CZ297963B6 - Servo unit drive employing temperature deformations of metal alloys with retentivity - Google Patents

Abstract

The present invention relates to a drive employing temperature deformation of metal alloys with retentivity to create a continuous rectilinear or rotational motion. The drive is provided with a mechanical output member (1) anchored to operating end (2.1) of a first link (2) and to operating end (3.1) of a second link (3), whereby both the links (2) and (3) are made of metal alloys with retentivity. A reference end (2.2) of the first link (2) is supported by a first movement limiter (6) and a first spring (4). A reference end (3.2) of the second link (3) is supported by a second movement limiter (7) and a second spring (5). Both the first spring (4) and the second spring (5) are anchored in the base of a drive (8).

Description

Servomechanism drive using thermal deformation of shape memory metal alloys

Technical field

The present invention relates to a servo drive in which the thermal deformation of Shape Memory Alloy (SMA) metals is utilized to effect linear or rotational movement of the servo output member.

BACKGROUND OF THE INVENTION

In the prior art servomechanics drives, the movement of the servomechanism output member is realized by using electromagnetic, hydraulic, or pneumatic elements. The disadvantages of such solutions are primarily mechanical friction in moving parts, noise and vibration, which limits their use, for example in micro-systems with a high degree of mobility. Servo drives using thermal deformation of shape memory metal alloys do not have these drawbacks and allow structures with a very high force / weight ratio.

SUMMARY OF THE INVENTION

These drawbacks are eliminated by a servomechanism drive utilizing thermal deformation of the shape memory metal alloys to produce a continuous linear or rotational motion, wherein the output mechanical member is anchored to the working end of the first cell and to the working end of the second cell, made of shape memory metal alloys and the reference end of the first link is supported by the first movement limiter and the first spring, the reference end of the second link is carried by the second movement limiter and the second spring, both the first spring and the second spring being anchored in the drive base.

For driving the servomechanism according to the invention, it is advantageous if the output mechanical member has a continuous linear or rotational movement such that its deviation from the rest position is determined by the difference of the instantaneous length of the first cell and the instantaneous length of the second cell. the instantaneous length of the first spring and the instantaneous length of the second spring are constant over the entire working range of the drive.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be explained in more detail with reference to the drawing, in which schematically an example of a proposed servomechanism drive solution utilizing thermal deformation of shape memory metal alloys to create a continuous linear or rotational motion is illustrated.

DETAILED DESCRIPTION OF THE INVENTION

The drive of the servomechanism utilizing the thermal deformation of the shape memory metal alloys to produce a continuous linear or rotational motion consists of an output mechanical member 1 anchored to the working end 2.1 of the first section 2 and to the working end 3.1 of the second section 3. shape memory metal alloys having the property of mechanical deformation upon temperature change. The drive further comprises two movement limiters 6 and 7 and two springs 4 and 5. The reference end 2.2 of the first link 2 is carried by the first movement limiter 6 and the first spring 4. The reference end 3.2 of the second link 3 is carried by the second movement limiter 7 and the second spring 5 The first spring 4 and the second spring 5 are anchored in the base of the drive 8.

-1 CZ 297963 B6

The output mechanical member 1 can be realized, for example, as a rotating shaft, a two-arm lever or a sliding mechanism, its deviation from the rest position being dependent on the difference of the instantaneous length of the first link 2 and the instantaneous length of the second link. output length L These lengths can be influenced, for example, by the controlled electrical heating of cells 2 and 3.

If, as a result of the force effects caused by the instantaneous temperature of the links 2 and 3 and the application of external forces to the mechanical member 1, the sum of the instantaneous lengths of both links 2 and 3 is less than a certain value given by the servo mechanism design, e.g. 7, the first spring 4 and the second spring 5 are deformed and consequently the force is applied to the first link 2 and the second link 3. Such an arrangement of the servo mechanism according to the invention prevents excessive forces on the links 2 and 3 and consequently with a shape memory from which the cells 2 and 3 are made.

In the drive of the servo mechanism according to the invention, it is advantageous to have such a configuration that, over the entire operating range of the drive, the sum of the instantaneous length of the first link 2 is the instantaneous length of the second link 3 and the instantaneous length of the first spring 4 and the instantaneous length of the second spring 5.

An example of a particular embodiment of a servomechanism drive according to the invention may be the articulated mechanism of a working arm of a robot, the rotational part of which is subjected to the torque of a pair of forces formed by two shape memory metal alloys.

Industrial applicability

It is advantageous to use the actuator drive according to the invention for the construction of continuous mechanical drives, in particular micro-robots and micro-manipulators. The advantage over electromagnetic drives is not only the absence of friction surfaces, but also the scattering magnetic field. Another advantage over hydraulic and pneumatic drives is the absence of a source of working medium such as pressure oil or air.

Claims (2)

PATENT CLAIMS A servomechanism drive employing thermal deformation of shape memory metal alloys to produce a continuous linear or rotational motion, characterized in that the output mechanical member (1) is anchored to the working end (2.1) of the first member (2) and to the working end (1). 3.1) of the second link (3), both links (2) and (3) are made of shape memory metal alloys and the reference end (2.2) of the first link (2) is supported by the first movement limiter (6) and the first spring (4) 1), the reference end (3.2) of the second link (3) is supported by the second movement limiter (7) and the second spring (5), the first spring (4) and the second spring (5) being anchored in the base of the drive (8). A servo drive according to claim 1, characterized in that the output mechanical member (1) has a continuous linear or rotational movement such that its deviation from the rest position is determined by the difference between the instantaneous length of the first link (2) and the instantaneous length of the second link (1). 3), wherein the sum of the instantaneous length of the first link (2), the instantaneous length of the second link (3), the instantaneous length of the first spring (4) and the instantaneous length of the second spring (5) is constant throughout the working range of the drive.