Damping valve device with pre-stage and main stage valve

Abstract

A damping valve device comprising an electromagnetic actuator having a valve armature for operating a pre-stage valve body in a pre-stage valve, wherein the pre-stage valve operates a main-stage valve of the damping valve device and both valves are embodied as sequence valves, wherein the damping valve device has an emergency operating device having an emergency operating armature and a tension spring which pre-tensions the emergency operating armature in the direction of the main-stage valve, wherein a stop limits the axial adjustment travel of the pre-stage valve body, wherein the stop is formed by a stop spring which is functionally embodied between the emergency operating armature and the pre-stage valve.

Description

Technical Field

[0001] This invention relates to a damping valve device having a pre-stage valve and a main-stage valve. Background Technology

[0002] A damping valve device is known from DE 10 2016 221 896 A1, which includes a forestage valve and a main stage valve. The forestage valve is implemented as a reversing sequence valve (Weg-Folgeventil). The reversing sequence valve is characterized by the synchronous operative movement of the two valve elements.

[0003] In DE 10 2016 221 896 A1, the main valve body has a seat surface on the back side, which, together with the pre-stage valve body, constitutes the pre-stage valve. In the case of a sequential valve, the actuator's valve armature may have to perform a very large adjustment stroke to achieve a sufficiently large outflow cross-section at the pre-stage valve. Especially when gentle damping force adjustment is combined with a sudden, extreme lifting force on the main valve body, the pre-stage valve body and thus the valve armature can perform a very large adjustment stroke. This large adjustment stroke may lead to increased resistance to the actuator's magnetic flux due to minimal axial overlap between the subsequent valve armature and the magnetic pole plate.

[0004] In contrast, for example, EP 0 499 183 A1 discloses a damping valve device in which the forestage valve has an axially movable forestage valve body and a valve seat face fixed by the housing position. The main stage valve includes a main stage valve body that cannot apply an opening force to the forestage valve body in any operating state.

[0005] Because the reduced magnetic flux may not reach the activation threshold of the emergency operation armature, the damping valve device will still enter emergency operation even with sufficient external power supply.

[0006] When the power supply is intact, a so-called push-strom current can be introduced into the solenoid coil of the damping valve device at regular intervals to switch the emergency operating armature, which has entered the emergency operating position, back to the normal operating position. However, this regulating current may result in inappropriately drastic damping force adjustments during momentary travel, which can be felt even by less sensitive occupants.

[0007] Alternatively, the axial displacement of the valve armature can be limited to ensure sufficient magnetic flux at all times. In the example according to DE 102016 221 896 A1, the central tubular shaft forms the aforementioned stop with its end face and the bottom of the armature guide.

[0008] However, the result of this stroke-dependent stop for the valve armature is that, since the upstream valve body is held in place by the stop, the closing motion of the upstream valve begins in an uncontrolled manner, which means, for example, undesirable high damping force regulation.

[0009] Another characteristic of the damping valve device related to the use of the emergency operating armature is that the emergency operating armature is subject to a certain degree of damping of axial movement. This damping is based on the displacement of the damping medium through at least one (not identifiable in DE 10 2016 221 896 A1) axial flow connection between two spaces on either side of the emergency operating armature.

[0010] The emergency operating armature is under axial preload of a tension spring that moves the armature toward the pre-stage valve body. However, the pre-stage valve body's adjustment movement is undamped. This may cause the pre-stage valve body to lift off the emergency operating armature and exhibit ambiguous operating behavior. Summary of the Invention

[0011] The purpose of this invention is to provide a solution for a device for regulating damping force in a defined and demand-specific manner.

[0012] The objective is achieved by the following method: the stop is formed by a stop spring, which is functionally located between the emergency operation armature and the fore-stage valve.

[0013] The stop spring allows for axial movement of the upstream valve body and enables the reaction force to counteract extreme displacement of the valve armature. Due to this possible axial movement, even with significant lifting movement of the main valve, the pressure in the control chamber does not increase gradually as in the aforementioned prior art.

[0014] On the other hand, the valve armature applies a restoring force by means of a stop spring, which causes the emergency operation armature to shift or preload in the direction of its normal operating position.

