DE102017216662B4 - Damping arrangement for a vibration damper of a motor vehicle - Google Patents

Abstract

Damping arrangement (1) for a vibration damper (2) of a motor vehicle, comprising: - a damping piston (5) displaceably arranged within a damper cylinder (3) and fixed to a piston rod (4), which divides the damper cylinder interior into a pressure chamber (6) and a second Cylinder chamber (7) divided, - with a damping valve (8) with at least one first flow channel (10) designed in the damping piston (5) for a damping fluid, which is covered by at least one valve disk (9) - at least one constantly acting, second flow channel (11), which is functionally parallel to the first flow channel (10), wherein both flow channels (10, 11) are flowed through by a damping fluid, characterized in that the damping arrangement (1) is within the pressure chamber (6), adjacent to the Damping piston (5) arranged closure arrangement (12), wherein the closure arrangement (12) is designed such that it at least partially closes the second flow channel (11) when the damping fluid pressure in the pressure chamber (6) increases sharply.

Description

The invention relates to a damping arrangement for a vibration damper of a motor vehicle according to the preamble of patent claim 1.

A vibration damper is usually arranged between a wheel suspension and the body of a motor vehicle and has the task of dampening the shocks coming from the wheel suspension and at least mitigating the transmission of these shocks to the body of the motor vehicle.

A generic damping arrangement usually comprises a damping piston which is displaceably arranged within a damper cylinder and fixed to a piston rod, which divides the damper cylinder interior into a pressure chamber and a second cylinder chamber and comprises a damping valve which has a first flow channel for a damping fluid, which connects the pressure chamber with the connects the second cylinder chamber, the first flow channel being covered by a spring-loaded or resilient valve disk. As a rule, a suitable, practically incompressible damping fluid, such as oil or an oil mixture, is used as the damping fluid. The damping valve is set so that when a defined pressure of the damping fluid in the pressure chamber is exceeded, the valve disk lifts off the flow channel and at least partially opens it, whereby the damping fluid can flow through the flow channel. Since the valve disk is spring-loaded, it generates resistance which acts against the flow direction of the damping fluid, which creates a damping effect of the vibration damper.

In order to open the valve disk, a defined contact pressure of the spring-loaded and/or resilient valve disk at the outlet end of the first flow channel must first be overcome. It cannot therefore be ruled out that the shocks that are too small to overcome this pressure limit are transmitted to the body, which would make driving through cobblestones, for example, quite unpleasant.

In order to solve this problem, the damping arrangement is usually equipped with at least one so-called bypass. This is at least one further, additional constantly acting, i.e. permanently open, flow channel, which has a significantly smaller, defined cross section than the first flow channel. The second flow channel is usually arranged functionally parallel to the first flow channel and also connects the pressure chamber with the second cylinder chamber. A damping fluid also flows through the second flow channel and allows the damping fluid to bypass the valve disk of the damping valve in the event of smaller shocks. In this way, the damping arrangement reduces the impact energy without transferring it to the body.

Due to the usually very high working pressures and flow velocities, motor vehicle vibration dampers, especially in the commercial vehicle sector, occasionally have problems with hissing noises, which can be heard within the driver's cab and are perceived as unpleasant. These arise, among other things, from the fact that during operation of the vibration damper, especially during larger compression and rebound movements, the damping fluid flow flows out of the pressure chamber into the second cylinder chamber through the second flow channel under a very high pressure.

From the US 8,714,320 B2 a damping valve is known whose flow connection between two working spaces has two damping valves in a hydraulic series connection. One of the damping valves generates an adapted damping force regardless of the flow speed within said damping valve. The other damping valve assumes a throttle position above a defined load starting from a maximum passage position.

In the DE 27 21 933 A1 A damping valve has a valve disk arrangement that interacts with a valve seat surface on both sides. In a starting position of the valve disk arrangement, it is prestressed on a first valve seat surface and lifts off the first valve seat surface when there is an inflow. In the case of a borderline flow, the valve disk arrangement approaches the second valve seat surface, so that the damping force increases due to the resulting narrowing throttle cross section.

The object of this invention is therefore to provide an alternative damping arrangement for a vibration damper of a motor vehicle, which overcomes the problem explained above.

