CN111102340A - Harmonic gear speed reducer - Google Patents

Harmonic gear speed reducer Download PDF

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Publication number
CN111102340A
CN111102340A CN201811265598.1A CN201811265598A CN111102340A CN 111102340 A CN111102340 A CN 111102340A CN 201811265598 A CN201811265598 A CN 201811265598A CN 111102340 A CN111102340 A CN 111102340A
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CN
China
Prior art keywords
grooves
row
gear
teeth
rigid
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Withdrawn
Application number
CN201811265598.1A
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Chinese (zh)
Inventor
杨敬明
苏文政
姚景彬
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Simplo Technology Co Ltd
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Simplo Technology Co Ltd
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Priority to CN201811265598.1A priority Critical patent/CN111102340A/en
Publication of CN111102340A publication Critical patent/CN111102340A/en
Withdrawn legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16HGEARING
    • F16H49/00Other gearings
    • F16H49/001Wave gearings, e.g. harmonic drive transmissions

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Retarders (AREA)

Abstract

The invention provides a harmonic gear speed reducer, which comprises a rigid gear, a flexible gear and a wave generator. The rigid wheel has a plurality of internal teeth. The flexible gear is arranged in the rigid gear and comprises a cylinder body and a plurality of external teeth. The outer teeth are attached to a first side of the barrel and the outer teeth engage the inner teeth. The wave generator is arranged in the flexible gear. And a plurality of grooves are formed on the cylinder body and are arranged into at least one row, and the grooves of the at least one row are discontinuously arranged around the periphery of the cylinder body. Therefore, discontinuous elastic deformation is generated at the positions of the grooves, so that the outward expansion inclination angle of the cylinder body of the flexible gear is slowed down, and the effect of increasing the meshing area of the rigid-flexible gear teeth is achieved.

