CN111609103A - Ball screw pair - Google Patents
Ball screw pair Download PDFInfo
- Publication number
- CN111609103A CN111609103A CN202010392458.1A CN202010392458A CN111609103A CN 111609103 A CN111609103 A CN 111609103A CN 202010392458 A CN202010392458 A CN 202010392458A CN 111609103 A CN111609103 A CN 111609103A
- Authority
- CN
- China
- Prior art keywords
- screw shaft
- peripheral surface
- sealing
- fixing ring
- ring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H25/00—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms
- F16H25/18—Gearings comprising primarily only cams, cam-followers and screw-and-nut mechanisms for conveying or interconverting oscillating or reciprocating motions
- F16H25/20—Screw mechanisms
- F16H25/24—Elements essential to such mechanisms, e.g. screws, nuts
- F16H25/2418—Screw seals, wipers, scrapers or the like
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Transmission Devices (AREA)
Abstract
The invention discloses a ball screw pair, which comprises a linear screw shaft and a cylindrical nut screwed with the screw shaft, wherein the outer peripheral surface of the screw shaft is a continuous smooth surface, the end parts of the two axial inner diameter sides of the nut are respectively provided with an annular concave cavity seat, an integral annular sealing assembly is arranged in the annular concave cavity seats, and the sealing part of the sealing assembly is always tightly attached to the outer peripheral surface of the screw shaft to realize sealing connection when the screw shaft rotates; the advantage is that the sealing assembly's that its adopted sealing component sealing part can scrape the grease on the peripheral face of screw shaft totally, has stopped appearing the phenomenon that grease scatters around under centrifugal force to the sealing assembly's that adopts sealing assembly's sealing part can seal the clearance between nut and the screw shaft well, has protected nut and screw shaft to avoid the invasion of dust etc. has prevented leaking of unnecessary grease in the nut more effectively.
Description
Technical Field
The invention relates to a transmission mechanism, in particular to a ball screw pair.
Background
The ball screw assembly is a transmission mechanism that converts rotational motion into linear motion. The ball screw assembly includes a linear screw shaft and a nut fitted to the screw shaft, a spiral first rolling groove is formed in an outer peripheral surface of the screw shaft, a spiral second rolling groove opposed to the first rolling groove is formed in an inner peripheral surface of the nut, the inner peripheral surface of the nut is screwed to the outer peripheral surface of the screw shaft via a plurality of balls interposed between the first rolling groove and the second rolling groove, and the nut can be moved in an axial direction of the screw shaft by rotating the screw shaft.
In order to prevent dust and the like from entering between the nut and the screw shaft from the outside and to prevent grease interposed between the nut and the screw shaft from leaking to the outside, a conventional ball screw assembly is generally provided with a sealing device at both axial end portions of the nut. In the conventional sealing device, a gap between an inner peripheral surface of a conventional seal and an outer peripheral surface of a screw shaft is uniform and small, and grease on the outer peripheral surface of the screw shaft is scraped to a certain thickness.
Disclosure of Invention
The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a ball screw assembly in which a sealing portion of a sealing member is used to scrape grease on an outer peripheral surface of a screw shaft, and a phenomenon that grease is scattered around under centrifugal force is prevented, and the sealing portion of the sealing member is used to seal a gap between a nut and the screw shaft, thereby protecting the nut and the screw shaft from dust and the like, and more effectively preventing leakage of excess grease in the nut.
The technical scheme adopted by the invention for solving the technical problems is as follows: a ball screw assembly comprising a linear screw shaft and a cylindrical nut screwed to the screw shaft, characterized in that: the outer peripheral face of the screw shaft is a continuous smooth face, the end parts of the two inner diameter sides of the axial direction of the nut are respectively provided with an annular concave cavity seat, a sealing assembly which is integrally annular is installed in the annular concave cavity seats, and when the screw shaft rotates, the sealing part of the sealing assembly is tightly attached to the outer peripheral face of the screw shaft all the time to realize sealing connection.
The outer peripheral surface of the screw shaft is provided with a spiral first rolling groove, the inner peripheral surface of the nut is provided with a spiral second rolling groove with the same lead as that of the first rolling groove, the first rolling groove and the second rolling groove are opposite to form a rolling channel, a plurality of balls are arranged in the rolling channel, and the nut is screwed with the screw shaft through the balls.