This object is achieved according to the characterizing part of patent claim 1 in that the damping arrangement comprises a closure arrangement arranged within the pressure chamber adjacent to the damping piston, the closure arrangement being designed in such a way that when the damping fluid pressure increases sharply in the pressure chamber this at least partially closes the second flow channel.

This ensures that at high working pressure and flow speed of the damping fluid, the bypass is closed and the escape of the damping fluid is interrupted, whereby the hissing noises are significantly minimized.

Further advantageous embodiment variants are specified in the dependent claims.

According to an advantageous embodiment variant, it can be provided that the closure arrangement is designed in a very simple and cost-effective manner by comprising a spacer component and at least one spring-loaded or resilient closure component arranged adjacent thereto. The spacer component and/or the closure component can advantageously be designed in a disk shape and, for example, can be stamped very cost-effectively from a flat semi-finished product.

According to an advantageous embodiment variant, the closure component can be made of a reversibly deformable material, of a metal or of a plastic or of rubber.

According to a further advantageous embodiment variant, it can be provided that the closure arrangement further comprises a pre-throttle component which has at least one opening or bore for the initial adjustment of the damping fluid flow in the second flow channel. The pre-throttle component can be designed as a disk and include several openings, which are arranged at a defined distance from the center of the pre-throttle component.

According to a further advantage, the initial setting of the damping fluid flow in the second flow channel can alternatively be realized by making at least one opening and/or recess and/or groove on the spacer component, which forms a channel for the damping fluid, the channel being in the second flow channel opens.

The invention will now be explained in more detail using the following figures.

• 1: eine Schnittdarstellung eines Abschnitts einer Dämpfungsanordnung gemäß Patentanspruch 1;
• 2 eine Schnittdarstellung einer Dämpfungsanordnung gemäß 1 mit einem ausgelenkten Verschlussbauteil;

Show it:

• 1 : a sectional view of a section of a damping arrangement according to claim 1;
• 2 a sectional view of a damping arrangement according to 1 with a deflected closure component;

The 1 shows a first exemplary embodiment variant of a vibration damper 2 with a damping arrangement 1 according to the invention. The damping arrangement 1 comprises a damping piston 5 which is displaceably arranged within a damper cylinder 3 and fastened to a piston rod 4. This divides the damper cylinder interior into two cylinder spaces. During a deflection movement or a rebound movement, the damping piston 5 attached to the piston rod 4 shifts axially within the damper cylinder 3. A cylinder space is reduced in size, as a result of which the damping fluid pressure increases in it and the opposite cylinder space increases, resulting in a falling damping fluid pressure in this space results. The reduced cylinder space with a high damping fluid pressure within the space is hereinafter called a pressure space 6, with the enlarged cylinder space being called a second cylinder space 7. For convenience, in the 1 and 2 the state is shown in which the pressure chamber 6 is arranged above the damping piston 5 and the second cylinder chamber 7 is arranged below the damping piston 5. The direction of movement of the damping piston 4 attached to the piston rod 4 within the damper cylinder 3 is represented by an arrow pointing vertically upwards and running axially with respect to the longitudinal axis L of the damping arrangement 1.

The damping piston 5 further comprises a damping valve 8 with at least a first flow channel 10 for a damping fluid, which is designed in the damping piston 5 and is covered by at least one valve disk 9. At a defined pressure difference in the cylinder chambers, the resilient valve disk 9 lifts slightly, whereby the damping fluid passes through the first flow channel from the pressure chamber 6 into the second cylinder chamber 7. This primary damping fluid stream 19 is in the 1 and 2 shown as a broken line, with the direction of flow shown as an arrow at the end of this line.

Furthermore, the damping arrangement 1 comprises at least one constantly acting, functionally parallel to the first flow channel 10, second flow channel 11, which acts as a bypass and the damping fluid parallel to the primary damping fluid flow 19 as a secondary damping fluid flow 20 past the damping valve 8, from which Pressure chamber leads into the second cylinder chamber. The two flow channels 10, 11 who a damping fluid flows through it during operation.

The ones in the 1 and 2 Damping arrangement 1 shown further comprises a closure arrangement 12 arranged within the pressure chamber 6. This is mounted adjacent to the damping piston 5 and comprises a disk-shaped closure component 14, two spacer components 13, which are also disk-shaped, and a pre-throttle component 15.

