CN111365432B

CN111365432B - Cooling type ball screw device capable of being used for multi-tooth mouth circulation

Info

Publication number: CN111365432B
Application number: CN201811586363.2A
Authority: CN
Inventors: 庄裕纬; 甘嘉伦
Original assignee: Hiwin Technologies Corp
Current assignee: Hiwin Technologies Corp
Priority date: 2018-12-25
Filing date: 2018-12-25
Publication date: 2021-09-21
Anticipated expiration: 2038-12-25
Also published as: CN111365432A

Abstract

A cooling type ball screw device for multi-tooth mouth circulation comprises a screw, a nut unit and at least one cooling bridging unit. The screw rod is provided with a plurality of external thread guiding parts, the nut unit is arranged on the screw rod in a threaded mode through a plurality of ball groups and comprises two end parts, a plurality of backflow channel groups and a cooling channel group, each backflow channel group is provided with an internal thread guiding part, an axial through hole and two circulating end parts, one of the axial through holes is arranged between two cooling channels arranged at intervals around the axis of the cooling channel group, the cooling bridging unit comprises a bridging part, the bridging part is provided with a bridging main body and two connecting pipes connected with the bridging main body, and the bridging main body corresponds to one of the circulating end parts and spans between the two cooling channels. The cooling bridging unit is suitable for a multi-tooth-opening ball screw and can achieve the cooling purpose.

Description

Cooling type ball screw device capable of being used for multi-tooth mouth circulation

Technical Field

The present invention relates to a cooling ball screw, and more particularly to a cooling ball screw device for multi-port circulation.

Background

There is a ball screw with double thread openings (taiwan certificate number M467770), which has two independent ball circulation channels for two ball sets to circulate, each of the ball circulation channels includes a track groove disposed on the outer surface of the screw, an inner ball groove disposed on the inner circumferential surface of a nut body, a return channel disposed between the inner circumferential surface and the outer circumferential surface of the nut body, and two end circulation end pieces disposed on two sides of the nut body, wherein each of the end circulation end pieces has a return bend communicating with the return channel and the inner ball groove. The double-tooth-opening ball screw has no cooling flow channel, so that the ball screw is easy to generate thermal deformation of parts due to high temperature during operation, and the machining precision and the machining efficiency are influenced.

In order to cool the ball screw and improve the processing accuracy and efficiency, another conventional ball screw (taiwan certificate No. I230232) has a nut with a plurality of cooling holes axially communicating between two ends, and end caps are disposed at two sides of the nut, respectively, and the end caps have a plurality of grooves for communicating two adjacent cooling holes.

Although the ball screw can cool the nut by cooling fluid flowing through the cooling through holes and the grooves, the ball screw is not suitable for a multi-threaded ball circulation structure, mainly because the multi-threaded ball circulation structure is provided with a plurality of return channel groups inside the nut, each return channel group is provided with an inner guide thread part spirally wound on an inner ring surface of the nut, an axial through hole arranged along the axial direction, and two circulation end pieces respectively corresponding to two opposite end parts of the nut and communicated with the axial through hole and the corresponding inner guide thread part. At least one axial through hole of the return channel group is crossed and communicated with the cooling flow channel. That is, circulation end pieces for circulating the balls are installed at both ends of the nut, and in order to install the circulation end pieces, it is necessary to form concave holes in the nut, and some of the concave holes may destroy the airtightness of the cooling through holes and the grooves.

There is still another ball screw (taiwan certificate number M532003), which is only suitable for single-thread mouth and has a cooling channel. Obviously, a cooling circulation structure of a multi-port ball screw is urgently developed.

Disclosure of Invention

The invention aims to provide a cooling type ball screw device which can avoid thermal deformation of parts and can be used for multi-tooth-mouth circulation.

The invention relates to a cooling type ball screw device capable of being used for multi-thread circulation, which comprises a screw rod, a screw cap unit and at least one cooling bridging unit, wherein the screw rod extends along an axis and is provided with an outer circumferential surface and a plurality of outer guide thread parts spirally wound on the outer circumferential surface, the screw cap unit is spirally arranged on the screw rod through a plurality of ball groups and comprises two end parts which are oppositely arranged along the axis, an inner ring surface which is communicated with the end parts and surrounds the axis and can define a shaft hole, a plurality of backflow channel groups which are arranged between the end parts corresponding to the outer guide thread parts and are wound on the cooling channel groups between the end parts, each backflow channel group is provided with an inner guide thread part spirally wound on the inner ring surface and opposite to the outer guide thread parts, and an axial through hole which extends corresponding to the axis and is arranged between the end parts, and two circulation end pieces which respectively correspond to the end parts and are communicated with the axial through holes and the corresponding inner thread guiding parts, each backflow channel group and each outer thread guiding part jointly define a ball circulation channel for each ball group to circularly operate, each cooling channel group is provided with a plurality of cooling flow channels which are arranged at intervals around the axis and a plurality of communication parts which approach to the end parts and are communicated with the cooling flow channels, the axial through hole of each backflow channel group is arranged between the two cooling flow channels which are adjacently arranged around the axis, the cooling bridging unit is arranged at one end part of the nut unit and comprises a bridging piece, the bridging piece is provided with a bridging main body and two connecting pipes which are connected with the bridging main body, the bridging main body corresponds to one circulation end piece and spans between the two cooling flow channels which are arranged at two sides of the circulation end piece around the axis, the bridging main body is hollow and defines a flow guide channel communicated with the cooling channel group together with the connecting pipe.

