DE102007010213B3 - Electromagnetic pressure regulating valve for motor vehicle, has seat valve that is formed between piston valve and inner wall of valve housing, and another seat valve that is arranged in piston valve for pressure balance - Google Patents

Abstract

The valve (1) has a valve unit (10) that is provided with a valve housing (101), an inlet connector (102), a load connector (103) and a piston valve (104), which are slidable opposite to the valve housing and equipped with a channel-like recess (105) for fluid guidance. An actuator (20) includes an electromagnetic coil (201) and a slidable armature (202) that acts together with the piston valve. A seat valve (2) is formed between the piston valve and an inner wall of the valve housing. Another seat valve (3) is arranged in the piston valve for pressure balance. An independent claim is also included for a method for controlling an electromagnetic regulating valve as an opener.

Description

The The invention relates to an electromagnetic control valve with a Valve unit and an actuating unit according to the preamble of claim 1. Furthermore, the invention relates to a method of control an electromagnetic control valve.

In the publication EP 1 591 856 A1 is described an electromagnetic pressure control valve with a magnetic part and a valve member. The magnet part has an electrical coil and a displaceably mounted armature. The valve member includes an inlet, a return, a consumer port and a cooperating with the armature of the solenoid valve member, which has a slide and a poppet valve. The slider closes in the inactive state, in which no current flows through the coil, the flow of a fluid from the inlet to the consumer connection or to the return line. About the return of the fluid is collected in a reservoir from which it is in turn pumped into the inlet of the pressure control valve. Such valves can be used with a nearly linear control of the pressure, for example for the hydraulic control of actuators for camshaft adjustment or in the transmission of a motor vehicle use.

Also from the publication EP 1 004 066 B1 known is an electromagnetic pressure control valve with a magnetic part, which consists of an electrically controllable coil, a coil core and a slidably guided anchor. The pressure regulating valve also comprises a valve part which has an inlet, a return, a consumer connection and a valve element cooperating with the armature of the magnet part. In the valve part two seat valves are formed with the inclusion of the valve wall, of which the first has a closing member and the second is used to control the fluid flow with respect to the return. Between the first and the second valve, a bypass line to the load port is arranged. Thus, there is a direct connection between the consumer connection and the return line via the bypass line, through which a pressure medium can flow from the consumer connection to a tank connected to the return line.

In addition, from the document DE 199 06 250 A1 a control valve with three ports for connecting a consumer with a pressure source and with a pressure medium reservoir known. The pressure medium reservoir consists of a pilot stage, designed as an electromagnetically actuated seat valve and a main stage, designed as a slide valve. The slider is controllable via an adjustable by means of the poppet valve pressure difference. To improve the control behavior and its reproducibility of the valve seat of the seat valve is formed on the slide and the seat valve for direct connection between the consumer and the pressure medium reservoir integrated.

From the DE 103 23 595 A1 Proportional control valve assemblies can be taken in two different embodiments, which by means of force difference on working surfaces of a main piston, the front and rear of the working piston via an orifice with each other, at smaller pressure differences (delta p <2 bar) facilitate the opening of the valve in hydraulic reflux, to allow faster drainage in the discharge direction of a reciprocating piston.

Furthermore, from the document DE 197 47 307 A1 a multi-way valve with a valve housing axially movably arranged seat valve body and with a valve housing movable in the valve slide, wherein the valve slide is mechanically coupled to the seat valve body. The valve spool is guided in the valve housing as a hollow slide and connects a pressure medium consumers either with a pressure medium source or with a pressure medium collector. The seat valve body has a ball seat and is an integral part of a valve spool coaxially penetrating plunger, at its end facing away from the seat valve body end a proportional solenoid is arranged. The multi-way valve forms a continuously controllable by means of proportional solenoids and coupled with a poppet valve spool valve that can be used for slip-controlled electro-hydraulic brake systems. In connection with a hydraulic brake is a valve from the DE 44 41 150 A1 Known in which can be short-circuited in the event of a wheel slip in a memory via a downstream ball seat valve via a arranged in the outflow direction aperture at electronically detected pressure exceeded by the master cylinder pressure peaks.

