. , strontium carbide fibers, or whiskers fibers.

Another object of the present invention is to provide a ball screw device comprising: a screw; a nut disposed on the screw, and a first ball passage between the nut and the screw, the outer surface of the nut having a plurality of first outer ball grooves; a plurality of first balls accommodated in the first ball passage; and a bearing sleeve assembly including: two bearing sleeves each having an inner positioning groove and an inner ball groove, The inner ball groove is disposed corresponding to the outer ball grooves of the nut, so that each inner ball groove and each outer ball groove form a second ball passage; an annular positioning member is sandwiched between the two bearings Between the sleeves, and the annular positioning member is received in the inner positioning groove; at least one ball retainer having an annular thin-wall body and being formed by lamination and sleeved on the nut And a plurality of retaining portions disposed between the bearing sleeves and the annular thin-walled body; the plurality of second balls are received in the retaining portions and the second ball passages, and the circumference of each retaining portion is not Less than each of the second balls housed therein The circumferential length of one-half the maximum cross-section, and a preload adjusting member interposed between the two bearing sleeves.

In an embodiment, each of the retaining portions has a concave conical surface in a radial section.

A further object of the present invention is to provide a ball screw device comprising: a screw; a nut disposed on the screw, and a first ball passage between the nut and the screw, the outer surface of the nut having a plurality of outer ball grooves; a plurality of first balls are received in the first ball passages; a bearing sleeve is sleeved on the nut, and an inner ball surface of the bearing sleeve is provided with at least one inner ball groove, the inner ball The groove and the corresponding outer ball groove form a second ball passage; at least one ball retainer having an annular thin-wall body and being formed by lamination and sleeved on the nut, and Providing a plurality of retaining portions on the annular thin-walled body; The beads are received in the holding portions and the second ball passages, and the circumference of each of the holding portions is not less than one-half of a circumference of a maximum cross section of each of the second balls housed therein.

In one embodiment, each of the retaining portions has a C-shaped recess, and each of the C-shaped recesses covers each of the second balls at an angle greater than 180 degrees.

In one embodiment, each C-shaped notch covers each of the second balls at an angle of from 200 degrees to 270 degrees.

In one embodiment, each C-shaped recess has a crowned top and a bottom, the radial thickness of the crowned top being greater than the radial thickness of the bottom.

In one embodiment, the multilayer manufacturing method is selected from the group consisting of: Selective laser sintering (SLS), Stereolithography apparatus (SLA), inkjet printing Ink jet printing (IJP), and Fused deposition modeling (FDM).

In one embodiment, the material of the ball cage is selected from the group consisting of nylon (Nylon), acrylonitrile-butadiene-styrene copolymer (ABS), carbon fiber reinforced plastic, carbon nanotube reinforced plastic, glass fiber reinforced plastic, A group consisting of polyfluorinated diethylene (PVDF), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), and polyimide (PI).

In one embodiment, the ball retainer is further added with zirconia powder, alumina powder, cerium oxide powder, aluminum nitride powder, tantalum nitride powder, tantalum carbide powder, carbon nanotube, carbon powder, glass fiber, carbon fiber. , strontium carbide fibers, or whiskers fibers.

As described above, the ball screw device and the bearing sleeve assembly of the present invention are manufactured by a laminated manufacturing method because the ball retainer has an annular thin-walled body, compared with the conventional CNC milling machine and wire-cut electrical discharge machining. The processing method has a high yield. At the same time, the circumference of the plurality of retaining portions provided on the annular thin-walled body is not less than one-half of the circumferential length of the largest section of each of the balls accommodated therein, and has a tilting mode configuration. When machining with conventional tools or injection molding, special tools or additional design of radially moving sliders are required, which is expensive. However, the present invention is produced by a laminate manufacturing (3D printing) method, and the ball holder having the inverted mold inclination configuration can be directly produced, so that the cost is low.

In addition, since the ball retainer of the present invention can be made of a plastic resin material, it has the advantages of light weight, low noise, good lubricity and the like.