The cooling bridging unit further comprises a cover member assembled to the bridging member, the bridging body has an outer side surface, an inner side surface opposite to the outer side surface corresponding to the axis, and a guide groove recessed from the outer side surface to the inner side surface, the inner side surface is opposite to the circulation end member, the connecting pipe is connected to the inner side surface, and the cover member is airtight and positioned on the outer side surface and closes the guide groove.

The cooling type ball screw device for multi-tooth mouth circulation of the invention further comprises a leakage-proof piece arranged between the bridging piece and the sealing cover piece.

The cooling type ball screw device applicable to multi-tooth mouth circulation comprises a nut unit, a cooling bridging unit and a cover piece, wherein one end of the nut unit is provided with an end face, a sunken part is concavely arranged on the end face, the cooling bridging unit is arranged in the sunken part, and the cover piece corresponds to the end face.

The cooling type ball screw device capable of being used for multi-tooth mouth circulation is characterized in that one end part of the nut unit is also provided with a plurality of lock holes drilled from the end surface and arranged on the periphery of the sunken part, the cover piece of the cooling bridging unit is provided with a main plate part capable of sealing the guide grooves and a plurality of lug parts connected to the main plate part, each lug part is provided with a through hole corresponding to the lock hole, and the cooling bridging unit is also provided with a plurality of screws which are arranged in the through holes in a threaded mode and are locked in the lock holes in a threaded mode.

The cooling type ball screw device for multi-tooth mouth circulation further comprises two sealing rings arranged between the connecting pipe and the cooling channel group.

The invention has the beneficial effects that: the cooling bridging unit is arranged between the two cooling flow passages in a spanning mode, so that the cooling bridging unit is suitable for a multi-tooth-opening ball screw, the nut body can generate a better cooling effect, and the processing precision and the processing efficiency can be improved.

Drawings

FIG. 1 is a perspective assembly view of one embodiment of a cooled ball screw apparatus useful in a multiple-mouthpiece cycle of the present invention;

FIG. 2 is a perspective assembly view of another perspective of the embodiment;

FIG. 3 is an exploded perspective view of the embodiment;

FIG. 4 is a fragmentary exploded perspective view of FIG. 3;

FIG. 5 is a side view of the embodiment;

FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5;

fig. 7 is a schematic plan-view development of the embodiment, illustrating a configuration of one cooling passage group and two return passage groups.

Detailed Description

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

Referring to fig. 1 to 4, an embodiment of a cooled ball screw device for multi-thread circulation according to the present invention includes a screw 10, a nut unit 20, and a cooling bridge unit 30. The embodiment of the present invention is described with a ball screw device having two screw ports, but may be a three-screw port or a four-screw port (not shown).

The screw 10 extends along an axis L and has an outer circumferential surface 11 and two outer lead screw portions 12 spirally wound around the outer circumferential surface 11.

The nut unit 20 is screwed to the screw 10 through two ball sets 40, and includes a nut body 21, two return channel sets 22 corresponding to the outer thread 12 and disposed on the nut body 21, and a cooling channel set 23 disposed on the nut body 21.

The nut body 21 has two opposite end portions 211, 211 ' along the axis L, an inner annular surface 213 communicating with the end portions 211, 211 ' and surrounding the axis L and defining a shaft hole 212, each of the end portions 211, 211 ' has an end surface 214, 214 ', a plurality of concave grooves 215, 215 ' recessed from the end surfaces 214, 214 ' and forming a meniscus, two support holes 216 recessed from the end surfaces 214, 214 ' and communicating with the inner annular surface 213, wherein one end surface 214 is further connected with an inlet pipe 217 and an outlet pipe 217 ', the other end surface 214 ' further has a recessed portion 218 recessed from the end surface 214 ' and communicating with one of the support holes 216, and two lock holes 219 drilled from the end surface 214 ' and disposed at the periphery of the recessed portion 218.

