CN113819204B - Small-size high-bearing planetary roller screw - Google Patents

Small-size high-bearing planetary roller screw Download PDF

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Publication number
CN113819204B
CN113819204B CN202110916669.5A CN202110916669A CN113819204B CN 113819204 B CN113819204 B CN 113819204B CN 202110916669 A CN202110916669 A CN 202110916669A CN 113819204 B CN113819204 B CN 113819204B
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screw
ring
sleeve
roller
mounting
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CN202110916669.5A
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CN113819204A (en
Inventor
钱帅
黄建
段小帅
肖中卓
霍希建
李勇
刘天龙
王莹
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Beijing Automation Control Equipment Institute BACEI
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Beijing Automation Control Equipment Institute BACEI
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    • 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
    • F16H25/22—Screw mechanisms with balls, rollers, or similar members between the co-operating parts; Elements essential to the use of such members
    • F16H25/2247—Screw mechanisms with balls, rollers, or similar members between the co-operating parts; Elements essential to the use of such members with rollers
    • F16H25/2252—Planetary rollers between nut and screw
    • 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
    • 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
    • F16H2025/249—Special materials or coatings for screws or nuts

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Transmission Devices (AREA)

Abstract

The invention provides a small-sized high-bearing planetary roller screw which comprises an integrated nut sleeve (1), a screw rod (2), rollers (3), a first planetary carrier (4), a second planetary carrier (5), an annular gear (6), a retainer ring (7), an annular gear screw (8) and a retainer ring screw (9). The integral nut sleeve (1) combines the original sleeve and the nut into a whole, the check ring I and the annular gear I are removed, one end of the integral nut sleeve is ensured by the planetary carrier I (4) to ensure the relative position relationship between the rollers (3), and the other end of the integral nut sleeve is ensured by the planetary carrier II (5) and the annular gear II (6) to ensure the relative position relationship between the rollers (3). The thread shapes of the integral nut sleeve (1), the screw rod (2) and the roller (3) adopt 4 sections of circular arc thread shapes. The invention can obviously reduce the weight and the volume, can work with high efficiency under the working condition of heavy load, and simultaneously avoids the problems of rust, corrosion and seizing under the environments of salt fog and wet heat.

