Pressure regulating valve for controlling or regulating fluid pressure in pilot pressure chamber and vibration damper having such pressure regulating valve

Abstract

The invention relates to a pressure regulating valve for controlling or regulating a fluid pressure in a pilot pressure chamber, comprising: a valve housing having at least one inlet which can be fluidically connected to the pilot pressure chamber, at least one outlet, a main valve chamber which is arranged between the at least one inlet and the at least one outlet and has a main valve plate and a main valve seat, and a pilot valve chamber having a first valve seat and a pilot seal; and a tappet, which can be moved along the longitudinal axis by means of an energizable actuating device, and a pilot seal, which can be moved along the longitudinal axis between a first position, in which the pilot seal sealingly abuts against the first valve seat, and a second position, in which the pilot seal sealingly abuts against the second valve seat; the main valve plate is held biased against the main valve seat by a spring assembly formed hollow along the longitudinal axis; the spring assembly comprises a strong first spring section and a weak second spring section, and the first spring section and the second spring section are connected in series; and the second spring section is in effective contact with the main valve plate.

Description

Technical Field

[0001] The invention relates to a pressure regulating valve for controlling or regulating the pressure of a fluid in a pilot pressure chamber having the features of claim 1. Furthermore, the invention relates to a shock absorber having such a pressure regulating valve having the features of claim 18. Background Art

[0002] Pressure regulating valves of various designs are known from the prior art. For example, pressure regulating valves commonly used in the prior art are used in shock absorbers in motor vehicles, wherein the damping characteristics of the pressure regulating valve depend on the volume flow of the fluid used which flows through a proportional valve. Depending on the volume flow, a softer damping which emphasizes comfort or a harder damping which is more suitable for sports can be set. In shock absorbers, electrically energizable actuating devices are used, with which a plurality of damping characteristics can be specified by the driver or the damping characteristics can be adjusted automatically by an on-board computer depending on the driving state of the motor vehicle or on the state of the floor covering along which the motor vehicle is moving in a straight line.

[0003] The fluid can be hydraulic or pneumatic, wherein hydraulic liquid or compressed air is usually used. The pilot pressure chamber in the hydraulic or pneumatic operating device is used to control or adjust the pilot control valve, which is usually also implemented as a hydraulic or pneumatic valve plate. When the pilot control valve is designed as a proportional valve or proportional valve plate, the volume flow through the proportional valve or proportional valve plate can be adjusted steplessly within certain limits with the pressure in the pilot pressure chamber.

[0004] Such pressure control valves have proven themselves in the past, but it must always be ensured that in the event of a power failure and thus a failure of the actuation of the pressure control valve, a failsafe is provided. This ensures that the vehicle can continue to operate with a defined damping characteristic even in the event of a power failure. In this context, a medium damping characteristic is usually sought, which is neither too hard nor too soft.

[0005] These requirements lead to relatively complex structures of devices, in particular shock absorbers, as can be seen, for example, in US20160091044A1 and WO2016066314A1. The structure is complicated in particular because a plurality of valve plates must be used. Further shock absorbers are disclosed in US20160369862A1, JP2009115319A, US5147018A, WO2011023351A1 and US20050016086A1. In particular, the shock absorber disclosed in EP2678581B1 also provides moderate damping characteristics in the "fail safe" mode.

[0006] A disadvantage that has emerged in the pressure control valves known from the prior art is that in the lowest control range the control or regulation of the fluid pressure varies greatly, whereby the damping behavior can vary greatly, especially at low energization of the actuator. Summary of the invention

[0007] The present invention is proposed herein.

[0008] The present invention is directed to the object of proposing a universal pressure regulating valve which eliminates the disadvantages known from the prior art in a manner that is in line with the purpose. The proposed pressure regulating valve should be able to adjust the damping behavior in a reproducible manner even at low energization in the lowest adjustment range. Low sample deviations should also be achieved, which means that the characteristics of the pressure regulating valve are essentially the same in series production. As a further object, it can be mentioned that a pressure regulating valve is provided for regulating the fluid pressure in a pilot pressure chamber, which pressure regulating valve is of simple construction and regulates the pressure in the pilot pressure chamber to a determinable value even in the absence of electrical energy for energizing the actuator. In addition, the object on which one design of the present invention is based is to provide a device with which the fluid pressure in the pilot pressure chamber can be adjusted and which can be operated with such a pressure regulating valve.

[0009] This object is achieved by a pressure regulating valve having the features of claim 1 and a shock absorber having the features of claim 18 .

[0010] Further advantageous embodiments of the invention are specified in the dependent claims.