For completeness reasons is still the DE 6 980 44 26 T2 cited, which describes a three-way valve, the piston is divided into two parts with two seats in a coaxial arrangement. The seats work in opposite directions. From the DE 203 21 276 U1 is the same principle in connection with a convertible roof control known, in which the flow rate through the counteracting two ball seat valves in response to the control current is adjustable. Between the balls of the ball seat valve, a plunger is arranged, which opens the smaller ball seat valve, while the larger ball seat valve closes.

at the solutions mentioned In the prior art, it is assumed in control valves that for controlling a poppet valve via the magnetic control for disposal standing force is readily sufficient. For larger pressurized surfaces or higher To press However, the problem can emerge that with conventional magnet controls the control force to control poppet valves is too low.

Of the Invention is based on the object, an electromagnetic control valve so educate that a large area with Pressure impinged seat valve for fluid control can be reliably controlled can.

The Invention is characterized by the features of claim 1 with respect to a electromagnetic control valve and by the features of claim 13 in terms of the control of an electromagnetic control valve reproduced. The others refer back claims relate to advantageous embodiments and further developments of the invention.

The Invention includes an electromagnetic control valve, with a valve unit, comprising at least one valve housing, an inlet connection, a consumer port and a spool valve, opposite to the Sliding valve housing and equipped with at least one channel-like recess for fluid guidance is. Furthermore, the electromagnetic control valve includes an actuator, comprising at least one electromagnetic Coil and a cooperating with the spool sliding anchor. To the solution The task is between the spool and the inner wall of the valve housing a first seat valve is formed and for pressure equalization is a second seat valve arranged in the spool.

The Control valve has in its valve housing so a movably guided spool the means of the actuator in its position in the axial direction is adjustable. The respective control position of the piston valve is by an appropriate energization of the electromagnetic Coil continuously changeable. The invention is based on the consideration that the in operation, pressurized surfaces of the first and second Seat valve differ so far that one with different Force control controllable two-stage seal is formed. The second seat valve in the spool valve may be due to its relative slightly pressurized surface with correspondingly lower Power open become. This results in a pressure equalization between the supply line and the interior of the piston valve instead. Is a pressure equalization done, lets the first seat valve largely independent of pressure to control the fluid flow deploy. In this case, the second seat valve can contribute to Supply control of the fluid flow.

The Seats work lined up, that means the inside seat is for the pre-opening in front of the outside Headquarters determined. Due to the same width of the printing surfaces of the Piston is made a pressure balance. The blocking effect The valve is characterized by a combination of seat valve and spool valve manufactured in the locked position, a so-called double lock or double shut-off function. The ball seat valve locks in the closed position, that means in the de-energized state, the flow of the fluid. The fluid is volume controlled by the valve. Through the precursor formation through the ball seat valve and the subsequent, after the opening the ball seat valve, prevailing pressure balance on the spool let yourself the volume of the fluid almost force and thus pressure independent on the control electrical control current to the electric magnet.

The Control valve according to the invention is in operation as an opener used and is thus closed without leakage in the de-energized state. The force required to open of the second seat valve for a pressure balance in the piston is decisive for the dimensioning of the entire Adjusting unit. The smaller the pressure area A2 of the second seat valve is designed, the smaller can also the structural components of the actuator even at higher fluid pressures on Inlet connection to be dimensioned.

Of the particular advantage is that through the second seat valve a simple sealing principle is available for pressure equalization. Due to the comparatively small diameter of the pressurized area the second valve can already be opened with little force. As a result, the setting unit can be dimensioned correspondingly small. Furthermore, by the gradual opening of the two seat valves at the consumer connection initially closed control edge the fluid flow with the spool valve without disturbing pressure surges can be regulated. In particular, the control valve is leak-free in the de-energized state.

