SU1677553A1 - Vibration table resonator - Google Patents

Abstract

This invention relates to a vibration test technique. The purpose of the invention is to increase the durability of the resonator and the accuracy of reproduction of a given vibration by eliminating friction in the connection of beams. The resonator contains a resonating beam 1 and a device for creating an asymmetry of its oscillation cycle, which includes beam 5, clamped in the middle part and attached to the side edges of the resonating beam 1 in its middle part, and a removable one-sided limiter of the working length of the beam 5 Longitudinal axes of the beams intersect at right angles. The stiffness of the beam 5 is less than the stiffness of the beam 1. The asymmetry of the oscillation cycle of the beam 5 is due to the unequal working length and, consequently, the stiffness of the beam 1 with its alternating bending. 3 il.

Description

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The invention relates to a vibration test technique, in particular, to resonators mounted on a shaker table for obtaining an increased level of vibration, and specifically to such resonators that provide an asymmetric oscillation cycle.

The purpose of the invention is to increase the durability of the resonator and increase the accuracy of reproduction of a given vibration.

The proposed resonator eliminates friction in the connection between the resonant beam and the device beam to create an oscillation cycle asymmetry.

Figure 1 shows a resonator with a partial longitudinal section, a general view; figure 2 is the same, top view; on fig.Z - section aa in figure 1.

The resonator contains a resonating beam 1, made with a central protrusion 2 for mounting the test product (not shown) and supporting elements 3 at the ends, serving to install it on the shaker table and having 4 holes for bolts, and a device for creating an oscillation cycle of the oscillating resonant beam 1 This device includes a beam 5 with a stiffness less than that of the resonating beam 1 and a removable one-sided stop 6 of the working length of the beam 5. Beams 1 and 5 are arranged so that their longitudinal axes intersect at right angles, and oskosti bending them pass through the axis of vibration. The beam 5 in the middle part is clamped, and its ends are fastened with screws 7 to the lateral edges of the resonating beam 1 in the middle part of the latter. Pinching beam 5 can be carried out using a bolt 8, screwed into the base 9 of the resonator. For convenience of assembling the device, a hole 10 is made in the center of the resonating beam, and a slot 11 is made in the restrictor b, which is installed between the beam 5 and the base 9.

The resonator works as follows.

When the vibration frequency of the vibrating table table is equal to the natural frequency of the flexural vibrations of the beam 1, the resonant bending vibrations of the latter are excited, while the resonant beam moves the ends of the beam 5 attached to it, which causes its cyclic bending.

When moving the resonating beam 1 upward, the beam 5 bends along its entire length (except for the pinch point), and when moving the resonating beam 1 downwards

Only sections of beam 5 from its ends to limiter 6 are bent. Thus, beam 5 has a variable working length, and hence stiffness, and therefore creates different resistance when the resonating beam moves up and down. As a result, the oscillation amplitudes of the resonating beam 1 in the adjacent half cycles will be different. The cycle asymmetry coefficient rj is determined by the ratio

h - (±) 3

where I is the length of the beam 5;

b - the length of the limiter 6;

and - the length of the clamping of the beam. In the described construction of the resonator, friction in the connection of the beams is practically excluded. Thanks to that rises

durability of the resonator. In addition, the elimination of friction and the gap between them caused by wear of the beams contributes to an increase in the accuracy of reproduction of a given vibration.

Claims (1)

The claims of the resonator for a vibrostand, comprising a resonating beam, made with supporting elements at its ends, serving to install it on the vibrating table, and a device for creating an asymmetry of the oscillation cycle of the resonating beam, including a beam connected with the middle part of the resonating beam along the side The granus of the latter, which differs in that, in order to increase its durability and accuracy of reproduction of a given vibration by eliminating friction in joining beams, creating asymmetry of the oscillation cycle is provided with a removable one-sided limiter of the working length of its beam, the longitudinal axes of the beams intersect at right angles, the beam of this device is clamped in the middle part, its ends are attached to the side edges of the resonating beam, and its rigidity is less than the rigidity of the resonating beam.