WO2012035098A2

WO2012035098A2 - Brake actuation unit for a motor vehicle brake system and motor-pump unit for providing a vacuum for a brake actuation unit of a motor vehicle brake system

Info

Publication number: WO2012035098A2
Application number: PCT/EP2011/065997
Authority: WO
Inventors: Michael Wirtz; Holger Marschner; Rudolf Platzer; Martin Semsch; Marin Christov
Original assignee: Continental Teves Ag & Co. Ohg
Priority date: 2010-09-15
Filing date: 2011-09-15
Publication date: 2012-03-22
Also published as: DE102011082749A1; EP2616298A2; KR20130102069A; CN103108788A; WO2012035098A3

Abstract

The invention relates to a brake actuation unit 1, 1', 1'' for a motor vehicle brake system, comprising a vacuum brake booster (2) and a motor pump unit (3) which is provided for supplying a vacuum and comprises a pump connected to the vacuum brake booster (2) and an electric motor driving the pump. According to the invention, an additional sound absorbing element 4, 4', 4'' is provided in the connection between the vacuum brake booster (2) and the pump in order to lower the sound level in the vehicle interior.

Description

Brake actuation unit for a motor vehicle brake system and motor-pump unit for providing negative pressure for a brake actuation unit of a motor vehicle brake system

The invention relates to a brake actuation unit for a motor vehicle brake system with a

A vacuum brake booster and a negative pressure provided for motor-pump unit comprising a pump connected to the vacuum brake booster and an electric motor driving the pump according to the

The preamble of claim 1 and a motor pump unit for providing negative pressure for a

Brake actuation unit of a motor vehicle brake system according to the preamble of patent claim 8.

To provide vacuum (vacuum) for a

pneumatic brake booster, whose interior is in

At least one vacuum chamber and a working chamber is divided, vacuum pumps are used, which suck in the residual air from the vacuum chamber and expel into the atmosphere. In the

Automotive industry are usually this

Vane pumps or swing vane pumps used. These have inherent friction and must be lubricated to achieve an acceptable life. from

The combustion engine of the motor vehicle driven vacuum pumps with wings are therefore connected to the oil circuit of the

Internal combustion engine connected. Nevertheless, one must

significant proportion of the output from the engine power to drive such a pump. And this even if the vacuum in the evacuated Chamber is already fully formed. Therefore, it is useful to operate the vacuum pump with electrical energy and only turn on when the absolute pressure in the vacuum chamber rises above a predetermined value.

Furthermore, in vehicles with electric or hybrid drive, the vacuum pump is not or temporarily not by the

Internal combustion engine are driven. Therefore, electrically powered vacuum pumps are used in these vehicles.

Such an electrically driven pump with a

To equip lubricant circuit or connect to such, would mean a disproportionate effort. Thus come for use in motor vehicles with brake systems with electrically driven vacuum pump only dry-running vacuum pumps in question. In vane pumps, the self-lubricating graphite material is used, from which the wings are manufactured with the required precision at great expense. Therefore, the efforts

to use for providing electrical brake vacuum, a diaphragm pump.

A generic brake actuation unit with a motor pump unit is known for example from DE 10 2007 005 223 AI. From the automotive industry are very high

Requirements relating to the acoustic comfort of

Motor vehicle components provided and demanded by the suppliers robust, durable pumps with very low noise emissions. To meet these requirements, the exhaust ports are in the known motor-pump unit in the

Work space covers and arranged in the pump housing such that displaced from the work spaces air in one, the

Crank drive surrounding the interior of the pump housing becomes. Further, an air outlet unit is provided which a low-noise blowing out of the air from the interior

Redirecting the air allows. The interior, also called the crankcase, serves as a sound-damping room, since the blown air is not passed directly into the atmosphere. By redirecting the air in the air outlet unit, the

Noise level are also significantly reduced, so that Ausblasgeräusche are almost avoided.

During operation of the motor-pump unit, however, it may also come in the vacuum hose to unwanted noise, which are amplified by the brake booster and transmitted to the vehicle interior.

