SU754598A1 - Magnetic end-face clutch - Google Patents

Description

The invention relates to the field of electrical engineering, namely to magnetic couplings, and can be used, for example, in centrifugal pumps, i.e. in mechanisms, where pressure on the sealing wall separating the two cavities occurs at the moment when the mechanism is activated.

A magnetic coupling is known for transmitting rotation through a non-magnetic partition containing a master and a driven coupling half, equipped with permanent magnets [Ϊ].

A disadvantage of the known coupling is that in order to provide the necessary pressure drop between the cavities, the sealing non-magnetic partition must be of sufficient thickness that

reduces clutch torque.

Also known magnetic face clutch to transfer rotation of. one sealed cavity to another, for example for centrifugal pumps, 25 comprising a housing and a leading and driven half-coupling separated by a non-magnetic partition [2].

However, this coupling has not enough moment.

2

The aim of the invention is to increase the transmitted torque

This is achieved by the fact that screw grooves and protrusions are made on the housing surfaces facing one another and one of the coupling halves.

The drawing shows a magnetic coupling for transmitting rotation through a sealed septum in a volume filled with liquid.

The magnetic coupling consists of a leading 1 and a slave 2 coupling halves, separated by a sealed (non-magnetic septum 3. Each coupling half contains permanent magnets 4 and magnetic conductors 5. The partition is rigidly clamped in housing 6. Driven half coupling and housing contain helical grooves 7 and projections 8.

The clutch works as follows.

Each half coupling contains a constant. The alternating polarity magnets 4, having the form of a ring sector. The magnetic fluxes created by the leading magnets 1 and the driven 2 half couplings interact through the nonmagnetic hermetic partition 3 with each other. On the outside of the coupling half the magnetic fluxes are concentrated in mag3

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four

nitrovodov 5. When rotating the leading '

the coupling half is driven into rotation by the driven half coupling, which is in volume

filled with fluid under pressure.

Spiral grooves 7 and protrusions 8 are made on the outer diameter of the driven half-coupling. Similar grooves and protrusions, but in the opposite direction, are made on the inner diameter of the fixed housing. Thus, the design is a slot with multiple threads on the driven coupling half and similar cutting on the body, which makes it possible to create in the process of working the back pressure in the axial direction. This is due to the transfer of energy from the driven half-coupling to the surrounding fluid as a result of the continuous occurrence, development and separation of the vortices on the cutting protrusions.

The mechanism of energy transfer is similar to the mechanism of turbulent friction; therefore, the back pressure increases with increasing intensity of vyhreobrazovaniya. This is facilitated by the presence of helical grooves 7 and protrusions 8 of the opposite direction on the fixed housing 6.

The shape of the protrusions 8 can be trapezoidal, triangular or rectangular. The magnitude of the back pressure depends on the rotational speed, the number of cutting approaches, the length and diameter of the cutting, the radial clearance between the half coupling and the casing, the angle of inclination of the cutting, and its depth.

By creating a backpressure in the gap between the driven half coupling 2 and the housing 6, it is possible to significantly reduce or completely eliminate the fluid pressure on the partition 3 separating the coupling half. This makes it possible to apply a partition 3 of small thickness from the recommended materials with high specific resistance to current (to the top <steel, titanium). The small thickness of the partition 3 on the one hand reduces the loss of the transmitted moment by reducing the magnitude of parasitic currents in the partition, on the other hand increases the transmitted moment due to the possibility of reducing the gap between the coupling halves. In addition, there is a real opportunity to apply non-metallic material (glass, textolite) to the partition. Non-metallic material completely eliminates losses in the partition, which is especially important for high-speed drive and for magnetic couplings with a large number of poles

Such a design can be applied to the drive of a hermetic pump when the pressure created on the pump and the backpressure in the gap appear simultaneously.

It is not excluded the use of such a design to create a back pressure in a gaseous environment.

Creating a back pressure and a gap between the coupling half and the housing makes it possible to reduce the pressure from the medium on the partition separating the drive and driven coupling halves. This allows the use of a wall of small thickness and reduce the gap between the coupling halves, which contributes to an increase in the transmitted torque while reducing the size and simplifying the design of the magnetic coupling.

Claims (1)

Claim Magnetic end coupling for transmitting rotation of a single sealed cavity to another, for example for centrifugal pumps, comprising a housing and a leading and driven coupling half separated by a non-magnetic partition, characterized in that, in order to increase the transmitted torque, the housing surfaces facing one another and helical grooves and protrusions are made of the half coupling.