Pressure control valve for the open-loop or closed-loop control of a pressure of a fluid in a pilot pressure chamber, and vibration damper having such a pressure control valve
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-02-06
- Publication Date
- 2026-03-25
AI Technical Summary
Existing pressure control valves for vibration dampers in motor vehicles face challenges in maintaining consistent damping behavior, especially at low current flow, leading to varying damping characteristics when electrical energy fails, resulting in a complex device structure to ensure a medium damping characteristic as a failsafe.
A pressure control valve design with a pilot seal and actuating device that allows repeatable adjustment of damping behavior, even at low current, using a plunger with a pilot seal that moves between positions to control fluid flow through passage channels, and a failsafe seal to maintain operation without electrical energy, ensuring consistent damping.
The solution enables consistent damping behavior across all current ranges, including low current conditions, and ensures the vibration damper operates with a predetermined damping characteristic even without electrical power, simplifying the device structure while maintaining reliability.
Smart Images
Figure EP2024052861_21112024_PF_FP_ABST
Abstract
Description
[0001] Pressure control valve for controlling or regulating a pressure of a fluid in a pilot pressure chamber and vibration damper with such a pressure control valve
[0002] The present invention relates to a pressure control valve for controlling or regulating a pressure of a fluid in a pilot pressure chamber having the features of patent claim 1. Furthermore, the present invention relates to a vibration damper having such a pressure control valve.
[0003] Pressure control valves are already known from the prior art in various designs. For example, in the prior art, pressure control valves of this generic type are used in vibration dampers in motor vehicles, wherein a damping characteristic of the pressure control valve depends on a volume flow of the fluid used flowing through the proportional valve. Depending on the volume flow, a softer, more comfortable damping or a harder, more sporty damping can be set. Vibration dampers use an energizable actuating device with which several damping characteristics can be specified by the driver or automatically adjusted by an on-board computer depending on the driving condition of the motor vehicle or the condition of the floor covering over which the motor vehicle is currently moving.
[0004] The fluid can be hydraulic or pneumatic, typically hydraulic fluid or compressed air. Pilot pressure chambers in hydraulically or pneumatically operated devices serve to control or regulate pilot-operated valves, often also designed as hydraulic or pneumatic spools. If pilot-operated valves are designed as proportional valves or proportional spools, the volume flows flowing through the proportional valve or proportional spool can be continuously adjusted within certain limits using the pressure in the pilot pressure chamber.
[0005] Such pressure control valves have proven themselves in the past, but it must always be ensured that a fail-safe mechanism is in place in the event of a failure of the electrical power and consequently the failure of the pressure control valve actuation device. This ensures that the vehicle can continue to be operated with a specific damping characteristic even in the event of a failure of the electrical power. In this case, a medium damping characteristic is usually aimed for, which is neither too hard nor too soft.
[0006] These requirements result in a relatively complex design of the device, in particular of the vibration damper, as can be seen, for example, from US 2016 0 091 044 A1 and WO 2016 066 314 A1. The design is primarily complex because several slides have to be used. Further vibration dampers are disclosed in US 2016 0 369 862 A1, JP 2009 115 319 A, US 5 147 018 A, WO 2011 023 351 A1 and US 2005 0 016 086 A1. In particular, the vibration damper disclosed in EP 2 678 581 B1 offers medium damping characteristics even in the "failsafe" mode.
[0007] A disadvantage of the pressure control valves known from the prior art has been that in the lowest control range the control or regulation of the pressure of the fluid varies greatly, which can cause the damping behavior to vary greatly, particularly when the current supply to the actuating device is low.
[0008] This is where the present invention comes in.
[0009] The present invention is dedicated to the object of proposing a generic pressure control valve which expediently eliminates the disadvantages known from the prior art. The proposed pressure control valve should enable a repeatable adjustment of the damping behavior even with a low current supply in the lowest control range. A further object is to provide a pressure control valve for regulating the pressure of a fluid in a pilot pressure chamber, which pressure control valve is simple in design and regulates the pressure in the pilot pressure chamber to a definable value even when no electrical energy is available to power the actuating device. Furthermore, one embodiment of the present invention is based on the object of creating a device with which the pressure of the fluid in the pilot pressure chamber can be regulated and which can be operated with such a pressure control valve.