1, 2‧‧‧ ball screw device

11, 21‧‧‧ screw

111, 211‧‧‧ spiral groove

12, 22‧‧‧ nuts

121, 221‧‧‧ outer ball groove

123, 222‧‧‧ first inner ball groove

122‧‧‧through hole

13a, 13b, 23‧‧‧ bearing sleeves

131a, 131b, 231‧‧‧ second inner ball groove

Positioning groove in 132a, 132b‧‧

14, 24‧‧‧Ball retainers

141, 241‧‧‧ Holding Department

15‧‧‧Preloading adjustment components

16a, 26a‧‧‧second ball

16b, 26b‧‧‧ first ball

17‧‧‧Dust-proof parts

18‧‧‧End cover

19‧‧‧Ring positioning elements

213‧‧‧Circular passage

2411‧‧‧ crown top

2412‧‧‧ bottom

27‧‧‧Reflux components

271‧‧‧Reflux channel

28‧‧‧Dustproof components

281‧‧‧Dust-proof parts

2811‧‧‧Scratch

282‧‧‧Fixed parts

29‧‧‧Reinforcement

A-A‧‧‧ hatching

B‧‧‧bearing sleeve assembly

OS‧‧‧ outside surface

P‧‧‧Drive connector

P1‧‧‧First Ball Channel

P2‧‧‧second ball channel

RP‧‧‧Ball cycle

S1‧‧‧ screw hole

S2‧‧‧ screws

1A is a schematic view of a ball screw device according to an embodiment of the present invention.

Fig. 1B is an exploded perspective view of the ball screw device shown in Fig. 1A.

1C is a schematic cross-sectional view of the ball screw device shown in FIG. 1A.

Figure 1D is a schematic view of the ball retainer of the ball screw device shown in Figure 1A.

Figure 1E is a partially exploded perspective view of the ball screw device of Figure 1A.

2A is a schematic view of a ball screw device according to a second embodiment of the present invention.

2B is an exploded perspective view of the ball screw device shown in FIG. 2A.

2C is a schematic cross-sectional view of the ball screw device shown in FIG. 2A taken along line A-A.

2D is a schematic view of the ball retainer in the ball screw device shown in FIG. 2A.

2E and 2F are schematic views of another ball retainer in the ball screw device shown in Fig. 2A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a ball screw device according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings, wherein the same elements will be described with the same reference numerals.

1A is a schematic view of a ball screw device according to an embodiment of the present invention, and FIG. 1B is an exploded perspective view of the ball screw device shown in FIG. 1A. 1A and 1B, the ball screw device 1 includes a screw 11, a nut 12, two bearing sleeves 13a, 13b, an annular positioning member 19, a ball retainer 14, and a preload adjusting member 15. And a plurality of first balls 16b and a plurality of second balls 16a. The screw 11 is a cylindrical rod body, and its outer surface has a spiral groove 111 continuously wound along the longitudinal axis. The nut 12 is an annular cylinder having a plurality of outer ball grooves 121, and a through hole 122 is formed in the center of the nut 12, and the inner surface of the nut 12 adjacent to the through hole 122 has a first inner ball groove 123. The lead distance and the groove surface configuration of the first inner ball groove 123 are the same as or similar to the spiral groove 111 of the screw 11. When the nut 12 is sleeved on the screw 11 through the through hole 122, the spiral first inner ball groove 123 of the nut 12 and the spiral groove 111 of the screw 11 can correspond to each other to form a first ball passage. . The plurality of first balls 16b are accommodated in the first ball passage.

1A, 1B, and 1D, wherein FIG. 1D is a diagram A schematic view of the ball cage 14 of the ball screw device shown in Fig. 1A. The ball retainer 14 has an annular thin-walled body and is formed by a laminated manufacturing method, and is sleeved between the nut 12 and the bearing sleeves 13a and 13b, and the ball retainer 14 is provided with a plurality of annular thin-walled bodies. The holding portion 141. The plurality of second balls 16a are accommodated in the holding portion 141, and the circumference of each of the holding portions 141 is not less than one-half of the circumference of the largest section of each of the second balls 16a accommodated therein.

