Adjustable damping valve device for a vibration damper

Abstract

Adjustable damping valve device for a vibration damper, comprising a valve housing with a sleeve section and a base, wherein the base and the sleeve section are designed as one piece, with a magnetic coil on a coil carrier which has a transverse web for guiding wire ends of the magnetic coil, wherein a magnetically conductive return body is operatively connected to the coil carrier at the end face and has a transverse groove for receiving the transverse web of the coil carrier, wherein the base of the valve housing has a partial thickening which forms the return body for the magnetic coil and delimits the transverse groove.

Description

[0001] The invention relates to an adjustable damping valve device for a vibration damper according to the preamble of patent claim 1.

[0002] DE 10 216 205 651 A1 describes an adjustable damping valve device for a vibration damper. The damping valve device comprises an outer valve housing in which a solenoid coil is arranged on a coil carrier. The coil carrier has a crosspiece in which a wire start and a wire end of the solenoid coil are guided toward a supply line.

[0003] A return element, separate from the valve housing, rests on the coil carrier and is in contact with the bottom of the valve housing at its front end. Towards the solenoid coil, the return element has a transverse groove for accommodating the crosspiece of the coil carrier.

[0004] To degas the valve chambers within the valve housing, the return body has a vent hole, which in turn means that the return body has numerous seals and a vent hole that is very demanding in terms of manufacturing technology and is dimensioned with a diameter of well under one millimeter.

[0005] To prevent the return path body from generating noise, a clearance-free fit is created between the return path body and the valve housing in the radial direction. Solving the noise problem at the return path body increases the manufacturing effort for the clearance-free fit.

[0006] Due, among other things, to the complex degassing of the valve chambers, DE 10 2021 201 890 B3 proposes a separate return body made of a sintered material, which, in addition to the degassing function, offers the advantage of simple production.

[0007] In contrast to DE 10 2016 205 651 A1, the coil carrier in DE 10 2021 201 890 B3 is designed with a crossbar that is limited to half the diameter starting from an outer edge. In DE 10 2016 205 651 A1, the crossbar extends over the entire frontal diameter of the coil carrier.

[0008] DE 10 2009 059 808 A1 describes a damping valve device on a piston rod, wherein a coil carrier, a magnetic coil and a return body form a self-contained assembly by means of an outer coating.

[0009] DE 10 2014 208 367 A1 discloses a damping valve device for external installation on a vibration damper. This design uses a pot-shaped return element that is firmly connected to a valve housing of the damping valve device, e.g., by means of a material-to-material bonding process or, for example, by force-fitting.

[0010] The object of the present invention is to further develop an adjustable damping valve device in such a way that a simple structural design and thus a simplified assembly of the damping valve device is achieved.

[0011] The problem is solved by the features of patent claim 1.

[0012] Functionally, a one-piece design is achieved between the previously separate return path body and the valve housing. This eliminates air gaps between the return path body and the base, improving the magnetic flux of the solenoid for the adjustment function and increasing the mechanical load capacity of the valve housing. Furthermore, the manufacturing step of installing the return path body is eliminated. The recess within the coil carrier simplifies the manufacture of the valve housing, as the transverse groove in the base can be shortened.

[0013] In a further advantageous embodiment, the transverse groove has a rectangular basic shape with a length-to-width ratio in the longitudinal direction of > 1 and a distance from the inner surface of the sleeve section at the end. The transverse groove thus does not extend across the entire base diameter, but is optimized for the length of the bridge on the coil carrier. Consequently, a larger contact area is available at the front for the magnetic flux transfer to a guide body within the magnetic coil.

[0014] According to an advantageous subclaim, the valve housing, including its return body and the sleeve section, is manufactured using a forming process in the area of the base. This creates a seamless base body with optimal mechanical and conductive properties. Unlike a separate return body, this solution eliminates rattling noises.

[0015] In addition, the inner surface of the sleeve section has a machined surface to ensure optimal installation conditions for the solenoid coil. The transverse groove in the base does not require any mechanical remachining. Due to the axial length of the sleeve section, machining the transverse groove would require a particularly long end mill, which, due to its inherent design, would have a limited service life.