Description

Small-size high-bearing planetary roller screw
Technical Field
The invention belongs to the technical field of servo transmission mechanisms, and particularly relates to a planetary roller screw which is applied to an electromechanical actuator and can work in a narrow space, a heavy load working condition and a salt fog damp-heat environment.
Background
At present, the ball screw is widely applied to electromechanical actuators in the field of aerospace, and realizes the purpose of pushing the control surface of an aircraft to deflect. Planetary roller screws are gradually replacing the traditional ball screws by virtue of their high rigidity, high load bearing, high reliability, long service life and the like. Original planet roller lead screw includes: sleeve, nut, connecting screw, lead screw, I retaining ring, I ring gear screw, I planet carrier, roller, II retaining ring, II ring gear screw, II planet carrier and retaining ring screw. The transmission principle is as follows: the screw rod inputs the rotating speed and the torque, and the screw rod outer surface threads, the roller outer surface threads and the nut inner surface threads form thread rolling transmission, so that the nut outputs linear speed and thrust.
The original technical scheme has the following limitations: a) In order to facilitate the installation of the I check ring, the I inner gear ring and the I inner gear ring screw, the sleeve and the nut are arranged to be two independent parts, and are mutually nested and connected through the connecting screw, so that the radial dimension of the sleeve is larger, the total weight of the sleeve is heavier, the volume and the total weight of the electromechanical actuator are further increased, and the miniaturization and the realization of high power density of the electromechanical actuator are not facilitated; b) The screw rod outer surface threads, the roller outer surface threads and the nut inner surface threads are all in the shape of a conventional 60-degree triangle, deformation under a heavy load working condition is not considered, the transmission efficiency is low under the heavy load, and failure is easy to occur under the extreme load working condition; c) All parts are made of GCr15 bearing steel, and even if the surface is blackened, the parts cannot reliably work for a long time under the environments of salt fog and wet heat, are easy to rust and corrode, and are blocked.
Disclosure of Invention
The technical problem solved by the invention is to provide the small-sized high-bearing planetary roller screw rod, which can remarkably reduce the weight and the volume, can work with high efficiency under the working condition of heavy load, and simultaneously avoids the problems of rust, corrosion and seizing under the environments of salt fog and wet heat.
The utility model provides a small-size high planet roller screw that bears, includes sleeve, nut, lead screw 2, I planet carrier 4, II planet carrier 5, roller 3, ring gear 6, retaining ring 7, ring gear screw 8, retaining ring screw 9, its characterized in that includes: the sleeve and the nut are integrated into a nut sleeve 1.
Further, the integrated nut sleeve 1 comprises fine threads 10, a sleeve structure 11, a tool withdrawal groove 12, a guide square key 13, an inner gear ring installation threaded hole 14 and nut transmission threads 15; the fine thread 10 is connected with an external load; the sleeve structure 11 is used for accommodating axial movement of the screw rod 2; the tool retracting groove 12 is used for accommodating the first planet carrier 4; the guide square key 13 is arranged in a square groove of the electromechanical actuator shell, prevents the integral nut sleeve 1 from rotating along the axial direction, and guides the integral nut sleeve to move forwards and backwards along the axial direction; the ring gear mounting screw holes 14 provide a ring gear 6 mounting interface.
Further, the screw rod 2 comprises a weight reducing hole 16, screw rod transmission threads 17 and a support bearing mounting structure 18; wherein the lightening holes 16 are hollow; a support bearing mounting structure 18 for mounting a pair of thrust bearings;
the two ends of the roller 3 are provided with a first mounting post 19, a second mounting post 22 and a gear thread structure 21, wherein the first mounting post 19 is matched with a first roller mounting hole 26 on the first planet carrier 4, the second mounting post 22 is matched with a second roller mounting hole 27 on the second planet carrier 5, the gear thread structure 21 is meshed with an inner gear 25 arranged on the inner gear ring 6, and the relative position relationship between the rollers 3 is guaranteed;