Each of the backflow channel sets 22 has an inner thread portion 221 spirally wound around the inner annular surface 213 and opposite to the outer thread portion 12, an axial through hole 222 extending corresponding to the axis L and disposed between the end portions 211 and 211 ', and two circulation end members 223 respectively corresponding to the end portions 211 and 211' and connected to the axial through hole 222 and the corresponding inner thread portion 221, the circulation end members 223 are respectively installed in the bearing holes 216, each backflow channel set 22 and each outer thread portion 12 together define a ball circulation channel for circulating each ball set 40, and the axial through holes 222 of the backflow channel set 22 are spaced 180 degrees around the axis L. In the case of a three-pronged ball screw device, the axial through-holes of the return channel set are spaced 120 degrees (not shown) about the axis L, and in the case of a four-pronged ball screw device, the axial through-holes of the return channel set are spaced 90 degrees (not shown) about the axis L. The circulation end pieces 223 are respectively installed in the receiving holes 216 of the nut body 21.

Referring to fig. 7, the cooling channel assembly 23 has a plurality of cooling channels 231 spaced around the axis L, and a plurality of end plugs 232 corresponding to the ends 211 and 211 ', respectively, wherein one of the cooling channels 231 is connected to the inlet pipe 217 and can introduce the cooling fluid, and the other cooling channel 231, which is located at one side of the cooling channel 231 around the axis L and spaced from the cooling channel 231 by an angle of about 270 degrees, is connected to the outlet pipe 217' and can discharge the heat-absorbed fluid. The end plugs 232 are respectively installed in the grooves 215 and 215', and each of the end plugs 232 has a communicating portion 233 communicating between two cooling channels 231 adjacently arranged around the axis L and having a concave hole shape. The axial through hole 222 of each return channel group 22 is interposed between two cooling channels 231 adjacently disposed around the axis L.

As shown in fig. 5 and 6, the cooling bridge unit 30 is installed at one end 211' of the nut unit 20 and installed in the recessed portion 218, corresponds to one of the circulating end pieces 223 and spans between two cooling channels 231 disposed at both sides of the circulating end piece 223 around the axis L, and has a bridge member 31, a cover member 32 assembled to the bridge member 31, a leakage preventing member 33 installed between the bridge member 31 and the cover member 32, two sealing rings 34 hermetically installed between the bridge member 31 and the corresponding cooling channels 231, and a plurality of screws 35.

The bridging member 31 has a bridging body 311, two connecting pipes 312 connected to the bridging body 311, the bridging body 311 is hollow, and defines a flow guiding channel 313 communicating with the cooling channel group 23 together with the connecting pipes 312.

The bridging body 311 has an outer side 314 corresponding to the end face 214', an inner side 315 opposite to the outer side 314 corresponding to the axis L, and a guide groove 316 recessed from the outer side 314 toward the inner side 315, the inner side 315 being opposite to one of the circulating end pieces 223, and the connecting tube 312 being connected to the inner side 315.

The cover 32 is hermetically positioned on the outer side 314 and corresponding to the end surface 214', the cover 32 has a main plate 321 for closing the guiding groove 316, and a plurality of ears 322 connected to the main plate 321, each of the ears 322 has a through hole 323 corresponding to the locking hole 219.

The leakage preventing member 33 is installed between the outer side surface 314 of the bridge member 31 and the main plate portion 321 of the cover member 32, and can make the guide groove 316 airtight.

The sealing ring 34 can be air-tightly installed between the connection pipe 312 and the corresponding cooling flow passage 231.

The screw 35 is inserted through the through hole 323 and screwed into the locking hole 219, so that the cooling bridge unit 30 can be detached and fixed to one of the ends 211' of the nut unit 20.

For a further understanding of the invention, its role, the technical means employed, and the efficacy attained by its cooperation, it is believed that the invention will be more fully and specifically understood from the following description.

As shown in fig. 1 and 2, after the assembly of the cooling ball screw device for multi-thread circulation is completed, the nut unit 20 is sleeved outside the screw 10, and the return channel 22 is used for circulating the ball set 40, so that the nut unit 20 can generate smooth linear displacement along the screw 10.

As shown in fig. 6 and 7, by the cooperation between the cooling channel group 23 of the nut unit 20 and the cooling bridging unit 30, and as shown by the dotted arrows in fig. 7, when the cooling fluid is introduced into the cooling channel group 23 from the inlet pipe 217, the cooling fluid can flow through the various parts of the nut body 21 by the smooth flow guidance of the cooling flow channel 231 and the communicating part 233 of the end plug 232, so that the cooling fluid can be cooled by the nut body 21, and finally the fluid after absorbing heat can be discharged from the outlet pipe 217'.

