RU2842476C1 - Linear discrete electric drive - Google Patents

Abstract

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and can be used in electromechanical drive devices for linear discrete displacements. Linear discrete electric drive comprises a magnetic conductor with poles, a traction coil, a movable multisection armature with a composite rod in the form of coaxially located tubular elements, each of which is connected to one of the armature sections and is equipped with a stop at the opposite end. Traction coil is made in the form of separate sections according to the number of armature sections, separated from each other by poles adjacent to magnetic conductor. Beginnings and ends of the leads of each section of the coil are connected to switching means of their supply circuits.

EFFECT: increased initial pulling force, reduced weight of movable elements of the structure and increased efficiency of linear discrete electric drive with preservation of possibility of accurate positioning and fixation of actuating elements within the whole range of motion at discrete movements of anchor sections.

1 cl, 1 dwg

Description

The invention relates to electrical engineering and can be used in electromechanical drive devices for linear discrete movements with the possibility of intermediate fixation of actuators.

A linear stepper electric motor is known, used in a discrete electric drive [auth. 985893 USSR, MKl. H02K 41/03. Linear stepper electric motor // S.V. Savin, N.M. Frolov, A.O. Degtyar, I.I. Ivanov. - No. 33096664/24-07; declared. 29.06.81; published. 30.12.82, bulletin. No. 48. - 3 p.], comprising a housing with electromagnets placed inside with the possibility of axial movement, connected to each other by ties in the form of brackets, and a spring-loaded rod installed with them on the same axis.

Turning on or off any of the electromagnets results in the rod moving the same distance, typical for a linear discrete electric drive, ensuring high positioning accuracy and the possibility of intermediate fixation of actuators in a wide range of movements.

The disadvantages of the known technical solution include the low speed of the device, caused by a significant increase in the mass of the moving parts during discrete movements of the rod, since the inclusion of any of the electromagnets leads to the addition of an additional mass of previously included electromagnets or electromagnets awaiting their inclusion to the moving mass of the rod.

A linear discrete electric drive is known [a.s. 1605297 USSR, MKl. H02K 41/03, F15B 9/09. Linear discrete electric drive // V.I. Doroshchenko, B.N. Zekhtser, E.G. Molchanovsky, B.A. Trostanovsky, Ya.L. Khesin, A.N. Yavor. - No. 40696851/24-07; declared 09.04.86; published 07.11.90, bulletin. No. 41. - 3 p.], containing electromagnets arranged along one axis and articulated in pairs, the outermost of which is made with a flat anchor with a rod fixed to it, and the anchor of each other is an electromagnet located close to it, the mutual movement of which is limited by travel limiters and elastic radial stops alternating along the axis.

High accuracy of positioning of the electric drive rod and the possibility of intermediate fixation of actuators during discrete movements over the entire range of movement is ensured by the mutual movement of electromagnets due to the switching on or off of adjacent electromagnets connected to them through travel limiters.

The disadvantages of the known technical solution include the low speed of the device, caused by the increase in the mass of moving parts during operation, since the mass of the anchor of the electromagnet included in the operation is the mass of previously worked electromagnets or electromagnets waiting to be included, attached to the rod, attracted to each other.

The closest in technical essence to the proposed invention is an electromagnetic motor [a.s. 1721739 A1 USSR, MKl H02K 33/12. Electromagnetic reciprocating motor // A.N. Ryashentsev, V.I. Malinin, A.I. Tolstik. - No. 4738945/07; declared. 20.09.89; published. 23.03.92, bulletin No. 11. - 2 p.], containing a magnetic circuit with poles and a traction coil, a movable multi-section anchor with a composite rod in the form of coaxially located tubular elements, each of which is connected to one of the anchor sections and is provided with a stop at the opposite end.

This technical solution is accepted as a prototype.

However, in such a design of the electromagnetic motor, the increase in the working stroke is associated with an increase in the gaps between individual sections of the anchor, which leads to a decrease in the initial traction force and a decrease in the speed of the device. The initial traction force can be compensated for by increasing the working surface of the anchor sections, and therefore increasing their mass, which also reduces the speed of the device.

Also, the design disadvantages include the possibility of precise positioning of the actuators during the movement of the multi-section anchor only for its two extreme positions, corresponding to the on and off-state of the engine. The design does not provide for intermediate fixation of the actuators during the movement interval of the multi-section anchor.

The problem solved in the proposed invention consists of increasing the speed of a linear discrete electric drive by reducing the mass of the moving elements of the structure while maintaining the functional capabilities of precise positioning and intermediate fixation of the actuators over the range of movement of the anchor.

The solution to the problem is achieved by the fact that a linear discrete electric drive containing a magnetic circuit with poles, a traction coil, a movable multi-section anchor with a composite rod in the form of coaxially arranged tubular elements, each of which is connected to one of the anchor sections and is equipped with a stop at the opposite end, has a traction coil made in the form of separate sections according to the number of anchor sections, separated from each other by poles adjacent to the magnetic circuit, the beginnings and ends of the terminals of each of which are connected to the means for switching their power supply circuits.