[0011] A universal pressure regulating valve for controlling or regulating the fluid pressure in a pilot pressure chamber having the features of claim 1 has a valve housing having at least one inlet and at least one outlet. The at least one inlet can be fluidically connected to the pilot pressure chamber. In addition, the valve housing has: a main valve chamber arranged between the at least one inlet and the at least one outlet, having a main valve plate and a main valve seat, and a pilot valve chamber having a first valve seat and a pilot seal. The pilot pressure chamber is preferably connected to at least one outlet by means of a first through-channel and to at least one inlet by means of a second through-channel. In addition, the pressure regulating valve according to the present invention has a tappet having a pilot seal preferably firmly arranged on the tappet, wherein the tappet can be moved along the longitudinal axis between a first position and a second position by means of an energizable actuating device. The main valve plate is held against the main valve seat in an offset manner by a spring assembly that is hollow along the longitudinal axis. According to the present invention, the spring assembly comprises a strong first spring section and a weak second spring section, which are connected in series, wherein the weak second spring section is in effective contact with the main valve plate.

[0012] The invention is based on the idea of ​​proposing a pressure regulating valve that achieves a comfortable damping behavior and a gentle opening behavior. Length tolerances are compensated by connecting two spring sections in series, wherein the offset of the weaker second spring section compensates for these length tolerances. As a result, the main valve plate can be opened at low pressures, and then only the first stronger spring section acts with a high error rate. The hollow spring assembly or preferably the hollow cylindrical spring assembly also enables a fluid connection between at least one inlet and at least one pilot valve chamber through the main valve chamber that is as trouble-free as possible.

[0013] One refinement of the invention provides that the first spring section and / or the second spring section are each formed by a helical spring, preferably a helical compression spring. Helical springs are cost-effective and reliable components and allow for a precise adjustment of the spring constant, whereby the damping behavior can be optimally adjusted. It is therefore preferred that the helical spring is arranged oriented along the longitudinal axis and has a first end region and an opposite second end region, wherein the helical spring is preferably held in position at least at one end region by a spindle.

[0014] According to a preferred embodiment or another aspect of the invention, the first spring section can be formed by a helical spring and the second spring section can include at least two freely protruding spring fingers. The free end of the spring finger can be deflected or displaced along the longitudinal axis during a preferably elastic deformation of the spring finger. The second spring section thus formed enables a particularly short design of the spring assembly, whereby the proposed pressure regulating valve can have a particularly compact construction. In addition, it is preferred that the at least two freely protruding spring fingers are arranged uniformly distributed on the circumference around the longitudinal axis.

[0015] Preferably, the second spring section is arranged radially in the first spring section when observing along the longitudinal axis. However, it should be noted that the second spring section can also be arranged radially outside the first spring section or on the same diameter as the first spring section when observing along the longitudinal axis.

[0016] According to an improved solution of the present invention, it may be advantageous to provide a stop section between the first spring section and the second spring section, which stop section abuts against the main valve plate between the first spring section and the main valve plate, for example at the stop portion, in the compressed state of the second spring section. Alternatively, the stop section may abut against the valve housing between the first spring section and the valve housing, for example at the stop portion, in the compressed state of the second spring section. In this design, the second spring element is in effective contact with the valve housing. The stop section is preferably held by the second spring section in an elastic manner spaced apart from the stop portion in an unloaded state, wherein the distance between the stop section and the stop portion specifies the maximum spring travel of the second spring section.

[0017] Furthermore, it has proven to be advantageous if the second spring element comprises a second spring section and a stop section and if at least two independent spring fingers protrude freely from the stop section. The stop section can preferably be annular or toroidal, wherein the spring fingers protrude radially and / or in the circumferential direction preferably inwards from the stop section. The second spring element is in particular of one-piece design and can be produced, for example, as a stamped part.

[0018] A refinement of the present invention provides that the stop section is formed by a spring retainer, wherein the spring retainer has a toroidal shape with a Z-shaped cross section. The spring retainer can be configured as a separate component and can couple or connect the opposite ends of the first spring section and the second spring section to each other.

[0019] Furthermore, it has proven advantageous that the spring holder is at least partially pot-shaped and at least partially receives the first spring section and / or the second spring section in a pot-shaped manner. Thus, the weak second spring section can be at least partially arranged radially within the strong first spring section, thereby achieving a particularly compact design.

[0020] A refinement of the invention provides that at least one centering device is provided, by which the first spring section or the second spring section is held in position. In particular, it is preferred that the first spring section is held in position by at least one first centering device, and the second spring section is held in position by at least one second centering device, in particular relative to the longitudinal axis. The at least one first centering device can be realized, for example, as already mentioned, by a mandrel, which protrudes into the first spring section. The at least one first centering device can preferably be formed on the valve housing. The at least one second centering device can preferably interact with the main valve plate and hold the second spring section in position on the main valve plate.

[0021] In particular, according to a development, it is preferred that at least one centering means, in particular at least one second centering means, engages in a recess which is arranged around the through-channel in the valve housing or the channel in the main valve plate between the main valve chamber and the pilot valve chamber.

[0022] A preferred improvement of the invention provides that at least one centering device comprises at least two centering fingers, which are designed to protrude freely. In particular, it is preferred that at least two centering fingers are arranged on the second spring element and protrude freely from the second spring section and / or from the stop section. The centering finger can be arranged at an angle to the stop section and / or the spring section, whereby the centering finger can be brought into effective contact with the valve housing or the main valve plate in a simple manner for the centering arrangement of the second spring element. In the case of a centering finger protruding from the stop section, it can be advantageous if the centering finger is arranged between at least two spring fingers.

[0023] In addition, it has proven to be advantageous that a first valve seat and a second valve seat are arranged oppositely along the longitudinal axis in the pilot valve chamber. The pilot seal can be sealingly abutted against the first valve seat at a first position and sealingly abutted against the second valve seat at a second position. The pilot seal preferably has a first sealing surface and a second sealing surface, which are arranged on opposite sides along the longitudinal axis. The first sealing surface is configured to interact with the first valve seat, and the second sealing surface is configured to interact with the second valve seat.

[0024] According to another preferred design, the pilot valve chamber is arranged in the valve housing, wherein preferably, the pilot valve chamber is surrounded by the valve housing. In the pilot valve chamber, a first valve seat and a second valve seat are arranged on opposite sides of the valve housing along the longitudinal axis, wherein the first valve seat surrounds or surrounds the opening of a first through-channel that connects the pilot valve chamber with at least one outlet, and the second valve seat surrounds or surrounds the opening of a second through-channel that connects the pilot valve chamber with at least one inlet.

[0025] It has also proven to be advantageous if the valve housing comprises a wall section having a first valve seat and a first through-channel. The wall section can be designed according to the type of valve housing and preferably closes the pilot valve chamber on one side along the longitudinal axis, thereby resulting in an advantageous structure of the valve housing.

[0026] Furthermore, it has proven to be advantageous if the wall section has at least one through-hole which forms a bypass around the first valve seat. The bypass enables a fluid connection between the pilot valve chamber and the side of the wall section facing away from the pilot valve chamber both in the first position of the tappet and in the second position of the tappet, and 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 sealingly abutting the first valve seat.

[0027] In addition, it has proven to be advantageous if a failsafe seal offset against the wall segment is arranged on the side of the wall segment facing away from the first valve seat, which failsafe seal can be arranged against the wall segment in such a way that the through-hole is closed. The failsafe seal offset against the wall segment can specify a pressure in the pilot valve chamber at which the through-hole is released and fluid can flow from the pilot valve chamber through the through-hole to at least one outlet. The through-hole and the failsafe seal interacting with the through-hole ensure that the shock absorber can continue to operate with certain damping characteristics even in the event of an electrical energy failure. By selecting the offset of the failsafe seal, it can be defined, wherein the damping characteristics are generally selected in such a way that they are neither too hard nor too soft.

[0028] An advantageous development of the invention provides that the wall section is formed by a valve housing cover part. The valve housing cover part can be designed, for example, as a disk-shaped component and, together with the main valve housing part, surrounds the pilot valve chamber at least in regions.

[0029] A further development of the invention provides that the valve housing comprises a second wall section which comprises a second valve seat. Furthermore, the second wall section may also comprise a second through-channel, wherein the second through-channel is preferably designed as a hole. The second wall section is preferably arranged along the longitudinal axis on a side of the valve housing opposite to the first wall section, wherein the second wall section may be designed integrally with the main valve housing part.

[0030] A further development of the invention provides that the second wall section comprises an insert bushing which can be inserted along the longitudinal axis into a corresponding opening in a main valve housing part, for example an opening of a sleeve-shaped mandrel, in particular depending on the type of press-in bushing, so that the position of the second valve seat along the longitudinal axis can be precisely adjusted.

[0031] Another aspect of the present invention relates to a shock absorber having the aforementioned pressure regulating valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Hereinafter, five exemplary embodiments of the pressure regulating valve according to the present invention will be described in detail with reference to the accompanying drawings. In the accompanying drawings:

[0033] Figure 1 A cross-sectional view of a pressure regulating valve with an energizable actuation device, the pressure regulating valve having a main valve plate, a tappet, and a pilot seal arranged on the tappet, the main valve plate being biased against a main valve seat in a main valve chamber by a spring assembly having a first spring section and a second spring section, wherein the actuation device is energized and the pilot seal sealingly abuts against a first valve seat in the pilot valve chamber in a first position;

[0034] Figure 2 shows a detailed view of the spring element forming the second spring section;

[0035] Figure 3 shows a cross-sectional view of a second embodiment of a pressure regulating valve, wherein the actuating device is not energized,

[0036] Figure 4 Shown according to Figure 3 A detailed view of a second spring section of a pressure regulating valve;

[0037] Figure 5 shows a cross-sectional view of a third embodiment of a pressure regulating valve, wherein the actuating device is de-energized;

[0038] Figure 6 Shown according to Figure 5A detailed view of a second spring section of a pressure regulating valve;

[0039] Figure 7 shows a cross-sectional view of a fourth embodiment of a pressure regulating valve, wherein the actuating device is not energized,

[0040] Figure 8 Shown according to Figure 7 a detailed view of a second spring section of a pressure regulating valve; and

[0041] Fig. 9 A cross-sectional view of a fifth embodiment of a pressure regulating valve is shown, wherein the actuating device is de-energized. DETAILED DESCRIPTION

[0042] In the detailed description of the following drawings, identical or functionally identical components or features are identified by the same reference numerals. In addition, not all identical or functionally identical components or features are provided with reference numerals in the drawings.

[0043] First, refer to Figure 1 A first exemplary embodiment is described in detail. Subsequently, further embodiments are briefly described, wherein only the differences with the previous embodiments are discussed. At this point, it has been noted that the features of the embodiments as well as the developments can be combined with one another.

[0044] Figure 1 A first exemplary embodiment of a pressure regulating valve 1 for controlling or regulating the pressure of a fluid is shown. The pressure regulating valve 1 can be used, for example, in a shock absorber (not shown), in particular a shock absorber of a motor vehicle, to adjust the damping characteristics of the shock absorber.

[0045] The pressure regulating valve 1 comprises a valve housing 10 having at least one inlet and at least one outlet. The at least one inlet can be connected to a pilot pressure chamber.

[0046] The valve housing 10 at least partially surrounds a main valve chamber 50 and a pilot valve chamber 20 , which are arranged spaced apart from one another along the longitudinal axis L. A main valve seat 51 is formed in the main valve chamber 50 and a main valve plate 54 is arranged.

[0047] 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 on opposite sides along the longitudinal axis L in the valve housing 10 or more precisely in the pilot valve chamber 20.

[0048] The valve housing 10 comprises a first wall section 31, a second wall section 32 and a third wall section 33. The second wall section 32 is arranged between the first wall section 31 and the third wall section 33 along the longitudinal axis l.

[0049] The first wall section 31 comprises the first through-channel 11, the first valve seat 21 and preferably the through-hole 19 described in detail later. The second wall section 32 comprises the second through-channel 12 and the second valve seat 22, wherein the first wall section 31 and the second wall section 32 preferably delimit the pilot valve chamber 20 along the longitudinal axis L.

[0050] The second wall section 32 can include a sleeve section, into which a mandrel 34 an insert bushing 38 is inserted or pressed, which preferably has a second through-channel 12 and a second valve seat 22. When the insert bushing 38 is pressed in, the position of the second valve seat 22 in the valve housing 10 along the longitudinal axis L is precisely adjusted.

[0051] The third wall section 33 includes a main valve seat 51 and preferably delimits a main valve chamber 50 together with the second wall section 32 .

[0052] The main valve plate 54 is held movably along the longitudinal axis L in the valve housing 10 or in the main valve chamber 50 and is held by the spring assembly 60 biased against the main valve seat 51 in a closed position. In the closed position, the main valve plate 54 seals against the main valve seat 51. Here, the main valve plate 54 is preferably guided along the longitudinal axis L by the valve housing 10. For this purpose, the inner jacket surface of the valve housing 10, which also surrounds the main valve chamber 50, can be adapted to the outer jacket surface of the main valve plate 54 so that the main valve plate 54 can be easily guided linearly along the longitudinal axis L.

[0053] The main valve plate 54 preferably has a through opening 56 coaxially with the longitudinal axis L, through which a fluid can flow from the at least one inlet to the pilot valve chamber 20 .

[0054] On the side of the main valve plate 54 facing the pilot valve chamber 20 , a recess 55 can be formed around the through-opening 56 , which recess 55 allows an expansion of the flow-through cross section.

[0055] Especially from the basis Figure 1 , Figure 3 , Figure 5 , Figure 7 and Fig. 9 It can be seen in the detailed view of that the main valve seat 51 is arranged in the third wall section 33 which closes the main valve chamber 50 along the longitudinal axis L in the direction of the inlet or pilot pressure chamber in the manner of a cover.

[0056] The valve housing 10 , or more precisely the third wall section 33 , can have a breakthrough which is preferably arranged coaxially to the main valve plate 54 and which can form at least one inlet of the pressure regulating valve 1 .

[0057] The spring assembly 60 is hollow along the longitudinal axis L and may be described as being substantially hollow cylindrical.

[0058] The spring assembly 60 includes a strong first spring section 61 and a weak second spring section 62 , and the first spring section 61 and the second spring section 62 are connected in series.

[0059] The strong first spring section 61 and the weak second spring section 62 can be understood as the spring coefficient of the first spring section 61 being greater than the spring coefficient of the second spring section 62, wherein preferably, the ratio is at least 2:1, preferably 5:1, more preferably at least 10:1, and more preferably at least 20:1. The spring travel of the first spring section 61 is also greater than the spring travel of the second spring section, wherein the ratio is at least 2:1, preferably 5:1, more preferably at least 10:1, and more preferably at least 20:1.

[0060] Viewed along the longitudinal axis L, the first spring section 61 is arranged within the second spring section 62 , so that the cross section through which the spring assembly 60 flows is as large as possible.

[0061] The first spring portion 61 has a first end region and a second end region, wherein the first end region is supported on the valve housing 10 .

[0062] The second spring section 62 has a first end region and a second end region, wherein the second end region is supported on the main valve plate 54. Therefore, the second spring section 62 is in operative contact with the main valve plate 54.

[0063] A second end region of the first spring section 61 is coupled to a first end section of the second spring section 62 .

[0064] According to the illustrated and exemplary embodiment, the first spring section 61 can be formed by a first spring element 63 which is preferably designed as a helical spring, in particular a helical compression spring.

[0065] In addition, from Figure 1 , Figure 3 , Figure 5 , Figure 7 and Fig. 9 It can be seen that a locking section 65 is arranged between the first spring section 61 and the second spring section 62 , and the first spring section 61 is coupled to the second spring section 62 via the locking section 65 .

[0066] The second spring section 62 and the stop section 65 arranged between the first spring section and the second spring section 62 are the subject of different embodiments and will be described in more detail further below, wherein the function is identical.

[0067] The weak second spring section 62 has a very low spring constant, for example <1 N / mm, preferably <0.5-0.3 N / mm, whereby the main valve plate 54 is slightly offset. This achieves a gentle opening behavior of the pressure regulating valve 1. Length tolerances are compensated by the series connection of the two spring sections 61, 62, because the offset of the weak second spring section compensates for these length tolerances.

[0068] As soon as a slight pressure is applied to the main valve plate 54 via at least one inlet, the main valve plate 54 moves along the longitudinal axis L in the direction of the pilot valve chamber 20 until the maximum spring travel of the second spring section 62 is reached and the stop section 65 abuts against the main valve plate 54. Thereafter, further displacement of the main valve plate 54 along the longitudinal axis L can only be achieved by overcoming the spring force of the first spring section 61.

[0069] The pilot valve chamber 20 is connected to at least one outlet, in particular, by means of the first through-channel 11. In addition, the pilot valve chamber 20 is connected to at least one inlet via the second through-channel 12 through the main valve chamber 50, whereby the fluid can flow into the pilot valve chamber 20 via the at least one inlet and the second through-channel 12 and flow out to at least one outlet via the first through-channel 11.

[0070] Therefore, before the fluid can enter the pilot valve chamber 20, it must first flow from at least one inlet through the main valve chamber 50, the through-opening 56 of the main valve plate 54 and through the second through-channel 12. Here, it can be advantageous if the opening 15 of the second through-channel 12 leading to the main valve chamber 50 is arranged in a plane that is offset transversely to the longitudinal axis L relative to the through-opening 56 of the main valve plate 54.

[0071] Furthermore, the pressure regulating valve 1 has an energizable actuating device 80 , wherein, as in the exemplary embodiment shown, the energizable actuating device 80 can preferably be formed by an electromagnetic actuator.

[0072] The actuator 80 can be accommodated in an actuator housing 81, wherein the actuator 80 further includes an excitation coil 82, an armature 83 and a return spring 85. The armature 83 can move along the longitudinal axis L against the spring force of the return spring 85 when the excitation coil 82 is energized in a known manner.

[0073] The actuator housing 81 has a receiving area into which the valve housing 10 can be at least partially inserted. The valve housing 10 can be securely arranged in the receiving area of ​​the actuator housing 81, for example by a form-fitting, force-fitting and / or material-fitting connection.

[0074] Furthermore, the pressure regulating valve 1 has a tappet 70 , wherein the tappet 70 can be moved by an actuating device 80 along the longitudinal axis L. For this purpose, the tappet 70 is preferably connected to an armature 83 and can also be supported displaceably along the longitudinal axis L on an actuator housing 81 by means of a bearing element 87 .

[0075] The tappet 70 protrudes from the actuator housing 81 into the valve housing 10. In particular, Figures 2 to 9 It can be seen from the detailed view of FIG. 7 that the first free end of the tappet 70 protrudes into the pilot valve chamber 20 .

[0076] Furthermore, it can be seen from the figures that the tappet 70 has a pressure compensation hole 75 through which the tappet 70 can pass along the longitudinal axis L. As a result, the fluid can flow from the first free end through the tappet 70 to the pressure compensation chamber 86 opposite the armature 83 (see FIG. Fig. 9 ), thereby enabling pressure compensation, and the pressure regulating valve 1 can be constructed in a pressure-compensated manner.