In the present embodiment, as shown in FIG. 1D, each of the holding portions 141 is exemplified as a closed-type hoist hole holder. Since the ball retainer 14 has the retaining portion 141 of the gourd-shaped arc-shaped sleeve hole configuration, the second ball 16a can be fitted into the inserting combination, so that the ball retainer is provided by the retaining portion 141 of the large cladding angle configuration. Each of the second balls 16a is stably fixed in position. Moreover, since the retaining portion 141 of the gourd-shaped circular arc-shaped through-hole configuration has a local deformability, the second ball 16a can be easily fitted into the retaining portion 141 of the ball retainer 14.

The laminated manufacturing method adopted by the ball retainer 14 can be one of the following methods: Selective laser sintering (SLS), Stereolithography apparatus (SLA), and inkjet printing (Ink) Jet printing, IJP), or Fused deposition modeling (FDM). The material of the ball cage 14 can be nylon (Nylon), acrylonitrile-butadiene-styrene copolymer (ABS), carbon fiber reinforced plastic, carbon nanotube reinforced plastic, glass fiber reinforced plastic, polyfluorinated divinyl (PVDF), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), or polyimide (PI), or any combination of the above.

Further, in order to improve the wear resistance and lubricity of the ball retainer 14 to increase its service life, a composite material may be used, that is, ceramic powder (for example, zirconia powder, oxidation) is further added when the ball cage 14 is manufactured. Aluminum powder, cerium oxide powder, aluminum nitride powder, tantalum nitride powder, tantalum carbide powder, carbon nanotubes) or lubricous materials such as graphite powder, carbon powder, and solid lubricant. Further, in order to strengthen the structural strength of the ball retainer 14, glass fibers, carbon fibers, strontium carbide fibers, or whisker fibers may be added.

1C is a schematic cross-sectional view of the ball screw device shown in FIG. 1A, which is also referred to FIG. 1A to FIG. 1C. The bearing sleeves 13a and 13b are respectively sleeved on both sides of the nut 12, and the nut 12 has a plurality of outer ball grooves 121. In the embodiment, the nut 12 has two outer ball grooves 121, and the bearing sleeve 13a And 13b respectively have a second inner ball groove 131a, 131b, and The configuration of the surrounding mode, the guiding pitch and the groove corresponds to the outer ball groove 121, so that when the bearing sleeves 13a, 13b are sleeved on the nut 12, the second inner ball grooves 131a, 131b can be combined with the outer ball groove The groove 121 forms a second ball passage for accommodating the plurality of second balls 16a to rotate the nut 12 relative to the bearing sleeves 13a, 13b. The outer ball groove 121 is formed perpendicular to the axial direction of the screw 11. Of course, in other embodiments, the outer ball groove 121 may be inclined with respect to the axial direction of the screw 11 to have an angle. The present invention is not limited thereto.

In addition, as shown in FIG. 1C, as described above, the second ball passage is a main portion of the ball circulation passage between the screw 11 and the nut 12, and accommodates a plurality of second balls 16a (FIG. 1B and FIG. 1C only show Part of the ball is representative, so that the nut 12 can be rotated about the axis of the screw 11 to convert the rotary motion into a linear motion. It should be noted that the ball reflow method of the present invention is not limited to the outer circulation type, the inner circulation type or the end cover circulation type. In the embodiment, only the end cover circulation type is taken as an example, but For the detailed description, please refer to the following. The arrangement of the screw and the nut and the formation of the groove are understood by those of ordinary skill in the art, and will not be described again.

1E is a schematic exploded perspective view of the ball screw device shown in FIG. 1A. As shown, the holding portion 141 has a concave conical surface in a radial section and an outer contour surface of the second ball 16a. Cooperating with each other, the second ball 16a is further positioned while being rolled.

