RU204473U1 - Electromagnetic artificial muscle - Google Patents

Abstract

The utility model relates to controlled drives for converting electrical energy into mechanical energy and can be used in robotics, mechanical engineering and medicine, in particular, in the development of bionic prostheses and exoskeletons. The electromagnetic artificial muscle contains a fixed permanent magnet at the opposite end of the movable chamber. The inner cavity of the movable chamber is filled with a magnetic fluid with the addition of additives to increase the magnetic susceptibility, and the movable chamber is made with the addition of particles capable of magnetizing and attracting magnetic fluid particles to itself, while the movable chamber is enclosed in an outer braid to limit its expansion when compression of an electromagnetic artificial muscle. In the core of the electromagnet and permanent magnet, a blind hole with a cut thread is made to secure the artificial muscle in the structure driven by the machine or mechanism. The technical result of the proposed utility model is to eliminate the shortcomings of the known technical solutions, namely: increasing the developed effort; increased reliability; increase in the working stroke of the muscle. 2 ill.

Description

Technical field to which the utility model belongs

The utility model relates to controlled drives for converting electrical energy into mechanical energy and can be used in robotics, mechanical engineering and medicine, in particular, in the development of bionic prostheses and exoskeletons.

State of the art.

Devices for converting electrical energy into mechanical are known from the prior art, so one of them is proposed in [1] (USSR Patent SU No. 901611 A1, publ. 01/30/1982, "AA Kozlov electrohydraulic drive"), containing cameras with elastic walls filled with a liquid ferromagnet, equipped with electric windings consisting of inductance coils connected in series.

The disadvantages of the known device are:

- insufficient reliability due to the presence of liquid, which, in the event of the formation of cracks in the case, can leak out, and also in the event of failure of one of the chambers, the performance will significantly decrease;

- high energy intensity and low developed effort, because there is no possibility to use it in the construction of chambers with ferrite cores.

- there are no elements in the design of the drive for quick installation of this technical means, which causes difficulties when installing this muscle in any machine or mechanism.

Also known is a device for converting electrical energy into mechanical energy, proposed in [2] (RF Patent No. 2372056 on application 2008104288/14 dated 02/04/2008, IPC A61F 2/50, A61F 2/72, A61F 2/08, B25J 17/02, Publ. 10.11.2009., Bulletin No. 31., Artificial muscle (options)), containing chambers with elastic walls, filled with the possibility of forming pressure on the walls with a substance with ferromagnetic properties and having electrically conductive windings. According to the first embodiment, chambers with elastic walls are toroidal, enclosed in a hollow elastic shell in the form of an elongated ellipsoid, and are located along it. According to the second version, chambers with elastic walls are toroidal and enclosed in at least two elastic shells, enclosed one into the other with a gap between them and having the shape of elongated ellipsoids, while in each of the shells the chambers are located along them.

The disadvantages of this device are:

- the complexity of the design, since it requires special equipment to create toroidal chambers with electric windings, as well as the complexity of repair in case of failure of one of the chambers;

- high energy intensity and low developed effort, because there is no possibility to use chambers with ferrite cores in the construction;

- low reliability and muscle heating during work, because the structure contains contact surfaces.

- small working stroke and, as a consequence, low geometric efficiency;

- in the construction of the muscle there are no elements for quick installation of this technical device, which causes difficulties when installing this muscle in any machine or mechanism.

The closest to the proposed technical solution, taken as a prototype, is the device described in [3] (RF Patent No. 2598763C2 on application 2014113482/14 dated 04.04.2014, IPC A61 2/50, A61F 2/08, B25J 18 / 02, Publ. 09/27/2016, Bulletin No. 28 "Artificial muscle"), containing a movable chamber made in the form of a cylinder, made of an elastic, easily compressible material, in its volume filled with ferromagnetic metal particles of small size, to the end of which ( chamber), a solenoid with a ferrite core (electromagnet) is attached.

