RU2108170C1 - Adjustable asymmetrical vibration exciter - Google Patents

Abstract

FIELD: mechanical engineering; vibrating transportation devices. SUBSTANCE: vibration exciter is made as planetary self-balancing mechanism with two fixed central wheels, two carries in form of synchronizing gear wheels with unbalance weight secured on each gear wheel, and two unbalanced planetary gear wheels, one per each carrier. Unbalance weight and planetary wheel on each carrier are installed in diametric opposition. Asymmetry of disturbing force is adjusted by changing static moment of synchronizing gear wheels by shifting of unbalance weights in radial direction with subsequent fixing in any point. Central and planetary wheels are of equal diameter. EFFECT: possibility of adjustment of disturbing force without replacement of design members of vibration exciter. 1 dwg

Description

 The invention relates to vibration technology, in particular to a vibratory drive of transport and technological devices.

 Known planetary vibrator (and.with. 400375, B 06 B 1/16) containing a stationary central gear, a carrier and two planetary gears statically balanced relative to the axis of the carrier. One of the planetary wheels is made with an unbalance relative to its own axis. The disturbing force developed by such a vibrator is not asymmetric, since it is a constant module vector with a changing direction.

 The closest set of essential features is a loader self-balancing vibrator (a.s. 471126, B 06 B 1/16), which contains two stationary central gear wheels, two carriers in the form of synchronizing gears and two unbalanced planetary gears - one on each drove. In addition, on each carrier diametrically opposite to the planetary wheels, unbalances are fixed that are superior in weight to the planetary wheels.

 A self-balancing vibrator develops an asymmetric disturbing force, since its vector has a variable module and a strictly defined direction, and the maximum values of the module in different directions of the same direction are not equal to each other. The design of the self-balancing vibrator does not allow changing the asymmetry of the disturbing force without changing the structural elements of the device; therefore, the use of the vibrator is limited to using it in one specific vibration device to perform specific operations.

 The effect of vibrational movement is known in the art, on which the vibrational transportation of individual bodies and bulk materials in vibrating trays, pipes, vessels, the vibrational separation of particles of bulk material by density, size and other parameters is based; movement of vibratory devices. The main principle of the occurrence of the effect of vibrational displacement is the creation of asymmetry of forces in the direction of displacement arising in the process of vibration of vibration devices or their parts. A number of methods are known for creating asymmetries of forces for implementing the process of vibrational displacement.

 The most effective is a method of modulating an asymmetric disturbing force using an asymmetric self-balancing vibration exciter, which does not require additional transducers of vibration processes and the fulfillment of the necessary conditions for the placement of its vibration device. When using transport and technological vibratory machines for working with various materials that differ in size, density, coefficients of internal and external friction, etc. each time you have to change the operating mode of the vibrator.

 The invention is aimed at expanding the scope, simplifying the readjustment of vibration machines by creating asymmetries of moving forces only due to vibration exciter, which has the ability to adjust the asymmetry of the disturbing force.

 In the proposed device, as a controlled asymmetric vibration exciter, it is possible to use a self-balancing vibrator (a. P. 471126), performing fixed unbalances on the carriers with the possibility of moving along the radii of the synchronizing gears with the possibility of fixing in the required position, provided that the central and planetary gears of one diameter.

The perturbing force developed by such a vibration exciter is the resultant of centrifugal forces from the rotation of unbalanced masses around the corresponding axes and karyolis forces from the simultaneous rotation of unbalanced planetary wheels around two axes. All these forces, depending on the periods of their oscillations, can be grouped into two types:
F ₁ = 3ΣM $\genfrac{}{}{0ex}{}{\text{st}}{\text{1}}$ • ω ² • cos2α
F ₂ = ΣM $\genfrac{}{}{0ex}{}{\text{st}}{\text{2}}$ • ω ² • cosα
where M $\genfrac{}{}{0ex}{}{\text{st}}{\text{1}}$ - the sum of the static moments of the unbalanced planetary wheels relative to their own axles;
ω is the carrier speed;
α is the angle of rotation of the fixed unbalances;
M $\genfrac{}{}{0ex}{}{\text{st}}{\text{2}}$ - the sum of the static moments of motionless unbalances and unbalanced planetary wheels relative to the axles of the carrier.

The forces F ₁ and F ₂ make harmonic oscillations along the axis of symmetry of the pathogen with periods respectively π and 2π. The disturbing force of the vibration exciter is the result of the addition of two harmonic forces with different periods, which leads to its asymmetry.

Changing the asymmetry of the perturbing force is quite simple, it is enough to change the sum of the static moments ΣM $\genfrac{}{}{0ex}{}{\text{st}}{\text{2}}$ , relative to the axles drove. This is achieved by moving the stationary unbalances along the radii of the synchronizing gears.

The device allows a fairly wide range of adjustment of the magnitude of the asymmetry of the perturbing force from zero when the planetary wheels are balanced by fixed unbalances relative to the axes of the carrier, to F ₂ when the fixed unbalances are shifted to the centers of the carrier, and the maximum value of the perturbing force when α = 2πn or when the fixed unbalances are shifted to drove to the edges, and the maximum value of the perturbing force at α = πn.

 The drawing shows a plan of an adjustable asymmetric vibration exciter (case conditionally not shown).

 The Central gears 1 are rigidly connected to the fixed axles, on which the carrier 2 are mounted rotatably mounted in the form of synchronizing gears, which are engaged with each other. The planetary unbalanced gears 3 are mounted on the carriers 2 with the possibility of rotation around their axes and are engaged with the central gears 1. Opposite to the planetary gears 3 on the carrier 2 there are unbalances 4. Debalances 4 have the ability to move along the radii of the carrier 2 and can be fixed in any position.

 Vibration exciter works as follows. Imbalances 4 are established and fixed in the required position. A torque is applied to one of the carrier 2. All unbalanced masses come into rotation around the axles of the carrier, and the unbalanced masses of planetary wheels also rotate around their own axes. As a result of the rotation of unbalanced masses, inertial forces arise, whose components in the direction perpendicular to the axis of symmetry of the vibration exciter are mutually balanced due to the synchronism of their rotation. Components of inertial forces parallel to the axis of symmetry of the vibration exciter are summed into the resultant, which is the disturbing force of the vibration exciter, the magnitude and asymmetry of which depend on the place of fixation of unbalances 4 on the carriers 2.

Claims (1)

 An adjustable asymmetric vibration exciter containing two stationary central gear wheels, two carriers in the form of synchronizing gears, two unbalanced planetary gears, one on each carrier, and two fixed unbalances mounted on carriers opposite to planet wheels, characterized in that the unbalances have the ability movements along the radii of synchronizing gears and the possibility of fixation at any point of movement, provided that the central and planetary gears have the same diameter.