Description

Harmonic gear speed reducer
Technical Field
The invention relates to a harmonic gear reducer, in particular to a harmonic gear reducer with an improved flexible gear.
Background
The harmonic gear reducer is a transmission device with the advantages of high precision, small back clearance, high reduction ratio, light weight, small volume, large bearing capacity, high efficiency and the like, and is widely used on precision machines and tools such as spaceflight, robots, tool machines, optical instruments and the like. In addition, a solar rotation structure may also be applied.
Fig. 1 shows an exploded view of a known harmonic gear reducer. As shown in fig. 1, a conventional harmonic gear reducer 100 mainly includes a rigid gear 101, a flexible gear 103, and a wave generator 102 (or wave generator). The inner ring surface of the rigid gear 101 includes an inner tooth portion 111 formed with a plurality of inner teeth. The outer circumferential surface of the flexspline 103 includes an external tooth portion 112 formed with a plurality of external teeth. The internal teeth 111 are engaged with the external teeth 112 in a meshing transmission manner, and the wave generator 102 is rotatably provided in the flexspline 103. The wave generator 102 includes a cam 130 and a bearing 140 provided outside the cam 130.
Fig. 2 shows a plan view of a conventional harmonic gear reducer. As shown in fig. 2, the wave generator 102 has a generally elliptical contour shape and is coupled to a power source, and when the power source rotates, the inner wall of the flexible gear 103 is deformed by being coupled to the outer peripheral contour of the wave generator 102, so that the inner tooth portion 111 of the rigid gear 101 and the outer tooth portion 112 of the flexible gear 103 are completely engaged with each other at the major axis of the wave generator 102 and completely disengaged from each other at the minor axis of the wave generator 102. Because there is a difference in the number of teeth between the internal tooth portion 111 of the ring gear 101 and the external tooth portion 112 of the flexspline 103, a high reduction ratio is achieved when the power source continues to operate.
The harmonic gear reducer 100 works on the principle that the flexible gear 103 (i.e., the flexible external gear) deforms due to the contour shape of the wave generator 102, so that the flexible gear 103 and the rigid gear 101 (i.e., the rigid internal gear) are completely meshed at the long axis of the wave generator 102, and the effect of power transmission and speed reduction is achieved. The flexible gear 103 is typically designed as a thin-walled cylindrical object, and when the wave generator 102 is inserted into the cylindrical inner hole of the flexible gear 103, the outer peripheral contour of the wave generator 102 is combined with the inner wall of the flexible gear 103. The cylindrical barrel body of the flexible gear 103 is in an outward-expanding horn mouth shape at the long axis of the wave generator 102; on the other hand, the short axis of the wave generator 102 is in a shape of a horn mouth which is retracted inwards. Therefore, the tooth-like meshing of the rigid-flexible gear with the long axis of the wave generator 102 is not a meshing contact of all teeth in the axial direction.
Fig. 3 shows a schematic view of the meshing areas of the internal teeth of the rigid wheel and the external teeth of the flexible wheel according to the known art. More specifically, as shown in fig. 3, the external teeth 112 of the flexspline 103 mesh with the internal teeth 111 formed on the inner side surface of the rigid spline 101. The cylindrical body of the flexspline 103 is flared, the surfaces of the flexspline 103 and the internal tooth portions 111 form an inclination angle θ, and the external tooth portions 112 of the flexspline 103 and the internal tooth portions 111 of the circular spline 101 cannot be brought into full-tooth meshing contact in the meshing region a. In this specification, the meshing contact of the single tooth portion in the axial direction is referred to as a meshing region a.
According to the U.S. patent nos. US5269202A and US5715732A, the cylinder of the flexible gear and the outer edge of the connecting surface are designed in a multi-step curve, that is, the thickness of the cylinder of the flexible gear is different for each step. Fig. 4 shows a schematic view of the meshing areas of the internal teeth of the rigid wheel and the external teeth of the flexible wheel according to the known art. As shown in fig. 4, according to chinese patent publication No. CN103649586A, a rigid internally-toothed gear 2 (rigid gear) includes internal teeth 24. The flexible externally toothed gear 3 includes external teeth 36. In the cylindrical barrel part 31 of the flexible externally toothed gear 3 (flexspline), the externally toothed portion 37 includes a pushed portion 38a, an adjacent portion 38b, and a tip portion 38 c. A single groove 38d having a certain width is formed at a portion of the abutting portion 38b adjacent to the pressed portion 38 a. The groove 38d extends around the entire circumference on the inner peripheral surface of the external teeth forming portion 37.
However, the conventional structure still has a room for further improvement, and therefore how to increase the meshing area of the teeth of the rigid gear 101 and the flexible gear 103 to improve the rigidity, the transmission precision and the service life of the speed reducer is a common problem in the field of the harmonic gear speed reducer 100.
Disclosure of Invention
The invention aims to provide a harmonic gear reducer, wherein a flexible gear has an improved structure so as to increase the meshing contact between an external tooth part of the flexible gear and an internal tooth part of a rigid gear, and at least one of the rigidity, the transmission precision and the service life of the reducer can be improved.
According to an embodiment of the present invention, a harmonic gear reducer is provided, which includes a rigid gear, a flexible gear and a wave generator. The rigid wheel is provided with a plurality of internal teeth, and the flexible wheel is arranged in the rigid wheel and comprises a cylinder body and a plurality of external teeth. The outer teeth are attached to a first side of the barrel and the outer teeth engage the inner teeth. The wave generator is arranged in the flexible gear. And a plurality of grooves are formed on the cylinder body and are arranged into at least one row, and the grooves of the at least one row are discontinuously arranged around the periphery of the cylinder body.
In one embodiment, the at least one row of grooves includes a first row of grooves and a second row of grooves, the grooves include a plurality of first grooves and a plurality of second grooves, the first grooves are discontinuously arranged into the first row of grooves, the second grooves are discontinuously arranged into the second row of grooves, and a first groove is formed in each of the first row of grooves corresponding to each of the spaces between two adjacent second grooves. Preferably, one second trench is formed in the second row of trenches at a position corresponding to each interval between two adjacent first trenches.
In one embodiment, the flexspline further comprises a Flange (Flange) connected to a second side of the cylinder, the second side being opposite to the first side.
In one embodiment, the length of each second trench is greater than the length of the space between two adjacent first trenches. In one embodiment, the length of each first trench is greater than the length of the space between two adjacent second trenches. Preferably, the first grooves and the second grooves are arranged continuously when projected on the surface of the flange.
In one embodiment, the grooves are closer to the outer teeth than to the flange.
In one embodiment, the barrel has a uniform thickness. Preferably, each of these grooves extends through the entire thickness of the barrel.
According to an embodiment of the present invention, a plurality of grooves are formed on the cylinder of the flexspline, and the grooves are arranged in at least one row, and the grooves of the at least one row are discontinuously arranged around the outer circumference of the cylinder. Therefore, discontinuous elastic deformation is generated at the positions of the grooves, so that the outward expansion inclination angle of the cylinder body of the flexible gear is slowed down, and the effect of increasing the meshing area of the rigid-flexible gear teeth is achieved.
Drawings
The drawings are only for purposes of illustrating and explaining the present invention and are not to be construed as limiting the scope of the present invention. Wherein:
fig. 1 shows an exploded view of a known harmonic gear reducer.
Fig. 2 shows a plan view of a conventional harmonic gear reducer.
Fig. 3 shows a schematic view of the meshing areas of the internal teeth of the rigid wheel and the external teeth of the flexible wheel according to the known art.
Fig. 4 shows a schematic view of the meshing areas of the internal teeth of the rigid wheel and the external teeth of the flexible wheel according to the known art.
Fig. 5 is a cross-sectional view of a harmonic gear reducer according to an embodiment of the present invention.
Fig. 6 is a schematic diagram illustrating an engagement area of a harmonic gear reducer according to an embodiment of the present invention.
Fig. 7 shows a schematic view of the meshing areas of the internal teeth of the rigid wheel and the external teeth of the flexible wheel according to the known art.
Main element number description:
2: rigid internally toothed gear
3: flexible external gear
24: internal tooth
31: main body part
36: external tooth
37: external tooth forming part
38 a: pushed part
38 b: abutment portion
38 c: front end side portion
38 d: trough
100: harmonic gear speed reducer
101: rigid wheel
102: wave generator
103: flexible gear
111: internal tooth system
112: external tooth
130: cam wheel
140: bearing assembly
14 a: first trench
14 b: second trench
200: speed reducer
201: rigid wheel
202: flexible gear
203: wave generator
211: internal tooth
212: external tooth
213: barrel body
214: groove
215: flange
A: engaging zone
Detailed Description
To solve the above problems, according to an embodiment of the present invention, the circular but discontinuous fine grooves are cut in the cylindrical body of the flexible gear cylinder, and when the wave generator is inserted into the inner hole of the flexible gear cylinder, the cylindrical body of the flexible gear cylinder is restrained by the outer peripheral contour of the wave generator, so that the cylindrical body is in the form of an outwardly expanded bell mouth at the long axis of the wave generator. At the moment, the flexible wheel cylinder body is provided with the circular arrangement thin grooves, so that the cylinder body with the outward expansion flexible wheel generates discontinuous elastic deformation at the positions of the grooves, and further the outward expansion inclination angle of the flexible wheel cylinder body is slowed down, and the effect of increasing the meshing area of the teeth of the rigid and flexible wheels is achieved. The present invention will be described in detail below with reference to the attached drawings, wherein like reference numerals will be used to identify identical or similar elements from multiple viewpoints. It should be noted that the drawings should be viewed in the direction of the orientation of the reference numerals.
Fig. 5 is a cross-sectional view of a harmonic gear reducer according to an embodiment of the present invention. As shown in fig. 5, the harmonic gear reducer 200 includes a rigid gear 201, a flexible gear 202, and a wave generator 203. The inner side of the rigid wheel 201 includes (has) a plurality of internal teeth 211 for meshing. The flexspline 202 is disposed within the rigid spline 201 and includes (has) on its outside a plurality of external teeth 212 for engagement, the external teeth 212 partially engaging the internal teeth 211. The wave generator 203 is disposed in the flexspline 202.
Fig. 6 is a schematic diagram illustrating an engagement area of a harmonic gear reducer according to an embodiment of the present invention. As shown in fig. 5 and 6, the flexible spline 202 includes a flange 215, a barrel 213 and a plurality of external teeth 212. The flange may also be referred to as a flange or flange. Barrel 213 is attached to flange 215 and is positioned between flange 215 and outer teeth 212. A first side of barrel 213 is attached to outer teeth 212 and a second side of barrel 213 is attached to flange 215. barrel 213 has a uniform thickness. The cylindrical body 213 of the flexspline 202 may be cylindrical and may be fitted around the wave generator 203 to form a flared bell. In the present embodiment, in order to make the internal teeth 211 and the external teeth 212 mesh relatively completely, that is, to make most of the meshing portions of the internal teeth 211 and the external teeth 212 fit into each other, a plurality of grooves 214 are formed in a first side portion of the barrel 213 close to the external teeth 212, and a row of the grooves 214 is discontinuous around the outer circumference of the first side of the barrel 213. According to this design, the meshing area can be increased, and the rigidity of the flexspline can be maintained, so that the harmonic reducer 200 can smoothly rotate.
Fig. 7 shows a schematic view of the meshing areas of the internal teeth of the rigid wheel and the external teeth of the flexible wheel according to the known art. As shown in fig. 7, since the outer circumference of the first side of the barrel 213 is formed with a plurality of rows of grooves 214, and each row of grooves 214 is discontinuous, a soft region or a bending region is provided, so as to slow down the outward-expanding inclination angle of the barrel 213 of the flexible gear 202, so that the outer teeth 212 of the flexible gear 202 and the inner teeth 211 of the rigid gear 201 can be engaged relatively completely in the engagement region a.
In the present embodiment, each groove 214 is located in the region outside the outer teeth 212, so as to avoid generating unexpected deformation at the position of the outer teeth 212. Preferably, groove 214 extends through the entire thickness of barrel 213, thereby increasing the flexibility of barrel 213 and increasing the area of engagement area A.
Referring to fig. 6 again, the trenches 214 include a plurality of first trenches 14a and a plurality of second trenches 14 b. The first grooves 14a are discontinuously arranged in a first row and are circumferentially arranged on the outer periphery of the first side of the barrel 213, and the second grooves 14b are discontinuously arranged in a second row and are circumferentially arranged on the outer periphery of the first side of the barrel 213. Moreover, the first grooves 14a in the first row of grooves are closer to the outer teeth 212 than the second grooves 14b in the second row of grooves.
In one embodiment, a second trench 14b is formed in the second row of trenches at a position corresponding to the interval between two adjacent first trenches 14a, and the length of the second trench 14b is greater than the length of the interval between two adjacent first trenches 14 a. In addition, a first groove 14a may be formed at a position of the first row of grooves corresponding to each interval between two adjacent second grooves 14b, and the length of the first groove 14a is greater than the length of the interval between two adjacent second grooves 14 b. According to the above design, it is preferable that the first grooves 14a and the second grooves 14b are continuously arranged when being projected on the surface of the flange 215. Preferably, the first grooves 14a and the second grooves 14b penetrate the entire thickness of the barrel 213, so that the spaces between two adjacent first grooves 14a, the spaces between two adjacent second grooves 14b, and the spaces between the first grooves 14a and the second grooves 14b can be utilized to generate deformation, thereby increasing the flexibility of the barrel 213 and increasing the area of the engagement area a.
As described above, according to an embodiment of the present invention, a harmonic gear reducer can be provided, which can increase the tooth meshing area of the rigid and flexible gears, thereby improving the working efficiency of the reducer, such as rigidity, transmission accuracy, and life. In one embodiment, circular but discontinuous thin strip-shaped grooves 214 are cut in the cylindrical barrel 213 of the flexible gear 202, and after the wave generator 203 is inserted into the inner hole of the cylindrical barrel 213 of the flexible gear 202, the barrel 213 is constrained by the outer peripheral contour of the wave generator 203, so that the barrel 213 is flared at the long axis of the wave generator 203. At this time, the cylindrical body 213 has the annular thin grooves 214, so the cylindrical body 213 of the flexspline 202 is deformed discontinuously at the positions of the grooves 214, and the outward-expanding inclination angle of the cylindrical body 213 of the flexspline 202 is reduced, thereby achieving the effect of increasing the meshing area of the rigid and flexible gear teeth.
Having described the invention in detail, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention. Any equivalent changes and modifications that can be made by one skilled in the art without departing from the spirit and principles of the invention should be considered within the scope of the invention. It should be noted that the components of the present invention are not limited to the above-mentioned whole application, and various technical features described in the present specification can be selected to be used alone or in combination according to actual needs, so that the present invention naturally covers other combinations and specific applications related to the invention.

Claims (9)

1. A harmonic gear reducer, comprising:
a rigid wheel having a plurality of internal teeth;
a flexible gear disposed within the rigid gear, comprising:
a barrel body; and
a plurality of external teeth connected to a first side of the barrel, the external teeth engaging with the internal teeth; and
the wave generator is arranged in the flexible gear;
the cylinder body is provided with a plurality of grooves, the grooves are arranged into at least one row, and the grooves of the at least one row are discontinuously arranged around the periphery of the cylinder body.
2. The harmonic gear reducer of claim 1,
the at least one row of grooves includes a first row of grooves and a second row of grooves, and
the trench includes:
a plurality of first grooves arranged discontinuously in the first row of grooves,
a plurality of second grooves arranged discontinuously in the second row of grooves,
wherein, a first groove is formed on the first row of grooves corresponding to each interval between two adjacent second grooves.
3. The harmonic gear reducer of claim 2,
and one second groove is formed in the position, corresponding to each interval between two adjacent first grooves, of the second row of grooves.
4. The harmonic gear reducer of claim 3,
the flexspline further comprises:
and the flange is connected to a second side of the cylinder body, and the second side is opposite to the first side.
5. The harmonic gear reducer according to claim 4, wherein a length of each of said second grooves is greater than a length of said space between two adjacent said first grooves.
6. The harmonic gear reducer of claim 5,
the length of each first groove is greater than the length of the space between two adjacent second grooves, and
the plurality of first grooves and the plurality of second grooves are arranged continuously when projected on the surface of the flange.
7. The harmonic gear reducer as in claim 4 wherein the plurality of grooves are closer to the plurality of external teeth relative to the flange.
8. The harmonic gear reducer as in any one of claims 1-7, wherein the barrel has a uniform thickness.
9. The harmonic gear reducer as in claim 8 wherein each of the plurality of grooves extends through the entire thickness of the barrel.
CN201811265598.1A 2018-10-29 2018-10-29 Harmonic gear speed reducer Withdrawn CN111102340A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113683000A (en) * 2021-08-31 2021-11-23 山东塞克尔矿山设备有限公司 Piston type pneumatic hoist

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3815118A1 (en) * 1988-05-04 1989-11-16 Festo Kg Stress wave gearing
DE29622185U1 (en) * 1996-12-20 1998-07-30 Hirn Marliese Reduction gear
CN202746501U (en) * 2012-08-07 2013-02-20 锕玛科技股份有限公司 Transmission structure for harmonic wave transmission device
CN202914703U (en) * 2012-09-14 2013-05-01 锕玛科技股份有限公司 Clearance compensation structure of harmonic transmission device
JP2014092208A (en) * 2012-11-01 2014-05-19 Jtekt Corp Wave gear device, and transmission ratio variable device
CN106090183A (en) * 2016-07-29 2016-11-09 柳州福能机器人开发有限公司 The decelerator flexbile gear of intelligent industrial robot
CN108253091A (en) * 2016-12-29 2018-07-06 财团法人工业技术研究院 Harmonic drive
JP2018115693A (en) * 2017-01-17 2018-07-26 株式会社ジェイテクト Wave motion gear device

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3815118A1 (en) * 1988-05-04 1989-11-16 Festo Kg Stress wave gearing
DE29622185U1 (en) * 1996-12-20 1998-07-30 Hirn Marliese Reduction gear
CN202746501U (en) * 2012-08-07 2013-02-20 锕玛科技股份有限公司 Transmission structure for harmonic wave transmission device
CN202914703U (en) * 2012-09-14 2013-05-01 锕玛科技股份有限公司 Clearance compensation structure of harmonic transmission device
JP2014092208A (en) * 2012-11-01 2014-05-19 Jtekt Corp Wave gear device, and transmission ratio variable device
CN106090183A (en) * 2016-07-29 2016-11-09 柳州福能机器人开发有限公司 The decelerator flexbile gear of intelligent industrial robot
CN108253091A (en) * 2016-12-29 2018-07-06 财团法人工业技术研究院 Harmonic drive
JP2018115693A (en) * 2017-01-17 2018-07-26 株式会社ジェイテクト Wave motion gear device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113683000A (en) * 2021-08-31 2021-11-23 山东塞克尔矿山设备有限公司 Piston type pneumatic hoist

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Application publication date: 20200505