DE102005044233A1 - Hydraulically damping radial bearing e.g. hydraulic socket, has cavities connected with each other by damping channel that is parallely connected with bypass channel, which is closed by control valve that is controlled from outside - Google Patents

Abstract

The bearing has an elastomer part (10), which connects a fastening body (6) and a hollow cylindrical outer body (4). Two cavities are provided within the outer body, and are filled with hydraulic liquid. The cavities stay in connection with each other by a damping channel. The cavities form volume-adjustable hydraulic chambers (12a, 12b). The channel is parallely connected with a bypass channel (16), which is closed by a control valve (20) that is controlled from outside. The valve has an electro mechanical or pneumato-mechanically driven closure mechanism (22) with a stable end position.

Description

The The invention relates to a hydraulically-damped radial bearing (hydraulic Two-chamber socket), - according to the preamble of the claim.

hydraulic Radial bearings have long been known in various embodiments. They have a cylindrical inner part and a coaxially arranged, as a housing serving hollow cylindrical outer part on. Inner part and outer part are connected by a preferably two-legged elastomer part with each other connected. The above and below the elastomeric part existing cavities Make two with hydraulic fluid filled, alternately variable volume Chambers over a damper channel (Throttle channel) communicate with each other.

The Characteristic of the means of the damper channel realizable damping is in the usual radial bearings not changeable.

That in the FR 2.655.112 described hydraulic radial bearing has except a throttle channel ( 4 ), which connects two chambers (A) and (B), one in an inner part ( 8th ) integrated second channel ( 6 ) on. This second channel ( 6 ), which likewise connects the two chambers (A) and (B) via a partial chamber (A '), closes with the aid of a lip-shaped valve (FIG. 5 ) automatically if there are certain pressure situations within the hydro bearing.

From Outside can the damping characteristic neither controlled nor regulated.

Task of invention

The Object of the present invention is, starting from the to provide the said prior art, a radial bearing (a "hydraulic jack"), at the purpose of adaptation to different driving conditions influencing the Damping characteristic "from the outside" is possible. This is to be achieved in particular by an external controllability done a bypass valve.

Solution and advantages

According to claim 1, the bypass channel can be closed with the aid of an externally controllable valve. On this way can the damping and the dynamic stiffness can be changed in a wide range.

The Suspension sleeve according to the invention differs In that respect, from the prior art, as that the circuit pressure-independent and thus in certain driving conditions (e.g., speed> threshold speed) possible is.

Of the stiffness increase occurring with non-switchable suspension bushings and associated comfort loss is due to the opening of a Bypasses avoided.

The Bypass valve preferably has an electromechanical or pneumo-mechanical converter as a drive of a valve-closure mechanism. Such a thing a trained valve may e.g. from a central switching unit or driven by decentralized sensors via electrical lines become.

Around To avoid the electrical locking mechanism of the bypass valve constantly must be kept under power, it has at least one stable End position. In this way, energization is only required if a change the respective damping characteristic he wishes is or becomes necessary.

Except stable End positions are also stable intermediate settings (semi-open, three quarters open etc.) conceivable.

drawings

in the The following will be an embodiment of the Radial bearing according to the invention with the attached Drawings explained. It shows:

1 a radial bearing according to the invention ("hydraulic bushing") in cross section;

2 the same radial bearing in longitudinal section; and

3 the radial bearing in perspective view, partially cut open.

4 and 5 show diagrams relating to the operation of the radial bearing according to the invention, namely.

4 its damping; and

5 its dynamic rigidity, depending on the frequency.

description

This in 1 shown in longitudinal section Exemplary embodiment of the hydraulically damped radial bearing according to the invention ("hydraulic bushing") 2 has a sleeve-shaped outer body 4 and a coaxially arranged inner fastening body 6 (for example, to receive a journal). In the outer body 4 is a formed as a plastic half shell inner shell 8th pressed. The inner fastening body 6 is with the help of a two-legged elastomer part 10 with interposition of the inner jacket 8th elastically resilient on the sleeve-shaped outer body 4 supported.