Also by the increased use of vehicles with

Electric drive continue to increase the acoustic requirements, which are made to the brake actuation unit or to the motor pump unit.

It is therefore an object of the present invention to provide a

To provide brake actuation unit with a motor-pump unit or a motor-pump unit, which take into account the increasing requirements in terms of acoustic comfort.

This object is achieved for a

Brake control unit and a motor-pump unit of the specified type with the characterizing features of

Claims 1 and 8 solved.

Other features, advantages and applications of the invention will become apparent from the dependent claims and the following description of several embodiments with reference to

Drawings forth. It shows very schematically:

Figure 1 is a circuit diagram of a first embodiment

a brake actuation unit according to the invention and a motor-pump unit according to the invention;

Figure 2 is a circuit diagram of a second embodiment of a brake actuating unit according to the invention and a motor-pump unit according to the invention and

Figure 3 is a circuit diagram of a third embodiment of a brake actuating unit according to the invention and a motor-pump unit according to the invention.

Fig. 1 shows a brake operating unit 1 for a

Motor vehicle brake system with a

Vacuum brake booster 2 and provided for the provision of negative pressure motor-pump unit 3. The motor-pump unit 3 comprises a connected via a connecting line 6 to the vacuum brake booster 2 pump and a pump driving electric motor.

The pump not shown in detail, for example, as a diaphragm pump with a pump housing and at least one

Working diaphragm provided, which limits a work space with a working space and which is movable by means of a crank drive, wherein the working space with an inlet channel

Inlet valve and an outlet channel is associated with exhaust valve.

Ideally, the pump is designed as a double diaphragm pump with two opposing working diaphragms.

To meet the high demands of car manufacturers to the acoustic comfort of the motor-pump unit account, the outlet channel is arranged arranged such that displaced from the working space air is passed into a surrounding the crank drive interior of the pump housing, wherein an air outlet unit is provided, which

allows low-noise blowing out of the air from the interior.

During operation of the motor-pump unit 3, however, it may also come in the connecting line 6 between the pump and vacuum brake booster 2 to unwanted noise, which are amplified by the vacuum brake booster 2 and transmitted to the vehicle interior.

In particular, due to the increased use of vehicles with electric drive, which are set to the brake actuation unit 1 and to the motor-pump unit 3

Acoustic requirements.

In order to meet these increasing requirements in terms of acoustic comfort, in the all embodiments described below in the connection between the vacuum brake booster 2 and the pump to lower the sound pressure level in the vehicle interior is another

Noise damping element 4,4 ^λ , 4 ^{λ λ} provided, which is either integrated directly in the pump at the vacuum inlet or a vacuum connection 5 of the pump or in accordance with an unillustrated from execution form.

By integrating the further sound damping element 4,4 ^λ , 4 ^{λ λ} in the pump can advantageously account for a separate attachment to the motor-pump unit 3 or another vehicle component.

By the arrangement of the further sound attenuation element

4.4 ^λ , 4 ^{λ λ} at the vacuum port 5 of the pump can in the Connection line 6 Pressure pulsations and vibrations or resulting noises can be avoided.

As can be seen in FIG. 1, according to the first

Embodiment as a further sound damping element 4, a pressure equalization tank 7 is provided, which a

Average magnification of the connecting line 6 allowed. Due to this average magnification may arise

Pressure pulsations and vibrations are largely eliminated.

Fig. 2 shows a second embodiment of a

brake actuating unit 1 ^λ according to the invention. As can be seen, here has the further

Sound attenuation element 4 ^{λ in} addition to a Helmholtz resonator 8. With the Helmholtz resonator 8 are the disturbing

Frequency components absorbed while the surge tank 7 converts the remaining energy of the sound waves on the friction in heat.