the retainer ring 7 comprises a groove structure 28 and a countersunk through hole 29; wherein the groove structure 28 is for receiving the head of the ring gear screw 8; the countersunk through holes 29 are used for mounting the retainer screws 9.
Further, the thread shapes on the integrated nut sleeve 1, the screw rod 2 and the roller 3 are respectively composed of 4 sections of circular arcs R1, R2, R3 and R4; wherein R1 and R3 are tooth side bearing surfaces, and the radius value of R1 and R3 is 2-5 times of the screw pitch; r2 is a transition arc of the crest, and the radius of R2 is 1/30-1/100 of the pitch P; r4 is a root transition arc, and the radius of R4 is 1/30-1/100 of the pitch P; the tooth angle alpha takes the value of 55-45 degrees.
Further, the integral nut sleeve 1, the screw rod 2, the roller 3, the I planet carrier 4, the II planet carrier 5 and the annular gear 6 are made of 9Cr18 or 9Cr18MoV stainless steel materials, after the heat treatment hardness reaches HRC 56-HRC 60, the sizes of parts are processed in place, and finally, low-temperature ion nitriding treatment is carried out, wherein the nitriding temperature is 300-400 ℃, and the nitriding layer depth is 0.05-0.15 mm; the retainer ring 7, the annular gear screw 8 and the retainer ring screw 9 are made of stainless steel materials with carbon content less than 1.2%, and are subjected to surface passivation treatment after being processed in place.
The technical proposal has the beneficial effects that:
a) The sleeve and the nut in the original traditional planetary roller screw transmission mechanism are integrated, and a connecting screw is omitted. The improvement can greatly reduce the radial dimension, reduce the overall weight and increase the axial rigidity on the premise of the same performance.
b) After the check ring I and the annular gear I are removed, the original function of keeping the relative position relationship is not affected, the number of parts is simplified, the assembly complexity is reduced, and the improvement of the working reliability is facilitated.
c) The thread profile formed by the 4 sections of circular arcs can effectively avoid the clamping caused by the deformation of the threads under the heavy load and high temperature working conditions; compared with the traditional triangular thread, the limit bearing capacity of the 4-section circular arc thread can be obviously improved, and the bearing capacity of the 4-section circular arc thread is more than 1.5 times of that of the triangular thread.
d) After the 9Cr18 (or 9Cr18 MoV) stainless steel thread is subjected to low-temperature ion nitriding treatment, the hardness of the tooth surface can reach more than HRC65, the fatigue life of the thread surface can be remarkably prolonged, the corrosion resistance and the rust resistance can be improved, and the stainless steel thread can reliably work in salt fog and damp-heat environments.
Drawings
FIG. 1 is a diagram of the outline of a small-sized high-load planetary roller screw;
FIG. 2 is a three-dimensional cross-sectional view of a small high-load planetary roller screw;
FIG. 3 is a cross-sectional view of a small high-load planetary roller wire two-dimensional bar;
FIG. 4 is a schematic view of the internal structure of the integrated nut sleeve;
FIG. 5 is a diagram showing the outline of a screw;
FIG. 6 is a roller profile view;
fig. 7 is a schematic view of a thread profile.
Fig. 8 is an external view of the inner gear ring;
FIG. 9 is a plan view of the first carrier;
FIG. 10 is a plan view of a second carrier;
fig. 11 is a view of the outer shape of the retainer ring.
In the figure: 1-integral nut sleeve, 2-lead screw, 3-roller, 4-I planet carrier, 5-II planet carrier, 6-ring gear, 7-retainer ring, 8-ring gear screw, 9-retainer ring screw, 10-fine thread, 11-sleeve structure, 12-relief groove, 13-guide square key, 14-ring gear mounting threaded hole, 15-nut driving thread, 16-lightening hole, 17-lead screw driving thread, 18-support bearing mounting structure, 19-I mounting post, 20-roller driving thread, 21-gear threaded structure, 22-II mounting post, 23-ring gear mounting through hole, 24-retainer ring mounting threaded hole, 25-internal gear, 26-I roller mounting hole, 27-II roller mounting hole, 28-groove structure, 29-countersunk through hole
Disclosure of Invention
The invention will be further described with reference to the accompanying drawings and specific examples.
As shown in fig. 1, fig. 2 and fig. 3, the small-sized high-bearing planetary roller screw provided by the invention comprises: the nut comprises an integrated nut sleeve 1, a screw rod 2, rollers 3, a first planet carrier 4, a second planet carrier 5, an annular gear 6, a retainer ring 7, an annular gear screw 8 and a retainer ring screw 9.