Due to such a technical solution, the increase in the working stroke of the multi-section anchor does not affect the initial traction force and does not reduce the speed of the electric drive, which eliminates the disadvantages of the prototype. The mass of the moving parts of the structure depends only on the size of the working stroke and the number of anchor sections used. At the same time, the functional capabilities of the linear discrete electric drive are expanded, determined by the accuracy of its positioning when performing discrete movements on the interval of movement of the multi-section anchor with the possibility of intermediate fixation of the actuators.

The essence of the invention is explained by a drawing, which shows a longitudinal section of a linear discrete electric drive.

The linear discrete electric drive (Fig. 1) contains a magnetic circuit 1 with poles 2 adjacent to it. Between the poles there are sections of traction coils 3 - 6, the terminals of each of which are connected to the switching means 7 of their power supply circuits. Inside the sections of the traction coils and located with them on the same axis, there is a multi-section anchor consisting of movable sections 8 - 11 with a rod 12 and rigidly connected to them tubular elements 13 - 15, equipped with stops at the opposite end and spring-loaded relative to the magnetic circuit by a return spring 16. Separate movable sections of the anchor 8 - 11 form air gaps δ between their working surfaces located perpendicular to their axis, the total length of which is equal to the value of the working stroke of the electric drive. The number of sections of the traction coils is established based on the number of sections of the anchor.

The linear discrete electric drive operates as follows. In the initial state, the sections of the traction coils 3 - 6 are de-energized. Under the action of the elastic force of the return spring 16, the sections of the anchor 8 - 11 and the rod 12 are fixed relative to their working surfaces through the stops, forming air gaps δ between the individual sections, and are in the open state shown in the drawing (Fig. 1)

The operation of the electric drive begins with switching the power supply circuit of the traction coil section 3, located in the lower part of the device. The flow of current in the power supply circuit of the traction coil creates a circuit for closing the magnetic flux Ф, passing through the air gap δ, formed by the lower working surface of the armature section 8. Under the action of the magnetic field, compressing the return spring 16, the armature section 8 moves downwards by the value of the air gap δ, and together with it, due to the interaction of the rod stops 12 and the tubular elements 13 - 15, they move by the value of the working air gap of the armature section 9 - 11, ensuring a downward transmission of force to the armature section 11, to which the load is applied.

Further sequential switching of the power supply circuits of the sections of traction coils 4 - 6 is accompanied by similar processes. In this case, all the higher sections of the anchor 9 -11 are moved by the value of the selected air gap, ensuring the downward transmission of force and discrete movement of the section of the anchor 11 by the value

x = n ⋅δ,

where n is the number of series-connected anchor sections.

The electric drive returns to its initial state under the action of the elastic forces of the return spring 16, constantly applied to the stops of the tubular elements 13 - 14 and the rod 12, and by switching off the power supply circuits of the sections of the traction coils 3 - 6.

In the described operating mode, the sequential disconnection of the power supply circuits of the sections of traction coils 3 - 6 in the reverse order ensures the movement of the armature section 11 upward by the value of the air gap of the worked sections of the armature with the possibility of intermediate fixation of the actuators over the entire range of movement of the multi-section armature.

The elastic properties of the return spring 16 are determined by calculating the force required to position the anchor sections during the return stroke.

In the proposed design variant of the electric drive, the sequential switching on of the power supply circuits of the traction coil sections leads to the movement of the armature section 11 and the load applied to the section from top to bottom by the magnetic field forces, and the disconnection of the traction coil sections leads to the movement of the armature section 11 by the forces of the return spring 16 from bottom to top by the value of the selected air gap. In this case, the armature section 11 can occupy n -intermediate fixed positions on the movement interval, equal to the number of armature sections.

An increase in the speed of action in the considered design of the electric drive while maintaining the value of the working stroke is achieved by reducing the size of the air gap between the sections of the anchor and increasing the number of these sections and, accordingly, the number of sections of the traction coils.

The operation of a linear discrete electric drive does not exclude the possibility of simultaneous switching of the power supply circuits of all sections of the traction coils, which increases the speed of operation of the device over the entire working stroke.

The maximum stroke of the electric drive will depend on the choice of the size of the air gaps between the working surfaces of the anchor sections and the number of installed sections.

Thus, the proposed technical solution, in comparison with known ones, allows for an increase in the initial traction force at large working strokes, a decrease in the mass of the moving elements of the structure and an increase in the speed of the linear discrete electric drive, while maintaining the functional capabilities of precise positioning during discrete movements of the anchor sections with intermediate fixation of the actuators over the entire range of movement.

Claims (1)

A linear discrete electric drive containing a magnetic circuit with poles, a traction coil, a movable multi-section anchor with a composite rod in the form of coaxially arranged tubular elements, each of which is connected to one of the anchor sections and is provided with a stop at the opposite end, characterized in that the traction coil is made in the form of separate sections according to the number of anchor sections, separated from each other by poles adjacent to the magnetic circuit, the beginnings and ends of the terminals of each of which are connected to the means for switching their power supply circuits.