The sealing component comprises a first fixed ring, a sealing ring and a second fixed ring, the first fixed ring is matched with the annular cavity seat, the first fixing ring is provided with an annular groove, the sealing ring and the second fixing ring are just accommodated in the annular groove, the sealing ring is pressed between the groove bottom of the annular groove and the inner side shaft end surface of the second fixing ring, the outer shaft end surface of the second fixed ring is flush with the notch plane of the annular groove, the inner circumferential surface of the first fixed ring and the inner circumferential surface of the second fixed ring are in clearance fit with the outer circumferential surface of the screw shaft, the sealing ring is used as a sealing part of the sealing assembly, the inner peripheral surface of the screw shaft is in interference fit with the outer peripheral surface of the screw shaft, so that the inner peripheral surface of the sealing ring is always tightly attached to the outer peripheral surface of the screw shaft. The sealing ring is pressed between the first fixing ring and the second fixing ring, and the deformation of the sealing ring is prevented by using the fixing force of the first fixing ring and the second fixing ring; the seal assembly is mounted in an annular pocket with a generally first retainer ring on the inside and a second retainer ring on the outside.
On a plane perpendicular to the axial direction of the screw shaft, the inner peripheral surface contour line of the first fixing ring and the inner peripheral surface contour line of the second fixing ring are radially equidistant to the outer peripheral surface contour line of the screw shaft, the circumference of the inner peripheral surface contour line of the first fixing ring and the circumference of the inner peripheral surface contour line of the second fixing ring are both larger than the circumference of the outer peripheral surface contour line of the screw shaft by 0.6-0.8 mm, the inner peripheral surface contour line of the sealing ring is radially equidistant to the outer peripheral surface contour line of the screw shaft, and the circumference of the inner peripheral surface contour line of the sealing ring is smaller than the circumference of the outer peripheral surface contour line of the screw shaft by 1.6-1.8 mm.
The inner peripheral surface of the first fixed ring, the inner peripheral surface of the sealing ring and the inner peripheral surface of the second fixed ring are provided with spiral teeth with the inclination angle consistent with that of the first rolling groove.
A plurality of waist-shaped holes are uniformly formed in the sealing ring along the circumferential direction so as to meet the assembly requirement.
The interference between the inner circumferential surface of the seal ring and the outer circumferential surface of the screw shaft is 0.5 to 0.6mm, and the clearance between the inner circumferential surface of the first fixing ring and the inner circumferential surface of the second fixing ring and the outer circumferential surface of the screw shaft is 0.20 to 0.25 mm. The numerical value of the interference magnitude is larger than the numerical value of the gap magnitude, so that even if the sealing ring rotates along with the screw shaft and is filled in the gap between the first fixing ring, the second fixing ring and the screw shaft, the sealing ring can be well ensured to be tightly attached to the outer peripheral surface of the screw shaft.
The peripheral wall of the annular concave cavity seat is provided with a positioning hole. The positioning hole is provided to firmly confine the first retainer ring in the annular recess seat, and the seal assembly does not come off the end of the nut on the inner diameter side in the case of high-speed operation of the screw shaft.
The nut is provided with a lubricating grease injection hole and a lubricating grease overflow hole which are communicated with the inner hole of the nut.
Compared with the prior art, the invention has the advantages that:
because the outer peripheral surface of the screw shaft is a continuous smooth surface, the end parts of the two axial inner diameter sides of the nut are respectively provided with the sealing assembly, and the sealing part of the sealing assembly is always tightly attached to the outer peripheral surface of the screw shaft, the sealing part of the sealing assembly can scrape the lubricating grease on the outer peripheral surface of the screw shaft completely, thereby avoiding the residual redundant lubricating grease on the outer peripheral surface of the screw shaft and avoiding the phenomenon that the redundant lubricating grease scatters to the periphery under the centrifugal force under the condition of high-speed operation of the screw shaft; meanwhile, the sealing part of the sealing assembly can well seal the gap between the nut and the screw shaft, protect the nut and the screw shaft from dust and the like, and keep and seal the lubricating grease supplied to the interior of the nut, thereby more effectively preventing the leakage of the redundant lubricating grease in the nut.