[0016] As a further functional improvement, a guide sleeve for a valve armature within the solenoid coil features a transverse slot on the front side, into which the crossbar of the coil carrier engages in the direction of the solenoid coil. This allows a component that conducts the magnetic flux to rest directly against the return path on the bottom side.

[0017] Additionally, the guide sleeve for the valve armature can be provided to extend axially beyond the annular collar of the coil carrier, with the bottom of the valve housing having a stepped profile with a first contact surface for the coil carrier and a stepped second contact surface for the guide sleeve. The axial projection of the guide sleeve relative to the coil carrier simplifies a flow path for venting the damping valve device.

[0018] For a simple design of the venting, the guide sleeve has an external venting groove which is connected to a venting opening in the valve housing.

[0019] In a further design refinement, the guide sleeve features a connecting channel that connects the interior of the guide sleeve to the external venting groove. The previously extremely small vent hole can now be made significantly larger.

[0020] Another measure to simplify venting the damping valve assembly is to incorporate a section of the connecting channel into a guide for a valve armature within the guide sleeve. By using the guide as a connecting channel, a separate connecting channel can be eliminated.

[0021] The invention will be explained in more detail with reference to the following figures. It shows: Fig. 1 and 2 sections through the adjustable damping valve device Fig. 3 to 5 External views of the coil carrier with the magnetic coil Fig. 6 Perspective view of the valve housing Fig. 7 Perspective view of the guide sleeve after Fig. 1 and 2 Fig. 8 and 9 Top view of the coil carrier with crossbar Fig. 10 and 11 Excerpts from the Fig. 1 and 2 in the area of the crossbar Fig. 12 Detailed view of Fig. 10 and 11.

[0022] The Fig. 1 and Fig. 2 each show a section through an adjustable damping valve device 1 for a vibration damper 3. The adjustable damping valve device 1 comprises a valve housing 5, which in this exemplary embodiment is arranged on an axially movable piston rod 5 within a working cylinder 9 of the vibration damper 1. In principle, it is also possible for the damping valve device 1 to be used outside the working cylinder 9 and even spatially separated from the working cylinder 9, for example by means of a hose or pipe connection. The invention is not restricted to a specific design of the vibration damper 1.

[0023] The valve housing 5 has a piston section 11 that separates a working chamber 13; 15 on the piston rod side from a working chamber 13; 15 remote from the piston rod within the working cylinder 9. Furthermore, the valve housing 5 comprises a sleeve section 17 and a base 19, wherein the base 19 and the sleeve section 17 are formed as a single piece. An actuator 21 of the damping valve device 1 is formed by a solenoid coil 23 on a coil carrier 25 and controls, for example, a pilot valve (not shown). The structure of the pilot valve and a main stage valve connected thereto are known, for example, from DE 10 2021 201 890 B3, although the invention is not necessarily limited to the combination of a pilot valve with a main stage valve.

[0024] Within the valve housing 5, the actuator 21 comprises a stationary guide sleeve 27 for a valve armature 29, which performs an axial adjustment movement. Axially below the coil carrier 25 is an annular insulator or magnetic flux resistor 31, against which a pole disk 33 is supported. The coil carrier 25 and the guide sleeve 27 are axially fixed within the valve housing 5 via an annular intermediate wall 35.

[0025] The coil carrier 25 has a crosspiece 37 for guiding and connecting end turns 39; 41 and strands 43; 45 of a supply line 47 for the magnetic coil 23. In this embodiment, the crosspiece 37 extends over the entire inner diameter of the tubular coil carrier 25, as can be seen in particular from the synopsis of the Fig. 3 to 5. The magnetic flux 49 of the solenoid coil 23 is optimized for the greatest possible actuator force. For this purpose, a magnetically conductive return body 51 is operatively connected to the coil carrier 25 at the front and has a transverse groove 53 for receiving the transverse web 37 of the coil carrier. The base 19 of the valve housing 5 has a partial thickening, which forms the return body 51 for the solenoid coil 23 and delimits the transverse groove 53. The thickening or the return body 51 is in Fig. 2 shown with a dash-dotted contour.

