CN2215046Y - Pneumatic change valve with bush - Google Patents

Abstract

The utility model relates to a bush type pneumatic change valve, comprising a valve body 2, a valve core 3 the check rings 1 and 5 of both ends of the valve body. The bush type pneumatic change valve is characterized in that a bush 4 is arranged between the valve body 2 and the valve core 3, and a sealing surface 6 is arranged between the external surface of the bush 4 and the valve body 2. A slide gap matching surface 7 is arranged between the internal surface and the valve core 3, and one end of the bush 4 is positioned by the check ring 1. The other end of the bush forms the change chambers K1 and K2 of the change valve by matching the big end of the valve core 3. The bush type pneumatic change valve has the advantages that the bush exists and reduces machining precision. Meanwhile, the change sealing reliability is increased, and the bush type pneumatic change valve has small abrasion and long service life.

Description

Pneumatic change valve with bush

The utility model belongs to pneumatic control components, particularly as the selector valve of pneumatic control components.

Pneumatic reversing slide valve in prior art, dividing from seal form has two kinds of hard sealing (metal to metal) and soft sealings (metal pair is nonmetal).The hard sealing has characteristic of simple structure, but accuracy of manufacturing is had relatively high expectations processing difficulties, the shortcoming that leakage rate is bigger.Soft sealing Sealing is more, and structure is complicated, and its common characteristic is to use the life-span only between about 200～5,000,000 times.This parameter can not satisfy the needs of present engineering.

The purpose of this utility model is in order to improve the deficiency of above-mentioned prior art, to design a kind of air operated reversing valve with lining.

The purpose of this utility model is achieved in that the lining that has a metal in valve body, and a spool is housed in the lining.Be the hard sealing surface of metal to metal between the outer surface of lining and the endoporus of valve body, promptly fitting surface is the hard sealing.Between the internal surface of lining and the spool be slide, by the internal surface Elastic Contact of nonmetallic elastic seal ring and spool, be the matching surface of elastic packing, promptly fitting surface be metal and nonmetal between soft sealing.One end of lining is located by back-up ring, and the big end of spool cooperates with the other end of lining, forms the pressure difference commutation chamber that two different chamber K1 of cross-sectional sizes and K2 can constitute selector valve in a side of valve, is again the positioning device of spool simultaneously.

The utility model has the advantages that the inner and outer surface of lining constitutes two different sealing surfaces, the bore area of its outer surface and valve body constitutes the hard sealing surface, fills the gap with sealer, and its machining accuracy can be lower; Inner chamber and valve core chamber are soft sealings, flexible seal ring and seal ring support slot on the spool, and seal ring is in free state basically, and by the elastic packing of self, it is little to wear and tear, and working life is longer, reaches as high as 2000～3,000 ten thousand times.

The following drawings explanation, accompanying drawing one is a structure sectional view of the present utility model, figure two is the I enlarged views among the figure one.The sequence number of each part in the accompanying drawings is: 1 and 5 is back-up rings, 2 valve bodies, 3 spools, 4 linings, 6 hard sealing surfaces, 7 soft sealing faces, 8 elastic seal rings, 9 support slots, 10 annular grooves, 11 apertures.01, A, P, B, the 02nd, the path of control, K1 and K2 are the commutation chambeies, e is a distance between path.

Below in conjunction with the embodiment in the accompanying drawing, describe the utility model in detail.Accompanying drawing one is the embodiment of one two five-way double air controlled air operated reversing valves.Have two back-up rings 1 and 5 on the valve body 2, in lining 4 is arranged, spool 3 is as basic component, valve body 2 connects outside gas circuit.Have the some apertures 11 of the diameter of annular groove 10 on its annular groove circumference on the lining 4 less than the seal ring diameter of section.Support slot 9 is arranged on the spool 3, seal ring 8 is housed in this groove.Seal ring 8 is separated into some sections with the path on the lining, and spool 3 has only two during work, promptly left stop and right stop.Each position makes path 01, A, and P, B, 02 forms different combinations, realizes the direction control of gas circuit.Seal ring 8 in the support slot 9 on the spool 3 is about free state basically, leans on the elasticity of self to contact with lining 4 inwalls, and its radial pressure is minimum.During motion, the only spool of a sealing side opposite and the gap between the lining with moving direction, sealing reliably, in let out for a short time, it is also little to wear and tear.Aperture 11 on the annular groove circumference of lining outside has reduced the width of block channels, and (being the diameter of aperture) like this, also just reduced the stroke of commutation, makes to reduce about 20～30% apart from e between path.The big end of spool 3 and the end face of lining constitute two commutation chamber K1 and K2 that vary in size.As shown in drawings, the pressure difference of K1 and K2 commutation chamber can also reduce the axial dimension of selector valve simultaneously in the same side of valve, and this big end is the positioning device of spool again, and is simple and reasonable.

Claims (1)

1, a kind of bush type air operated reversing valve, this valve comprises valve body 2, the back-up ring 1 and 5 at spool 3 and valve body two ends, it is characterized in that a lining 4 is arranged between valve body 2 and the spool 3, be sealing surface 6 between the outer surface of lining 4 and the valve body 2, and be the Spielpassung surface 7 of sliding between its internal surface and the spool 3, an end of lining 4 is by back-up ring 1 location, and the other end is by cooperating commutation chamber K1 and the K2 that constitutes selector valve with the big end of spool 3.

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