[0010] This object is achieved by a pressure control valve having the features of patent claim 1 and a vibration damper having the features of patent claim 18.
[0011] Further advantageous embodiments of the present invention are specified in the subclaims.
[0012] Generic pressure control valves with the features of patent claim 1, for controlling or regulating a pressure of a fluid in a pilot pressure chamber, have a valve housing with at least one inlet and at least one outlet. The at least one inlet can be fluidically communicated with the pilot pressure chamber. In addition, the valve housing has a first valve seat arranged between the at least one inlet and the at least one outlet and a second valve seat which are arranged in a pilot valve chamber. The pilot pressure chamber is connected to the at least one outlet by means of a first passage channel and to the at least one inlet by means of a second passage channel. In addition, the pressure control valve according to the invention has a tappet with a pilot seal, wherein the tappet can be moved along a longitudinal axis between a first and a second position by means of an energizable actuating device.The pilot seal comprises a sealing section with a first sealing surface and a second sealing surface, wherein the first sealing surface and the second sealing surface are arranged on opposite sides in the longitudinal axis. In an unactuated state of the actuating device, the pilot seal is arranged in the first position by means of a return spring, in which the first sealing surface of the pilot seal bears sealingly against the first valve seat and closes the first passage channel. In the actuated state of the actuating device, the tappet is in the second position, in which the second sealing surface of the pilot seal bears sealingly against the second valve seat and closes the second passage channel.According to the invention, however, the pilot seal has a stop section that is spring-loaded relative to the sealing section and can come into contact with a stop between the first end position and a second end position before the second end position is reached. The present invention is based on the idea of proposing a pressure control valve that enables comfortable damping behavior.
[0013] When the actuating device is supplied with a small amount of current, for example with approximately 0.4A, the plunger with the pilot seal is moved from the first position towards the second end position. The pilot seal initially encounters a stop and comes to rest there in a position referred to here as the contact position of the plunger. In this position, the fluid can flow from the at least one inlet through the second passage channel into the pilot valve chamber and can flow out through the first passage channel towards the at least one outlet.
[0014] When the actuating device is subjected to a higher current, the pilot seal is overpressured and the second valve seat, which can also be called the pilot seat, closes. In other words, the sealing section is displaced, particularly elastically, relative to the stop section, and the sealing section, or more precisely the second sealing surface, lies sealingly against the second valve seat and closes the second passage channel. In this state, the fluid cannot flow from the at least one inlet through the pilot valve chamber to the at least one outlet.
[0015] A further development of the present invention provides that in the first position, i.e. in the unactuated state of the actuating device, a first distance measured in the longitudinal axis between the second sealing surface and the second valve seat is greater than a second distance measured in the longitudinal axis between the stop section and the stop. Thus, in an undeformed state of the pilot seal, the second sealing surface is arranged at a distance from the second valve seat even when the stop section bears against the stop. The fluid can consequently flow from the at least one inlet through the second passage channel.
[0016] A further development of the present invention provides that the pilot seal has at least one flow-through opening. The at least one flow-through opening is preferably formed beyond the sealing section and more preferably formed at least between the sealing section and the stop section. The at least one flow-through opening can also extend completely or partially over the stop section. In the contact position, the fluid can flow through the pilot seal through the at least one flow-through opening. The at least one flow-through opening can be shaped as desired and allows fluid communication between the sides of the pilot seal that are opposite one another in the longitudinal axis.
[0017] Furthermore, it has proven advantageous if the pilot seal has a spring section. The spring section preferably connects the stop section and the sealing section and enables a spring-elastic displacement of the sealing section relative to the stop section. In a preferred embodiment, the spring section can be designed as a web connecting the stop section and the sealing section.
[0018] According to a further preferred embodiment, the pilot seal comprises a disc-shaped flat spring element. It is particularly preferred if the stop section, the spring section, and at least partially the sealing section are formed integrally, preferably as a disc-shaped element. Disc-shaped flat spring elements can be easily designed for the respective application and can be manufactured simply and cost-effectively. Such disc-shaped flat spring elements have also proven to be reliable.
