DE102019133007A1 - magnetic valve - Google Patents

Abstract

The invention relates to a solenoid valve (10) with a first coil (19), movable armature (13), restoring element (18) and two coil inputs (21, 22). According to the invention, a second coil (20) and two further coil inputs (23, 24) are provided, the coil inputs (21 to 24) being switchable and energizable in such a way that neither of the two coils (19, 20) is energized in a rest position, - only one coil (19) is energized in one switching position, - both coils (19, 20) are energized in a holding position and are electrically in series.

Description

The invention relates to a solenoid valve with a first coil, movable armature, return element and two coil inputs. In addition, the invention relates to a circuit arrangement with a solenoid valve and a method for operating a solenoid valve with a movable armature, restoring element and two coils. The invention is preferably intended for use in a vehicle, for example in a transmission, a clutch or a pneumatic or hydraulic system.

Solenoid valves are energized for switching. The current can be reduced for subsequent holding. It is known to switch solenoid valves by pulse width modulation, see for example US 6,592,192 B1 . Disclosed is a circuit with solenoid valves for an anti-lock braking system in a hydraulic brake system. However, there the pulse width modulation serves a pulsating operation of the solenoid valve, not primarily a power reduction to hold the armature after switching.

The use of pulse width modulation to hold the armature can in principle reduce the electrical power used. However, the high number of switching operations creates a relatively high thermal load on the electronic components required for pulse width modulation. In addition, electromagnetic radiation is generated which must be shielded.

The object of the present invention is to create a solenoid valve with which a power reduction for holding the armature is possible without pulse width modulation. This applies analogously to the circuit arrangement and the method.

• - in einer Ruhestellung keine der beiden Spulen bestromt ist,
• - in einer Schaltstellung nur eine Spule bestromt ist,
• - in einer Haltestellung beide Spulen bestromt sind und elektrisch in Reihe liegen.

The solenoid valve according to the invention has the features of claim 1. In particular, a second coil and two further coil inputs are provided, the coil inputs being switchable and energizable in such a way that

• - in a rest position neither of the two coils is energized,
• - only one coil is energized in one switching position,
• - Both coils are energized in a holding position and are electrically in series.

Both coils act on the armature. In the switching position, the solenoid valve switches; in the holding position, the armature holds the position assumed by the switching. A defined voltage is applied to the solenoid valve. In the switching position, only the resistance of one coil is effective, while the other coil is preferably short-circuited, so that a relatively high current flows and a high level of power is applied. In the holding position, the two coils are in series so that the resistances of both coils are effective and only a correspondingly lower current can flow.

The geometry and electrical properties of the coils, in particular electrical resistance and magnetic flux, must be adapted to the armature to be moved and the force of the restoring element. Conductor cross-sections of the coils can be the same or differ.

The coils can be part of a common winding. With a correspondingly coordinated division of the two coils, the winding with two coils can be accommodated in the same installation space of a winding with only one coil. The solution according to the invention therefore does not require any additional installation space. This applies analogously to an embodiment with two windings, each of which contains one coil in relation to a single winding with one coil.

According to a further concept of the invention, a coil input of the first coil can be connected to a coil input of the second coil. This makes it easy to connect the two coils in series.

According to a further concept of the invention, the two interconnected coil inputs can be connected to a common connection, the two further coil inputs each being connected to their own connection. This results in only three connections in total. This enables simple interconnection and contacting.

According to a further concept of the invention, a current path can exist parallel to the non-energized coil in the switching position. The current seeks the path of least resistance and bypasses the coil via the current path. Its resistance is preferably at least one order of magnitude (factor 10 ) or two orders of magnitude lower than the resistance of the coil, so that the coil is in fact not energized.

According to a further concept of the invention, the two coils can be arranged concentrically to one another, as a radially outer coil and an inner coil. The armature is provided in the center of the coils and is axially movable. The two coils are preferably in the same position in the axial direction.

According to a further concept of the invention, it can be provided that the second coil is the outer coil and, in the switching position, only the one first is energized as the inner coil. As a result, the effective air gap between the energized coil and armature is as small as possible.

