Clutch control valve assembly having armature with anti-adhesion surface treatment

Patent metadata

Field	Value
Publication number	US-11118636-B2
Application number	US-201916653480-A
Country	US
Kind code	B2
Filing date	Oct 15, 2019
Priority date	Oct 15, 2019
Publication date	Sep 14, 2021
Grant date	Sep 14, 2021

Abstract

A transmission system includes a clutch control valve assembly having an armature for adjusting a valve, rested upon metallic slide bearings under the force of gravity. The armature includes a core material that is metallic and magnetically soft, an outer thin-film coating that is non-metallic, and a backing substrate material for supporting the outer thin-filmed coating interposed the core material and the outer thin-film coating. The backing substrate material may be case hardened material derived from the core material, such as ferritic nitrocarburized (FNC) iron. The outer thin film coating may be a diamond-like carbon (DLC) material.

First claim

What is claimed is:

1. A machine comprising:
a frame structured to couple with ground-engaging elements for supporting the machine vertically above a ground surface;
a transmission system supported by the frame, and including a transmission, a clutch, and a clutch control valve assembly;
the clutch control valve assembly including a solenoid, a plurality of slide bearings that are metallic, and an armature;
the armature being rested upon the plurality of slide bearings and movable, in response to varying an electrical energy state of the solenoid, in a horizontal direction between a retracted position and an advanced position;
the armature including a core material that is metallic and magnetically soft, an outer thin-film coating that is non-metallic and in contact with the plurality of slide bearings, and a backing substrate material that is metallic and interposed the core material and the outer thin-film coating;
the clutch control valve assembly further includes a pilot valve coupled with the armature, and a pilot-operated clutch pressure control valve;
the armature includes an elongate cylindrical armature body; and
the elongate cylindrical armature body includes a hardened case, derived from the core material, forming the backing substrate material.

2. The machine of claim 1 wherein the plurality of slide bearings includes a total of two slide bearings each extending circumferentially around the elongate armature body.

3. The machine of claim 2 wherein each of the plurality of slide bearings is formed of bronze.

4. The machine of claim 1 wherein the backing substrate material includes ferritic nitrocarburized (FNC) iron.

5. The machine of claim 1 wherein a thickness of the hardened case is from about 0.005 millimeters to about 0.025 millimeters.

6. The machine of claim 5 wherein the outer thin-film coating includes a diamond-like carbon (DLC) material.

7. A transmission system for a machine comprising:
a clutch;
a clutch control valve assembly including a valve housing, a valve, a solenoid, a plurality of slide bearings that are metallic, and an armature for adjusting a position of the valve so as to adjust the clutch between an engaged state and a disengaged state;
the armature being rested upon the plurality of slide bearings under the force of gravity and movable, in response to varying an electrical energy state of the solenoid, in a horizontal direction between a retracted position and an advanced position; and
the armature including a core material that is metallic and magnetically soft, an outer thin-film coating that is non-metallic and in contact with the plurality of slide bearings, and a backing substrate material that is metallic and interposed the core material and the outer thin-film coating; and
the armature includes an elongate cylindrical armature body having a hardened case, derived from the core material, and forming the backing substrate material.

8. The transmission system of claim 7 wherein each of the plurality of slide bearings is formed of bronze.

9. The transmission system of claim 8 wherein the plurality of slide bearings includes an interference-fitted bearing and a brazed bearing, each including an inner peripheral surface in contact with the outer thin-film coating.

10. The transmission system of claim 7 wherein:
the backing substrate material is ferritic nitrocarburized (FNC) iron, and has a thickness from about 0.005 millimeters to about 0.025 millimeters.

11. The transmission system of claim 10 wherein the outer thin-film coating includes a diamond-like carbon (DLC) material.

12. The transmission system of claim 10 wherein the thickness of the backing substrate material is about 0.020 millimeters.

13. The transmission system of claim 7 wherein the outer thin-film coating includes a diamond-like carbon (DLC) material.

14. A clutch control valve assembly for a clutch in a transmission system comprising:
a valve housing;
a solenoid;
an armature;
slide bearings supporting the armature for movement within the valve housing between a retracted position and an advanced position in response to varying an electrical energy state of the solenoid;
a valve coupled with the armature and movable between an open position and a closed position, based on the movement of the armature between the retracted position and the advanced position;
the armature including a core material that is metallic and magnetically soft, an outer thin-film coating that is non-metallic and in contact with the slide bearings, and a backing substrate material that is metallic and interposed the core material and the outer thin-film coating;
the armature defines a longitudinal axis;
the valve includes a pilot valve;
the clutch control valve assembly further includes a pusher pin coupled between the armature and the pilot valve, and a pilot-operated clutch pressure control valve; and
the armature, the pilot valve, the pusher pin, and the pilot-operated clutch pressure control valve are arranged coaxially in the valve housing.

15. The clutch control valve assembly of claim 14 wherein:
the core material includes iron;
the backing substrate material includes iron and is derived from the core material; and
the outer thin-film coating includes a diamond-like carbon (DLC) material.

Assignees

• Caterpillar Inc

Inventors

• Feng Bao
• Nippert Andrew Henry
• Mohammed Qursheed Hussain

Classifications

• F16D25/14 Primary

  Fluid pressure control · CPC title

• F16D2048/0221

  Valves for clutch control systems; Details thereof · CPC title

• F16D48/02 Primary

  Control by fluid pressure · CPC title