DE4020045C1 - Hydraulic shock absorber for vehicle - has coil compression springs mounted between core housing and armature - Google Patents

Abstract

Hydraulic shock absorber comprises a fluid fulled damping cylinder divided into two spaces by the piston on its rod complete with valve-choked passages between the spaces. A tension and compression stage bypass is controlled in flow section by a three-stage magnetic valve using a magnet having two axially associated ring coils, one fixed to the core housing enclosing the valve. The second ring coil (15) should move relative the first coil (14) and an armature plate (18) should move vis-a-vis the second coil (15). Coil compression springs (19-21) are pref. mounted between the core housings (16, 17) and the armature (18). USE/ADVANTAGE - Motor vehicles. Bypass easily adjusted in variable absorber design in quick time, thus suited to high dynamic systems, ensuring riding comfort.

Description

The invention relates to a hydraulic vibration damper for Motor vehicles according to the preamble of patent claim 1.

To the driving behavior of a motor vehicle given the road Vibration dampers are a rule to be able to adjust conditions executed in cash. The damping valves in the damper piston additional adjustable bypass valves assigned. The regulation can be done via manually operated switches or also through an electronic program that according to different Input data controls vibration damping.

To adjust the bypass cross section, it is after DE 38 14 480 A1 known to use magnets, the throttle valves adjust in the form of sleeves. DE 38 14 480 A1 shows a Ma solenoid valve with a magnet that operates in three stages two concentrically arranged ring coils is. The magnet is located in the actual damping bulb. As a result, the damping piston must be made very high. According to DE 38 32 625 A1, it is also known a three-stage adjustment of the bypass cross-section by two axially to make successive magnets. Everyone is there Magnet connected to a slide valve, the associated one Bypass cross sections open or close. This design is required  disadvantageously also a large installation space. Beyond that, only a small bypass cross-section is available, as this type of construction relatively long central flow channel needed is limited by the internal dimensions of the magnets.

The invention has for its object a controllable Vibration damper according to the preamble of claim 1 to develop that he has a small space and from few components is assembled.

This task is characterized by the characteristics of the contractor spell 1 solved. Advantageous training results from the Features according to claims 2 to 5.

The advantages achieved with the invention are in particular in the fact that with a few simple components a sure function bypass adjustment for an adjustable hydraulic Vibration damper is achieved. The adjustment is extraordinary Lich fast, so that they can also be used for highly dynamic systems is cash. A conventional damping piston can be used that does not require special training.

An embodiment of the invention is shown in the drawing represents and is described in more detail below.

Show it:

Fig. 1 shows a section of a vibration damper in the region of the damping piston and

Fig. 2 shows a damping characteristic curve.

The shock absorber 1 has an outer cylinder 2 , the inner space of which is divided by a piston 3 into a lower working space 4 and an upper working space 5 . The piston 3 is formed in a known manner with damping valves (not shown) and is connected via a threaded section 6 and a nut 7 to the valve housing 8 of the bypass valve 9 . An adapter housing 10 connects the piston rod 12 to the valve housing 8 via a threaded shoulder 11 . The magnet 13 for moving the control slide consists of 2 ring coils 14 , 15 which are each arranged in a pot-shaped core housing 16 , 17 and a plat-shaped armature 18th The central axis of core housings 16 , 17 and armature 18 continue the central axis of the piston rod 12 , which is then followed by the piston 3 on the same central axis. Between the two core housings, two helical springs 19 , 20 are arranged centrally, which are electrically insulated from one another and from the core housing. These compression springs serve, on the one hand, to separate the core housing from one another in the de-energized state and, on the other hand, to ensure the electrical conductor for the current supply to the lower ring coil 15 . Between the lower core housing 17 and the armature 18 , a coil spring 21 is just arranged if centrally. This only ever serves to separate the armature from the lower ring coil 15 in the de-energized state. Core housing 16 , 17 and at ker 18 have a different outer diameter and who performed the in stepped holes in the valve housing. They lie in the de-energized state of the ring coils 14 , 15 on the shoulders of these stepped bores. The anchor 18 is also pot-shaped. Different control openings 23 , 24 are arranged on its peripheral wall, which cooperate with counter-openings 25 , 26 in the valve housing 8 . In the exemplary embodiment, control openings and counter-openings are slot-shaped. Flow openings 27 in the armature, 28 and 29 in the core housings 16 , 17 serve to ensure that damping medium located in the intermediate space between the core housing or between the lower core housing and the armature can flow out quickly, so that it does not act as a damping cushion and slow the control time. The two ring coils 14 , 15 are connected via a connection feed 30 , which is located within the hollow piston rod 12 , to connections to a central computer in the vehicle. The water central computer ensures that the bypass valve 9 is controlled accordingly to the desired control philosophy. At the same time, he ensures that the lower ring coil 15 is always actuated first and then the upper ring coil 14 . If the upper toroidal coil 14 is actuated alone, the bypass valve 9 remains closed, since then no movement of the armature 18 takes place. The two ring coils 14 , 15 are locked electronically and are controlled by the central computer in the vehicle.