Please refer to Figure 1C. The two bearing sleeves 13a, 13b each have an inner positioning groove 132a, 132b, and the ball screw device 1 further has an annular positioning member 19. Wherein, the annular positioning element 19 is sandwiched between the two bearing sleeves 13a, 13b, and the annular positioning element 19 is received in the inner positioning grooves 132a, 132b. Preferably, the outer surface of the annular positioning member 19 abuts against the sidewall of the inner positioning groove 132a, 132b, and the annular positioning member 19 is received in the inner positioning groove 132a, 132b concentrically with the two bearing sleeves 13a, 13b. Thereby, the bearing sleeve 13a and the bearing sleeve 13b are thereby positioned relative to each other, and because of the annular positioning member 19, the tolerance of the alignment between the bearing sleeves 13a, 13b can be further significantly reduced. Since the relative position between the annular positioning element 19 and the bearing sleeves 13a, 13b is preferably in a concentric relationship, the annular positioning element 19 may also be referred to as a concentric ring.

In addition, the preload adjusting member 15 is also interposed between the two bearing sleeves 13a, 13b, and the inner diameter of the preload adjusting member 15 is larger than the outer diameter of the annular positioning member 19, as shown in FIG. 1C, the annular positioning member 19 and the pre The pressure adjusting elements 15 are all clamped to the two bearing sleeves 13a, 13b, and are pre-stressed The integral element 15 is disposed on the outer periphery of the annular positioning element 19, but the pre-stressing adjustment element 15 is not in contact with the annular positioning element 19.

Preferably, the components are fixed to each other in a screw-lock manner. Therefore, the bearing sleeves 13a and 13b and the pre-stressing adjusting component 15 respectively have a plurality of screw holes S1, and the positions of the screw holes S1 correspond to each other and are screwed. S2 locks the bearing sleeves 13a, 13b and the preload adjusting element 15 to each other. The preload adjusting member 15 is preferably made of rigid iron to provide better rigidity and toughness, to facilitate control of the pressure between the bearing sleeves 13a, 13b during the manufacturing process, and to increase the overall operational stability of the ball screw device 1. The bearing sleeve assembly B is formed by assembling the two bearing sleeves 13a, 13b, the annular positioning member 19, the ball retainer 14, the second ball 16a, and the preload adjusting member 15.

In addition, the present invention further provides a bearing sleeve assembly of a ball screw device, which is sleeved on a nut. The bearing sleeve assembly includes two bearing sleeves, an annular positioning component, a ball retainer, a plurality of balls, and a preload adjusting component. The two bearing sleeves respectively have an inner positioning groove and an inner ball groove, and the inner ball groove is correspondingly arranged with the plurality of outer ball grooves of the nut, so that each inner ball groove and each outer ball groove form a ball channel . The annular positioning element is sandwiched between the two bearing sleeves, and the annular positioning element is received in the inner positioning groove. The ball retainer has an annular thin-walled body and is formed by a laminated manufacturing method and is sleeved between the nut and the two bearing sleeves, and a plurality of retaining portions are disposed on the annular thin-walled body. The plurality of balls are housed in the holding portion and the ball passage, and the circumference of each of the holding portions is not less than one-half of the circumference of the largest section of each of the balls housed therein. The preload adjusting component is sandwiched between the two bearing sleeves. For specific component structures and features, reference may be made to the previous embodiment, and details are not described herein.

In addition, the present invention further provides another ball screw device, please refer to FIG. 2A to FIG. 2F. 2A is a schematic view of a ball screw device according to an embodiment of the present invention, FIG. 2B is an exploded perspective view of the ball screw device shown in FIG. 2A, and FIG. 2C is a cross-sectional view of the ball screw device shown in FIG. 2A taken along a section line AA. 2D is a schematic view of the ball retainer in the ball screw device shown in FIG. 2A, and FIGS. 2E and 2F are schematic views of another ball retainer in the ball screw device shown in FIG. 2A.

