US 5,392,516 A · Method for forming a spool valve sleeve

Abstract

A valve sleeve is made from a tube having smooth inner and outer diametri surfaces by forming a shallow channel on the tube so that a channelled region of the tube is thinner than other regions of the tube. The tube is confined in a sleeve whose inner peripheral surface conforms with the tube's outer diametrical surface, but the sleeve's inner peripheral surface also defines a gap with the channelled region of the tube. Next, the tube is pressurized to deform the channelled region outward into the gap. As a result, there are both a concavity on the inner diametrical surface of the tube and a smoothly surfaced transition between the concavity and the other regions. Finally, the tube is removed from the sleeve and a port aperture is drilled in the radially outer part of the concavity. As an alternate method, a tube of constant tube wall thickness may be placed in an internally channelled confinement and then pressurized so as to distend regions of the tube wall outward. The tube is removed from the sleeve and holes are drilled in the distended regions.

Claims14

Dependent claims

A method to fabricate a valve sleeve, comprising:

providing a tube with a smooth inner peripheral surface;
creating a channel on the tube recessed with respect to an outer peripheral surface of the tube, whereby a channelled region of a tube wall is thinner than other regions of the tube wall;
placing the tube in an exterior sleeve so that the tube's outer peripheral surface at the other regions fits closely with an inner peripheral surface of the sleeve;
pressurizing the tube to plastically deform the channeled region outward, whereby the channelled region forms a concavity in the inner peripheral surface of the tube;
creating an aperture through the concavity.

2 more elements

A method for forming a sleeve of a valve, comprising:

providing a metal tube having smooth inner and outer diametrical surfaces;
forming a cross-sectionally wide, flat channel on the tube recessed with respect to the tube's outer diametrical surface so that a channelled region of the tube is thinner than other regions of the tube;
placing the tube in a confinement sleeve whose inner peripheral surface conforms with the tube's outer diametrical surface, the inner peripheral surface defining a gap with the channelled region of the tube;
pressurizing the tube to deform the channelled region outward into the gap so as to form both a concavity on the inner diametrical surface of the tube and a smoothly surfaced transition between the concavity and the other regions;
removing the tube from the sleeve;
forming a port aperture in an outer part of the concavity.

3 more elements

A method for forming a valve sleeve of a valve, comprising:

providing a metal tube having smooth inner and outer diametrical surfaces;
providing a confinement sleeve whose inner peripheral surface conforms with the tube's outer diametrical surface;
forming a wide, flat channel in the confinement sleeve recessed with respect to the confinement sleeve's inner diametrical surface;
placing the tube in the confinement sleeve, an unsupported region of the tube defining a gap with a channelled region of the confinement sleeve;
pressurizing the tube to plastically deform the unsupported region of the tube radially outward into the gap, such that a concavity on the inner diametrical surface of the tube is formed;
forming a smoothly surfaced transition between the concavity and a neighboring section of the inner diametrical surface;
removing the sleeve from the tube;
placing a port aperture in a radially outer zone of the concavity.

5 more elements

Dependencies are inferred from the claim text.

Method for forming a spool valve sleeve

Life of this patent

Method for forming a spool valve sleeve

Life of this patent

Abstract

Claims14