Electromagnet for a hydraulic system

Patent metadata

Field	Value
Publication number	US-10662983-B2
Application number	US-201515311598-A
Country	US
Kind code	B2
Filing date	May 8, 2015
Priority date	May 16, 2014
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

An electromagnet for a hydraulic system, such as an automatic transmission of a motor vehicle. The electromagnet may include an armature chamber filled with hydraulic medium, which may be fluidically connected to hydraulic lines of the hydraulic system, and may have an armature mounted therein. The armature may have an adjustable stroke and may include a shut-off body. The armature may divide the armature chamber into an opening-side chamber facing the flow opening, and an inner chamber facing away from it. During a stroke movement of the armature, an oil exchange may occur, during which a displacement volume of the hydraulic medium overflows from the opening-side chamber into the inner chamber. The electromagnet may further include a hydraulic medium reservoir, which may store a hydraulic medium having a higher degree of purity than the hydraulic medium in the hydraulic lines and which may be fluidically connected to the opening-side chamber.

First claim

The invention claimed is:

1. An electromagnetic valve for a hydraulic system, comprising:
an armature chamber, the armature chamber configured to be filled with a hydraulic medium, and a hydraulic chamber configured to be fluidically connected to a plurality of hydraulic lines of the hydraulic system, wherein the hydraulic lines are adapted to transport hydraulic medium;
the armature chamber further comprising an armature, the armature mounted in the armature chamber such that the stroke of the armature is adjustable, the armature further comprising a shut-off body;
the armature chamber further comprising an opening-side chamber and an inner chamber, wherein the armature is moved between the opening-side chamber and the inner chamber so that the armature moving toward the opening-side chamber shrinks the opening-side chamber and expands the inner chamber and the armature moving away from the opening-side chamber expands the opening-side chamber and shrinks the inner chamber, the opening side chamber faces the plurality of hydraulic lines which are fluidically connected to the hydraulic chamber, and the inner chamber faces away from the plurality of hydraulic lines;
wherein a compensation hydraulic line is disposed in the armature and connects the opening-side chamber and the inner chamber;
wherein the armature is positioned such that a stroke movement of the armature induces an oil exchange, wherein a displacement volume of the hydraulic medium overflows from the opening-side chamber into the inner chamber;
the electromagnetic valve further comprising a hydraulic medium reservoir configured to be filled with purified hydraulic medium transported by at least one of the plurality of hydraulic lines, wherein the hydraulic medium reservoir is fluidically connected to the opening-side chamber;
wherein the purified hydraulic medium comprises gap-filtered hydraulic medium, and wherein the hydraulic medium reservoir is at least partially filled with the gap-filtered hydraulic medium;
wherein the shut-off body is disposed in a spring chamber and the hydraulic chamber such that the shut-off body is adjustably guided in its movement by an internal geometry of the spring chamber and the hydraulic chamber, such that a valve gap providing a bearing clearance is formed between the hydraulic chamber and the shut-off body;
wherein the spring chamber is connected, via at least one of the plurality of hydraulic lines, to the hydraulic medium reservoir, the hydraulic chamber configured to leak gap-filtered hydraulic medium into the spring chamber via the valve gap and through the at least one hydraulic line;
wherein the plurality of hydraulic lines comprises a drain line and a connecting hydraulic line, the drain line connecting the spring chamber to the connecting hydraulic line;
wherein the connecting hydraulic line is directly connected to the opening-side chamber from the drain line; and
wherein the connecting hydraulic line is configured to receive the displacement volume of the hydraulic medium and conduct the displacement volume via the connecting hydraulic line during the oil exchange.

2. The electromagnetic valve according to claim 1 , wherein the shut-off body of the armature comprises an axially movable piston having at least one of a first annular collar and a second annular collar;
wherein a first control edge of the first annular collar is configured to open and close a flow opening between the working connection of the electromagnetic valve and the pan-side tank connection; and
wherein a second control edge of the second annular collar is configured to open and close a flow opening between a pressure connection of a pressure source and the working connection of the electromagnetic valve.

3. The electromagnetic valve according to claim 1 , wherein a dirt-collecting hydraulic line comprises at least one hydraulic line in the set of: the plurality of hydraulic lines, the connecting hydraulic line, a branch of the connecting hydraulic line, the compensation hydraulic line disposed in the armature, and the drain line; and
wherein the dirt-collecting hydraulic line further comprises a dirt-collecting element, the dirt-collecting element comprising a permanent magnet, the dirt-collecting element configured to retain contaminations in the hydraulic medium that flows through the dirt-collecting hydraulic line during the oil exchange.

4. The electromagnetic valve according to claim 3 , wherein the dirt-collecting element is a rod-shaped permanent magnet.

5. The electromagnetic valve according to claim 3 , wherein the dirt-collecting element is a flow-permeable mesh formed from magnetic material.

6. The electromagnetic valve according to claim 3 , wherein the dirt collecting element comprises a dirt collecting contour that is formed on the inner wall of the dirt-collecting hydraulic line, the dirt collecting contour comprising a plurality of elevations and a plurality of depressions, wherein only the bottoms of each of the plurality of depressions are magnetic.

Assignees

• Audi Ag
• Volkswagen Ag

Inventors

• Schuller Dietmar
• Meyer Roland
• Corell Christian
• Rang Oliver

Classifications

• F16H2061/0253

  Details of electro hydraulic valves, e.g. lands, ports, spools or springs · CPC title

• F16K31/0613

  with cylindrical slides · CPC title

• F16K31/0693

  Pressure equilibration of the armature · CPC title

• F01L2001/34436

  Features or method for avoiding malfunction due to foreign matters in oil · CPC title

• F15B21/041 Primary

  Removal or measurement of solid or liquid contamination, e.g. filtering · CPC title