An alternative disclosed embodiment of FIG. 3 provides that the further sound attenuation element 4 ^{λ λ} additionally

Capillary tube 9 has. By the

Cross-sectional changes to be flowed through

Connecting line 6, the disturbing frequency components can be absorbed. LIST OF REFERENCE NUMBERS

1 brake actuation unit

1 ^λ brake actuation unit

1 ^{λ λ} brake actuation unit

2 vacuum brake booster

3 motor pump unit

4 further sound attenuation element

4 ^λ further sound attenuation element

4 ^{λ λ} further sound attenuation element

5 vacuum connection

6 connection line

7 pressure equalization tank

8 Helmholtz resonator

9 capillary tubes

Claims

claims

1. brake actuation unit (1.1 ^λ , 1 ^{λ λ} ) for a

Motor vehicle brake system with a

Vacuum brake booster (2) and a for

Providing vacuum motor-pump unit (3), comprising one with the

Vacuum brake booster (2) connected pump and an electric motor driving the pump, the pump as a diaphragm pump with a pump housing and

is provided at least one working diaphragm, which limits a working space with a working space and is movable by means of a crank drive, wherein the

Working space is associated with an inlet channel with inlet valve and an outlet channel with outlet valve and the outlet channel is provided arranged such that displaced from the working space air in a

Crankcase surrounding interior of the pump housing is passed, wherein an air outlet unit is provided, which allows a low-noise blowing out of the air from the interior, characterized in that to reduce the sound pressure level in the vehicle interior in the connection between the vacuum brake booster (2) and the pump another silencer element

(4,4 ^λ , 4 ^{λ λ} ) is provided.

2. brake actuation unit (1,1 ^λ , 1 ^{λ λ} ) according to claim 1,

characterized in that as another

Sound attenuation element (4.4 ^λ , 4 ^{λ λ} )

Pressure equalization tank (7) is provided.

3. brake actuating device (l ^ according to claim 2, characterized in that the further sound damping element (4 ^λ ) additionally comprises a Helmholtz resonator (8).

4. brake actuation unit (1 ^{λ λ} ) according to claim 2, characterized in that the further sound damping element (4 ^{λ λ} ) additionally comprises a capillary tube (9).

5. brake actuation unit (1.1 ^λ , 1 ^{λ λ} ) according to one of

preceding claims 1 to 4, characterized in that the further sound attenuation element (4,4 ^λ , 4 ^{λ λ} ) is arranged directly on a vacuum inlet of the pump.

6. Brake actuation unit according to one of the preceding

Claims 1 to 4, characterized in that the further sound attenuation element is arranged in the pump.

7. brake actuating unit (1, 1 ^λ , 1 ^{λ λ} ) according to claim 1, characterized in that the pump is provided as a double diaphragm pump with two opposite working membranes, which is clamped between a pump housing and a working space cover and thereby the

Limited working space and which are movable by means of the eccentric and connecting rods crank drive.

8. Motor-pump unit (3) for providing negative pressure for a brake actuation unit (1,1 ^λ , 1 ^{λ λ} ) one

Motor vehicle brake system with a

A vacuum brake booster (2), comprising a pump and an electric motor driving the pump, the pump being provided as a diaphragm pump having a pump housing and at least one working diaphragm defining a working space with a working space cover and being movable by means of a crank drive, wherein the

Workspace an inlet port with inlet valve and a Outlet channel is associated with exhaust valve and the outlet channel is arranged arranged such that displaced from the working space air in one, the

Crankcase surrounding interior of the pump housing is passed, wherein an air outlet unit is provided, which allows a low-noise blowing out of the air from the interior, characterized in that a further sound attenuation element (4,4 ^λ , 4 ^{λ λ} ) is arranged directly on a vacuum inlet of the pump ,

9. motor-pump unit (3) according to claim 8, characterized

characterized in that a pressure equalization tank is provided as a further sound damping element (4,4 ^λ , 4 ^{λ λ} ).

10. Motor-pump unit (3) according to claim 9, characterized

characterized in that the further sound damping element (4 ^λ ) additionally comprises a Helmholtz resonator (8).

11. Motor-pump unit (3) according to claim 10, characterized

characterized in that the further sound damping element (4 ^{λ λ} ) additionally comprises a capillary tube (9).