[0019] A further development of the present invention provides that the pilot seal has a sealing element comprising the first sealing surface and / or a second sealing surface. In particular, it is preferred if a sealing element is arranged in the longitudinal axis on opposite sides of the disc-shaped flat spring element. The shape of the respective sealing element can be adapted to the shape of the respective valve seat, wherein the respective sealing element is preferably circular or annular. Furthermore, it is preferred if the two sealing elements are structurally identical.
[0020] According to a further preferred embodiment, the pilot valve chamber is formed in the valve housing, wherein the pilot valve chamber is preferably enclosed by the valve housing. The first valve seat and the second valve seat are arranged in the pilot valve chamber along the longitudinal axis on opposite sides of the valve housing, wherein the first valve seat frames or surrounds an opening of the first passage channel and the second valve seat frames or surrounds an opening of the second passage channel.
[0021] It has also proven advantageous if the valve housing comprises a wall section that has the first valve seat and the first passage channel. The wall section can be designed in the manner of a valve housing and preferably closes off the pilot valve chamber on one side along its longitudinal axis, thereby resulting in an advantageous design of the valve housing.
[0022] Furthermore, it has proven advantageous if the wall section has at least one through-bore which forms a bypass around the first valve seat. The bypass enables fluid communication between the pilot valve chamber and a side of the wall section facing away from the pilot valve chamber, both in the first position and in the second position of the tappet, and enables fluid communication between the pilot valve chamber and the at least one outlet, in particular when the tappet is in the first position and the pilot seal is in sealing contact with the first valve seat.
[0023] Furthermore, it has proven advantageous if a fail-safe seal is arranged on the side of the wall section facing away from the first valve seat, which fail-safe seal is pre-tensioned against the wall section and can bear against the wall section in such a way that the through-bore is closed. The fail-safe seal pre-tensioned against the wall section can predetermine a pressure in the pilot valve chamber at which the through-bore is released and the fluid can flow from the pilot valve chamber through the through-bore to at least one outlet. The through-bore and the fail-safe seal interacting with the through-bore ensure that the shock absorber can continue to operate with a specific damping characteristic even in the event of a failure of the electrical power.The damping characteristics can be defined by selecting the preload of the failsafe seal, which is typically chosen so that it is neither too hard nor too soft.
[0024] An advantageous development of the present invention provides that the wall section is formed by a valve housing cover part. The valve housing cover part can, for example, be designed as a disc-shaped component and, together with a main valve housing part, enclose the pilot valve chamber at least in part.
[0025] A further development of the present invention provides that the valve housing comprises a second wall section which comprises the second valve seat or the stop and the second valve seat. The second wall section can furthermore also comprise the second passage channel, wherein the second passage channel is preferably designed as a bore. The second wall section is preferably arranged in the longitudinal axis on the side of the valve housing opposite the first wall section, wherein the second wall section can be formed integrally with the main valve housing part. According to one exemplary embodiment, for example, the stop can be formed on the main valve housing part and the second valve seat on the second wall section. According to another exemplary embodiment, both the stop and the second valve seat can be formed on the second wall section.
[0026] A further development of the present invention provides that the second wall section comprises an insert bushing. The insert bushing can be inserted, in particular in the manner of a press-in bushing, into a corresponding opening along the longitudinal axis in the main valve housing part, whereby the position of the second valve seat in the longitudinal axis can be precisely adjusted. In particular, when inserting the insert bushing, if the stop is not formed on the insert bushing, the position of the second valve seat in the longitudinal axis, in particular relative to the stop, can be precisely adjusted.
[0027] A preferred development of the present invention provides that the second valve seat and / or the stop has or has at least one bypass channel. The respective bypass channel can preferably be designed in the manner of a groove or recess and allows a flow of the fluid, in particular when the second sealing surface rests against the second valve seat in the second position or when the stop portion rests against the stop.