As shown in fig. 5, 6 and 7, the cooling bridging unit 30 is corresponding to one of the circulating end parts 223 and straddles between the two cooling channels 231 disposed on both sides of the circulating end part 223 around the axis L, so that the cooling channel group 23 and the return channel group 22 will not intersect or interfere with each other, and therefore the airtightness of the cooling channel group 23 will not be damaged, and the smooth operation of the return channel group 22 and the ball group 40 will not be affected.

Furthermore, the present invention utilizes the arrangement of the cooling bridging unit 30 to enable the multi-threaded ball screw device to generate a better cooling effect, thereby improving the processing precision and the processing efficiency and solving the problem of insufficient cooling of the multi-threaded ball screw for a long time.

It should be noted that the cooling bridge unit 30 of the present invention is a multi-piece design, and is mainly assembled by the bridge member 31 and the cover member 32, and in fact, the cooling bridge unit 30 can also be made as a single piece (not shown), and can achieve the intended purpose and function.

In summary, the present invention can be used for a cooling type ball screw device with multiple-thread circulation, has a simple overall structure and is easy to manufacture and assemble, and can solve the cooling problem of the existing multiple-thread ball screw, thereby achieving the object of the present invention.

Claims

1. The utility model provides a can be used to many mouthfuls of circulating cooled ball screw device, contains screw rod, nut unit and at least one cooling bridging unit, its characterized in that:

the screw rod extends along the axis and is provided with an outer peripheral surface and a plurality of outer guide thread parts spirally wound on the outer peripheral surface;

the nut unit is screwed on the screw rod through a plurality of ball groups and comprises two end parts which are oppositely arranged along the axis, an inner ring surface which is communicated with the end parts and surrounds the axis and can define a shaft hole, a plurality of backflow channel groups which are arranged between the end parts corresponding to the outer thread guiding parts, and a cooling channel group which is wound between the end parts, the backflow channel groups are respectively provided with an inner thread guiding part which is spirally wound on the inner ring surface and is opposite to the outer thread guiding parts, an axial through hole which extends corresponding to the axis and is arranged between the end parts, and two circulating end parts which respectively correspond to the end parts and are communicated with the axial through hole and the corresponding inner thread guiding part, and each backflow channel group and each outer thread guiding part define a ball circulating channel for each ball group to circularly operate together, the cooling channel group is provided with a plurality of cooling channels which are arranged around the axis at intervals and a plurality of communication parts which approach to the end part and are communicated with the cooling channels, and the axial through hole of each backflow channel group is arranged between two adjacent cooling channels which are arranged around the axis;

the cooling bridging unit is arranged at one end of the nut unit and comprises a bridging piece and a sealing cover piece assembled on the bridging piece, the bridging piece is provided with a bridging main body and two connecting pipes connected with the bridging main body, the bridging main body corresponds to one circulating end piece and spans between two cooling flow channels arranged at two sides of the circulating end piece around the axis, the bridging main body is hollow and defines a flow guide channel mutually communicated with the cooling channel group together with the connecting pipes, the bridging main body is provided with an outer side surface, an inner side surface opposite to the outer side surface corresponding to the axis and a guide groove concavely arranged from the outer side surface to the inner side surface, the inner side surface is opposite to the circulating end piece, the connecting pipes are connected to the inner side surface, and the sealing cover piece is airtight and positioned at the outer side surface, and closes the channel.

2. The cooled ball screw apparatus usable with multi-mouthpiece circulation of claim 1, wherein: the cooling bridge unit further comprises a leakage preventing member installed between the bridge member and the cover member.

3. The cooled ball screw apparatus usable with multi-mouthpiece circulation of claim 1, wherein: one end of the nut unit is provided with an end face and a sunken part formed by the end face in a concave mode, the cooling bridging unit is installed in the sunken part, and the cover piece corresponds to the end face.

4. The cooled ball screw apparatus usable with multi-mouthpiece circulation of claim 3, wherein: one of them tip of nut unit still has the several by the terminal surface bores to establish and set up in the peripheral lockhole of heavy concave part, the closing cap spare of cooling bridging unit has and to seal the main board portion of guide slot to and the several connect in the ear of main board portion, the ear respectively have corresponding to the perforation of lockhole, cooling bridging unit still has several and wears to locate perforation and spiral shell lock locate the screw of lockhole.

5. The cooled ball screw device for multi-mouthpiece circulation according to any one of claims 1 to 4, wherein: the cooling bridging unit is also provided with two sealing rings which are arranged between the connecting pipe and the cooling channel group.