Drawings
FIG. 1 is a schematic view of the overall structure of the ball screw assembly of the present invention;
FIG. 2 is a schematic sectional view taken along line A-A of FIG. 1;
FIG. 3 is a schematic view of the overall structure of the seal assembly in the ball screw assembly of the present invention;
FIG. 4 is an exploded view of the seal assembly of the ball screw assembly of the present invention;
FIG. 5 is a front view of the seal assembly in the ball screw assembly of the present invention;
fig. 6 is a schematic sectional view taken along line B-B of fig. 5.
Detailed Description
The invention is described in further detail below with reference to the accompanying examples.
The invention provides a ball screw assembly, as shown in the figure, it includes linear screw shaft 1 and cylindrical nut 2 screwed with screw shaft 1, the nut 2 is opened with grease filling hole (not shown) and grease overflow hole (not shown) communicating with the inner bore of the nut 2, the outer peripheral surface of the screw shaft 1 is continuous smooth surface, the outer peripheral surface of the screw shaft 1 has spiral first rolling groove 11, the inner peripheral surface of the nut 2 has spiral second rolling groove 21 with the same lead as the first rolling groove 11, the first rolling groove 11 and the second rolling groove 21 are opposite to form rolling channel, the rolling channel is provided with a plurality of balls 3, the nut 2 is screwed with the screw shaft 1 through the balls 3, the two axial inner diameter side ends of the nut 2 are opened with a ring-shaped concave base 22, the ring-shaped concave base 22 is installed with a sealing assembly 4 in ring shape, when the screw shaft 1 rotates, the sealing part of the sealing component 4 is always tightly attached to the outer peripheral surface of the screw shaft 1 to realize sealing connection; the sealing assembly 4 comprises a first fixing ring 41, a sealing ring 42 and a second fixing ring 43, the first fixing ring 41 is matched with the annular cavity seat 22, the first fixing ring 41 is provided with an annular groove 411, the sealing ring 42 and the second fixing ring 43 are just accommodated in the annular groove 411, the sealing ring 42 is pressed between the bottom of the annular groove 411 and the inner side shaft end face of the second fixing ring 43, the outer side shaft end face of the second fixing ring 43 is flush with the notch plane of the annular groove 411, the inner circumferential surface of the first fixing ring 41 and the inner circumferential surface of the second fixing ring 43 are in clearance fit with the outer circumferential surface of the screw shaft 1, the sealing ring 42 is used as a sealing part of the sealing assembly 4, the inner circumferential surface of the sealing ring 42 is in interference fit with the outer circumferential surface of the screw shaft 1, the inner circumferential surfaces of the first fixing ring 41, the sealing ring 42 and the second fixing ring 43 are always in tight fit, and the inclination angles of the first fixing ring 41 and the inclination angles of the first rolling groove 11 are consistent with each other The helical teeth 44. Here, the seal ring 42 is pressed between the first fixing ring 41 and the second fixing ring 43, and the seal ring 42 is prevented from being deformed by the fixing force of the first fixing ring 41 and the second fixing ring 43; the seal assembly 4 is mounted in the annular pocket 22, typically with the first retaining ring 41 on the inside and the second retaining ring 43 on the outside.
In the present embodiment, on a plane perpendicular to the axial direction of the screw shaft 1, the inner peripheral surface contour line of the first fixing ring 41 and the inner peripheral surface contour line of the second fixing ring 43 are radially equidistant from the outer peripheral surface contour line of the screw shaft 1, the circumferential length of the inner peripheral surface contour line of the first fixing ring 41 and the circumferential length of the inner peripheral surface contour line of the second fixing ring 43 are each 0.6 to 0.8mm, for example, 0.7mm, greater than the circumferential length of the outer peripheral surface contour line of the screw shaft 1, the inner peripheral surface contour line of the seal ring 42 is radially equidistant from the outer peripheral surface contour line of the screw shaft 1, and the circumferential length of the inner peripheral surface contour line of the seal ring 42 is less than 1.6 to 1.8mm, for example, less than 1.7 mm.