The integral nut sleeve 1 combines the original sleeve and the nut, and meanwhile, the retainer ring I and the inner gear ring I are removed, one end of the integral nut sleeve is ensured by the planet carrier I4 to ensure the relative position relationship between the rollers 3, and the other end is ensured by the planet carrier II 5 and the inner gear ring 6 to ensure the relative position relationship between the rollers 3.
As shown in fig. 4, the integrated nut sleeve 1 includes: fine thread 10, sleeve structure 11, tool withdrawal groove 12, direction square key 13, ring gear installation screw hole 14, nut drive screw 15. Wherein the fine thread 10 functions to connect with an external load; the sleeve structure 11 has the function of an original sleeve, and the inside of the sleeve is used for accommodating the axial movement of the screw rod 2; the tool retracting groove 12 is a process structure reserved for processing the nut transmission thread 15 and has the function of accommodating the I-th planet carrier 4; the guiding square key 13 is installed in a square groove of the electromechanical actuator shell, prevents the integral nut sleeve 1 from rotating along the axial direction and guides the integral nut sleeve to move forwards and backwards along the axial direction; the function of the inner gear ring mounting threaded hole 14 is to provide a mounting interface for the inner gear ring 6; the enlarged thread profile on the nut drive thread 15 is shown in figure nine.
As shown in fig. 5, the screw 2 includes: a lightening hole 16, a screw drive screw 17 and a support bearing mounting structure 18. Wherein the lightening hole 16 is of a hollow structure for reducing moment of inertia during rotation and for reducing overall weight; the enlarged thread profile on the screw rod transmission thread 17 is shown in a ninth drawing; the support bearing mounting structure 18 is used to mount a pair of thrust bearings, such as a pair of angular contact bearings or a pair of tapered roller bearings.
As shown in fig. 6, 8, 9 and 10, the two ends of the roller 3 are provided with a first mounting post 19 at one end, a second mounting post 22 and a gear thread structure 21, the first mounting post 19 is matched with a first roller mounting hole 26 on the first planet carrier 4, the second mounting post 22 is matched with a second roller mounting hole 27 on the second planet carrier 5, and the gear thread structure 21 is meshed with an inner gear 25 arranged on the inner gear ring 6, so that the relative position relationship between the rollers 3 is guaranteed. The thread profile on the roller drive thread 20 is enlarged to be shown in figure nine.
As shown in fig. 7, the thread teeth in the integral nut sleeve 1, the screw rod 2 and the roller 3 are 4 sections of circular arcs (R 1 、R 2 、R 3 、R 4 ) Composition is prepared. Wherein R is 1 And R is R 3 Is a tooth side bearing surface R 1 And R is R 3 The value of (2) is 2-5 times of the pitch P. R is R 2 Is a transition arc of the crest of a tooth, R 2 The value is 1/30-1/100 of the pitch P. R is R 4 Is the transition arc of the root of the tooth, R 4 The value is 1/30-1/100 of the pitch P. The tooth angle alpha takes the value of 55-45 degrees.
As shown in fig. 11, the retainer ring 7 comprises a groove structure 28, a countersunk through hole 29. Wherein the groove structure 28 is for receiving the head of the ring gear screw 8; the countersunk through holes 29 are used for mounting the retainer screws 9.
The thread tooth shapes on the following 3 parts are all 4 sections of circular arcs R 1 、R 2 、R 3 、R 4 The composition is as follows: an integral nut sleeve 1, a screw rod 2 and a roller 3. Wherein R is 1 And R is R 3 Is a tooth side bearing surface R 1 And R is R 3 The radius of the pitch P is 2-5 times of the pitch P. R is R 2 Is a transition arc of the crest of a tooth, R 2 The radius is 1/30-1/100 of the pitch P. R is R 4 Is the transition arc of the root of the tooth, R 4 The radius is 1/30-1/100 of the pitch P. The tooth angle alpha takes the value of 55-45 degrees.
The following 6 parts: the integrated nut sleeve 1, the screw rod 2, the roller 3, the first planet carrier 4, the second planet carrier 5 and the inner gear ring 6 are made of 9Cr18 or 9Cr18MoV stainless steel, after the heat treatment hardness reaches HRC 56-HRC 60, the sizes of parts are machined in place, and finally, low-temperature ion nitriding treatment is carried out, wherein the nitriding temperature is 300-400 ℃, the nitriding layer depth is 0.05-0.15 mm, so that the tooth surface hardness is increased, the contact fatigue strength and the corrosion resistance are improved, the low-temperature ion nitriding deformation is small, and the screw shape precision is not affected. The following 3 parts: the retainer ring 7, the annular gear screw 8 and the retainer ring screw 9 are made of stainless steel materials with carbon content less than 1.2%, and are subjected to surface passivation treatment after being processed in place.