According to a further concept of the invention it can be provided that the coils are provided axially one behind the other as an upper coil and a lower coil, the movable armature being movable upwards into the holding position and downwards into the rest position. In the holding position, the movable armature is preferably completely or predominantly in the lower coil. The terms “upper coil” and “lower coil” refer to a relative position of the solenoid valve with a vertically movable armature.

According to a further concept of the invention, it can be provided that, in the switching position for moving the armature into the holding position, only the lower coil can be energized.

According to a further concept of the invention, the armature can be connected to a valve seal which closes a valve opening in the rest position. The solenoid valve is closed in the de-energized state.

The invention also relates to a circuit arrangement with a solenoid valve, see claim 10.

According to a further concept of the invention, the circuit arrangement can have two switches, namely a first switch parallel to the second coil and a second switch in series with both coils and in series with the first switch. If the second switch is open, no current flows through both coils, the solenoid valve is in the rest position. If both switches are closed, current only flows through the first coil, the second coil is bridged by the first switch and the solenoid valve is in the switch position. If the first switch is open and the second switch is closed, the current must flow through both coils one after the other so that the resistance of both coils is effective. The solenoid valve is in the holding position. To transition from the switch position to the hold position, only the first switch needs to be opened.

The method according to the invention has the features of claim 12. In particular, it can be provided that only one of the coils is energized to move the armature against the action of the reset element, and that both coils are energized to subsequently hold the armature against the effect of the reset element and are electrically in series.

According to a further concept of the invention it can be provided that the coils are provided concentrically as an inner coil and an outer coil and only the inner coil is energized to move the armature.

According to a further concept of the invention it can be provided that the coils are provided axially one behind the other as an upper coil and lower coil, the movable armature being moved upward into the holding position and downward into the rest position, and in the switching position for moving the armature into the Holding position only the lower coil is energized

• 1 ein Magnetventil mit zwei Spulen und ohne Stromfluss,
• 2 eine Schaltungsanordnung mit zwei Spulen und zwei Schaltern ohne Stromfluss,
• 3 das Magnetventil mit Stromfluss durch eine innere Spule,
• 4 die Schaltungsanordnung mit Stromfluss durch die innere Spule,
• 5 das Magnetventil mit Stromfluss durch beide Spulen,
• 6 die Schaltungsanordnung mit Stromfluss durch beide Spulen,
• 7 das Magnetventil analog 1, jedoch mit axial hintereinander angeordneten Spulen,
• 8 das Magnetventil analog 3, jedoch mit axial hintereinander angeordneten Spulen,
• 9 das Magnetventil analog 5, jedoch mit axial hintereinander angeordneten Spulen.

Further features of the invention emerge from the description and the claims. Advantageous exemplary embodiments of the invention are explained in more detail below with reference to drawings. Show it:

• 1 a solenoid valve with two coils and no current flow,
• 2 a circuit arrangement with two coils and two switches without current flow,
• 3rd the solenoid valve with current flow through an inner coil,
• 4th the circuit arrangement with current flow through the inner coil,
• 5 the solenoid valve with current flow through both coils,
• 6th the circuit arrangement with current flow through both coils,
• 7th the solenoid valve analog 1 , but with coils arranged axially one behind the other,
• 8th the solenoid valve analog 3rd , but with coils arranged axially one behind the other,
• 9 the solenoid valve analog 5 , but with coils arranged axially one behind the other.

A solenoid valve 10 has a housing 11 with a fixed anchor 12th and a movable anchor 13th on, taking the anchor 12th , 13th are arranged coaxially to each other and the movable armature 13th is movable in the axial direction. Part of the housing 11 is a sleeve 14th in which the anchor 12th , 13th are held or movable.

The moving anchor 13th is outside the sleeve 14th with a support plate 15th and a sealing element 16 provided which one to the anchors 12th , 13th coaxial valve opening 17th can seal. In 1 is accordingly shown a sealing position in which the movable armature 13th from the anchor 12th has a clear axial distance and the sealing element 16 at the valve opening 17th is present. The in 1 Sealing position shown by pressure of a return spring 18th as a return element for the movable armature 13th . Here is the return spring 18th here a spiral spring on the outside of the movable armature 13th sits and on the one hand against the housing 11 presses and on the other hand against the anchor 13th support plate protruding radially on the outside 15th .