[0028] According to a further development of the present invention, the valve housing comprises a main valve chamber. The main valve chamber is fluidically connected to the at least one inlet and the at least one outlet. A main valve slide, which is prestressed against a main valve seat by means of a main spring, can preferably be arranged in the main valve chamber. The pilot valve chamber is preferably fluidically connected to the main valve chamber by means of the second passage channel, whereby the fluid can flow from the inlet through the main valve chamber, inter alia via the second passage channel and the pilot valve chamber to the at least one outlet.
[0029] A further development of the present invention provides that the main slide is designed as a proportional slide. A further aspect of the present invention relates to a vibration damper with a pressure control valve as described above.
[0030] Three exemplary embodiments of a pressure control valve according to the invention are described in detail below with reference to the accompanying drawings. They show:
[0031] Figure 1 is a sectional view of a pressure control valve with an energizable actuating device, comprising a tappet and a pilot seal arranged on the tappet, wherein an actuating device is not energized and the pilot seal in a first position is sealingly in contact with a first valve seat in a pilot valve chamber,
[0032] Figure 2 is an enlarged detailed view of the pressure control valve according to Figure 1, wherein the actuating device is slightly energized and the pilot seal in this position rests against a stop in the pilot valve chamber,
[0033] Figure 3 is an enlarged detailed view of the pressure control valve according to Figure 1 or 2, wherein the actuating device is more strongly energized and pushes through the pilot seal in a second position such that the pilot seal bears sealingly against a second valve seat in the pilot chamber,
[0034] Figure 4 is an enlarged sectional view of a second embodiment of the pressure control valve in the de-energized state analogous to Figure 1, Figure 5 is an enlarged sectional view of a second embodiment of the pressure control valve according to Figure 4, wherein the actuating device is slightly energized as in Figure 2,
[0035] Figure 6 is an enlarged sectional view of a third embodiment in the de-energized state of the actuating device analogous to Figure 1,
[0036] Figure 7 is an enlarged sectional view of a third embodiment of the pressure control valve according to Figure 6, wherein the actuating device is slightly energized as in Figure 2,
[0037] Figure 8 is an enlarged sectional view of a fourth embodiment in the de-energized state of the actuating device analogous to Figure 1,
[0038] Figure 9 is an enlarged sectional view of a fourth embodiment of the pressure control valve according to Figure 8, wherein the actuating device is slightly energized as in Figure 2,
[0039] Figure 10 is an enlarged view of the pilot seal, and
[0040] Figure 11 is an enlarged view of a further development of the pilot seal according to Figure .
[0041] Identical or functionally equivalent parts or features are identified by the same reference numerals in the following detailed description of the figures. Likewise, not all identical or functionally equivalent parts or features are provided with a reference numeral in the figures.
[0042] First, a first exemplary embodiment is described in detail below with reference to Figures 1-3. The other exemplary embodiments are then briefly described, with only the differences from the previous exemplary embodiments being discussed. It should be noted at this point that the features of the exemplary embodiments and also of the further developments can be combined with one another.
[0043] Figure 1 shows a first exemplary embodiment of a pressure control valve 1 for controlling or regulating the pressure of a fluid. The pressure control valve 1 can be used, for example, in a vibration damper (not shown), in particular of a motor vehicle, to adjust a damping characteristic of the vibration damper.
[0044] The pressure control valve 1 comprises a valve housing 10 with at least one inlet and at least one outlet. The at least one inlet can be connected to a pilot pressure chamber.
[0045] The valve housing 10 at least partially encloses a pilot valve chamber 20, wherein a first valve seat 21 and a second valve seat 22 are arranged in the pilot valve chamber 20. The first valve seat 21 and the second valve seat 22 are arranged in the valve housing 10, or more precisely in the pilot valve chamber 20, on opposite sides along the longitudinal axis L. As can be seen in particular from the detailed illustrations according to Figures 2-9, the first valve seat 21 is arranged in a first wall section 30 and the second valve seat 22 is arranged in a second wall section 32.
[0046] The pilot valve chamber 20 is connected, inter alia, to the at least one outlet by means of a first passage channel 17. Furthermore, the pilot valve chamber 20 is connected to the at least one inlet by means of a second passage channel 18, whereby the fluid can flow through the at least one inlet and the second passage channel 18 into the pilot valve chamber 20 and can flow through the first passage channel 17 to the at least one outlet.
[0047] The first wall section 30 comprises the first passage channel 17, the first valve seat 21, and preferably a through-bore 19, which will be described in detail later. The second wall section 32 comprises the second passage channel 18 and the second valve seat 22.
[0048] The valve housing 10 can comprise a main housing part, a valve housing cover part 31 and / or an insert bushing 33. Preferably, the valve housing cover part 31 comprises the first wall section 30 and the insert bushing 33 comprises the second wall section 32.
[0049] Furthermore, it can be seen from Figures 2 to 5 that the valve housing 10 has a stop 15 arranged along the longitudinal axis L between the first valve seat 21 and the second valve seat 22 in the pilot valve chamber 20. The first valve seat 21 and the second valve seat 22 are preferably formed with the same diameter with respect to the longitudinal axis L.
[0050] Furthermore, it can be seen from Figure 1 that the valve housing 10 has a main valve chamber 50, which is fluidically connected on the one hand to the at least one inlet and on the other hand to the at least one outlet. According to the illustrated embodiment, a main valve slide 54 can be arranged in the main valve chamber 50, which is held preloaded against a main valve seat 51 by a main valve spring 55.
[0051] The main valve chamber 50 is fluidically arranged between the at least one inlet and the pilot valve chamber 40. This means that the fluid from the at least one inlet must first flow through the main valve chamber 50 before it can enter the pilot valve chamber 40 through the second passage 18. For this purpose, the main valve spool 54 has a passage 58, which is shown in Figure 1.
[0052] In addition, the pressure control valve 1 has an energizable actuating device 70, wherein the energizable actuating device 70 - as in the illustrated embodiment - can preferably be formed by an electromagnetic actuator.
[0053] The actuating device 70 can be accommodated in an actuator housing 71, wherein the actuating device 70 further comprises an excitation coil 72, an armature 73 and a return spring 75. The armature 73 can be moved along a longitudinal axis L when the excitation coil 72 is energized, counter to a spring force of the return spring 75 in a known manner. The actuator housing 71 has a receiving area into which the valve housing 10 can be at least partially inserted. The valve housing 10 can be fixedly arranged in the receiving area of the actuator housing 71, for example by a positive, non-positive and / or material connection.
[0054] Furthermore, the pressure control valve 1 has a plunger 60, wherein the plunger 60 can be moved along the longitudinal axis L by the actuating device 70. For this purpose, the plunger 60 is preferably connected to the armature 73 and can furthermore - as shown in Figure 1 - be held movably mounted on the actuator housing 71 along the longitudinal axis L by means of bearing elements 77.
[0055] The plunger 60 projects from the actuator housing 71 into the valve housing 10. In particular, as can be seen from the detailed illustrations of Figures 2 to 9, a first free end 61 of the plunger 60 projects into the pilot valve chamber 20.
[0056] Furthermore, it can be seen from the accompanying figures that the tappet 60 has a pressure equalization bore 65 through which the tappet 60 can be flowed along the longitudinal axis L. Consequently, the fluid can flow from the first free end 61 through the tappet 60 into a pressure equalization chamber 76 opposite the armature 73, whereby pressure equalization can take place and the pressure control valve 1 can be designed to be pressure-balanced.
[0057] The plunger 60 further comprises a pilot seal 40, which is fixedly arranged on the plunger 60, preferably adjacent to the free end 61. The pilot seal 40 can, for example, be attached to the plunger 60 by means of a retaining ring 68, as shown in the accompanying figures.
[0058] The pilot seal 40, according to the embodiments shown in Figures 1 to 5, is shown in detail in Figure 10 and comprises a disc element 43. The disc element 43 is preferably designed in the manner of a disc-shaped flat spring element.
[0059] The pilot seal 40 can essentially be described as an annular disc and has a sealing section 46, a spring section 47, and a stop section 48. The sealing section 46 and the stop section 48 are approximately annular, and the stop section 48 radially surrounds the sealing section 46. The sealing section 46 and the stop section 48 are connected by a spring section 48. The stop section 48 can thus be elastically displaced relative to the sealing section 46 along its longitudinal axis.
