Fluid-controlled, in particular hydraulically or pneumatically controllable slide valve arrangement

Claim 2

A fluid-controlled slide valve arrangement, in particular a pneumatically or hydrauliCally controlled slide valve arrangement, for alternately connecting an outflow conduit with a pressure conduit and return flow conduit of a fluid-operating system, comprising a slide valve housing, a sleeve valve member displaceably mounted in said slide valve housing, said sleeve valve member incorporating at one end a piston extension of larger diameter, said larger diameter piston extension possessing opposed end faces, fluid-operated control means for alternately applying a pneumatic or hydraulic control overpressure to said end faces of said piston extension in order to displace said sleeve valve member during the switching operation, said pneumatic or hydraulic control overpressure only being maintained during a portion of the switching operation, relief channel means provided for said valve arrangement, said relief channel means provided for said valve arrangement, said relief channel means communicating with the outside, said control pressure dropping during the latter part of said switching operation as soon as any of said relief channel means are freed by said enlarged piston extension, said slide valve housing incorporating a working portion provided with said outflow conduit, said pressure conduit and return flow conduit, a discharge channel for leakage fluid medium, said slide valve housing being provided with internal groove means communicating in flow relationship with said discharge channel, said internal groove means being disposed between said working portion of said slide valve housing and said larger diameter piston extension.

Claim 3

A fluid-controlled slide valve arrangement, in particular a pneumatically or hydraulically controlled slide valve arrangement, for alternately connecting in flow relationship an outflow conduit with a pressure conduit and return flow conduit for a working fluid medium of a fluid-operating system, comprising a slide valve housing, a sleeve valve member incorporating a sleeve body displaceably mounted in said slide valve housing, said sleeve valve member being devoid of any sealing means between said sleeve body and said slide valve housing to reduce frictional forces therebetween, to thus permit more rapid displacement movements of said sleeve valve member, said sleeve valve member further incorporating at one end a piston extension of larger diameter, said larger diameter piston extension possessing opposed end faces, a fluid-operated control means for alternately applying a pneumatic or hydraulic control overpressure to said end faces of said piston extension in order to selectively displace said sleeve valve member during the switching operation, said pneumatic or hydraulic control overpressure only being maintained during a portion of the switching operation, at least one relief channel means provided for said valve arrangement, said relief channel means communicating with the outside, said control pressure dropping during the latter part of said switching operation as soon as said relief channel means is freed by said enlarged piston extension, said relief channel means, when freed, further serving to vent any leakage working fluid medium which may have seeped between said sleeve body of said sleeve valve member and said slide valve housing into the region of said larger diameter piston extension, to thus prevent said leakage working fluid medium from flowing into said fluid-operated control means and fouling operation thereof.

Claim 4

A fluid-controlled slide valve arrangement, in particular a pneumatically or hydraulically controlled slide valve arrangement, for alternately connecting in flow relationship an outflow conduit with a pressure conduit and return flow conduit for a working fluid medium of a fluid-operating system, comprising a slide valve housing, a sleeve valve member incorporating a sleeve body displaceably mounted in said slide valve housing, said sleeve valve member being devoid of any sealing means between said sleeve body and said slide valve housing to reduce frictional forces therebetween, to thus permit more rapid displacement movements of said sleeve valve member, said sleeve valve member further incorporating at one end a piston extension of larger diameter, said larger diameter piston extension possessing opposed end faces, a fluid-operated control means for alternately applying a pneumatic or hydraulic control overpressure to said end faces of said piston extension in order to selectively displace said sleeve valve member during the switching operation, said pneumatic or hydraulic control overpressure only being maintained during a portion of the switching operation, at least one relief channel means provided for said valve arrangement, said relief channel means communicating with the outside, said control pressure dropping during the latter part of said switching operation as soon as said relief channel means is freed by said enlarged piston extension, said relief channel means, when freed, further serving to vent any leakage working fluid medium which may have seeped between said sleeve body of said sleeve valve member and said slide valve housing into the region of said larger diameter piston extension, to thus prevent said leakage working fluid medium from flowing into said fluid-operated control means and fouling operation thereof.

Claim 5

A fluid-controlled, in particular a pneumatically or hydraulically controllable slide valve arrangement as defined in claim 2, wherein said fluid-operated control means incorporates respective control conduit means for alternate application of said pneumatic or hydraulic control overpressure to the end faces of said piston extension in order to displace the sleeve valve member.

Claim 6

A fluid-controlled slide valve arrangement as defined in claim 2, wherein there are provided two relief channel means each one of which is disposed in operable relationship with respect to each respective end face of saId larger diameter piston extension.

Claim 7

A fluid-controlled slide valve arrangement as defined in claim 2, wherein said sleeve body and said larger diameter piston extension are each internally hollow for the purpose of reducing the weight of said sleeve valve member to permit more rapid displacement thereof.