SU1191651A1 - Elastic element - Google Patents

Abstract

ELASTIC ELEMENT, containing two chambers with variable volume, at least one of which is made in the form of a bellows with covers, interconnected by a channel, and a pressure regulator, characterized in that, in order to simplify the design and reduce stiffness, the pressure regulator is made in the form of an elastic element with zero stiffness, which is a liquid-filled additional bellows with a lid connected by a rigid bond to the bellows lid. with S (L // s: I-T /// /////; about O5 ate - M / S 7

Description

The invention relates to mechanical engineering, namely to elastic elements, and can be used in various vibration protection systems and suspension systems of machines on stands for dynamic tests.

The purpose of the invention is to simplify the design and reduce stiffness.

The drawing schematically shows the proposed elastic element.

The elastic element comprises a chamber 1 with a variable volume, hermetically sealed with a cover 2, which is designed to absorb the external load F, a bellows 3 with a cover 4, a channel 5 communicating the cavity 6 of the chamber 1 with a cavity 7 of the bellows 3, and a pressure regulator made in the form an elastic element with zero rigidity, which is an additional bellows 9 filled with liquid 8 with a cover 10 connected rigidly to the cover 4 of the bellows 3. An adjustable device 11 for fine tuning can be installed on the cover 10 of the additional bellows 9 and an elastic element to the perception of a specific value of the external force F. Channel 12 with an adjustable locking element 13 serves to inlet and exhaust air from the cavity of the additional bellows 9, and channel 14 with the locking element 15 serves to fill and drain the liquid 8. Filling the cavity of the additional bellows 9 liquid 8 must be produced in the absence of the influence of any force F on the cover 2 of the chamber 1 with a variable volume, i.e., when it is unloaded. Cavities 6 and 7 and channel 5 are filled with air at atmospheric pressure, and can be filled with liquid.

The effective area S2 of the additional bellows 9 and the effective area Si of the bellows 3 are selected from the condition

PlSl = P _a S2, where Pi is the gas pressure in the cavity 6 of the chamber 1 with a variable volume;

- effective area of additional bellows 7;

P _a - environmental pressure;

- effective area of the additional bellows 9.

If the external force F, perceived by the additional bellows 9 (by compressing the force F of the air in the chamber 1 with a variable volume of the channel 5 and the bellows 3) is small, to adjust the elastic element, a regulating device 11 is sufficient, which is adjusted to the required constant value of the perceived force F As a control device 11, for example, a load, a spring, etc. can be used.

The elastic element works as follows.

The case is considered when the force F changes according to a harmonic law. In this case ₅ (under the influence of a changing external force F), the cover 2 oscillates, and the chamber 1 with a variable volume is compressed and expanded. The force of the weight of the load is balanced by the pressure Pi of air on the cover 2. In the process ^{, 0} vibrational deformations of the chamber 1 with a variable volume, the volume of its internal cavity 6 changes, i.e., decreases and increases with the frequency of change of the external force F. When the volume of the cavity decreases 6 _{) 5} . (force F increased) air from this cavity flows through channel 5, which causes an increase in air pressure in the cavity 7 of the bellows 3. Since the pressure force P | air in the cavity 7 on the cover 4 overcomes the pressure force P _{and the} surrounding atmosphere on the 20 covers 4 and 10 of the bellows 3 and 9 and acting on the covers 4 and 10 the force of the regulating device 11, it stretches (lengthens) the bellows 3 and 9. This is due to that the atmospheric pressure forces P _o acting on the covers 4 and 10 of the bellows 3 and 9, and ^{25 the} force of the regulating device 1 1 are equal in total to the average gas pressure force Pi on the cover 4.

The movement of the cover 4 of the bellows 3 is associated with the movement of the cover 2 of the chamber 1, with a variable volume ratio ^U S ₃ h ₃ = S _l h ₁ , where S3 is the effective area of the chamber 1 with a variable volume;

From - the amount of movement of the cover 2;

Si is the effective area of the bellows 3; ₃₅ hi - the amount of movement of the cover 4.

As a result, the total volume of the chamber 1 with a variable volume and the bellows 3 remains constant, therefore, the pressure in their cavities 6 and 7 does not increase.

With a decrease in the external force F acting on the cover 2, the opposite happens — the volume of the chamber 1 with a variable volume increases (since the force P | S | now exceeds the value of the external force F), and the volume of the bellows 3 decreases (since a small decrease in pressure Pi violates the equality of ⁵ pressure forces acting on the caps 4 and 10, which causes the compression of the bellows 3 by atmospheric pressure P _a on the caps 4 and 10.

As a result, with oscillatory changes in the volume of the internal cavity 6 of the chamber 1 5Q with a variable volume, changes in the volume of the cavity 7. of the bellows 3 are equal in magnitude and opposite in sign, and the total gas volume of these cavities 6 and 7 is constant, and the gas pressure in them is practically does not change.

VNIIIPI Order 7139/33 Branch of the PPP "Patent", g.

Circulation 897 Subscription

Uzhhorod, st. Project, 4

Claims (1)

ELASTIC ELEMENT containing two chambers with variable volume, at least one of which is made in the form of a bellows with covers, interconnected by a channel, and a pressure regulator, characterized in that, in order to simplify the design and reduce stiffness, the pressure regulator is made in the form an elastic element with zero rigidity, which is an additional bellows filled with liquid with a lid connected by a rigid connection to the bellows lid. 1991611 ° “OS / 5