First, please refer to FIG. 2A to FIG. 2C together. In this embodiment, the ball screw device 2 includes a screw 21, a nut 22, a bearing sleeve 23, a plurality of first balls 26b, and at least one ball retainer. 24, a plurality of second balls 26a, a plurality of reflow elements 27, a plurality of dust-proof groups A member 28 and at least one reinforcement member 29.

The inner side surface of the nut 22 has a plurality of first inner ball grooves 222, and the outer surface of the screw 21 has a plurality of spiral grooves 211. In the present embodiment, the first inner ball groove 222 and the spiral groove 211 are spiral grooves. When the nut 22 is sleeved on the screw 21, the first inner ball groove 222 will form a first ball passage P1 together with the corresponding spiral groove 211. The first ball 26b is accommodated in the first ball passage P1. Specifically, in order to make the drawing simple and convenient for understanding, FIG. 2C only shows a part of the second ball 26a and a part of the first ball 26b. In the present embodiment, the ball screw device 2 further includes two reflow elements 27 which can be sleeved on both ends of the nut 22, and each reflow element 27 has two return passages 271. Next, referring to FIG. 2C together, when the first ball 26b rolls into the reflow element 27 in the first ball passage P1, the first ball 26b can be reflowed from the return passage 271 to enter and correspond to the return passage 271 and The circulation passage 213 of the nut 22 is axially penetrated. Therefore, the first ball passage P1 (ie, the first inner ball groove 222 and the spiral groove 211), the return passage 271, and the circulation passage 213 form a complete ball circulation path RP. When the first ball 26b moves to the position of the reflow element 27 in the first ball passage P1, a reverse circulation motion is generated by the return passage 271 and the circulation passage 213. In the present embodiment, the number of the circulation passages 213 is preferably the number corresponding to the return passages 271. The ball screw device 2 of the present embodiment further includes four reinforcing members 29, which may be made of metal, which are respectively disposed on the return passage 271 of the reflow element 27, so that when the first ball 26b is reflowed via the reflow element 27, the first The balls 26b roll on the reinforcing member 29 instead of rolling directly on the reflow member 27 to reduce the wear of the return passage 271.

The nut 22 has at least one outer ball groove 221 . However, those having ordinary knowledge in the art can understand that an outer ball groove 221 can be disposed on the nut 22, and can also increase the stability of the rotation of the bearing sleeve 23 and/or the bearing capacity of the ball screw device 2, and A plurality of outer ball grooves 221 are provided on the cap 22. This embodiment is described by taking the nut 22 having two outer ball grooves 221 as an example. Two outer ball grooves 221 are provided on the outer side surface OS of the nut 22. The bearing sleeve 23 has at least one second inner ball groove 231 disposed on the inner side surface IS of the bearing sleeve 23. For the same reason as described in the preceding paragraph, it is clear to those skilled in the art that the bearing sleeve 23 can correspond to the outer ball groove 221 on the nut 22, and a second inner ball groove 231 can be provided. The stability of the rotation of the bearing sleeve 23 and/or the bearing capacity of the ball screw device 2, A plurality of second inner ball grooves 231 are disposed on the bearing sleeve 23. In this embodiment, the bearing sleeve 23 has two second inner ball grooves 231 as an example. When the bearing sleeve 23 is sleeved on the nut 22, the second inner ball groove 231 of the bearing sleeve 23 and the corresponding outer ball groove 221 together form a second ball passage P2, as shown in FIG. 2C.

Referring to FIG. 2B again, the ball retainer 24 has a plurality of retaining portions 241 which are preferably shaped to conform to the arc shape of the second ball 26a and have an arc length not less than a half of the circumference of the largest cross section of the second ball 26a. One. When the second ball 26a is placed in the second ball passage P2, the ball retainer 24 can also be sleeved on the nut 22 and located between the bearing sleeve 23 and the nut 22, and corresponding to the second ball 26a by the holding portion 241. The engagement is performed to maintain and fix the position of each of the second balls 26a, thereby preventing the second ball 26a from falling off during the actual operation of the ball screw device 2.