The disadvantages of the known technical solution are:

- small working stroke and, as a consequence, low geometric efficiency;

- a low developed force, namely, the guidance of a magnetic field created by one electromagnet on ferromagnetic metal particles, has a low effect on these particles, as a result of which the developed force is reduced;

- low reliability due to high wear of the movable chamber due to the presence of dry friction with ferromagnetic particles;

- disconnection of the muscle in case of failure of the electromagnet.

- in the construction of the muscle there are no elements for the quick installation of this technical means, which causes difficulties when installing this muscle in any machine or mechanism.

Disclosure of the utility model.

The technical results of the proposed utility model are the elimination of the indicated disadvantages, namely:

- increasing the developed effort;

- increased reliability;

- an increase in the working stroke of the muscle.

This is achieved by the fact that, unlike the known technical solution, this electromagnetic artificial muscle contains a fixed permanent magnet at the opposite end of the movable chamber. The inner cavity of the movable chamber is filled with a magnetic fluid with the addition of additives to increase the magnetic susceptibility, and the movable chamber is made with the addition of particles capable of magnetizing and attracting magnetic fluid particles to itself, while the movable chamber is enclosed in an outer braid to limit its expansion when compression of an electromagnetic artificial muscle.

In the core of the electromagnet and permanent magnet, a blind hole with a cut thread is made to secure the artificial muscle in the structure driven by the machine or mechanism.

The essence of the proposed design of the electromagnetic muscle is as follows.

The permanent magnet provides the initial magnetization of the magnetic fluid in the movable chamber, preventing it from flowing out in the event of the formation of various defects in the movable chamber. Also, this permanent magnet provides an increase in the working stroke and reduces the energy intensity of the muscle, because the magnetic field of a permanent magnet, passing through the magnetic fluid and increasing, interacts with the electromagnet even before the current is applied to it, trying to attract it to itself at a considerable distance.

The movable chamber is made with the addition of particles made with the ability to magnetize and attract particles of magnetic fluid to prevent it from flowing out of the chamber when cracks are formed in it. This is achieved by the fact that under the action of a magnetic field generated by a permanent magnet, the particles are magnetized and begin to attract the particles of the magnetic fluid, thereby preventing them from flowing out of the chamber.

One of the ways to implement this chamber is to add ferromagnetic particles to the elastic base (liquid silicone) in the process of forming the movable chamber, while the content of ferromagnetic particles should be at least 50% of the volume of the elastic base. After the mixture has cured, the ferromagnetic particles are uniformly distributed and equidistant from each other throughout the volume of the chamber, and when the chamber is stretched or compressed, the distance between the ferromagnetic particles increases or decreases. The stretching or compression of the chamber is provided by an elastic base (silicone).

The inner cavity of the movable chamber is filled with a magnetic fluid, which eliminates dry friction and enhances the magnetic field passing through it, while an additive is added to the magnetic fluid to increase its magnetic susceptibility and, as a result, increase the developed force of the electromagnetic artificial muscle. The use of magnetic fluid is due to its low density compared to other magnetic materials, which will reduce the weight of the finished product. The additives used are small size magnetically sensitive particles.

The movable chamber is enclosed in an outer braid to limit its expansion when the electromagnetic artificial muscle is compressed. This is necessary to prevent excessive expansion of the movable chamber, which can contribute to the violation of its integrity and the formation of various defects.

In the core of the electromagnet and permanent magnet there is a blind hole with a threaded thread for fixing the electromagnetic artificial muscle in a structure driven by a machine or mechanism, while there is no need to develop fasteners for installing an electromagnetic artificial muscle, which simplifies the process of its installation and design of robotic devices with its application.

Description of drawings.

The features and essence of the claimed utility model are illustrated by drawings. FIG. 1 is a general view of an electromagnetic artificial muscle; in fig. 2 shows an embodiment of an electromagnetic artificial muscle.