[0026] The Fig. 6 shows the valve housing 5 without the piston section 11 as a single part in a perspective view looking at the bottom 19 of the valve housing 5, so that one half of the transverse groove 53 can be seen in the bottom 19. The transverse groove 53 essentially has a rectangular basic shape with a length-to-width ratio > 1 in the longitudinal direction, wherein the transverse groove 53 has a distance 57 at the end to an inner circumferential surface 55 of the sleeve section in the longitudinal direction.

[0027] The valve housing 5 is preferably manufactured by means of a forming process in the area of the base 19 with its return body 51 and the sleeve section 17. Despite the forming process, the base 19, with its return body function, can have a significantly greater wall thickness than the sleeve section 17, whose inner surface 55 has a machined surface. The machined surface guarantees a high radial fit, particularly for the solenoid coil 23.

[0028] The transverse groove 53 is not subject to machining. The dimensional and shape accuracy achievable with the forming process, e.g., drop forging, meets the requirements.

[0029] The Fig. 7 and Fig. 8 show the coil carrier 25 with the wound magnetic coil 23 with a view of the crosspiece 37 of the coil carrier 25, to which a supply line 47 with at least two wires is connected, which runs inside the hollow piston rod 7 ( Fig. 1 and Fig. 2). Both strands 43; 45 of the supply lines 47 extend radially outward into a clamp within a groove 59 of the crosspiece 37.

[0030] The coil carrier 25 has an annular collar 61 on its end face, at least in the direction of the bottom 19 of the valve housing 5, for axially limiting the solenoid coil 23. In this embodiment, the coil carrier 25 has an annular collar 61; 63 on both end faces. The annular collar 61, connected to the transverse web 37, has radial recesses 65; 66 extending from the outer diameter, which overlap with the transverse groove 53 in the bottom 19 of the valve housing 5. The radial recess 65 for the outer end turn 39 has a triangular shape and enables a tangential transition of the outer end turn 39 of the magnetic coil 25 into the groove 59 of the transverse web 37. From the radially deepest point of the recess 65, a ramp 67 on the collar 61 extends in the winding direction of the magnetic coil 25 at least as far as an inlet opening 69 for the outer end turn 39 into the groove 59 of the transverse web 37.The inlet opening 69 has a deflection area 71 that receives the wire of the outer end turn 39 and prevents the outer end turn 39 from migrating radially outward. At least one deflection profile 73 is present within the groove 59, so that the outer end turn 39 can be pre-tensioned and inserted into the groove 59 via the recess 65 and the deflection area 71. The recess 66 can be designed with a simpler geometry due to the direct intersection with the transverse groove 53.

[0031] The Fig. Figure 9 shows the guide sleeve 27 for the valve armature 29 as a single part. On the front side, the guide sleeve 27 has a transverse slot 75 within the solenoid coil 23, into which the transverse web 37 of the coil carrier 25 engages in the direction of the solenoid coil 23.

[0032] As seen in conjunction with the Fig. 10 and Fig. 11, the guide sleeve 27 for the valve armature 29 extends axially beyond the annular collar 61 of the coil carrier 25. The base 17 of the valve housing 5 has a stepped profile with a first contact surface 77 for the annular collar 61 of the coil carrier 25 and a stepped second contact surface 79 for an end face 81 of the guide sleeve 27. Consequently, both components are in contact with the base 19 or return body 51 of the valve housing 5. Fig. 3 to 5, elastic support elements can be seen on the lower circumferential collar 63, which ensure tolerance compensation so that there is no double fit of the guide sleeve 27 and the coil carrier 25 to the bottom 19 of the valve housing 5.

