Support bearing

Abstract

The invention relates to a support bearing with a damping channel linking a working chamber and a compensation chamber. The damping channel is provided with a damping channel orifice that can be opened and closed with a plug. Until now, high pressing forces were required to keep the damping channel orifice closed with the plug at peak pressures. The present invention markedly reduces the pressing forces with which the plug must be pressed against the damping channel orifice at peak pressures. In the support bearing of the invention, the plug can be pressed against the damping channel orifice from the direction of the working chamber.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of German Patent Application 103 59 639.9, filed Dec. 18, 2003. The disclosure of the above application is incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a support bearing with a damping channel linking a working chamber and a compensation chamber. The damping channel is provided with a damping channel orifice that can be opened and closed with a plug.

BACKGROUND OF THE INVENTION

Many possible ways of closing an orifice of a damping channel are known from the prior art. For example, it is possible for the damping channel orifice to be closed with a steel spring, and opened by applying negative pressure. In this case, the plug is pressed against the orifice from the side of a compensation chamber. In the future, however, negative pressures will no longer be available in a motor vehicle. For this reason, to close and open the damping channel orifice, an electric motor pressing the plug against the damping channel orifice from the side of the compensation chamber can be used. Because the pressure in the working chamber can be very high, namely peaking at about 5 bar, however, gears are needed that are capable of pressing the plug against the orifice at such peak pressures. These gears, however, present problems in terms of heat exchange and contamination; these problems can cause defective operation of the support bearing.

SUMMARY OF THE INVENTION

The object of the invention therefore is to reduce greatly the pressing forces with which the plug must be pressed against the damping channel orifice at such peak pressures.

According to the invention, the problem is solved by use of a support bearing which, according to the invention, the plug can be pressed against the damping channel orifice from the direction of the working chamber. By this solution, the plug is pressed against the damping channel orifice at a prevailing pressure in the working chamber. Consequently, a motor actuating the plug can have much smaller dimensions than before and still keep the damping channel orifice closed even at peak pressures. Moreover, it is possible to omit the gear altogether, or also to reduce its dimensions. By omitting the gear, it will be possible to prevent malfunctioning of the support bearing to a great extent in the future.

Because electric energy is available in a motor vehicle when the vehicle is operating, the plug can be actuated by an electric motor.

In a preferred embodiment of the invention, the plug can be actuated by a direct-current motor. Direct-current motors are inexpensive components so that their use contributes to the cost reduction of the support bearing.

In a further development of the invention, the direct-current motor can be equipped with a Hall transmitter. The Hall transmitter takes over the function of path scanning to determine the position of the plug.

In another embodiment, it is also possible to equip the direct-current motor with an inductive displacement sensor capable of taking over the path scanning function.

In yet another embodiment, the plug can be actuated by a stepping motor. With the stepping motor, the position of the plug can be determined without the need for additional components.

Advantageously, the plug is provided with a drive spindle. The plug and the drive spindle can constitute a single piece which reduces the fabrication costs of the support bearing.

When the plug and the drive spindle constitute a single piece, they can be made inexpensively of a plastic material

In another embodiment, however, it is also possible for the plug and the drive spindle to constitute two separate parts, in which case the plug can be screwed onto the drive spindle. Advantageously, the spindle can then be provided with an outer thread and the plug with an inner thread.

The plug can be in the shape of a cone, the tip of which can be inserted into the damping channel orifice. In this arrangement, the plug is centered in the damping channel orifice.

In another embodiment, it is also possible for the plug to be mushroom-shaped. This shape of the plug provides the damping channel with particularly favorable flow characteristics during operation.

In another inexpensive variant of this embodiment, the plug can have the shape of a plate, preferably a round plate.

The plug can advantageously be made of a metal and/or of a plastic material.

When the damping channel is located in the center of a dividing wall disposed between the working chamber and the compensation chamber, vibrations of the highest amplitude can be transmitted.

Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, exemplary embodiments will be explained in greater detail by reference to the attached drawings, in which:

FIG. 1 shows a cross-sectional view of the support bearing according to a principle of the invention; and

FIG. 2 shows a cross-sectional view of a plug according to a principle of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

FIG. 1 shows a support bearing 10 with a working chamber 11 and a compensation chamber 12. Working chamber 11 and compensation chamber 12 are separated from each other by a dividing wall 13. In the dividing wall 13 is located a damping channel orifice 14. The damping channel orifice 14 can be opened and closed with a plug 15. To close the damping channel orifice 14, the plug 15 is pressed against the damping channel orifice 14 from the direction of the working chamber 11. The plug 15 is provided with a drive spindle 16. On the drive spindle 16 is disposed an electric motor 17 intended to actuate the plug 15.

The electric motor 17 can be a direct-current motor or a stepping motor. When the electric motor 17 is a direct-current motor, the motor can be equipped with a Hall transmitter or an inductive displacement sensor for path scanning.

The plug 15 and drive spindle 16 can consist of a single piece of plastic material. It is also possible, however, for a plug 20 and a drive spindle 21 to form a single piece (see FIG. 2). In this case, the plug 20 can then have an inner thread 22 and drive spindle 21 an outer thread 23 so that plug 20 can be screwed onto drive spindle 21.

The plug 15 preferably has the shape of a mushroom. During the operation of the damping channel, the mushroom shape provides especially favorable flow characteristics.

The plug 20, on the other hand, may also have the shape of a cone. The tip of the cone can be inserted into the damping channel orifice 24, wherein the plug 20 is centered in orifice 24. In principle, the plug 20 can have other advantageous shapes such as, for example, the shape of a round plate.

The damping channel orifice 14 is preferably located in the middle of dividing wall 13. In this manner, vibrations of the highest amplitude can be transmitted.

The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

Claims

1. A support bearing comprising: a working chamber; a compensation chamber; and a damping channel that links said working chamber and said compensation chamber; said damping channel being provided with a damping channel orifice that can be opened and closed with a plug; wherein said plug is pressed against the damping channel orifice from the direction of the working chamber.

2. The support bearing according to claim 1, wherein said plug is actuated with an electric motor.

3. The support bearing according to claim 2, wherein said electric motor is a direct-current motor.

4. The support bearings according to claim 3, wherein said direct-current motor is equipped with a Hall transmitter.

5. The support bearing according to claim 3, wherein said direct-current motor is equipped with an inductive displacement scanner.

6. The support bearing according to claim 2, wherein said plug actuated with a stepping motor.

7. The support bearing according to claim 2, wherein said plug and a drive spindle of said electric motor form a single unit.

8. The support bearing according to claim 7, wherein said plug and said drive spindle are comprised of a plastic material.

9. The support bearing according to claim 7, wherein said plug can be screwed onto said drive spindle.

10. The support bearing according to claim 1, wherein said plug is in the shape of a cone.

11. The support bearing according to claim 1, wherein said plug is in the shape of a mushroom.

12. The support bearing according to claim 1, wherein said plug is plate-shaped.

13. The support bearings according to claim 1, wherein said plug comprises a metal and/or a plastic material.

14. The support bearing according to claim 1, wherein said damping channel is disposed in a middle portion of a dividing wall that is located between said working chamber and said compensation chamber.