[0060] The sealing section 46 can be described as essentially annular and, according to Figures 2 to 9, comprises a first sealing surface 41 and a second sealing surface 42, which are arranged in the longitudinal axis L on opposite sides of the pilot seal 40.
[0061] Furthermore, it can be seen from Figure 10 that the pilot seal 40 has one or more flow-through openings 49 beyond the sealing section 46. The fluid can flow through the pilot seal 40 in the longitudinal axis through the at least one passage opening 49. Figure 11 shows a further development of the pilot seal 40 according to Figure 10. At least one, preferably two or more star-shaped spring sections 47 protrude from the sealing section 46, each of which has a stop section 48 at its free end. In this way, passage openings 49 are formed beyond the at least one web-shaped spring section 47 and / or stop section 48, which allow fluid communication between the two opposite sides of the pilot seal 40.
[0062] In an unactuated state of the actuating device 70 according to Figures 1, 4, 6 and 8, the pilot seal 40 is arranged in a first position A by means of the return spring 75. For the sake of clarity, the figures in which the actuating device 70 is unactuated are marked with "A". In the first position A, the first sealing surface 41 bears sealingly against the first valve seat 21 and closes the first passage channel 17.
[0063] In this first position A of the pilot seal 40, the fluid from the pilot valve chamber 20 cannot flow through the first passage 17 toward the at least one outlet. In other words, the pilot valve chamber 20 is closed on the outlet side in this first position A.
[0064] Figures 1, 4, 6 and 8 show the pilot seal 40 in the first position A, which corresponds to an undeformed state of the pilot seal 40. In the undeformed state of the pilot seal 40, a first distance A1 - measured along the longitudinal axis L - between the second sealing surface 42 and the second valve seat 22 is greater than a second distance A2 - also measured along the longitudinal axis L - between the stop section 48 and the stop 15, i.e. A1 > A2. In an actuated state of the actuating device 70, the excitation coil 72 of the actuating device 70 is slightly energized, for example by means of O.4A, and the pilot seal 40 is moved from the first valve seat 21 in the direction of the second valve seat 22 according to Figure 2. In the process, as shown in Figures 2, 5, 7 and 9, the stop section 48 comes to bear against the stop 15.
[0065] In this position of the pilot seal 40, the fluid can flow both from the pilot valve chamber 20 through the first passage channel 17 in the direction of the at least one outlet and from the at least one inlet through the second passage channel 18 into the pilot valve chamber 20. In the pilot valve chamber 20, the fluid flows through the pilot seal 40 in the embodiment according to Figures 1-7 through its at least one passage opening 49.
[0066] In a further actuated state of the actuating device 70, the excitation coil 73 of the actuating device 70 is energized more strongly and the pilot seal 40 is elastically deformed according to Figure 3. As a result, the sealing section 46 is displaced in the longitudinal axis L relative to the stop section 48 resting against the stop 15 in the direction of the second valve seat 22 and comes into contact with the second valve seat 22. In the second position B, the second sealing surface 42 bears sealingly against the second valve seat 22 and closes the second passage 18.
[0067] In this second position B of the pilot seal 40, the pilot seal 40 presses sealingly against the second valve seat 22 and prevents the fluid from the at least one inlet from flowing into the pilot valve chamber 20. The second embodiment according to Figures 4 and 5 differs from the previously described first embodiment in the design of the pilot seal 40. As can be seen from Figures 4 and 5, the pilot seal 40 comprises two sealing elements 44, 45 which are arranged on opposite sides of the disk element 43.
[0068] The two sealing elements 44, 45 can be made of a different material than the disc element 43, for example, to provide improved sealing properties. The two sealing elements 44, 45 are arranged in the sealing section 46 and form the respective sealing surfaces 41, 42 in the sealing section 46.
[0069] The disc element 43 and the two sealing elements 44 and 45 can be connected to one another or the disc element 43 and the two sealing elements 44 and 45 can be arranged loosely on one another on the tappet 60 and held there by means of the retaining ring 68 in a loss-proof manner.