That in the 1 and 2 Closure component 14 shown is made of a reversibly deformable material. A reversibly deformable material can be any suitable material that can change its shape when the damping fluid pressure increases sharply and can restore the original shape when the damping fluid pressure falls. It can be a metal or a plastic with or without fiber reinforcement, as well as a rubber or a rubber mixture. The 2 shows that the closure arrangement 12 is designed such that it closes the second flow channel 11 when the damping fluid pressure in the pressure chamber 6 increases sharply.

How it is in the 1 and 2 is shown, the pre-throttle component 15 has at least one opening 16, which is shown here as a bore. By choosing the size of the opening 16 or the number of openings 16, the damping fluid flow can be initially preset.

In addition, show you 1 and 2 in that the closure arrangement 12 further comprises a support component 21 arranged between the pre-throttling component 15 and the damping piston, which comprises at least one channel 17 for the damping fluid, which opens into the second flow channel 11. It can also be provided, although not shown here, to form the channel 17 on at least one spacer component 13. The flow channel 11 is in the embodiment variants shown 1 and 2 designed as a recess extending axially along a section 18 of the piston rod 4. An embodiment as a groove or bore, which is attached to the piston rod 4 or to the damping piston 5, is also possible.

Reference symbols

1

Damping arrangement

2

Vibration damper

3

Damper cylinder

4

Piston rod

5

Damping piston

6

Pressure room

7

second cylinder chamber

8th

Damping valve

9

Valve disc

10

first flow channel

11

second flow channel

12

Closure arrangement

13

Spacer component

14

Closure component

15

Pre-throttle component

16

breakthrough

17

channel

18

Section of the piston rod

19

Primary damping fluid flow

20

Secondary damping fluid flow

21

Supporting component

22

Fastening component

L

Longitudinal axis

Claims (10)

Damping arrangement (1) for a vibration damper (2) of a motor vehicle, comprising: - a damping piston (5) displaceably arranged within a damper cylinder (3) and fixed to a piston rod (4), which divides the damper cylinder interior into a pressure chamber (6) and a second Cylinder chamber (7) divided, - with a damping valve (8) with at least one first flow channel (10) designed in the damping piston (5) for a damping fluid, which is covered by at least one valve disk (9) - at least one constantly acting, second flow channel (11), which is functionally parallel to the first flow channel (10), wherein both flow channels (10, 11) are flowed through by a damping fluid, characterized in that the damping arrangement (1) is within the pressure chamber (6), adjacent to the Damping piston (5) arranged closure arrangement (12), wherein the closure arrangement (12) is designed such that it at least partially closes the second flow channel (11) when the damping fluid pressure in the pressure chamber (6) increases sharply. Damping arrangement (1). Claim 1 , characterized in that the closure arrangement (12) has at least one spacer component (13) and at least one spring-loaded or resilient closure component (14) arranged adjacent thereto. Damping arrangement (1). Claim 1 or 2 , characterized in that the closure component (14) and/or the spacer component (13) is designed in the shape of a disk. Damping arrangement (1) according to at least one of the preceding claims, characterized in that the closure component (14) is made of a reversibly deformable material. Damping arrangement (1). Claim 4 , characterized in that the closure component (14) and/or the spacer component (13) is made of a metal. Damping arrangement (1). Claim 4 , characterized in that the closure component (14) and/or the spacer component (13) is made of a plastic. Damping arrangement (1) according to at least one of the preceding claims, characterized in that the closure arrangement (12) comprises a pre-throttle component (15) which has at least one opening (16) for initially setting the damping fluid flow in the second flow channel (11). Damping arrangement (1) according to at least one of the preceding claims, characterized in that the spacer component (13) comprises at least one channel (17) for the damping fluid, which opens into the second flow channel (11). Vibration damper (2) of a motor vehicle with a damping arrangement (1), characterized in that the damping arrangement (1) is designed according to at least one of the preceding claims. Vibration damper (2). Claim 9 , characterized in that the second flow channel (11) is at least partially designed as a recess or groove or bore extending axially along a section (18) of the piston rod (4).

Images