[0033] During assembly of the damping valve device 1, despite careful flushing of the damping valve device 1 with damping medium, a small amount of air can collect within the guide sleeve 27. In order to discharge this amount of air from the damping valve device 1, the guide sleeve 27 has an external venting groove 83, which is connected to a venting opening 85 in the valve housing 5. The venting groove 83 enables any circumferential assignment of the guide sleeve 27 to the venting opening 85. Furthermore, the guide sleeve 27 has a connecting channel 87, which connects an interior space 89 of the guide sleeve 27 to the external venting groove 83. A section of the connecting channel 87 is formed by a guide 91 for the valve armature 29 within the guide sleeve 27. Thus, a connection exists between the interior space 89 of the guide sleeve 27 and the piston rod-side working chamber 13. The overview of the Fig. 10 and 11 show an enlarged section of the damping valve device 1 in the area of the transverse web 37 of the coil carrier 25. The guide for the valve armature 29 is formed by an axial opening 93 within a base 95 of the guide sleeve 27 and has guide segments 97 separated by the axial channels 87. The axial opening 93 opens into the end-face transverse slot 75 of the guide sleeve 27.

[0034] As the Fig. 10 shows, there is a gap 99 between the transverse slot 75 of the guide sleeve 27 and the transverse web 37 of the coil carrier 25, so that there is also a second gap 101 between the return body 51 on the bottom 19 of the valve housing 5 and the transverse web 37, which extends as far as the venting groove 81 in the guide sleeve 27. Axially just below the return body 51 there is the interface between the venting groove 83 and the venting opening 85 in the valve housing 5. The effective cross section of the venting channel is formed by the venting groove 83, which is very easy to manufacture even with a small cross section due to its external arrangement on the guide sleeve 27.

[0035] During the manufacturing process of the adjustable damping valve device 1, the valve housing 5 is formed from a blank. At the end of the forming process, a one-piece valve housing 5 is obtained with a base 19, in which the transverse groove 53 for the transverse web 37 of the coil carrier 25 is already formed. The transverse groove 53 extends longitudinally across almost the entire base 19 of the valve housing 5. As the figures show, the wall thickness of the base is significantly greater than the wall thickness of the sleeve section 17, so that the base 19 has a low magnetic flux resistance.

[0036] The sleeve section 17 is then turned to its nominal diameter. The material loss due to machining increases the radial distance 57 between the ends of the transverse groove 53 in the base 19 and the sleeve section 17. The chip removal results in the first contact surface 77 for the annular collar 61 of the coil carrier 25.

[0037] The inner and outer end turns 39; 41 of the magnetic coil 25 are threaded into the recesses 65; 66 of the coil carrier 25 under pretension and connected to the contact points on the crosspiece 37 of the coil carrier 25 with the strands 43; 45 of the supply line 47.

[0038] In a further step, the coil carrier 25 is inserted into the valve housing 5 or the hollow piston rod 7 together with the supply line 47 and a ring seal 103. At the end of this step, the circumferential collar 61 rests against the first stop surface 77. In the enlarged view according to Fig. 12 shows the course of the outer end turn 39 along the V-shaped receptacle 65 in the collar 61 and the further path over the ramp 67. The outer end turn 39 therefore has a small axial clearance, so that the circumferential collar 61 rests against the first stop surface 77 over a large area. Fig. 3 and Fig.4 it can also be seen that the outer end turn 39 extends axially above the circumferential collar 61 only from the entry into the transverse web 37, but otherwise runs in the receptacle 65 and rises via the ramp 67 into the cross-sectional area of the transverse groove 53 of the base 19.

[0039] The guide sleeve 27 for the valve armature 29 is then inserted into the coil carrier 25 until the guide sleeve 27 rests against the base 19 or the return body 51 of the valve housing 5. The other valve components are then fed through the open end of the valve housing 5.

