RU2490528C2 - Combined damped spring shock absorber with movement restriction - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: shock absorber includes a single-turn compression spring, a single-turn tension spring, a bar, a support plate, upper and lower plates rigidly fixed on a bar, radial and axial dampers that restrict movement, nuts, patches that fix ends of springs, a rack and bolts. Compression spring is wound with a pitch that is bigger than design one by the value of deformation under nominal load, and tension spring is wound with a pitch that is smaller by the corresponding value. Damping tin-lead coating is applied to springs.

EFFECT: improving attachment reliability of equipment to foundation, providing possible operation of a shock absorber in wide temperature range and corrosive media.

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Description

The proposed device relates to the field of motion mechanics and can be used for elastic fastening of equipment, devices on ships, as well as in other branches of technology, where there are increased requirements for vibration and shockproof protection of equipment from external vibrations and shocks with limited displacement of the equipment relative to the foundation structures as well as non-proliferation of the equipment’s own sound vibrations to the foundation.

Currently, in the shock-absorbing fastenings of the main and main auxiliary ship power plants, shock-absorbing structures with rubber-cord shells (RKO) are widely used [5].

The growing demands on the reliability and durability of marine power plants (including shock-absorbing structures) lead to the search for new types of shock-absorbing structures.

Known spring vibration isolator with a damping element [6], containing a spiral cylindrical spring, a damping element of a steel rope, wound in a spiral on the wire of this spring, an additional damping element of a steel rope and means for terminating the damping element. An additional damping element made in the form of a shell of the main element is used in the design of the vibration isolator, which is aimed at increasing the damping coefficient of the vibration isolator. The main disadvantage of these vibration isolators is the lack of protection against equipment breakdown, as well as the large required diameter of the spring wire with significant weight and size parameters of the equipment.

Closest to the proposed shock absorber, spring damped combined (APDK) is a prefabricated rubber-metal shock absorber with an axial limiter ARMOO [2], which does not provide a low resonant frequency of the equipment on them, which is important for fastening low-speed main and main auxiliary ship power plants. In addition, the disadvantage of a rubber-metal shock absorber is the dependence of the elastic characteristics on the temperature and composition of the surrounding air.

The proposed design of the APDK shock absorber allows for reliable elastic fastening of ship power plants in the temperature range from minus 50 to plus 100 ° C, as well as in vapors and with direct contact with all types of fuel, oils, sodium chloride, a mixture of isooctane and toluene, in conditions of radioactive and ultraviolet radiation.

The proposed shock absorber provides protection of the equipment from disruption and is able to withstand without a loss of operability short-term, caused by the action of shock shock, five-fold shock deformation by the amount of free play.

In FIG. The design of the APDK shock absorber is presented.

The shock absorber consists of a support plate 10, upper 3 and lower 11 plates, a compression spring 6, a tension spring 9, a rack 13, an axial damper-limiter 12, a radial damper-limiter 8, a radial damper-limiter 14, a rod 7, plates 4, bolts 5, nuts 1 and 15.

The APDK shock absorber can be attached to the foundation 16 via brackets, or the base plate is attached to the foundation, having a recess for the lower part of the shock absorber, directly. The paw of the equipment 2 is attached to the shock absorber rod with a nut 1.

Compression and tension springs differ in winding pitch. The compression spring has a step greater by the amount of deformation under the nominal load, and the tension spring has a step smaller by the same amount than the calculated one, as a result of which the spring step is leveled under the load, and the free movement of the equipment up and down along the 0Z axis becomes equal. In this case, the tangential stress will not be exceeded, since the springs are designed for loads 2.5-3 times higher than the nominal ones.

An important advantage of the APDK shock absorber over the well-known [1], [6] is the redistribution of stresses on both springs simultaneously in all directions of the acting forces, as a result of which the springs are made of wire of a smaller diameter compared to spring shock absorbers, in which the springs work only for compression, or tensile at the same load.

Since compression and tension springs operate in different loading modes, their resonant frequencies do not completely coincide, due to which the dynamic coefficient decreases, and the damping coefficient increases to values from 0.05 to 0.07.

To increase the damping coefficient, a tin-lead coating is applied to the springs, the thickness of which provides a damping coefficient from 0.1 to 0.25. The peculiarity of the tin-lead coating is that the dependence of the inelastic resistance on the amplitude of deformation of the springs is not noticed, while the coating with polymeric materials is ineffective for small deformations [1], [3], [4].

The shock absorber equipment and springs are protected from destruction and disruption from the foundation, both axially and radially, due to the presence of the rod and plates, as well as damping travel stops made of pressed springs wound from stainless steel wire.

Literature

1. Vibration isolator VI. Technical conditions VK. 30424200TU.

2. Combined rubber-metal shock absorber with axial limiter ARMOO. RF patent for invention No. 2358167 IPC F16F 7/00, F16F 13/04, B63H 21/30, BIPM No. 16, 06/10/2009.

3. Reference on the dynamics of structures. Ed. prof. B.G. Koreneva and I.M. Rabinovich. - M .: Stroyizdat. - 1974

4. V.M. Chernyshev. Damping of vibrations of mechanical systems with coatings of polymer materials. M .: Science. - 2004

5. Protective equipment in mechanical engineering. Calculation and design. The reference book under the general ed. S.V. Belova. Moscow. "Engineering". - 1989 g

6. Spring vibration isolator with damping element. RF patent for invention No. 2370687, IPC F16F 7/14, BIPM No. 29, 10/20/2009

Claims (1)

A shock absorber spring damped combined with a stroke restriction, comprising a single-coil compression spring, a single-coil tensile spring, a rod, a support plate, upper and lower plates, rigidly fixed to the rod, radial and axial dampers-travel stops, nuts, plates, securing the ends of the springs, a rack, bolts, characterized in that the compression spring is wound in increments greater than the design value by the amount of deformation under the rated load, and the tension spring is wound in increments of less than the corresponding value Inu, while the damping tin-lead coating is applied to the springs.

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