Claims (1)

1. The utility model provides a small-size high planet roller screw that bears, includes sleeve, nut, lead screw (2), I planet carrier (4), II planet carrier (5), roller (3), ring gear (6), retaining ring (7), ring gear screw (8), retaining ring screw (9), its characterized in that includes: the sleeve and the nut are integrated into a nut sleeve (1);
the integrated nut sleeve (1) comprises fine threads (10), a sleeve structure (11), a tool withdrawal groove (12), a guide square key (13), an inner gear ring installation threaded hole (14) and nut transmission threads (15); the fine thread (10) is connected with an external load; the sleeve structure (11) is used for accommodating axial movement of the screw rod (2); the tool retracting groove (12) is used for accommodating the I-th planet carrier (4); the guide square key (13) is arranged in a square groove of the electromechanical actuator shell, prevents the integral nut sleeve (1) from rotating along the axial direction, and guides the integral nut sleeve to move forwards and backwards along the axial direction; the inner gear ring mounting threaded hole (14) provides a mounting interface of the inner gear ring (6);
the screw rod (2) comprises a lightening hole (16), screw rod transmission threads (17) and a support bearing mounting structure (18); wherein the lightening hole (16) is of a hollow structure; a support bearing mounting structure (18) for mounting a pair of thrust bearings;
one end of each of two ends of each roller (3) is provided with a first mounting post (19), a second mounting post (22) and a gear thread structure (21), the first mounting post (19) is matched with a first roller mounting hole (26) on the first planet carrier (4), the second mounting post (22) is matched with a second roller mounting hole (27) on the second planet carrier (5), and the gear thread structure (21) is meshed with an inner gear (25) arranged on the inner gear ring (6) to jointly ensure the relative position relationship between the rollers (3);
the retainer ring (7) comprises a groove structure (28) and a countersunk through hole (29); wherein the groove structure (28) is used for accommodating the nail head of the ring gear screw (8); the countersunk through holes (29) are used for installing check ring screws (9);
the thread shapes of the integral nut sleeve (1), the screw rod (2) and the roller (3) are respectively composed of 4 sections of circular arcs R1, R2, R3 and R4; wherein R1 and R3 are tooth side bearing surfaces, and the radius value of R1 and R3 is 2-5 times of the screw pitch; r2 is a transition arc of the crest, and the radius of R2 is 1/30-1/100 of the pitch P; r4 is a root transition arc, and the radius of R4 is 1/30-1/100 of the pitch P; the tooth angle alpha takes the value of 55-45 degrees;
the integrated nut sleeve (1), the screw rod (2), the roller (3), the I planet carrier (4), the II planet carrier (5) and the inner gear ring (6) are made of 9Cr18 or 9Cr18MoV stainless steel materials, after the heat treatment hardness reaches HRC 56-HRC 60, the sizes of parts are processed in place, and finally, low-temperature ion nitriding treatment is carried out, wherein the nitriding temperature is 300-400 ℃, and the nitriding layer depth is 0.05-0.15 mm; the retainer ring (7), the annular gear screw (8) and the retainer ring screw (9) are made of stainless steel materials with carbon content less than 1.2%, and the surface passivation treatment is carried out after the dimension processing is in place.
CN202110916669.5A 2021-08-11 2021-08-11 Small-size high-bearing planetary roller screw Active CN113819204B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110916669.5A CN113819204B (en) 2021-08-11 2021-08-11 Small-size high-bearing planetary roller screw

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110916669.5A CN113819204B (en) 2021-08-11 2021-08-11 Small-size high-bearing planetary roller screw

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CN113819204A CN113819204A (en) 2021-12-21
CN113819204B true CN113819204B (en) 2023-06-13

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Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109667907A (en) * 2019-01-17 2019-04-23 苏春光 The planetary roller screw of ring grain axle sleeve matching thread screw rod
CN213655628U (en) * 2020-06-18 2021-07-09 北京精密机电控制设备研究所 Planetary roller screw with novel roller structure
CN111853191A (en) * 2020-08-11 2020-10-30 黄溧震 Nut type gearless constant lead planetary roller screw
CN112049908A (en) * 2020-09-18 2020-12-08 中国船舶重工集团公司第七0四研究所 Planetary roller screw of gear transmission mode
CN212536572U (en) * 2020-09-18 2021-02-12 中国船舶重工集团公司第七0四研究所 Ring gear nut planet roller screw
CN112460217A (en) * 2020-11-09 2021-03-09 北京精密机电控制设备研究所 Novel planet roller lead screw
CN112413076A (en) * 2020-11-25 2021-02-26 山东博特精工股份有限公司 Differential planetary roller screw pair

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