In this embodiment, each of the retaining portions 241 is a C-shaped recess, and the angle of each of the C-shaped recesses covering each of the second balls 26a is preferably greater than 180 degrees. More preferably, refer to FIG. 2D, which is 200. The second ball 26a is positioned to operate at a degree of 270 degrees. The wall thickness of the ball retainer 24 shown in Fig. 2D can be increased by 20-50% compared to the thickness of the ball retainer 24 shown in Fig. 2C, making it more wear resistant and increasing the service life.

In addition, in another embodiment, each C-shaped recess of the ball retainer 24 has a crowned top portion 2411 and a bottom portion 2412. As can be seen, the radial thickness of the crowned top portion 2411 is greater than the radial thickness of the bottom portion of 2412. In this embodiment, the crown top is increased in thickness, which improves the coating area and structural strength of the first ball 26b and increases the stability during operation. In addition, the C-shaped recess can also have a larger cladding angle (200-270 degrees) to cover the first ball 26b, so that the second ball 26a can be positioned more smoothly.

The laminated manufacturing method adopted by the ball retainer 24 may be one of the following methods: Selective laser sintering (SLS), Stereolithography apparatus (SLA), and inkjet printing (Ink) Jet printing, IJP), or Fused deposition modeling (FDM). The material of the ball cage 14 can be nylon (Nylon), acrylonitrile-butadiene-styrene copolymer (ABS), carbon fiber reinforced plastic, carbon nanotube reinforced plastic, glass fiber reinforced plastic, polyfluorinated divinyl (PVDF), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), or polyimide (PI), or any combination of the above.

Further, in order to improve the wear resistance and lubricity of the ball retainer 24 to increase its service life, a composite material may be used, that is, a ceramic powder (for example, zirconia powder, alumina) may be further added to the ball retainer 24 for manufacture. Powder, cerium oxide powder, aluminum nitride powder, tantalum nitride powder, tantalum carbide powder, carbon nanotubes) or lubricating materials such as graphite powder, carbon powder, and solid lubricant. Further, in order to strengthen the structural strength of the ball retainer 24, glass fiber, carbon fiber, strontium carbide fiber, or whisker fiber may be added.

The ball cage 24 is made of a material such as nylon, and the selective laser sintering (SLS) process in the laminated manufacturing method has a certain self-lubricity and selective laser sintering. The technology uses laser light to form the nylon powder, so that the inside of the finished product will contain tiny holes and the surface will be slightly concave. Both of them have the function of oil storage, so the ball retainer 24 of this design structure will have good Lubricity reduces friction caused by rotation and improves bearing life. The toughness and lubricity of the nylon material enable the second ball 26a to operate smoothly in the second ball passage P2 and the holding portion 241. In addition, since the holding portion 241 of the ball retainer 24 of the present embodiment has a small contact hole with respect to the second ball 26a due to the non-closed hole, the friction is also small, and the ball retainer 24 has a simple structure. It is light in weight and easy to manufacture and manufacture.

Compared with the injection molding method, since the ball retainer 24 has an annular thin-walled body, regardless of whether the mold is ejected by a single point or a multi-point nozzle, a bonding wire is generated after cooling, resulting in stress concentration, shape deformation or Shortcomings such as reduced strength and reduced service life. This embodiment is manufactured by the laminated manufacturing method, so that it is not necessary to make a complicated injection mold, which can save the mold cost and reduce the cost. In addition, compared with the traditional ball cages made of CNC milling machines and wire-cut electrical discharge machining, the traditional CNC milling machines and wire-cut electrical discharge machining manufacturing processes are complicated, and the metal ball cages have poor corrosion resistance. Higher manufacturing costs.