[0070] In order for the fluid to flow through a pilot seal 40 designed in this way, at least one passage opening 49 is arranged radially beyond the sealing section 46 or the sealing elements 44, 45.
[0071] The third exemplary embodiment differs from the first exemplary embodiment in particular in the design of the second wall section 32. According to the third exemplary embodiment, the second wall section 32 comprises the stop 15 and the second valve seat 22. The stop 15 and the second valve seat 22 can be manufactured in a common machining step, whereby a high dimensional accuracy of the positions of the stop 15 and the valve seat 22 in the longitudinal axis L can be achieved. In other words, a distance between the stop 15 and the valve seat 22 can be manufactured with dimension accuracy.
[0072] The fourth embodiment according to Figures 8 and 9 differs in particular from the previously described third embodiment in the design of the pilot seal 40 and the stop 15.
[0073] The pilot seal 40 according to the fourth exemplary embodiment does not have any through-openings 49, but is designed as a continuous annular disk, comprising the sealing section 45, the spring section 46, and the stop section 47. In order to enable a flow to occur between the first valve seat and the second valve seat 22 in the pilot valve chamber 20, at least one bypass channel 16 designed in the manner of a groove is arranged in the stop 15. When the stop section 48 bears against the stop 15, the fluid can flow past the pilot seal 40 through the at least one bypass channel 16.
[0074] Furthermore, all of the previously described embodiments have in common that a failsafe seal 35 is arranged on the side of the first wall section 30 facing away from the pilot valve chamber 20. The failsafe seal 35 is held preloaded against the first wall section 30 and lies sealingly against a failsafe seat 36 with the passage bore 19.
[0075] The fail-safe seal 35 can be designed as a disc-shaped flat spring element and can further be arranged between the first wall section 30 and the actuator housing 71.
[0076] The preload of the failsafe seal 35 can be achieved by a failsafe spring 37.
[0077] Furthermore, it can be seen from Figures 1 to 9 that the fail-safe seat 36 can be formed by at least one annular projection. In the illustrated embodiments, the fail-safe seat 36 is formed by two projections arranged coaxially around the longitudinal axis L.
[0078] The passage bore 19 is arranged in the first wall section 30 such that the pilot seal 40 cannot form a sealing contact with the passage bore 19. In the event of a power failure or in the de-energized state of the actuating device 70, the fluid can flow from the pilot valve chamber 20 through the passage bore 19 to the at least one outlet, counter to the sealing effect of the fail-safe seal 35, thereby ensuring that, for example, the vehicle can continue to operate with a specific damping characteristic even in the event of a power failure.
[0079] List of reference symbols
[0080] 1 pressure control valve
[0081] 10 valve housings
[0082] 15 stops
[0083] 16 bypass channels
[0084] 17 first passage channel
[0085] 18 second passage channel
[0086] 19 Through hole
[0087] 20 Pilot valve chamber
[0088] 21 first valve seat
[0089] 22 second valve seat
[0090] 30 first wall section
[0091] 31 Valve housing cover part
[0092] 32 second wall section
[0093] 33 Insert bushing
[0094] 35 Fail-safe seal
[0095] 36 Failsafe seat
[0096] 37 Fail-safe spring
[0097] 40 Pilot seal attention
[0098] 41 first sealing surface
[0099] 42 second sealing surface
[0100] 43 Disc element
[0101] 44 Sealing element
[0102] 45 Sealing element
[0103] 46 Sealing section
[0104] 47 spring section
[0105] 48 stop section
[0106] 49 passage openings
[0107] 50 Main valve chamber
[0108] 51 Main valve seat 54 Main valve spool
[0109] 55 Mainspring
[0110] 60 pestles
[0111] 65 Pressure equalization hole
[0112] 68 Retaining ring
[0113] 70 Actuating device
[0114] 71 actuator housing
[0115] 72 Excitation coil
[0116] 73 anchors
[0117] 75 return spring
[0118] 76 Pressure equalization chamber
[0119] 77 Bearing element
[0120] L Longitudinal axis
[0121] Al first distance
[0122] A2 second distance
Claims