In this embodiment, four waist-shaped holes 421 are uniformly arranged on the sealing ring 42 along the circumferential direction, so as to meet the requirement of passing screws for compressing the sealing ring 42; a threaded hole corresponding to the position of the waist-shaped hole 421 is formed in the first fixing ring 41, a countersunk hole corresponding to the position of the waist-shaped hole 421 is formed in the second fixing ring 43, and a screw passes through the countersunk hole in the second fixing ring 43 and the waist-shaped hole 421 and then is screwed with the threaded hole in the first fixing ring 41.
In the present embodiment, the interference between the inner peripheral surface of the seal ring 42 and the outer peripheral surface of the threaded shaft 1 is set to 0.5 to 0.6mm, for example, 0.55mm, and the clearance between the inner peripheral surfaces of the first and second fixing rings 41 and 43 and the outer peripheral surface of the threaded shaft 1 is set to 0.20 to 0.25mm, for example, 0.22 mm. The interference magnitude is greater than the clearance magnitude, so that even if the seal ring 42 is rotated with the screw shaft 1 and fills the clearance between the first fixing ring 41, the second fixing ring 43, and the screw shaft 1, the seal ring 42 can be well secured to be closely attached to the outer peripheral surface of the screw shaft 1.
In the present embodiment, the annular cavity seat 22 is provided with positioning holes (not shown) on its peripheral wall. Here, the positioning hole is provided to firmly confine the first fixing ring 41 in the annular pocket seat 22, and the seal assembly 4 does not come off the end of the nut 2 on the inner diameter side in the case where the screw shaft 1 is operated at high speed.
In the present embodiment, the first fixing ring 41 and the second fixing ring 43 are made of a material with a relatively hard texture, such as polytetrafluoroethylene; the seal ring 42 is made of a material selected to maintain its shape under continuous high-speed operation of the threaded shaft 1, such as a fluorine rubber.
When this ball screw assembly is operated, the screw shaft 1 rotates, the nut 2 moves back and forth in the axial direction of the screw shaft 1, and due to the positional variation of the grease reservoir (inside the nut 2), part of the grease remains on the surface of the first rolling groove 11 of the screw shaft 1, and when this part of the screw shaft 1 passes through the seal unit 4, the seal ring 42 sweeps over the surface of the first rolling groove 11 of this part of the screw shaft 1, removes the grease, and blocks the grease in the nut 2.
Claims (9)
1. A ball screw assembly comprising a linear screw shaft and a cylindrical nut screwed to the screw shaft, characterized in that: the outer peripheral face of the screw shaft is a continuous smooth face, the end parts of the two inner diameter sides of the axial direction of the nut are respectively provided with an annular concave cavity seat, a sealing assembly which is integrally annular is installed in the annular concave cavity seats, and when the screw shaft rotates, the sealing part of the sealing assembly is tightly attached to the outer peripheral face of the screw shaft all the time to realize sealing connection.
2. A ball screw assembly according to claim 1, wherein: the outer peripheral surface of the screw shaft is provided with a spiral first rolling groove, the inner peripheral surface of the nut is provided with a spiral second rolling groove with the same lead as that of the first rolling groove, the first rolling groove and the second rolling groove are opposite to form a rolling channel, a plurality of balls are arranged in the rolling channel, and the nut is screwed with the screw shaft through the balls.
3. A ball screw assembly according to claim 2, wherein: the sealing assembly comprises a first fixing ring, a sealing ring and a second fixing ring, the first fixing ring is matched with the annular cavity seat, an annular groove is formed in the first fixing ring, the sealing ring and the second fixing ring are just accommodated in the annular groove, the sealing ring is pressed between the groove bottom of the annular groove and the inner side shaft end face of the second fixing ring, the outer side shaft end face of the second fixing ring is flush with the notch plane of the annular groove, the inner peripheral surface of the first fixing ring and the inner peripheral surface of the second fixing ring are in clearance fit with the outer peripheral surface of the screw shaft, the sealing ring is used as the sealing part of the sealing assembly, and the inner peripheral surface of the sealing ring is in interference fit with the outer peripheral surface of the screw shaft.