In an advantageous embodiment of the invention, the first seat valve between inlet port and consumer port on the front side of the piston valve be arranged. By an arrangement on the front side stands in the further course along the spool in the valve body enough space for controlling the consumer connections available.

Prefers It can be provided that the control edge located on the spool valve the first seat valve is conical or spherical. hereby becomes the pressure loss of the fluid flowing through the poppet valve reduced accordingly.

advantageously, can the first seat valve in the de-energized state of the actuator by a cooperating with the end face of the spool be closed first spring, which is against the inner wall of the valve housing supported. The Spring exercises a force on the spool that caused by the anchor Counteracts force and in the de-energized state a defined closing state causes.

In Preferred embodiment of the invention may be an axial piston valve arranged plunger with the anchor and a closing member in operative connection. From the axially directed introduction of force the ram through the piston valve, the closing member is controlled without disturbing transverse forces.

Especially It is advantageous if the closure member is conical or spherical. As a result, which has a favorable effect on the flow conditions of the fluid Symmetry of the closing element used.

advantageously, can the axially arranged in the spool plunger and the closing member mechanically be decoupled. With the valve open is by the closing member flowing past Fluid flow causes due to the flow conditions at the control edges the closing member centered by itself.

Prefers can the operative connection of plunger, spool and armature of the adjusting unit be designed so that in operation by the movement of the armature, the second seat valve for pressure equalization opens in front of the first seat valve. The first seat valve should in particular open only at the time the pressure equalization inside the spool completed is. This gradual opening guaranteed an optimal control of the fluid flow over the control edge of the first Poppet valve.

advantageously, can the relationship the pressurized surfaces of the second seat valve A2 and the first seat valve A1 smaller to be 0.3. The relatively large, pressurized surface of the first seat valve A1 may even make an opening impossible. At least one would spontaneous opening but a corresponding pressure surge inside the piston valve cause. The area ratios are in practice to be determined so that the relevant proportion of the fluid flow with the larger first Seat valve is regulated, whereas the intended for pressure equalization second seat valve nonetheless provide a minor contribution can. In contrast, the second seat valve is designed to be so small that the shooting power reliably overcome with the magnet acting on the sliding armature can be. Nevertheless, over the second seat valve for fast pressure equalization sufficient amount of fluid can be passed into the interior of the piston valve.

In In a further advantageous development, the second seat valve in the de-energized state of the actuator by cooperating with the closing member be closed second spring. The spring force becomes the second Seat valve independent from overpressure the fluid in the feed reliably locked.

Prefers can the first spring and the second spring on the high pressure side of the Plunger be arranged. Both springs can be different Winding radii also mesh. The feathers are arranged that in the first place again in the longitudinal direction of the spool acting axial forces be generated.

advantageously, For example, the spool can be designed with a large sealing length on the consumer connection be. This increases the closing function and provides another contribution that the control valve in the de-energized Condition is leak-free. The sleeve-like Scope of the spool is running on the inside of the valve body in a longer one Section in touching Way and thus seals over the Inner wall of the valve housing and its corresponding peripheral portion over a large area and along a longer route the valve in relation to the drain. The constructive sealing surface realization is reduced the leakage and increased the sealing effect of the valve.

One Another aspect of the invention includes a method of control of the electromagnetic according to the invention Control valve as normally closed one. This is in the energized state by the movement of the armature the second seat valve opened, whereby the fluid for pressure equalization inside the piston valve flows. The first seat valve is controlled to regulate the fluid flow, as soon as the pressure equalization is complete or almost completely took place. With the opening of the first seat valve are also due to the displacement of the piston valve the consumer connections driven.

The invention is based on the consideration that the method of operation for controlling the electromagnetic control valve going out of hibernation. The control valve is an opener in which both seat valves are closed in the non-energized initial state and the consumer connections are closed by the piston valve. The fluid flow is completely sealed off.