[0015] Another advantage is that the inertia of the emergency operating armature only conditionally affects the action of the stop spring. The force flow from the tension spring through the emergency operating armature to the stop spring remains constant.

[0016] In another advantageous design, the stop spring has a minimum preload during normal operation of the damping valve assembly. Minimal preload means that a preload is already present during normal operation, small enough that no significant closing force acts on the upstream valve body. Thus, the preload is determined such that the stop spring is held within the damping valve assembly.

[0017] Alternatively, the stop spring can be preloaded only after the adjustment stroke of the valve armature related to the reduction of magnetic flux. This ensures that the stop spring only functions under very restricted operating conditions of the damping valve device. This provides structural freedom to increase the spring rate of the stop spring.

[0018] Regardless of the structural design of the stop spring, the advantage provided by this stop spring is that the fore-stage valve can have the same structural form regardless of the use of the emergency operation armature, and thus a standard design can be used for the structural form of the damping valve device with or without the emergency operation armature.

[0019] Optionally, the fore-stage valve body can abut against a rigid stop from the beginning of a defined operating stroke. The rigid stop is mechanically connected in parallel with a stop spring, and the stop spring reaches the length of the block. This protects the stop spring from overload.

[0020] When the stop spring is tensioned between the upstream valve body and the emergency operation armature, the stop spring should tend to have a small spring stiffness. Therefore, the stop element forms an anti-kink protection for the stop spring.

[0021] Preferably, the anti-kink protection is implemented on the emergency operation armature. In principle, the anti-kink protection can also be implemented on the fore-stage valve body, but in this case, great care must be taken not to adversely alter the hydraulic surface ratio. If it is assumed that the aforementioned technical problems occur during emergency operation, it is also meaningful to adjust the components related to emergency operation so that the valve components of the fore-stage valve can also be used in implementations without an emergency operation device.

[0022] Regarding the reliable guidance of the stop spring, the stop spring is at least indirectly connected to the emergency operating armature. Furthermore, it is thus possible to use a stop spring that does not apply preload to the upstream valve body during normal operation of the damping valve assembly. This connection can, for example, be formed as a simple radial clamping connection between the stop spring and the emergency operating armature.

[0023] In another advantageous design, the emergency operating armature has a rigid stop. When the lift stroke limiting section is activated due to the extreme hydraulic loading of the main stage valve and therefore also due to the forestage valve, the emergency operating armature is fixed relative to the damping valve body. Therefore, the tension spring of the emergency operating armature has no additional tension stroke. Consequently, there is no series connection between the stop spring and the tension spring. Overall, the effective spring rate is thus increased. Furthermore, the stop spring is mechanically connected in parallel with the spring assembly for the return movement of the valve armature, and therefore provides an increased reaction force to the forestage valve body overall.

[0024] A solution that is independent of the stop spring but can be combined involves the main valve body of the main valve working together with an end stop mechanism, which is activated when the main valve reaches its maximum open position.

[0025] This results in a limitation on the following function of the primary valve body to the upstream valve body. Therefore, at least the valve armature indirectly connected to the primary valve body can no longer be displaced to a degree of insufficient magnetic flux or excessive magnetic flux transition resistance.

[0026] It is proposed here that the end stop mechanism includes a stop surface on the emergency operation armature. A related advantage is that the surface on the main stage valve necessary for hydraulic pressure loading is not used as an end stop mechanism. Otherwise, it would be possible to achieve this function, for example, by using a hydraulically closed surface as a stop, but this would no longer be available as a closed surface in the stop position of the main stage valve body, and therefore the main stage valve would no longer be able to move to the closed position. Attached Figure Description

[0027] The present invention will be described in detail with the aid of the following accompanying drawings.

[0028] In the attached diagram:

[0029] Figure 1 A portion of the vibration damper within the damping valve assembly is shown.

[0030] Figure 2 It shows according to Figure 1 A portion of the damping valve device. Detailed Implementation

[0031] Figure 1 A damping valve device 1, as a component of the vibration damper 3, is shown. In this embodiment, the damping valve device 1 is arranged in a valve housing 5, which is fastened to an axially movable piston rod 7. The valve housing 5 carries a piston ring 9, such that the valve housing divides the cylinder 11 into a piston rod side filled with damping medium and a working chamber 13; 15 away from the piston rod. In principle, the invention is not limited to this spatial arrangement of the damping valve device 1.

[0032] The damping valve assembly 1 includes an electromagnetic actuator 17 having a valve armature 19 and an electromagnetic coil 21. The electromagnetic coil 21 is connected to a power supply line 23 within the piston rod 7. The actuator 17 is used to operate the pre-stage valve body 25 in the pre-stage valve 27, which in turn controls the main stage valve 29 of the damping valve assembly 1. The purpose of this valve structure is to allow control of a large closing force in the main stage valve 29 using a relatively small adjusting force from the actuator 17.

[0033] These two valves 27 and 29 are implemented as directional sequence valves. The main stage valve body 31 and the main stage valve seat 33 constitute the main stage valve 29. In this embodiment, an auxiliary valve 35 in the form of a passive damping valve is arranged in series with the main stage valve 29. The passive auxiliary damping valve provides the possibility of changing the basic damping force characteristic curve of the damping valve device 1. The two chambers 13 and 15 are hydraulically connected to each other via the main stage valve 29. Flow from the chamber furthest from the piston rod into the main stage valve is achieved through the auxiliary valve 35.

[0034] The main stage valve body 31 has an annular shoulder, the annular surface of which is a hydraulically loaded closed surface 37. A control channel 39 is implemented in the valve housing 5, which connects the piston rod-side working chamber 13 to an annular space 41, which is formed by the annular shoulder of the main stage valve body and the stepped opening 43 of the valve housing 5. A connecting channel 44 in the valve housing 5 is used to allow the main damping medium flow to flow between the piston rod-side working chamber 13 and the main stage valve. Therefore, when the piston rod moves out, the damping valve device 1 operates by means of the control channel 39 for controlling the flow of the damping medium to the upstream valve, and by means of the connecting channel 44 for the flow of the main damping medium.

[0035] The annular space 41 is connected to the pre-stage valve 27 via a radial channel 45 and an axial control channel 47 within the main stage valve body 31. The pre-stage valve seat surface 49, which forms the pre-stage valve 27 with the pre-stage valve body 25, is implemented on the annular tab 51 of the main stage valve body 31.

[0036] The fore-stage valve body 25 is connected to the valve armature 19 via a sliding connection. When the solenoid coil 21 is deactivated, the spring assemblies 53 on both sides hold the valve armature 19 in a defined initial position relative to the pole plate 55, which, together with the armature guide 57, return fluid 59, and emergency operation armature 61, forms the magnetic flux loop of the solenoid coil 21. Due to at least one axial channel 63, the valve armature 19 is always pressure balanced. Therefore, the fore-stage valve body 25 and the valve armature 19 always move synchronously during normal operation.

[0037] Based on the energization of the electromagnetic coil, the pressure drop between the control chamber 65 and the working chamber 13; 15 on the back side of the main valve body 31 is controlled during the inflow, thereby regulating the hydraulic closing force acting on the main valve body 31.

[0038] In the event of a power outage to actuator 17, damping valve device 1 has an emergency operation device 67 with an emergency operation armature 61 and a tension spring 69. As can be seen from the accompanying drawings, the emergency operation armature 61 has an annular shape with a stepped inner contour that overlaps axially with the pole plate 55. Upon application of current, the emergency operation armature 61 is lifted against the pole plate 55 against the force of the tension spring 69 and rests against the pole plate with an annular stop surface 71. The tension spring preloads the emergency operation armature 61 toward the main stage valve 29 and supports it on a component that is fixed in position to the valve housing 5.

[0039] In the direction toward the main stage valve body 31, the emergency operation armature 61 for the pre-stage valve 27 has a lift stroke limiter formed by a sleeve-shaped section 73 and is activated when limiting the lifting movement of the pre-stage valve body 25.

[0040] If only the actuator 17 or the solenoid coil 21 is slightly energized to achieve the gentle damping force characteristics of the damping valve device 1, then there is only a small axial overlap between the valve armature 19 and the pole plate 55 on their facing outer surfaces and a large axial gap on their facing end faces. Therefore, at this position, the resistance to the magnetic flux in the magnetic flux loop for the solenoid coil 21 also increases. Under strong hydraulic inflow to the main stage valve 29, the main stage valve body 31 displaces towards the preceding stage valve body 25 or the pole plate 55. The valve armature 19 also performs this displacement. Thus, the axial overlap between these two components is further reduced. Therefore, it is possible that, due to the minimization of the magnetic flux of the anti-tension spring 69 on the emergency operation armature 61, the holding force is no longer sufficient to hold the emergency operation armature 61 in its stop position on the pole plate 55, even with a complete power supply.

[0041] To eliminate this malfunction of the damping valve device 1, a stop 75 restricts the axial adjustment stroke of the fore-stage valve body 25, wherein the stop is formed by a stop spring 75, which is functionally implemented between the emergency operation armature 61 and the fore-stage valve 27.

[0042] In order to ensure that the stop spring 75 does not function throughout the entire adjustment range of the valve armature 19, the stop spring 75 has a minimum preload during normal operation of the damping valve device 1.

[0043] However, the dimensions of the stop spring 75 can also be designed such that the stop spring does not function when the damping force is adjusted and the volume flow is limited by the main valve 29, that is, it is not supported on the front valve body 25, i.e., the distance between the contact surface 77 on the back side of the front valve body 25 and the support surface 79 of the stop spring 75 on the emergency operation armature 61 is shorter than that in normal operation.

[0044] Such a short stop spring 75 allows for relative movement between the pre-stage valve body 25 and the emergency operation armature 61. However, due to the small mass of the stop spring 75, its effect on the damping valve assembly cannot be determined. During normal operation, with a correspondingly large hydraulic excitation and gentle damping force adjustment of the damping valve assembly, the spring force of the stop spring 75 acts in parallel with the magnetic force of the solenoid coil 21 and the spring force of the spring assembly 53.

[0045] In actual emergency operation, i.e., when the electromagnetic coil lacks power, the stop spring 75 continues to function in parallel with the spring assembly 53, but in series with the tension spring 69. The stop spring 75, with a shorter distance between the support surface 79 and the contact surface 77, achieves a higher spring rate. Due to the relatively high spring stiffness, the series connection of the stop spring 75 and the tension spring 69 has no negative impact. Importantly, the emergency operating armature is clamped between these two springs. As the frequency of the emergency operating armature 61 increases, it is also subjected to stronger damping due to the flow of damping medium through at least one compensation channel 78. Thus, the emergency operating armature 61 can occupy a quasi-static position, in which the stop spring 75 can support itself more effectively. Therefore, the series connection of the tension spring 69 and the stop spring 75 is functionally disabled, and the high spring stiffness of the stop spring 75 is achieved.

[0046] However, it can be proposed that the stop spring 75 be connected to the emergency operation armature 61 at least indirectly by radially pressing the stop spring 75 into the sleeve-shaped section 73.

[0047] In addition to the flexible stop 75, the fore-stage valve body 25 can also rest against the rigid stop 81 from the beginning of the defined operating stroke. The rigid stop is formed by the end face of the sleeve-shaped section 73.

[0048] In addition, the rigid stop 81 or sleeve-shaped section 73 of the emergency operation armature 61 constitutes an anti-kink protection for the stop spring 75.

[0049] In addition to the resilient stop 75, the damping valve assembly 1 also has a second device to prevent the valve armature 19 from moving out of the pole plate 55. This measure can be implemented independently of the resilient stop 75, but can also be implemented in combination. The concept is to limit the axial travel of the main stage valve body 31 and therefore also limit the displacement movement of the front stage valve body 25 and the displacement travel of the valve armature. For this purpose, the main stage valve body 31 of the main stage valve 29 works in conjunction with the end stop mechanism 83, which is activated when the main stage valve 29 reaches its maximum open position. Specifically from Figure 2As can be seen, the guide sleeve 85 of the main stage valve body 31 is implemented so long that the end of the guide sleeve 85 protrudes beyond the cover surface 87 of the intermediate housing component 89 in the direction toward the emergency operation armature 61. Therefore, the current protrusion does not improve the guide length on the main stage valve body 31 under any circumstances, but forms the aforementioned end stop mechanism 83. Here, the stop surface 91 of the end stop mechanism 83 is formed by the emergency operation armature 61. When extreme inflow occurs in the main stage valve 29, the forestage valve body and the main stage valve body 25; 31 move toward the pole plate 55. When the main stage valve body 31 is held in its maximum lifted position by the end stop mechanism 83, the lift of the forestage valve 27 can be increased independently of the energization of the actuator 17. The hydraulic displacement force of the main stage valve body 31 is no longer transmitted to the forestage valve body 25, so the spring assembly 53 and the magnetic force enable the valve armature 19 to fully overlap with the pole plate 55.

[0050] List of reference numerals

[0051] 1 Damping valve device

[0052] 3 Vibration dampers

[0053] 5 valve housing

[0054] 7 Piston Rod

[0055] 9 Piston rings

[0056] 11 Cylinder Block

[0057] 13. Piston rod side working chamber

[0058] 15. Workshops away from the piston rod

[0059] 17 Actuators

[0060] 19 Valve Armature

[0061] 21 Electromagnetic coil

[0062] 23 Power supply lines

[0063] 25. Forestage valve body

[0064] 27. Forestage valve

[0065] 29 Main stage valve

[0066] 31 Main stage valve body

[0067] 33 Main stage valve seat face

[0068] 35 Additional valve

[0069] 37 Closed surface

[0070] 39 Control Channels

[0071] 41. Circular Space

[0072] 43 Stepped opening

[0073] 44 Connection Channel

[0074] 45 Radial Channel

[0075] 47 Control Channel

[0076] 49. Front valve seat surface

[0077] 51 Annular splice

[0078] 53 Spring Assembly

[0079] 55 Extreme Disk

[0080] 57 Armature guide

[0081] 59 Return fluid

[0082] 61 Emergency Operation Armature

[0083] 63 Axial Channel

[0084] 65 Control Room

[0085] 67 Emergency Operation Device

[0086] 69 tension springs

[0087] 71 Stop surface

[0088] 73 Sleeve-shaped section

[0089] 75 Stop component

[0090] 77 Stop surface

[0091] 78 Compensation Channel

[0092] 79 Support surface

[0093] 81 Rigid stop

[0094] 83 End stop mechanism

[0095] 85 Guide Sleeve

[0096] 87 Cover

[0097] 89. Intermediate components of the housing

[0098] 91 Stop surface

Claims

1. A damping valve device (1) comprising an electromagnetic actuator (17) having a valve armature (19) for actuating a pre-stage valve body (25) in a pre-stage valve (27), wherein the pre-stage valve (27) actuates a master stage valve (29) of the damping valve device (1) and the pre-stage valve (27) and the master stage valve (29) are implemented as a sequence valve, wherein the damping valve device (1) has an emergency operating device (67) having an emergency operating armature (61) and a tension spring (69) preloading the emergency operating armature (61) toward the master stage valve (29), wherein a first stop restricts the axial adjustment stroke of the pre-stage valve body (25), characterized in that, The first stop is formed by a stop spring (75) which is functionally implemented between the emergency operation armature (61) and the fore-stage valve (27). The stop spring (75) has a minimum preload during normal operation of the damping valve device (1). The minimum preload means that a preload is already present during normal operation, which is small enough that no significant closing force is exerted on the fore-stage valve body. The stop spring is only preloaded after the adjustment stroke, which refers to the stroke of the valve armature related to the reduction of magnetic flux.

2. The damping valve device according to claim 1, characterized in that, The pre-valve body (25) rests against the rigid stop (81) from the beginning of the defined operating stroke.

3. The damping valve device according to claim 2, characterized in that, The rigid stop (81) forms an anti-kink protection for the stop spring (75).

4. The damping valve device according to claim 3, characterized in that, The anti-kink protection is implemented on the emergency operation armature (61).

5. The damping valve device according to any one of claims 1 to 4, characterized in that, The stop spring (75) is at least indirectly connected to the emergency operation armature (61).

6. The damping valve device according to claim 2, characterized in that, The emergency operation armature (61) has the rigid stop (81).

7. The damping valve device according to claim 1, characterized in that, The main valve body (31) of the main valve (29) works together with the end stop mechanism (83), which is activated when the main valve (29) reaches its maximum opening position.

8. The damping valve device according to claim 7, characterized in that, The end stop mechanism (83) includes a stop surface (91) on the emergency operation armature (61).

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