4. A ball screw assembly according to claim 3, wherein: on a plane perpendicular to the axial direction of the screw shaft, the inner peripheral surface contour line of the first fixing ring and the inner peripheral surface contour line of the second fixing ring are radially equidistant to the outer peripheral surface contour line of the screw shaft, the circumference of the inner peripheral surface contour line of the first fixing ring and the circumference of the inner peripheral surface contour line of the second fixing ring are both larger than the circumference of the outer peripheral surface contour line of the screw shaft by 0.6-0.8 mm, the inner peripheral surface contour line of the sealing ring is radially equidistant to the outer peripheral surface contour line of the screw shaft, and the circumference of the inner peripheral surface contour line of the sealing ring is smaller than the circumference of the outer peripheral surface contour line of the screw shaft by 1.6-1.8 mm.
5. The ball screw assembly of claim 4, wherein: the inner peripheral surface of the first fixed ring, the inner peripheral surface of the sealing ring and the inner peripheral surface of the second fixed ring are provided with spiral teeth with the inclination angle consistent with that of the first rolling groove.
6. The ball screw assembly of claim 4, wherein: a plurality of waist-shaped holes are uniformly formed in the circumferential direction on the sealing ring.
7. A ball screw assembly according to any one of claims 3 to 6, wherein: the interference between the inner circumferential surface of the seal ring and the outer circumferential surface of the screw shaft is 0.5 to 0.6mm, and the clearance between the inner circumferential surface of the first fixing ring and the inner circumferential surface of the second fixing ring and the outer circumferential surface of the screw shaft is 0.20 to 0.25 mm.
8. A ball screw assembly according to claim 3, wherein: the peripheral wall of the annular concave cavity seat is provided with a positioning hole.
9. A ball screw assembly according to claim 3, wherein: the nut is provided with a lubricating grease injection hole and a lubricating grease overflow hole which are communicated with the inner hole of the nut.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010392458.1A CN111609103A (en) | 2020-05-11 | 2020-05-11 | Ball screw pair |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010392458.1A CN111609103A (en) | 2020-05-11 | 2020-05-11 | Ball screw pair |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111609103A true CN111609103A (en) | 2020-09-01 |
Family
ID=72197729
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010392458.1A Pending CN111609103A (en) | 2020-05-11 | 2020-05-11 | Ball screw pair |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111609103A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117927650A (en) * | 2024-03-21 | 2024-04-26 | 成都道恒车辆技术有限公司 | Self-lubricating screw pair |
-
2020
- 2020-05-11 CN CN202010392458.1A patent/CN111609103A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117927650A (en) * | 2024-03-21 | 2024-04-26 | 成都道恒车辆技术有限公司 | Self-lubricating screw pair |
| CN117927650B (en) * | 2024-03-21 | 2024-05-28 | 成都道恒车辆技术有限公司 | Self-lubricating screw pair |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4482168B2 (en) | Ball screw sealing device | |
| US6095009A (en) | Ball screw having spacers | |
| US9500232B2 (en) | Ball bearing | |
| CN107532698B (en) | Ball screw | |
| JP5195434B2 (en) | Ball screw | |
| US3975968A (en) | Precision lead screw assembly and nut | |
| CN111609103A (en) | Ball screw pair | |
| CN107806516B (en) | Device comprising a sealing member | |
| JP2000035038A (en) | Direct acting guide unit equipped with lubricating plate | |
| CN212480039U (en) | Ball screw pair | |
| US20230220880A1 (en) | Follower bearing | |
| EP1852619B1 (en) | Oil lubricating roller bearing device | |
| JP4941134B2 (en) | Linear motion screw device | |
| EP3048337A1 (en) | Seal for ball-screw device | |
| JP2003166551A (en) | Angular contact ball bearing | |
| JP6809847B2 (en) | Sealing device | |
| JP2001304372A (en) | Ball screw apparatus | |
| JP2007225033A (en) | Ball screw | |
| EP1927797A1 (en) | Seal ring and seal structure | |
| JP2007321886A (en) | Ball screw device | |
| JP2012037063A (en) | Linear screw device | |
| CN108620936A (en) | A kind of scratch device and its manufacturing method for cleaning machine surface | |
| JP5961925B2 (en) | Ball screw device and manufacturing method thereof | |
| JP7124301B2 (en) | Four-point contact ball bearing and ball screw device provided with the same | |
| JP4985844B2 (en) | Ball screw device and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |