阅读说明：本技术 一种单向平面扭簧 (One-way plane torsional spring ) 是由 李兵 刘一帆 宁英豪 黄海林 徐文福 杨晓钧 林峰 于 2019-09-11 设计创作，主要内容包括：本发明提供了一种单向平面扭簧,包括扭簧外圈、扭簧内圈以及多个扭簧弹性体；扭簧内圈位于扭簧外圈的内侧,并且扭簧外圈与扭簧内圈之间存在间隙,多个扭簧弹性体分布在扭簧外圈与扭簧内圈之间的间隙中,其中扭簧弹性体从扭簧外圈的内周面引出,沿着扭簧内圈的外周方向以环绕曲线为延伸基准,延展连接至扭簧内圈的外周面,扭簧内圈的外周面设有抵接部,扭簧外圈的内周面设有与抵接部配合的止挡部,并且止挡部位于扭簧弹性体切线方向的正方向前方。本发明的单向平面扭簧一方面增大了平面扭簧中扭簧内圈、扭簧外圈的单向相对转动角度,另一方面平面扭簧中扭簧内圈、扭簧外圈相对转动时的整体刚度基本不变,具有结构简单、实用性强的优点。(The invention provides a one-way plane torsion spring which comprises a torsion spring outer ring, a torsion spring inner ring and a plurality of torsion spring elastic bodies; the torsional spring inner circle is located the inboard of torsional spring outer lane, and there is the clearance between torsional spring outer lane and the torsional spring inner circle, a plurality of torsional spring elastomers distribute in the clearance between torsional spring outer lane and torsional spring inner circle, wherein the torsional spring elastomer is drawn forth from the inner peripheral surface of torsional spring outer lane, use the surrounding curve as the extension benchmark along the peripheral direction of torsional spring inner circle, the extension is connected to the outer peripheral face of torsional spring inner circle, the outer peripheral face of torsional spring inner circle is equipped with butt portion, the inner peripheral surface of torsional spring outer lane be equipped with butt portion complex backstop portion, and backstop portion is. The one-way planar torsion spring increases the one-way relative rotation angle of the inner ring and the outer ring of the torsion spring in the planar torsion spring, and has the advantages of simple structure and strong practicability because the overall rigidity is basically unchanged when the inner ring and the outer ring of the torsion spring in the planar torsion spring rotate relatively.)

1. A one-way planar torsion spring, comprising:

An outer ring of a torsion spring;

the inner ring of the torsion spring is positioned on the inner side of the outer ring of the torsion spring, and a gap is formed between the outer ring of the torsion spring and the inner ring of the torsion spring;

the torsional spring elastic bodies are distributed in a gap between the outer ring of the torsional spring and the inner ring of the torsional spring;

The torsion spring elastic body is led out from the inner peripheral surface of the torsion spring outer ring, and extends and is connected to the outer peripheral surface of the torsion spring inner ring along the outer peripheral direction of the torsion spring inner ring by taking a surrounding curve as an extension reference;

the outer circumferential surface of the inner ring of the torsion spring is provided with a butting part, the inner circumferential surface of the outer ring of the torsion spring is provided with a stopping part matched with the butting part, and the stopping part is positioned in the forward direction of the tangent direction of the elastic body of the torsion spring.

2. The unidirectional planar torsion spring of claim 1, wherein the encircling curve of the torsion spring elastomer is a planar spiral.

3. The unidirectional planar torsion spring according to claim 1, wherein a plurality of the torsion spring elastomers located between the outer and inner races of the torsion spring are distributed in a circular array or are oppositely disposed.

4. The unidirectional planar torsion spring of claim 1, wherein the minimum distance between any point of the torsion spring elastomer and the outer coil of the torsion spring is set not to exceed the minimum distance between the point and the inner coil of the torsion spring.

5. The unidirectional planar torsion spring of claim 4, wherein the ratio of the distance between any point of the torsion spring elastomer and the minimum distance between the point and the inner ring of the torsion spring is 1: 1-1: 5.

6. The unidirectional planar torsion spring according to claim 1, wherein the number of the torsion spring elastic bodies is two or more.

7. The unidirectional planar torsion spring according to claim 1, wherein the abutting portion has an abutting arc surface protruding toward the outer circumferential surface of the inner race of the torsion spring, and the stopper portion has a stopper arc surface engaged with the abutting arc surface, and the abutting arc surface is engaged with the stopper arc surface in line-line abutting engagement.

8. The unidirectional planar torsion spring according to claim 1, wherein the abutting portion has an abutting flat surface formed to protrude toward the outer circumferential surface of the inner race of the torsion spring, and the stopper portion has a stopper flat surface engaged with the flat surface, and the abutting flat surface is engaged with the stopper flat surface in surface-to-surface abutting.

9. The unidirectional planar torsion spring according to claim 1, wherein the abutting portion is provided with a first groove, and the first groove is communicated or not communicated with the gap between the outer ring of the torsion spring and the inner ring of the torsion spring; the stopping part is provided with a second groove, and the second groove is communicated with the gap between the outer ring of the torsion spring and the inner ring of the torsion spring or is not communicated with the gap between the outer ring of the torsion spring and the inner ring of the torsion spring.

10. the unidirectional planar torsion spring according to claim 1, wherein the inner circumferential surface of the inner torsion spring ring and the outer circumferential surface of the outer torsion spring ring are provided with connecting key grooves.

Technical Field

the invention belongs to the technical field of robots, and particularly relates to a one-way planar torsion spring.

background

in recent years, systems for establishing secure interaction between humans and robots have been implemented by means of impedance control, sensor sensing, series connection of elastic actuators, and the like. The joint driven by the series elastic force has better impact resistance, so that the joint has flexibility in mechanical structure and is widely applied.

The flexible joint based on the characteristics of the planar torsion spring realizes the flexibility of the joint by means of the relative rotation of the inner ring and the outer ring and the deformation of the elastic part, the structural form of the planar torsion spring mainly comprises the structures of the inner ring of the torsion spring, the outer ring of the torsion spring and the middle elastic body of the torsion spring, the flexible joint based on the characteristics of the planar torsion spring realizes the flexibility of the joint by means of the relative rotation of the inner ring and the outer ring of the torsion spring, and the elastic body deforms.

In the development of applying a torsion spring to a joint, a variable stiffness joint (publication No. CN105345839A) based on the characteristics of the torsion spring is proposed by Yankee and the like of Harbin university of industry, and a double-series elastic driver (publication No. CN101318331A) is proposed by the Wangliang and the like of Harbin university of engineering, wherein the torsion springs are traditional spiral springs, and the compactness of the joint structure of the robot is difficult to realize.

The planar torsion spring (publication number CN102632508A) suitable for the robot joint is provided by Zhu and autumn, etc. at university of Zhejiang, the planar torsion spring suitable for the robot joint is developed for the first time at home, and the problems of large occupied space and loose structure of the traditional torsion spring are solved.

Forest crowd you, etc. at university of Zhejiang disclose a planar torsion spring (publication number CN103836101A) with flexible joints, aiming to improve the maximum torque value and the relative rotation angle, and simultaneously, a limit cable is added to protect the planar torsion spring.

The working mode of the planar torsion spring is generally that when the joint is driven in the positive direction, the inner ring drives the elastic part to deform in the positive direction, and when the generated torque is larger than the load torque, the outer ring rotates in the positive direction; when the joint is driven reversely, the inner ring rotates reversely to drive the elastic part to return to the balance position, and then continuously rotates reversely to deform, and when the generated torque is larger than the load torque, the outer ring is driven to rotate reversely.

Disclosure of Invention

aiming at the defects of the prior art, the invention provides a one-way planar torsion spring, which increases the one-way relative rotation angle of an inner ring and an outer ring of the torsion spring in the planar torsion spring on one hand, and keeps the integral rigidity basically unchanged when the inner ring and the outer ring of the torsion spring rotate relatively in the planar torsion spring on the other hand, and has simple structure and strong practicability.

In order to achieve the above object, the present invention provides a unidirectional planar torsion spring, comprising a torsion spring outer ring, a torsion spring inner ring and a plurality of torsion spring elastic bodies; the torsional spring inner circle is located the inboard of torsional spring outer lane, and there is the clearance between torsional spring outer lane and the torsional spring inner circle, a plurality of torsional spring elastomers distribute in the clearance between torsional spring outer lane and torsional spring inner circle, wherein the torsional spring elastomer is drawn forth from the inner peripheral surface of torsional spring outer lane, use the surrounding curve as the extension benchmark along the peripheral direction of torsional spring inner circle, the extension is connected to the outer peripheral face of torsional spring inner circle, the outer peripheral face of torsional spring inner circle is equipped with butt portion, the inner peripheral surface of torsional spring outer lane be equipped with butt portion complex backstop portion, and backstop portion is.

In the above technical solution of the present invention, the encircling curve is a curve extending along the outer circumference of the inner ring of the torsion spring in one direction, that is, the positive direction of the tangential direction of the encircling curve is always unchanged (for example, clockwise or counterclockwise), and the encircling angle is selected according to the design requirement. The extension reference refers to the main outline direction presented by the projection of the torsion spring elastic body, and does not limit the specific shape of the torsion spring elastic body.

furthermore, after the inner ring and the outer ring of the torsion spring relatively rotate to a set angle range (the elastic body of the torsion spring can deform and store energy to realize the flexibility of the joint in the process), the abutting part can be contacted with the stopping part and is limited by the stopping part, and the effects of limiting and protecting the torsion spring structure are achieved; at this time, the engagement between the stopper portion and the abutting portion prevents the torsion spring elastic body from further deforming, so that the stiffness of the planar torsion spring is sharply increased to approximately exhibit rigidity.

According to another embodiment of the present invention, the encircling curve of the torsion spring elastic body is a planar spiral line, wherein the number of the torsion spring elastic bodies is two or more, for example, M (M is an integer greater than or equal to 2), preferably, the M torsion spring elastic bodies are uniformly distributed on the circumference of the inner ring of the torsion spring or are arranged oppositely, and the stiffness of the torsion spring as a whole can be changed by selecting different M values; the external expansion rate and the termination position of the torsion spring elastic body can be adjusted by changing the pitch p and the number q of turns of the plane spiral line, so that the structure of the torsion spring inner ring and the torsion spring outer ring with different sizes is adapted, and particularly, the wall thickness of the torsion spring elastic body can be adjusted according to specific requirements so as to better adapt to the requirements for different rigidity.

According to another specific embodiment of the invention, the minimum distance between any position point of the elastic body of the torsion spring and the outer ring of the torsion spring is set to be not more than the minimum distance between the position point and the inner ring of the torsion spring.

Further, the distance ratio between the minimum distance between any position point of the torsion spring elastic body and the outer ring of the torsion spring and the minimum distance between the position point and the inner ring of the torsion spring is 1: 1-1: 5, for example, the distance ratio between the two is 1: 2.

According to another embodiment of the present invention, the abutting portion has an abutting arc surface protruding toward the outer peripheral surface of the inner ring of the torsion spring, the stopper portion has a stopper arc surface engaged with the abutting arc surface, and the abutting arc surface and the stopper arc surface are engaged in line-to-line abutting.

The arc surface structural style between butt joint portion and the backstop portion in this scheme can save space, is convenient for carry out structural design, especially has good result of use bearing not too big occasion.

According to another embodiment of the present invention, the abutting portion has an abutting plane formed to protrude toward the outer peripheral surface of the inner race of the torsion spring, the stopper portion has a stopper plane engaged with the plane, and the abutting plane and the stopper plane are in surface-to-surface abutting engagement.

Plane (inclined plane) structural style between butt joint portion and the backstop portion in this scheme can effectively improve the intensity of butt to can bear great load, be particularly useful for in the mechanical structure that needs carry out the heavy load.

According to another specific embodiment of the invention, the abutting part is provided with a first groove which is communicated or not communicated with the gap between the outer ring of the torsion spring and the inner ring of the torsion spring; the stopping part is provided with a second groove, and the second groove is communicated or not communicated with the gap between the outer ring of the torsion spring and the inner ring of the torsion spring.

according to another embodiment of the invention, the inner circumferential surface of the inner ring of the torsion spring and the outer circumferential surface of the outer ring of the torsion spring are both provided with connecting key grooves.

the invention has the following beneficial effects:

1. The torsion spring elastic body uses a plane spiral line, and the parameterization design can be conveniently carried out by changing the pitch and the number of turns of the spiral line, so that the form of the torsion spring elastic body is convenient to determine, and the elastic body has better parameter performance;

2. The maximum rotation angle of the planar torsion spring is limited by the relative position between the abutting part and the stopping part, and the planar torsion spring has the functions of limiting and protecting the torsion spring structure, and has the advantages of stable structure and high reliability;

3. According to the structural form of the torsion spring elastomer, the overall rigidity of the planar torsion spring is approximately kept unchanged when the inner ring and the outer ring of the torsion spring rotate relatively, so that the torque of a joint can be conveniently acquired, and the cost is greatly reduced;

4. The planar torsion spring has the advantages that the structural form design is more reasonable, the deformation space of the torsion spring elastomer during unidirectional deformation is increased, the torque bearing capacity of the torsion spring is higher, and the maximum relative rotation range is larger.

the present invention will be described in further detail with reference to the accompanying drawings.

drawings

FIG. 1 is a schematic view of the overall structure of the unidirectional planar torsion spring of the present invention;

FIG. 2 is a schematic structural view of the one-way planar torsion spring of the present invention;

FIG. 3 is a graph of stiffness change of the unidirectional planar torsion spring of the present invention;

FIG. 4 is a schematic view of the unidirectional planar torsion spring according to the present invention, wherein the elastic body of the torsion spring is elastically deformed;

fig. 5 is a schematic structural view of a comparative example.

Detailed Description