Implementation of the utility model.

An electromagnetic artificial muscle (Fig. 1) contains an electromagnet 1 connected to a permanent magnet 2 through a movable chamber 3, the inner cavity of which is filled with a magnetic fluid with the addition of additives 4, and also contains an outer braid 5, a fastening hole 6.

An electromagnetic artificial muscle works as follows.

When an electric current is applied to the electromagnet 1, a magnetic field is generated, which is conducted and amplified, passing through the magnetic fluid with additives 4, interacting with the magnetic field of the permanent magnet 2. As a result, the electromagnet and the permanent magnet are attracted to each other, performing useful work. To ensure the reverse stroke, it is enough to change the direction of the current flow for the electromagnet, as a result, a magnetic field of the same name is generated and the electromagnet with a permanent magnet repel each other.

Several modes of operation of an electromagnetic artificial muscle are possible: pulsed, smooth, high-frequency.

Pulse mode. It is characterized by the supply of a large current to the electromagnet in the form of an impulse, at which a sharp and complete compression of the muscle with high power indicators occurs. In this case, the electromagnet operates in overload mode.

Smooth mode. It is characterized by the supply of current to the electromagnet from zero to the nominal operating one. At the same time, when regulating the current strength, a smooth adjustment of the developed effort of the working stroke of the electromagnetic artificial muscle is provided.

High frequency mode. It is characterized by pulse-width modulation of the supplied current to the electromagnet, while the adjustment of the muscle stroke will depend on the pulse length and frequency of the supplied current. Thus, the work of an electromagnetic artificial muscle in this mode is similar to the work of a human muscle.

Before starting work, the electromagnetic artificial muscle is installed in the mechanism in a neutral position using the fixing hole 6. One end is rigidly fixed to the stationary part of the mechanism, the other end to the moving part in such a way as to neutralize the attraction of the permanent magnet to the electromagnet. After that, the optimal mode of muscle operation is selected based on the requirements for the machine or mechanism.

If necessary, an additional movable chamber filled with magnetic fluid and with a permanent magnet mounted on the opposite side of the electromagnet can be installed (Fig. 2). This will provide an increase in the working stroke, as well as increase the strength characteristics of the muscle, because permanent magnets located at opposite ends of such an assembly will interact with each other and with the electromagnet.

The proposed design of an electromagnetic artificial muscle can be used in robotics, mechanical engineering and medicine, in particular, in the development of bionic prostheses and exoskeletons.

Information sources:

1. SU No. 901611 A1, publ. 01/30/1982, "AA Kozlov electro-hydraulic drive" /;

2. RF patent No. 2372056 on application 2008104288/14 dated 02/04/2008, A61F 2/50, A61F 2/72, A61F 2/08, B25J 17/02, Publ. 10.11.2009., Bul. No. 31., Artificial muscle (options));

3. RF patent No. 2598763C2 on application 2014113482/14 dated 04.04.2014, IPC A61 2/50, A61F 2/08, B25J 18/02, Publ. September 27, 2016, Bul. №28 "Artificial muscle".

Claims (2)

1. An electromagnetic artificial muscle containing a movable chamber made in the form of a cylinder, made of an elastic compressible material, and an electromagnet is attached to the end of the movable chamber, characterized in that a permanent magnet is fixed at the opposite end of the movable chamber, the inner cavity of the movable chamber is filled with a magnetic fluid with adding additives to it to increase the magnetic susceptibility, and the movable chamber is made with the addition of particles made with the ability to magnetize and attract magnetic fluid particles to itself, while the movable chamber is enclosed in an outer braid to limit its expansion during compression of the electromagnetic artificial muscle. 2. An electromagnetic artificial muscle according to claim 1, characterized in that a blind hole with a cut thread is made in the core of the electromagnet and the permanent magnet for fixing the artificial muscle in a structure driven by a machine or mechanism.

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