Valve having open-center spool with separated inserts

Patent metadata

Field	Value
Publication number	US-9915355-B2
Application number	US-201514876082-A
Country	US
Kind code	B2
Filing date	Oct 6, 2015
Priority date	Oct 6, 2015
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

A spool assembly is disclosed for use in a valve. The spool assembly may have a cylindrical body with a first end, a second end, and a bore passing from the first end through the second end. The spool assembly may also have a first insert with a first land slidably disposed inside the bore at the first end, and a second insert separate from the first insert. The second insert may have a second land slidably disposed inside the bore at the second end.

First claim

What is claimed is:

1. A spool assembly for a valve, comprising:
a cylindrical body having a first end, a second end, and a bore passing from the first end through the second end;
a first insert having a first land slidably disposed inside the bore at the first end, wherein the first insert further includes a mounting land and a stem connecting the mounting land to the first land;
a second insert separate from the first insert and having a second land slidably disposed inside the bore at the second end; and
a feedback element extending from an axial end of the cylindrical body, wherein the feedback element includes a conical feedback ramp.

2. The spool assembly of claim 1 , further including at least one radially oriented orifice formed within the cylindrical body at a location between the first and second lands.

3. The spool assembly of claim 2 , wherein the at least one radially oriented orifice includes at least a first orifice spaced apart from at least a second orifice.

4. The spool assembly of claim 2 , wherein the first and second lands together at least partially define an open axial space between the first and second inserts, wherein relative movement between the cylindrical body and the first and second inserts shifts a location of the open axial space relative to the at least one radially oriented orifice.

5. The spool assembly of claim 1 , wherein the second insert further includes:
a mounting land; and
a stem connecting the mounting land to the second land.

6. The spool assembly of claim 5 , wherein the stem of the first insert is a different length than the stem of the second insert.

7. The spool assembly of claim 5 , wherein:
the first and second lands have about equal diameters; and
the mounting lands of the first and second inserts have about equal diameters that are larger than the diameters of the first and second lands.

8. The spool assembly of claim 1 , wherein the feedback element has a diameter less than a diameter of the cylindrical body.

9. The spool assembly of claim 1 , wherein the axial end of the cylindrical body is open.

10. The spool assembly of claim 9 , wherein the feedback element is connected to the axial end of the cylindrical body by a plurality of spokes.

11. The spool assembly of claim 1 , wherein the cylindrical body is internally unrestricted between the first and second lands.

12. A valve, comprising:
a block having:
a bore;
a first passage extending to the bore at a first axial location; and
a second passage extending to the bore at a second axial location;

a spool assembly disposed within the bore of the block and having:
a cylindrical body having a first end, a second end, a bore passing from the first end through the second end, a least a first radially oriented orifice that passes through a wall of the cylindrical body to communicate the first passage with the bore, and at least a second radially oriented orifice that passes through the wall of the cylindrical body to communicate the second passage with the bore;
a first insert having a first land slidably disposed inside the bore at the first end; and
a second insert separate from the first insert and having a second land slidably disposed inside the bore at the second end, such that the first and second lands together at least partially define an open axial space between the first and second inserts that includes the at least a first and at least a second radially oriented orifices;

an actuator configured to move the cylindrical body of the spool assembly relative to the block and the first and second inserts; and
a spring configured to bias the cylindrical body toward a flow-blocking position.

13. The valve of claim 12 , wherein relative movement between the cylindrical body and the first and second inserts shifts a location of the open axial space relative to the at least a first radially oriented orifice and the at least a second radially oriented orifice.

14. The valve of claim 12 , wherein:
the first insert further includes:
a first mounting land; and
a first stem connecting the first mounting land to the first land;

the second insert further includes:
a second mounting land; and
a second stem connecting the second mounting land to the second land;

the first and second lands have about equal diameters;
the first and second mounting lands have about equal diameters that are larger than the diameters of the first and second lands; and
the valve further includes end caps configured to close off ends of the bore and to clamp the first and second mounting lands to the block.

15. The valve of claim 12 , further including a feedback element extending from an axial end of the cylindrical body, the feedback element having a conical feedback ramp, wherein the actuator further includes a follower configured to engage the conical feedback ramp.

16. The valve of claim 15 , wherein an axis of the follower is oriented about 90° relative to an axis of the conical feedback ramp.

17. A hydraulic circuit, comprising:
a tool actuator;
a pump;
a sump; and
a valve disposed between the tool actuator, the pump, and the sump, the valve including:
a block having:
a bore with a first end and a second end;
a first passage formed adjacent the first end in communication with the bore of the block and in communication with the tool actuator; and
a second passage formed adjacent the second end in communication with the bore of the block and in communication with one of the pump and the sump; and

a spool assembly disposed within the bore of the block and having:
a cylindrical body having a first end, a second end, a bore passing from the first end through the second end, at least a first radially oriented orifice that passes through a wall of the cylindrical body to communicate the first passage with the bore of the cylindrical body, and at least a second radially oriented orifice that passes through the wall of the cylindrical body to communicate the second passage with the bore of the cylindrical body;
a first insert having a first land slidably disposed inside the bore of the cylindrical body at the first end;
a second insert separate from the first insert and having a second land slidably disposed inside the bore of the cylindrical body at the second end, such that the first and second lands together at least partially define an open axial space between the first and second inserts that includes the at least a first and at least a second radially oriented orifices, wherein relative movement between the cylindrical body and the first and second inserts shifts a location of the open axial space relative to the at least a first and at least a second radially oriented orifices; and
a feedback element extending from an axial end of the cylindrical body, the feedback element having a conical feedback ramp;

a valve actuator having a follower oriented about 90° relative to an axis of the conical feedback ramp, the follower being configured to engage the conical feedback ramp and move the cylindrical body of the spool assembly relative to the block and the first and second inserts; and
a spring configured to bias the cylindrical body toward a flow-blocking position.

Assignees

• Caterpillar Inc

Inventors

• Beschorner Matthew J
• Sorokin Mikhail A

Classifications

• F16K11/22

  with an actuating member for each valve, e.g. interconnected to form multiple-way valves · CPC title

• F16K3/265

  with a sleeve sliding in the direction of the flow line · CPC title

• F16K3/0227

  Packings · CPC title

• E02F9/2296

  Systems with a variable displacement pump · CPC title

• F16K3/0218

  with only one sealing face · CPC title