Becomes the valve is energized, then a small force is sufficient to pass through the movement of the armature first, the second seat valve for pressure equalization to open. From this time flows Fluid for pressure equalization inside the piston valve. Only when the Pressure equalization complete or almost completely has taken place Open the first seat valve with little force. About the first seat valve is then the largest share controlled the fluid flow. By opening the first seat valve are also driven by a displacement of the piston valve, the consumer connections. The second, for the pressure equalization, Poppet valve flowing Fluid content has a subordinate overall fluid flow Importance. This gradual opening guaranteed an optimal control of the fluid flow over the control edge of the first Seat valve without disturbing Pressure surges.

The Invention is achieved by further preferred embodiments with reference to schematic drawing closer explained.

In this shows:

1 an electromagnetic control valve in cross section.

each other corresponding parts are provided with the same reference numerals.

1 shows an electromagnetic control valve 1 with a valve unit 10 and an actuator 20 in cross section. The valve unit 10 includes a valve housing 101 , an inlet connection 102 , a consumer connection 103 and a piston valve 104 , opposite the valve body 101 slidable and with a channel-like recess 105 is equipped for fluid guidance. The actuator 20 includes an electromagnetic coil 201 and one with the piston valve 104 interacting sliding anchor 202 ,

Between the piston valve 104 and the inner wall of the valve housing 101 is a first seat valve 2 designed, for pressure equalization is a second seat valve 3 in the piston valve 104 arranged. The first seat valve 2 located between inlet connection 102 and consumer connection 103 frontally on the spool 104 , The on the piston valve 104 located control edge 106 of the first seat valve 2 is conical in this case.

The first seat valve 2 is in the de-energized state of the actuator 20 through one with the front side 107 of the piston valve 104 cooperating first spring 108 closed against the inner wall of the valve body 101 supported. In addition to the spring force acts in the closed state, another caused by the fluid force by the at the inlet connection 102 existing overpressure of the fluid arises.

An axial in the piston valve 104 arranged ram 109 stands with the anchor 202 and the closing member 110 in active connection. The closing element 110 is spherical. Here are the in the piston valve 104 arranged ram 109 and the closing member 110 mechanically decoupled, allowing the ball to move freely in the valve seat and center.

The operative connection of plunger 109 , Piston valve 104 and anchor 202 the actuator 20 is through a slightly longer pestle 109 designed so that in operation by the movement of the armature 202 the second seat valve 3 to equalize the pressure in front of the first seat valve 2 opens.

In 1 is the ratio of the pressure areas of the second seat valve 3 A2 and the first seat valve 2 A1 about 0.2.

The second seat valve 3 is in the de-energized state of the actuator 20 by one with the closing member 110 cooperating second spring 111 locked. Here are the first spring 108 and the second spring 111 on the high pressure side of the piston valve 104 arranged.

The principle according to the invention can be used in a volume control valve or a volume flow control valve, a so-called VCV, for diesel common rail systems, in particular the high-pressure diesel pump. The volume to be adjusted via the valve can be determined very strongly decoupled from the pressure fluctuations, which may be pulsating due to the pump, before the valve by adjusting the electrical current. The flow adjusts the flow rate, the volume volume, almost infinitely. A valve according to the principle of the invention is characterized by reduced leakage quantities. Interestingly, the valve is also characterized by the good volume flow control. Furthermore, the smallest possible magnet can be used. This means that the winding number of the coil can be reduced, which in turn means that the diameter of the valve can be reduced. The movable piston valve of the valve serves as a stop for the second valve at one end. A moving component, the piston valve, of the valve is also a reference component which forms the valve seat for a lying in its extended center second valve. The second valve is a pilot control stage for the main control stage, via which the volume quantity can be set as a priority. The second valve results from the piston valve, which is part of the first valve, as a second sleeve (in the valve sleeve) and another plunger-like or closing ball-like valve. Spatially, therefore, the second valve is located in front of the first valve. It can also be said that the second valve is arranged centrally to parts of the first valve. To move the spool of the main control stage requires due to the pressure compensation only a reduced force required to provide the electrical coil of the magnetic part of the valve available.