Patent claims 1. Pressure control valve (1) for controlling or regulating a pressure of a fluid in a pilot pressure chamber, comprising — a valve housing (10) with at least one inlet which is fluidically connectable to the pilot pressure chamber, and with at least one outlet, and a first valve seat (21) and a second valve seat (22) arranged between the at least one inlet and at least one outlet (20), — a plunger (60) with a pilot seal (40), wherein the plunger (60) is movable along a longitudinal axis (L) by means of an energizable actuating device (70), — wherein the pilot seal (40) has a sealing section (46) with a first sealing surface (41) and a second sealing surface (42) arranged on opposite sides in the longitudinal axis (L), — wherein, in an unactuated state of the actuating device (70), the pilot seal (40) is arranged in a first position (A) by means of a return spring (75), in which the first sealing surface (41) bears sealingly against the first valve seat (21) and closes a first passage channel (17), — wherein in the actuated state of the actuating device (70) the pilot seal (40) can be arranged in a second position (B), in which the second sealing surface (42) rests on the second valve seat (22) and closes the second passage channel (18), — wherein the pilot seal (40) has a stop section (48) which is spring-loaded relative to the sealing section (46) and which can come to rest against a stop (15) between the first end position (A) and a second end position (B) before the second end position (B) is reached.
2. Pressure control valve (1) according to claim 1, characterized in that in the first position (A) a first distance (Al) measured along the longitudinal axis (L) between the second sealing surface (42) and the second valve seat (22) is greater than a second distance (A2) measured along the longitudinal axis (L) between the stop section (48) and the stop (15).
3. Pressure control valve (1) according to claim 1 or 2, characterized in that the pilot seal (40) has at least one flow-through opening (49).
4. Pressure control valve (1) according to one of claims 1 to 3, characterized in that the pilot seal (40) has a spring portion (47).
5. Pressure control valve () according to one of the preceding claims, characterized in that the spring section (47) is arranged between the sealing section (46) and the stop section (48). Pressure control valve () according to one of the preceding claims, characterized in that the pilot seal comprises a disc-shaped flat spring element.
7. Pressure control valve (1) according to one of the preceding claims, characterized in that the pilot seal (40) comprises a sealing element (44, 45) comprising the first sealing surface (41) and / or the second sealing surface (42).
8. Pressure control valve (1) according to one of the preceding claims, characterized in that the pilot valve chamber (20) is formed in the valve housing (10), and that the first valve seat (21) and the second valve seat (22) are arranged on opposite sides of the pilot valve chamber (20).
9. Pressure control valve (1) according to one of the preceding claims, characterized in that the valve housing (10) comprises a first wall section (30) which has the first valve seat (21) and the passage channel (17).
10. Pressure control valve (1) according to one of the preceding claims, characterized in that the first wall section (30) has at least one passage bore (19) which forms a bypass around the first valve seat (21).
11. Pressure control valve (1) according to one of the preceding claims, characterized in that on the side of the first wall section (30) facing away from the first valve seat (21) there is arranged a fail-safe seal (35) which is prestressed against the first wall section (30) and can close the passage bore (19).
12. Pressure control valve (1) according to one of the preceding claims, characterized in that the wall section (30) is formed by a valve housing cover part (31).
13. Pressure control valve (1) according to one of the preceding claims, characterized in that the valve housing (10) has a second wall section (32) which comprises the second valve seat (22) and / or the stop (15).
14. Pressure control valve (1) according to one of the preceding claims, characterized in that the second valve seat (22) and / or the stop (15) have or has at least one bypass channel (16).
15. Pressure control valve (1) according to one of the preceding claims, characterized in that the second wall section (32) comprises an insert bushing (33).
16. Pressure control valve (1) according to one of the preceding claims, characterized in that the valve housing (10) comprises a main valve chamber (50) in which a main valve slide (54) is arranged, which is prestressed against a main valve seat (51) by means of a main valve spring (55).
17. Pressure control valve (1) according to one of the preceding claims, characterized in that the main valve slide (54) is designed as a proportional slide.
18. Vibration damper with a pressure control valve (1) according to one of the preceding claims.