Valve, in particular for compressors

Abstract

Valve, in particular for compressors, comprising a seat (1) provided with at least one flow way (111), an obturator member (4) able to obstruct said flow way (111) and movable with respect to said seat in a given direction, and means (5) for resiliently stressing said obturator (4), which are able to force said obturator (4) into a given position and are active in the direction of movement thereof; said resilient stressing means (5) comprise at least one cylindrical helical compression spring (5), characterized by the presence, between all the turns and along the entire working length of the spring (5), of inter-turn apertures.

Description

BACKGROUND AND SUMMARY OF THE INVENTION[0001]The present invention relates to a valve, and in particular relates to a valve for reciprocating compressors of the reciprocating type.[0002]The valves of the type currently used in said compressors are normally automatic valves, comprising a valve body, called the seat, consisting of a plate having, formed therein, a plurality of axial flow channels which may be concentric or non-concentric. The opening and closing of said channels is performed by the obturator, a member which may consist of a plurality of elements or a single element. In all cases the obturators are subject to the action of resilient stressing means, typically metal, cylindrical helical, compression springs. The springs are housed inside a valve body (called “counter-seat”) consisting of a plate in which the flow through channels are formed. The abovementioned spring housings may also contain spring protection elements which are preferably made of thermoplastic material...

AI Technical Summary

Benefits of technology

[0003]Most of the said springs are of the compression type with a cylindrical helix or conical helix. Said springs, which are made of steel wire, are formed by a total number of turns, equivalent to the sum of the active turns and the non-active turns. The non-active turns are in contact with the adjacent turns and moreover said turns are suitably ground at the ends to ensure a good axial stability of the said spring.

[0005]A) wear between the external surface of the spring and the surface of the housing cavity, which is eliminated by the introduction of plastic elements which are inserted between the spring and the housing;

[0006]B) wear between the bottom end of the spring and the housing cavity support surface, which is eliminated by the introduction of plastic elements;

[0007]C) wear between the top end of the spring and the surface of contact with the obturator, which is eliminated by the introduction of plastic elements or by the introduction of plastic obturators.

[0009]The object of the present invention is therefore to provide a valve for compressors, in which the wear characteristics of the springs are optimized compared to that known in the state of the art, ensuring a greater working life of the compressor.

Problems solved by technology

The springs constitute one of the most critical parts of the valve; in fact, the high opening / closing frequencies produce, on them and on the parts in contact with them, wear of varying nature and varying degrees.

Despite these improvements, the spring continues to be one of the most critical parts of the valve and the cause of malfunctions.

The development of increasingly faster compressors and the continuous efforts to eliminate the oil in the compressed gas have resulted in an increase in the problems of reliability of the abovementioned components.

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