1

electromagnetic control valve

2

first poppet valve

3

second poppet valve

10

valve unit

101

valve housing

102

inflow connection

103

consumer connection

104

spool

105

channel-like recess

106

control edge

107

front of the piston valve

108

first feather

109

tappet

110

closing member

111

second feather

20

actuator

201

electromagnetic Kitchen sink

202

anchor

A1

pressurized area of the first seat valve

A2

pressurized area of the second seat valve

Claims (13)

Electromagnetic control valve ( 1 ) - with a valve unit ( 10 ), comprising at least one valve housing ( 101 ), an inlet connection ( 102 ), a consumer connection ( 103 ) and a piston valve ( 104 ), opposite the valve housing ( 101 ) displaceable and with at least one channel-like recess ( 105 ) is equipped for fluid guidance, - with an actuating unit ( 20 ) comprising at least one electromagnetic coil ( 201 ) and one with the piston valve ( 104 ) cooperating displaceable anchors ( 202 ), characterized in that between the piston valve ( 104 ) and the inner wall of the valve housing ( 101 ) a first seat valve ( 2 ), and - that for pressure equalization a second seat valve ( 3 ) in the piston valve ( 104 ) is arranged. Electromagnetic control valve according to claim 1, characterized in that the first seat valve ( 2 ) between inlet connection ( 102 ) and consumer connection ( 103 ) on the front side of the spool ( 104 ) is arranged. Electromagnetic control valve according to claim 1 or 2, characterized in that the piston slide ( 104 ) located control edge ( 106 ) of the first seat valve ( 2 ) is conical or spherical. Electromagnetic control valve according to one of claims 1 to 3, characterized in that the first seat valve ( 2 ) in the de-energized state of the actuator ( 20 ) by one with the front side ( 107 ) of the piston valve ( 104 ) cooperating first spring ( 108 ) is closed, which against the inner wall of the valve housing ( 101 ) is supported. Electromagnetic control valve according to one of claims 1 to 4, characterized in that an axial in the piston slide ( 104 ) arranged plunger ( 109 ) with the anchor ( 202 ) and a closing member ( 110 ) is in operative connection. Electromagnetic control valve according to claim 5, characterized in that the closing member ( 110 ) is conical or spherical. Electromagnetic control valve according to claim 5 or 6, characterized in that the axial in the spool ( 104 ) arranged plunger ( 109 ) and the closing member ( 110 ) are mechanically decoupled. Electromagnetic control valve according to one of claims 5 to 7, characterized in that the operative connection of plunger ( 109 ), Piston valve ( 104 ) and anchors ( 202 ) of the actuator ( 20 ) is designed so that in operation by the movement of the armature ( 202 ) the second seat valve ( 3 ) to equalize the pressure in front of the first seat valve ( 2 ) opens. Electromagnetic control valve according to one of claims 1 to 8, characterized in that the ratio of the pressure-loaded surfaces of the second seat valve ( 3 ) A2 and the first seat valve ( 2 ) A1 is less than 0.3. Electromagnetic control valve according to one of claims 1 to 9, characterized in that the second seat valve ( 3 ) in the de-energized state of the actuator ( 20 ) by a with the closing member ( 110 ) cooperating second Fe of the ( 111 ) is closed. Electromagnetic control valve according to claim 10, characterized in that the first spring ( 108 ) and the second spring ( 111 ) on the high pressure side of the piston valve ( 104 ) are arranged. Electromagnetic control valve according to one of claims 1 to 11, characterized in that the spool ( 104 ) at the consumer connection ( 103 ) is formed with a large sealing length. Method for controlling an electromagnetic control valve as an opener according to one of claims 1 to 12, by the following steps: - in the energized state, the movement of the armature ( 202 ) the second seat valve ( 3 ), whereby the fluid for pressure equalization in the interior of the piston valve ( 104 ), - the first seat valve ( 2 ) is controlled to regulate the fluid flow as soon as the pressure equalization has completely or almost completely taken place, - with the opening of the first seat valve ( 2 ) are also due to the displacement of the piston valve ( 104 ) the consumer connections ( 103 ).