That of the outer body 4 enclosed volumes 12 is due to the two-legged elastomer part 10 in an upper one 12a and in a lower chamber 12b divided. The two chambers 12a . 12b are filled with hydraulic fluid and via a molded into the inner shell annular channel 14 alternately variable in volume. Length and cross-sectional area of the ring channel 14 , which is also referred to as damper channel or throttle channel because of its damping effect, depend on the preferred frequency range to be damped. The damper channel 14 is tuned to low frequencies and is used in particular for the damping of steering wheel vibrations on a motor vehicle. For this purpose, the annular channel 14 be formed spirally with several rounds.

The hydraulically-damped Radial bearing according to the state The technology has comparable functional elements.

In addition to the two hydraulic chambers 12a . 12b connecting damper channel 14 has the radial bearing according to the invention 2 a controllable bypass channel 16 on. The bypass channel 16 is also in the formed as a plastic half shell inner shell 8th formed. Also the bypass channel 16 , the damper channel 14 is connected in parallel, connects the two hydraulic chambers 12a . 12b together.

The length of the bypass channel 16 is less than the length of the damper channel 14 , its cross-sectional area is larger, so that the bypass channel 16 Overall, a higher vote than the damper channel 14 , Another difference between bypass 16 and damper channel 14 is that the mouth (opening) 18 of the bypass channel 16 into the upper hydro chamber 12a with the help of the valve lifter 22 an electrically actuated valve 20 is closable.

With open bypass channel 16 can the fluid 12 through the opening 18 from the upper chamber 12a in the bypass channel 16 flow and there is a connection between the chambers 12a and 12b , By the pestle 22 the switching valve 20 can the opening 18 in the plastic half shell 8th be closed so that the fluid 12 only through the damper channel 14 between the chambers 12a and 12b can flow. With closed bypass channel 16 results in a low attenuation. This is associated with a stiffness increase in the frequency range with max. Damping. Constant travel at higher speeds requires low stiffness over a wider frequency range; on damping can be dispensed with. This will be the bypass 16 with the switching valve 20 open. The max. Damping and thus the increase in stiffness shifts to a higher frequency. As soon as the speed drops below a certain, predetermined limit (eg 110 km / h) or the brake pedal is pressed, the valve closes again.

To further illustrate the radial bearing according to the invention 2 like that 2 (Longitudinal section) and 3 (perspective view, partly cut open) contribute. Since the same components are denoted by the same reference numerals, a repetition of the relevant description is unnecessary.

In the 4 and 5 Diagrams show the damping ( 4 ) and the dynamic rigidity ( 5 ) of the bearing according to the invention 2 in each case depending on the excitation frequency ν. When the bypass is closed 16 only the effect of the damping channel comes 14 to carry. The maximum of the attenuation is in the lower frequency range, while with open bypass 16 the maximum is shifted to a higher frequency range. How out 5 can be seen by opening the bypass 16 The dynamic stiffness in the lower frequency range can be drastically reduced.

2

Radial bearings, Bearing, hydro bushing

4

Outer body, outer part

6

Mounting body, inner part

8th

Inner sheath, Plastic half shell

10

elastomer part

12

(from Enclosed space) volume, hydraulic fluid, fluid

12a, 12b

upper, lower (hydraulic) chamber, hydro chamber (s)

14

Annular channel, Muffler channel, throttle channel

16

Bypass, bypass channel

18

Opening, muzzle of the bypass channel

20

(Switch) valve, Bypass valve

22

Valve tappet, valve closure mechanism

Claims (3)

Hydraulic Radial Bearing ( 2 ) with an inner part ( 6 ) and with a coaxial thereto, hollow cylindrical outer part ( 4 ), both by an elastomeric part ( 10 ) are elastically resiliently connected to each other, wherein within the outer part ( 4 ) above and below the elastomeric part ( 10 ) existing cavities two filled with hydraulic fluid, via a damper channel ( 14 ), mutually volume variable chambers ( 12a . 12b ), and wherein the damper channel ( 14 ) a bypass channel ( 16 ) is connected in parallel, characterized in that the bypass channel ( 16 ) by means of an externally controllable valve ( 20 ) is closable. Radial bearing according to claim 1, characterized in that the valve ( 20 ) an electromechanically or pneumatically-mechanically driven locking mechanism ( 22 ) having. Radial bearing according to claim 1 or 2, characterized in that the locking mechanism ( 22 ) of the valve ( 20 ) has at least one stable end position.