With the object according to the invention, three different characteristic curves can thus be controlled in a vibration damper, but only two toroidal coils 14 , 15 with a core housing 16 , 17 are required. The bypass valve 9 can be used safely for both the rebound and compression stages of the vibration damper. For this reason, the driving comfort is adapted to the desired behavior in an inexpensive manner.

The interconnection of the ring coils 14 , 15 with their core housings 16 , 17 with the armature 18 basically represents a series connection of bypass openings. In the exemplary embodiment shown, the bypass valve is completely closed, as a result of which the vibration damper has the hardest identifier 31 when both ring coils 14 , 15 are off. In this case, the armature 18 is in the lowermost position as shown in FIG. 1. If current is applied to the lower toroidal coil 15 , an average identifier 32 results. Here, the two core housings 16 , 17 are separated and the ker 18 lies on the lower surface of the core housing 17 . A Wei che identifier 33 results when both ring coils 14 , 15 are supplied with current. Then both core housing 16 , 17 and the armature abut each other, whereby all control openings and counter openings are in the open state. Other functions can be selected.

Reference symbol list

1 shock absorber
2 cylinders
3 pistons
4 lower work area
5 upper work area
6 threaded section
7 mother
8 valve housing
9 bypass valve
10 adapter housing
11 thread approach
12 piston rod
13 magnet
14 ring coil
15 ring coil
16 core housing
17 core housing
18 anchors
19 coil spring
20 coil spring
21 coil spring
22 peripheral wall
23 control opening
24 control opening
25 counter opening
26 counter opening
27 flow opening
28 flow opening
29 flow opening
30 feeder
31 hard identifier
32 middle identifier
33 soft identifier

Claims (5)

1.Hydraulic vibration damper for motor vehicles with a cylinder containing a damping fluid, a plunging therein, sealed, axially displaceably arranged piston rod, at the lower end of which a damping piston is attached, which divides the cylinder space into two working spaces and which is provided with variable passages , which are controlled by throttle valve bodies and additionally have a bypass for the compression and rebound, whose bypass cross section through a three-stage solenoid valve with a magnet with two, each in a pot-shaped core housing, axially arranged ring coils, one of which is firmly connected to a housing is adjusted, characterized in that the second ring coil ( 15 ) relative to the first ring coil ( 14 ) and a plate-shaped armature ( 18 ) relative to the second ring coil ( 15 ) is axially movable Lich. 2. Hydraulic vibration damper according to claim 1, characterized in that between the core housing ( 16 , 17 ) and the armature ( 18 ) each have one or more coil springs ( 19 , 20 , 21 ) formed as compression springs. 3. Hydraulic vibration damper according to one of claims 1 or 2, characterized in that the armature ( 18 ) is cup-shaped and on its peripheral wall ( 22 ) Steueröffnun gene ( 23 , 24 ) having counter-openings ( 25 , 26 ) on the valve housing ( 8 ) interact. 4. Hydraulic vibration damper according to one of claims 1 to 3, characterized in that individual coil springs ( 19 , 20 ) are electrically insulated from other components as current-carrying contacts for an annular coil ( 15 ). 5. Hydraulic vibration damper according to one of claims 1 to 4, characterized in that in the de-energized state of the toroidal coils ( 14 , 15 ) the control openings ( 23 , 24 ) are closed against the counter-openings ( 25 , 26 ).