[0077] The tappet 70 also has a pilot seal 40, which is preferably arranged firmly adjacent to the free end on the tappet 70. The pilot seal 40 can be firmly fastened to the tappet 70 by means of a pilot seal securing device 42, for example, as shown in the figures.

[0078] The pilot seal 40 may be generally described as an annular disk having a first sealing surface and a second sealing surface, wherein the first sealing surface and the second sealing surface are arranged on opposite sides along the longitudinal axis L. As shown in FIG.

[0079] In accordance with Figure 1 In the actuated state of the actuating device 80, the pilot seal 40 is arranged at the second position, and the pilot seal 40 sealingly abuts against the second valve seat 22 and closes the second through-channel 12. Figure 1 In the example, the second position is indicated by "B".

[0080] In accordance with Figure 3 , Figure 5 , Figure 7 and Fig. 9 In the non-actuated state of the actuating device 80, the pilot seal 40 is arranged at a first position, which is indicated by "A" in the figure, by means of a return spring 85. In the first position, the pilot seal 40 seals against the first valve seat 21 and closes the first through-channel 11.

[0081] In the first position A of the pilot seal 40, the fluid from the pilot valve chamber 20 cannot flow in the direction of the at least one outlet through the first through-channel 11. In other words, the pilot valve chamber 20 is closed on the outlet side in this first position A.

[0082] In the second position B of the pilot seal 40, the fluid cannot flow from the at least one inlet into the pilot valve chamber 20 through the second through-channel 12. In other words, the pilot valve chamber 20 is closed on the inlet side in this first position A.

[0083] In the adjustment operation, the pilot seal 40 is located between the first position A and the second position B, more precisely depending on the current intensity applied to the actuating device. The position of the pilot seal 40 results from the force balance of the actuating device 80, the return spring force of the return spring 85, the fluid compression force and the spring force of the first spring section 61.

[0084] The position of the pilot seal 40 in regulating operation allows flow through the pilot valve chamber 20 and thus pressure regulation of the pressure in the pilot valve chamber and the main valve chamber 50. As a result, the opening behavior of the main valve plate 54 and thus the damping behavior of the shock absorber can be adjusted.

[0085] Furthermore, a failsafe seal 35 can be arranged on the side of the first wall section 31 facing away from the pilot valve chamber 20 , which failsafe seal 35 is held offset against the first wall section 31 and in this case seals against a failsafe seat 36 of the through-opening 19 .

[0086] The failsafe seal 35 can be designed as a disk-shaped leaf spring element and can furthermore be arranged between the first wall section 31 and the actuator housing 81 .

[0087] The biasing of the failsafe seal 35 may be achieved by a failsafe spring 37 .

[0088] In addition, from the attached Figure 1 , Figure 3 , Figure 5 , Figure 7 and Fig. 9 It can be seen that the fail-safe seat 36 can be formed by at least one annular protrusion. In the embodiment shown, the fail-safe seat 36 is formed by two protrusions coaxially formed around the longitudinal axis L.

[0089] The through-hole 19 is arranged in the first wall section 31 in such a way that the pilot seal 40 cannot bear sealingly against the through-hole 19. In the event of an electrical power failure or in the de-energized state of the actuating device 80, the fluid can flow from the pilot valve chamber 20 through the through-hole 19 to at least one outlet against the sealing effect of the fail-safe seal 35, thereby ensuring that, for example, the vehicle can continue to operate with defined damping characteristics even in the event of an electrical power failure.

[0090] As already described above in conjunction with the first spring section 61, the first spring element 63 has a first end section and a second end section, wherein the first end section is supported on the valve housing 10. According to the exemplary embodiment shown, the valve housing 10, more precisely the second wall section 32, has a mandrel 34 designed as a sleeve section, which protrudes in the direction of the main valve plate 54 along the longitudinal axis L and rests on the first end section. As a result, the position of the first spring element 63 can be specified.

[0091] according to Figures 1 to 8 In the first four exemplary embodiments shown, the second spring section 62 can be formed by at least two protruding spring fingers 66 , which are arranged evenly distributed on the circumference.

[0092] The second spring section 62 can be formed by a second spring element 64, which is preferably in one piece. According to the first four embodiments, the second spring element 64 can include at least one, preferably at least two freely protruding spring fingers 66 and a stop section 65. The stop section 65 can have a complete or full-surface rest surface for the first spring element 63 on the circumference.

[0093] The respective freely protruding spring finger 66 has a free end 67, wherein the free end 67 of the spring finger 66 forms the second end region of the second spring section 62. The free end of the respective freely protruding spring finger 66 can preferably flatly abut the main valve plate 54 in an angled region to form an effective contact. Here, it is further preferred that the free end of the respective freely protruding spring finger 66 abuts the main valve plate 54 radially outside the through-opening 56 and / or the recess 55.