In the present embodiment, the ball screw device 2 further includes two dustproof components 28 that can be sleeved on both ends of the nut 22 and located outside the return element 27. The dustproof component 28 includes a dustproof member 281 and a fixing member 282, and the dustproof member 281 has a wiping portion 2811. After the assembly is completed, the wiping portion 2811 contacts the outer surface of the screw 21 to block moisture, dust or foreign matter from entering the ball screw device. The inside of the 2 makes it work properly and even extends the life of the entire unit. The fixing member 282 is fastened to both ends of the nut 22 and disposed on the outer side of the dustproof member 281 to prevent The dust member 281 is not easy to fall when the ball screw device 2 performs a linear motion. The number of the above components (the reflow element 27, the return passage 271, the dustproof assembly 28, and the reinforcing member 29) is merely an example, and the present invention is not limited to the above, and can be adjusted according to practical applications.

As described above, the ball screw device and the bearing sleeve assembly of the present invention are manufactured by a laminated manufacturing method because the ball retainer has an annular thin-walled body, compared with the conventional CNC milling machine and wire-cut electrical discharge machining. The processing method has a high yield. At the same time, the circumference of the plurality of retaining portions provided on the annular thin-walled body is not less than one-half of the circumferential length of the largest section of each of the balls accommodated therein, and has a tilting mode configuration. When machining with conventional tools or injection molding, special tools or additional design of radially moving sliders are required, which is expensive. However, the present invention is produced by a laminate manufacturing (3D printing) method, and the ball holder having the inverted mold inclination configuration can be directly produced, so that the cost is low.

In addition, since the ball retainer of the present invention can be made of a plastic resin material, it has the advantages of light weight, low noise, good lubricity and the like.

The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims.

1‧‧‧Ball screw device

11‧‧‧ screw

111‧‧‧Spiral groove

12‧‧‧ Nuts

121‧‧‧Outer ball groove

123‧‧‧First inner ball groove

13a, 13b‧‧‧ bearing sleeve

14‧‧‧Ball retainer

141‧‧‧ Holding Department

15‧‧‧Preloading adjustment components

16a‧‧‧second ball

16b‧‧‧First Ball

17‧‧‧Dust-proof parts

18‧‧‧End cover

19‧‧‧Ring positioning elements

P‧‧‧Drive connector

Claims (17)