Outside the sleeve 14th takes the case 11 a radially inner coil 19th and an outer coil 20th on. The spools 19th , 20th are preferably arranged so that they hold the two anchors 12th , 13th include wholly or predominantly. That is, one of the anchors 12th , 13th or both together are only slightly out of the contour of the coils 19th , 20th in the axial direction, preferably in the direction of the valve opening 17th . In particular, the axial length of the armature 12th , 13th together greater than the axial length of each coil 19th , 20th .

The inner coil 19th has two coil inputs 21 , 22nd on. Analogously, the outer coil has 20th two coil inputs 23 , 24 on. Here are the coil inputs 22nd , 23 with a common port 25th connected while the coil inputs 21 , 24 each with its own external connection 26th , 27 exhibit.

Parallel to the outer coil 20th is between the connectors 25th , 27 a first switch 28 switched. At the connection 27 is also a second switch 29 connected, namely in series with the two coils 19th , 20th and at the same time in series with the first switch 28 , see circuit arrangement 30th .

In the circuit arrangement 30th the 2 there is an input voltage Ue between the outer connector 26th and the second switch 29 at. There the second switch 29 is open, neither coil will 19th , 20th energized. Fixed anchor 12th and movable anchor 13th are due to the action of the return spring 18th moved apart, see 1 . magnetic valve 10 and circuit arrangement 30th are in a rest position.

In one in the 3rd and 4th The switch position shown are both switches 28 , 29 closed. As a result, there is only the inner coil 19th energized while the outer coil 20th through the first switch 28 is bridged. Only the resistance of the inner coil is effective 19th . A magnetic flux AW, which is decisive for magnetic coils, results only as a function of the input voltage, the electrical resistance R1 the inner coil 19th and their number of turns n1: $${\text{AW}}_{\text{Switch position}}=\text{Ue / R1}\times \text{n1}$$

After switching the solenoid valve 10 a smaller force around the movable armature is sufficient 13th in the in the 3rd and 5 in the raised position shown. That's why the first switch 28 opened and the second switch 29 stays closed so all of the current goes through both coils 19th , 20th must flow. The resistances are accordingly R1 , R2 and number of turns n1, n2 of both coils 19th , 20th relevant. As a flooding AW for those in the 5 , 6th shown holding position results: $${\text{AW}}_{\text{Holding position}}=\text{Ue /}\left(\text{R1}+\text{R2}\right)\times \left(\text{n1}+\text{n2}\right)$$

In relation to a solenoid valve with only one coil, in the version provided here with two coils for holding the armature in the holding position only about half of the starting current effective in the switching position is required. This results from the switching position to the holding position and preferably with the same number of turns n1, n2 and the same resistances R1 , R2 the following ratio of the currents: $${\text{I.}}_{\text{Switch position}}/{\text{I.}}_{\text{Holding position}}=2$$

From this it is clear that by switching on the outer coil 20th Considerable energy savings are possible in the holding position. Possible heat losses are reduced. The high thermal load on electronic components resulting from pulse width modulation is avoided.

In practice, numbers of turns can be n1, n2 and resistances R1 , R2 be designed differently. It is necessary to coordinate the coils 19th , 20th on the input voltage Ue and the force of the return spring 18th . A safe switchover from the rest position to the switch position and the holding of the holding position must be guaranteed. In any case, the holding current required to maintain the holding position can be significantly lower than the starting current required for switching from the rest position to the switching position.

With the formation of a winding with two coils in the same winding space as with a solenoid valve with only one coil, the current and power consumption in the holding position can be significantly reduced. Equation 2 results in a higher value for the flow AW in the holding position than required, but the power consumption is halved with the same number of turns n1 and n2.

Another advantage of the solution according to the invention is that, due to the reduced power consumption, a longer activation (duty cycle) is possible than with a single-coil winding. In a specific example, a single Coil winding have a power consumption of 17 watts. With a two-coil winding in the same installation space, the coil 19th to wear 26th Watt and the other coil 20th 14th Watts of power consumption. The series connection reduces the power consumption in holding mode to 12 watts.