[0094] The stop section 65 can be described as being annular or ring-disk-shaped, with the freely protruding spring finger 66 being arranged radially inside.

[0095] The second spring element 64 can be made, for example, as a thin stamping, wherein the spring fingers 66 are formed according to Figure 2 b. Figure 3 , Figure 4 b is deflected from the plane of the stop section 65 .

[0096] An air gap can be provided between the locking section 65 and the respective spring finger 66 , wherein the air gap can have an expansion at the end, by which the notch effect between the locking section 65 and the second spring section 62 or the spring finger 66 can be reduced.

[0097] according to Figure 1 and Figure 2 The first embodiment and according to Figure 3 and Figure 4The second exemplary embodiment differs only in the design of the second spring element 64 .

[0098] The second spring element 64 can be adjusted according to Figures 3 to 8 The illustrated embodiments 2, 3 and 4 have at least one centering means. The at least one centering means can be designed as a centering finger 68. The respective spring finger 66 can include a centering finger 68 which protrudes freely from the respective spring finger 66, in particular at its free end 67.

[0099] like Figure 3 and Figure 4 As shown in FIG. 2 b , the spring finger 66 may be angled relative to a free end 67 of the spring finger 66 and may engage into the recess 55 of the main valve plate 54 to position the second spring element 64 .

[0100] The third embodiment Figure 5 and Figure 6 The third embodiment differs from the first and second embodiments only in the design of the centering means of the second spring element 64, wherein the second spring element 64 has three centering fingers 68, which protrude radially inward from the stop section 65. The centering fingers 68 are preferably arranged between the spring fingers 66 at the stop section 65 in the circumferential direction.

[0101] At this point it should be noted that Figure 6 The centering finger 68 is not (yet) Figure 5 As shown, the spring finger 66 is angled on the side facing away from the spring finger 66 along the longitudinal axis L. Figure 5 As shown, the centering finger 68 projects from the stop section 65 along the longitudinal axis L on the side facing the first spring element 63 and abuts against the inner side of the second end region of the first spring element 63 , whereby the second spring element 64 remains positioned on the first spring element 63 .

[0102] according to Figure 7 and Figure 8 In the fourth exemplary embodiment shown, the second spring portion 62 or the second spring element 64 is positioned on the outer side of the collar 58 formed on the main valve plate 54 .

[0103] The flange 58 can be arranged coaxially with the longitudinal axis L around the through opening 56 on the side of the main valve plate 54 facing the pilot valve chamber 20 and protrude in a hollow cylindrical shape in the direction of the pilot valve chamber 20 .

[0104] In order to keep the second spring element 64 in position, a preferably arcuate or semicircular centering finger 68 can be arranged on the respective spring finger 66 , which centering finger 68 projects inwardly and abuts against the outer jacket surface of the flange 58 .

[0105] The fifth embodiment differs from the above four embodiments in the designs of the stop section 65 and the second spring section 62 .

[0106] from Fig. 9 As can be seen in the figure, in the fifth embodiment, the second spring section 62 can be formed by a second elastic element 64 configured as a helical spring, in particular a helical compression spring, which is arranged coaxially with the first elastic element 63 configured as a helical spring, in particular a helical compression spring, along the longitudinal axis L. The second spring element 64 has an outer diameter that is smaller than the inner diameter of the first spring element 61.

[0107] The stop section 65 is formed by a spring holder 69, wherein the spring holder 69 has a toroidal shape with a Z-shaped cross section. The spring holder 69 may be configured as a separate component and may couple or connect opposite ends of the first spring element 63 and the second spring element 64 to each other.

[0108] The spring holder 69 can be described as being of segmented pot-shaped design, and on the one hand, the first spring section 61 or the second end section of the first spring element 63 can be inserted into the spring holder 69, and on the other hand, the second spring section 62 or the first end section of the second spring element 64 can be inserted into the spring holder 69. Therefore, the second spring element 64 is at least partially arranged radially in the first spring element 63 along the longitudinal axis L. As a result, a compact design is also achieved in this embodiment.

[0109] According to a not shown refinement, the second spring element 64 can have an inner diameter that is greater than the outer diameter of the first spring element 61. In this design, the second spring element 64 can be arranged radially along the longitudinal axis L at least partially outside around the first spring element 63.

[0110] from Fig. 9 It can further be seen in FIG. 5 that the main valve plate 54 can have the collar 58 mentioned in the other case above, by which the second spring element 64 is held in position on the main valve plate 54 .