A bearing sleeve assembly of a ball screw device is sleeved on a nut, comprising: two bearing sleeves respectively having an inner positioning groove and an inner ball groove, the inner ball groove and a plurality of outer balls of the nut Correspondingly disposed, the inner ball groove and each of the outer ball grooves form a ball passage; an annular positioning member is sandwiched between the two bearing sleeves, and the annular positioning component is disposed therein a positioning groove; at least one ball retainer having an annular thin-walled body and formed by lamination manufacturing and sleeved between the nut and the bearing sleeves, and the annular thin wall a plurality of retaining portions are disposed on the body; a plurality of balls are received in the retaining portions and the ball passages, and a circumference of each of the retaining portions is not less than one-half of a circumference of a maximum cross-section of each of the balls accommodated therein And a pre-stressing adjustment element is sandwiched between the two bearing sleeves. The bearing sleeve assembly of claim 1, wherein each of the retaining portions has a concave conical surface in a radial section. The bearing sleeve assembly of claim 1, wherein each of the retaining portions has a C-shaped recess, and each of the C-shaped recesses covers the respective balls at an angle greater than 180 degrees. The bearing sleeve assembly of claim 3, wherein each C-shaped notch covers each of the balls at an angle of 200 to 270 degrees. The bearing sleeve assembly of claim 4, wherein each of the C-shaped recesses has a crowned top and a bottom, the radial thickness of the crowned top being greater than the radial thickness of the bottom. The bearing sleeve assembly of claim 1, wherein the laminated manufacturing method is selected from the group consisting of: selective laser sintering (SLS), photocuring ( Stereolithography apparatus (SLA), Ink jet printing (IJP), and Fused deposition modeling (FDM). The bearing sleeve assembly of claim 1, wherein the material of the ball cage is selected from the group consisting of nylon (Nylon), acrylonitrile-butadiene-styrene copolymer (ABS), carbon fiber reinforced plastic, and nanometer. Carbon tube reinforced plastic, glass fiber reinforced plastic, polyfluorinated diethylene (PVDF), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), And a group of polyimides (PI). The bearing sleeve assembly of claim 7, wherein the ball retainer is further provided with zirconia powder, alumina powder, cerium oxide powder, aluminum nitride powder, tantalum nitride powder, tantalum carbide powder, nanometer. Carbon tube, carbon powder, glass fiber, carbon fiber, tantalum carbide fiber, or whisker fiber. A ball screw device includes: a screw; a nut sleeved on the screw, and a first ball passage between the nut and the screw, the outer surface of the nut has a plurality of outer ball grooves; a first ball is received in the first ball passage; and a bearing sleeve assembly includes: two bearing sleeves respectively having an inner positioning groove and an inner ball groove, the inner ball groove and the nut The outer ball grooves are correspondingly disposed such that each inner ball groove and each outer ball groove form a second ball passage; an annular positioning member is sandwiched between the two bearing sleeves, and the annular positioning component is The ball retainer is disposed in the inner positioning groove; at least one ball retainer having an annular thin-wall body and being formed by lamination and sleeved between the nut and the bearing sleeves, and The annular thin-walled body is provided with a plurality of retaining portions; a plurality of second balls are received in the retaining portions and the second ball passages, and the circumference of each of the retaining portions is not less than each of the second balls received therein The maximum length of the circumference of the largest section And a preload adjusting member interposed between the two bearing sleeves. The ball screw device of claim 9, wherein each of the retaining portions has a concave conical surface in a radial section. A ball screw device includes: a screw; a nut sleeved on the screw, and a first ball passage between the nut and the screw, the outer surface of the nut has a plurality of outer ball grooves; a first ball is received in the first ball passages; a bearing sleeve is sleeved on the nut, the inner surface of the bearing sleeve is provided with at least one inner ball groove, and the inner ball groove and the corresponding outer ball groove form a second ball passage; at least one ball retainer The ball cage has an annular thin-walled body and is formed by laminating and sleeved on the nut, and a plurality of retaining portions are disposed on the annular thin-walled body; the plurality of second balls are accommodated The holding portion and the second ball passage, and the circumference of each of the holding portions is not less than one-half of a circumference of a maximum cross section of each of the second balls housed therein. The ball screw device of claim 11, wherein each of the retaining portions has a C-shaped recess, and each of the C-shaped recesses covers each of the second balls at an angle greater than 180 degrees. The ball screw device of claim 12, wherein each C-shaped notch covers each of the second balls at an angle of 200 to 270 degrees. The ball screw device of claim 13, wherein each of the C-shaped recesses has a crowned top and a bottom, the radial thickness of the crowned top being greater than the radial thickness of the bottom. The ball screw device according to claim 9 or 11, wherein the laminated manufacturing method is one selected from the group consisting of: selective laser sintering (SLS), photocuring Stereolithography apparatus (SLA), Ink jet printing (IJP), and Fused deposition modeling (FDM). The ball screw device according to claim 9 or 11, wherein the material of the ball cage is selected from the group consisting of nylon (Nylon), acrylonitrile-butadiene-styrene copolymer (ABS), carbon fiber reinforced plastic, Nano carbon tube reinforced plastic, glass fiber reinforced plastic, polyfluorinated diethylene (PVDF), polytetrafluoroethylene (PTFE), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), and polyimide A group of (PI) groups. The ball screw device according to claim 16, wherein the ball retainer is further provided with zirconia powder, alumina powder, cerium oxide powder, aluminum nitride powder, tantalum nitride powder, tantalum carbide powder, and nanometer. Carbon tube, carbon powder, glass fiber, carbon fiber, tantalum carbide fiber, or whisker fiber.