The 7th , 8th , 9 show an alternative embodiment of the solenoid valve 10 . The reference numbers of the 1 , 3rd , 5 were taken over. The spools 19th , 20th are not arranged radially inside and outside, but positioned radially the same and axially one behind the other. The effective coil is in the switching position 19th at the height of the movable anchor 13th arranged and the other coil 20th at the height of the anchor 12th . Preferably the movable armature extends 13th in the holding position by the coil 19th completely through. In the rest position, a small section of the anchor protrudes 13th out of the coil 19th out towards the valve opening 17th . The circuit arrangements of the 2 , 4th , 6th also apply to the solenoid valves of the 7th , 8th , 9 .

The circuit arrangements or solenoid valves shown are preferably provided in a vehicle, for example in a transmission, a clutch or a pneumatic or hydraulic system. A particularly preferred application relates to gear actuators in automated manual transmissions.

List of reference symbols

10

magnetic valve

11

casing

12th

Fixed anchor

13th

movable anchor

14th

Sleeve

15th

Support plate

16

Sealing element

17th

Valve opening

18th

Return spring

19th

inner coil

20th

outer coil

21

Coil input (inner coil)

22nd

Coil input (inner coil)

23

Coil input (outer coil)

24

Coil input (outer coil)

25th

common connection

26th

external connection

27

external connection

28

first switch

29

second switch

30th

Circuit arrangement

R1

Coil resistance 19

R2

Resistance of coil 20

Ue

Input voltage

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 6592192 B1 [0002]

Claims (14)

Solenoid valve (10) with first coil (19), movable armature (13), restoring element (18) and two coil inputs (21, 22), characterized by a second coil (20) and two further coil inputs (23, 24), the Coil inputs (21 to 24) can be switched and energized in such a way that - none of the two coils (19, 20) is energized in a rest position, - only one coil (19) is energized in a switching position, - both coils (19) in a holding position , 20) are energized and are electrically in series. Solenoid valve after Claim 1 , characterized in that a coil input (22) of the first coil (19) is connected to a coil input (23) of the second coil (20). Solenoid valve after Claim 2 , characterized in that the two interconnected coil inputs (22, 23) are connected to a common connection (25) and that the two further coil inputs (21, 24) are each connected to their own connection (26, 27). Solenoid valve according to one of the Claims 1 to 3rd , characterized in that in the switching position there is a current path parallel to the non-energized coil (20). Solenoid valve according to one of the Claims 1 to 4th , characterized in that the two coils (19, 20) are arranged concentrically, as a radially outer coil (20) and an inner coil (19). Solenoid valve after Claim 5 , characterized in that the second coil (20) is the outer coil and in the switching position only the first coil (19) is energized as the inner coil. Solenoid valve according to one of the Claims 1 to 4th , characterized in that the coils (19, 20) are provided axially one behind the other as an upper coil (20) and lower coil (19), the movable armature (13) being movable upwards into the holding position and downwards into the rest position. and in the holding position it is wholly or predominantly in the lower coil (19), Solenoid valve after Claims 7 , characterized in that in the switching position for moving the armature (13) into the holding position only the lower coil (19) can be energized. Solenoid valve according to one of the Claims 1 to 6th , characterized in that the movable armature (13) is connected to a valve seal (16) which closes a valve opening (17) in the rest position. Circuit arrangement (30) with a solenoid valve (10) according to one of the Claims 1 to 7th . Circuit arrangement according to Claim 8 , characterized by two switches (28, 29), namely a first switch (28) parallel to the second coil (20) and a second switch (29) in series with both coils (19, 20) and in series with the first switch ( 28). Method for operating a solenoid valve (10) with a movable armature (13), a restoring element (18) and two coils (19, 20), wherein only one of the coils ( 19, 20) is energized, and that both coils (19, 20) are energized to subsequently hold the armature (13) against the action of the restoring element (18) and thereby place them electrically in series. Procedure according to Claim 12 , characterized in that the coils (19, 20) are provided concentrically as inner coil (19) and outer coil (20) and only the inner coil (19) is energized to move the armature (13). Procedure according to Claim 12 , characterized in that the coils (19, 20) are provided axially one behind the other as an upper coil (20) and lower coil (19), the movable armature (13) being moved upwards into the holding position and downwards into the rest position and wherein in the switching position for moving the armature (13) into the holding position only the lower coil (19) is energized.

Images