[0111] Description of reference numerals:

[0112] 1 Pressure regulating valve

[0113] 10 valve housing

[0114] 11 First through-passage

[0115] 12 Second through passage

[0116] 15 Opening

[0117] 19 Through hole

[0118] 20 Pilot valve chamber

[0119] 21 First valve seat

[0120] 22 Second valve seat

[0121] 31 First wall segment

[0122] 32 Second wall segment

[0123] 33 Third wall segment

[0124] 34 Spindle

[0125] 35 Failsafe Seals

[0126] 36 Failsafe Seat

[0127] 37 Fail safe spring

[0128] 38 Insert bushing

[0129] 40 Pilot seal

[0130] 42 Pilot seal safety device

[0131] 50 Main valve chamber

[0132] 51 Main valve seat

[0133] 54 Main valve plate

[0134] 55 recess

[0135] 56 Through opening

[0136] 58 Flange

[0137] 60 Spring assembly

[0138] 61 First spring section

[0139] 62 Second spring section

[0140] 63 First spring element

[0141] 64 Second spring element

[0142] 65 Stop section

[0143] 66 Spring fingers

[0144] 67 66 free end

[0145] 68 Centering finger

[0146] 69 Spring retainer

[0147] 70 Tappet

[0148] 75 Pressure compensation hole

[0149] 80 Actuator

[0150] 81 Actuator housing

[0151] 82 Excitation coil

[0152] 84 Armature

[0153] 85 Return spring

[0154] 86 Pressure compensation chamber

[0155] 87 Support element

[0156] L Longitudinal axis

Claims

1. A pressure regulating valve (1) for controlling or regulating the pressure of a fluid in a pilot pressure chamber, comprising: - a valve housing (10), the valve housing (10) comprising: at least one inlet fluidically connectable to the pilot pressure chamber, at least one outlet, a main valve chamber (50) arranged between the at least one inlet and the at least one outlet and comprising a main valve plate (54) and a main valve seat (51), and a pilot valve chamber (20) comprising a first valve seat (21) and a pilot seal (40); and a tappet (70) movable along a longitudinal axis (L) by means of an energizable actuating device (80), and wherein the pilot seal (40) is movable along the longitudinal axis (L) between a first position in which the pilot seal (40) sealingly abuts against the first valve seat (21) and a second position; - wherein the main valve plate (54) is biased against the main valve seat (51) by a spring assembly (60) which is hollow along the longitudinal axis (L); - wherein the spring assembly (60) comprises a strong first spring section (61) and a weak second spring section (62), and the strong first spring section (61) and the weak second spring section (62) are connected in series; The invention is characterized in that the second spring section (62) is in effective contact with the main valve plate (54).

2. The pressure regulating valve (1) according to the preceding claim, characterized in that The first spring section (61) and / or the second spring section (62) are each formed by a spring element (63, 64) designed as a helical spring.

3. The pressure regulating valve (1) according to any of the preceding claims or according to the preamble of claim 1, characterized in that The first spring section (61) comprises a first spring element (63) designed as a helical spring, and the second spring section (62) comprises at least two, preferably three freely protruding spring fingers (66).

4. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that A stop section (65) is arranged between the first spring section (61) and the second spring section (62), and the stop section (65) abuts against the valve housing (10) or the main valve plate (54) in the compressed state of the second spring section (62).

5. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The second spring element (64) comprises the second spring section (62) and the stop section (63).

6. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The stop section (63) is formed by a spring retainer (69) having a toroidal shape with a Z-shaped cross section.

7. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The spring holder (69) at least partially holds the first spring section (61) and / or the second spring section (62) in a pot-shaped manner.

8. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that At least one centering means is provided, which holds the first spring section (61) and / or the second spring section (62) in position.

9. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The at least one centering means engages in a recess (55) and / or a collar (58) which are arranged around a through opening (56) in the main valve plate (54).

10. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The at least one centering means comprises at least two centering fingers (68) which are designed to protrude freely.

11. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The pilot valve chamber (20) is formed in the valve housing (10), and the first valve seat (21) and the second valve seat (22) are arranged on opposite sides of the pilot valve chamber (20).

12. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The valve housing (10) comprises a first wall section (31) having the first valve seat (21) and a first through-channel (11) connecting the pilot valve chamber (20) to the at least one outlet.

13. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The wall section (31) has at least one through-hole (19), which forms a bypass around the first valve seat (21).

14. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that A fail-safe seal (35) is arranged on a side of the first wall section (31) facing away from the first valve seat (21) and is biased against the first wall section (31), wherein the fail-safe seal (35) can close the through-hole (19).

15. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The valve housing (10) has a second wall section (32) which includes the second valve seat (22).

16. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The second wall section (32) includes an insert bushing (38).

17. The pressure regulating valve (1) according to any one of the preceding claims, characterized in that The actuating device (80) is pressure-compensated.

18. A shock absorber having a pressure regulating valve (1) according to any one of the preceding claims.

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