[0040] During the flushing process, air is discharged from the interior of the damping valve device 1 via the interior space 89 of the guide sleeve 27, the guide 91 for the valve armature 29 and the gap 99; 101 in the space between the transverse slot 75 and the guide sleeve 27, the transverse web 37 of the coil carrier 25 and the transverse groove 53 in the base 19 of the valve housing 5 as well as via the vent groove 83 at the vent opening 85. Reference symbol 1 adjustable damping valve device 3 vibration dampers 5 valve housing 7 Piston rod 9 working cylinders 11 Piston section on the valve housing 13 piston rod side working space 15 working area remote from the piston rod 17 Sleeve section 19 Bottom of the valve housing 21 Actuator 23 Solenoid coil 25 coil carriers 27 Guide sleeve 29 valve anchors 31 Insulator 33 Pole disc 35 Partition wall 37 Crossbar of the coil carrier 39 outer end turn of the magnetic coil 41 inner end turn of the magnetic coil 43 strands 45 strands 47 supply line 49 Magnetic flux 51 Return body 53 Cross groove 55 inner surface of the valve housing 57 Distance of the transverse groove to the inner surface of the valve body 59 Gutter of the crosspiece 61 annular collar 63 annular collar 65 radial recess (outer end turn) 66 radial recess (inner end turn) 67 Ramp 69 Entrance opening 71 Deflection area 73 Deflection profile 75 cross slot 77 first investment area 79 second contact surface 81 End face of the guide sleeve 83 venting groove 85 vent opening 87 connecting channel 89 Interior of the guide sleeve 91 Guide 93 Axial opening 95 Bottom of the guide sleeve 97 Guide gap 99 gap 101 second gap 103 Ring seal

Claims

[1] Adjustable damping valve device (1) for a vibration damper (3), comprising a valve housing (5) with a sleeve section (17) and a base (19), wherein the base (17) and the sleeve section (17) are designed as one piece, with a magnetic coil (23) on a coil carrier (25) which has a transverse web (37) for guiding end turns (39; 41) of the magnetic coil (23), wherein a magnetically conductive return body (51) is operatively connected to the coil carrier (25) at its end face and has a transverse groove (53) for receiving the transverse web (37) of the coil carrier (25), characterized byin that the base (19) of the valve housing (5) has a partial thickening which forms the return body (51) for the magnetic coil (23) and delimits the transverse groove (53), wherein the transverse groove (53) has a rectangular basic shape with a length-width ratio in the longitudinal direction > 1 and has a distance (57) at the end to an inner circumferential surface (55) of the sleeve section, wherein the coil carrier (25) has an annular collar (61) on the end face in the direction of the base (19) of the valve housing (5) for axially delimiting the magnetic coil (23), wherein the annular collar (61) has a radial recess (65; 66) which is in radial overlap with the transverse groove (53) in the base (19). [2] Adjustable damping valve device (1) according to claim 1, characterized by that the valve housing (5) in the region of the base (19) with its return body (51) and the sleeve section (17) is produced by means of a forming process. [3] Adjustable damping valve device (1) according to claim 1, characterized by that an inner circumferential surface (55) of the sleeve portion (17) has a machined surface. [4] Adjustable damping valve device (1) according to at least one of claims 1 to 3, characterized by that a guide sleeve (27) for a valve armature (29) within the magnetic coil (23) has a front-side transverse slot (75) into which the transverse web (37) of the coil carrier (25) engages in the direction of the magnetic coil (23). [5] Adjustable damping valve device (1) according to at least one of claims 1 to 4, characterized by that the guide sleeve (27) for the valve armature (29) extends axially beyond the annular collar (61) of the coil carrier (25), wherein the bottom (19) of the valve housing (5) has a stepped profile with a first contact surface (77) for the coil carrier and a stepped second contact surface (79) for the guide sleeve (27). [6] Adjustable damping valve device (1) according to at least one of claims 1 to 5, characterized by that the guide sleeve (27) has an external venting groove (83) which is connected to a venting opening (85) in the valve housing (5). [7] Adjustable damping valve device (1) according to claim 6, characterized by that the guide sleeve (27) has a connecting channel (87) which connects an interior space (89) of the guide sleeve (27) to the external venting groove (83). [8] Adjustable damping valve device (1) according to claim 7, characterized by that a section of the connecting channel (87) is formed by a guide (91) for the valve armature (29) within the guide sleeve (27).

Images