Master brake cylinder for a hydraulic motor vehicle brake system

Patent metadata

Field	Value
Publication number	US-9969373-B2
Application number	US-201414760804-A
Country	US
Kind code	B2
Filing date	Jan 30, 2014
Priority date	Jan 30, 2013
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A tandem master brake cylinder for a hydraulic motor vehicle brake system, which is impinged upon by a pneumatic brake booster, including at least one piston which is displaceable in a housing and has a plurality of follow-up connections the follow-up connections allowing a hydraulic connection between the pressure chamber and a pressureless follow-up chamber at the start of a braking operation. At least some of the follow-up connections are formed as transverse bores through a wall of at least one piston and are arranged at a same distance relative to the piston edge in a main plane, wherein the overtravel thereof by the sealing collar defines a closure path of the piston. In order to allow a smooth, quiet and yet sufficiently reliable braking initiation, the follow-up connections are arranged in a distributed manner on at least three planes, the planes being arranged at a distance to one another and in parallel to the piston edge.

First claim

The invention claimed is:

1. A master brake cylinder for a hydraulic motor vehicle brake system, which is acted upon by a pneumatic brake booster comprising:
at least one piston, which is movable in a housing and delimits a pressure chamber in the housing has a piston edge directed toward the pressure chamber and is sealed off from the pressure chamber by a cup seal arranged in an annular groove of the housing,
a plurality of replenishing connections is in each case provided in the piston said replenishing connections allowing a hydraulic connection between the pressure chamber and a pressureless replenishing chamber at the start of a braking operation,
wherein at least some of the replenishing connections are formed as transverse bores through a wall of the at least one piston and are arranged at an equal distance relative to the piston edge in a main plane (E 1 ), the crossing of which by the cup seal defines a closure path of the piston and
wherein the replenishing connections are arranged in a manner distributed between at least three planes (E 1 , E 2 , E 3 ) including the main plane (E 1 ), wherein the at least three planes (E 1 , E 2 , E 3 ) are arranged spaced apart parallel to the piston edge.

2. The master brake cylinder as claimed in claim 1 , wherein the replenishing connections are arranged in a manner distributed between at least 4 planes (E 1 , E 2 , E 3 , E 4 ) including the at least three planes (E 1 , E 2 , E 3 ), wherein the at least four planes (E 1 , E 2 , E 3 , E 4 ) are arranged spaced apart parallel to the piston edge.

3. The master brake cylinder as claimed in claim 2 , wherein all the planes apart from the main plane (E 1 ) are arranged offset in the direction of the piston edge relative to the main plane (E 1 ), with the result that they are crossed by the cup seal ( 13 ) before the main plane (E 1 ) when the piston is actuated.

4. The master brake cylinder as claimed in claim 2 , wherein the main plane (E 1 ) has at least 3 replenishing connections.

5. The master brake cylinder as claimed in claim 2 , wherein a second plane (E 2 ) of the at least four planes (E 1 , E 2 , E 3 , E 4 ) has the same number or fewer replenishing connections as/than the main plane (E 1 ).

6. The master brake cylinder as claimed in claim 2 , wherein each plane of the at least 4 planes (E 1 , E 2 , E 3 , E 4 ) has an equal number of replenishing connections.

7. The master brake cylinder as claimed in claim 2 , wherein a cross section of each individual replenishing connection in the main plane (E 1 ) is made the same size as or larger than individual cross sections of the replenishing connections in all the other planes.

8. The master brake cylinder as claimed in claim 2 , wherein a sum of the cross sections of all the replenishing connections in the main plane (E 1 ) is made the same size as or larger than a sum of the cross sections of all the replenishing connections in each individual further plane.

9. The master brake cylinder as claimed in claim 2 , wherein a spacing between the first main plane (E 1 ) and a last plane is in a range between 0.5 mm and 3 mm.

10. The master brake cylinder as claimed in claim 1 , wherein all the planes apart from the main plane (E 1 ) are arranged offset in the direction of the piston edge relative to the main plane (E 1 ), with the result that they are crossed by the cup seal before the main plane (E 1 ) when the piston is actuated.

11. The master brake cylinder as claimed in claim 1 , wherein the main plane (E 1 ) has at least 3 replenishing connections.

12. The master brake cylinder as claimed in claim 1 , wherein a second plane (E 2 ) of the at least three planes (E 1 , E 2 , E 3 ) has the same number or fewer replenishing connections as/than the main plane (E 1 ).

13. The master brake cylinder as claimed in claim 1 , wherein each plane of the at least three planes (E 1 , E 2 , E 3 ) has an equal number of replenishing connections.

14. The master brake cylinder as claimed in claim 1 , wherein a cross section of each individual replenishing connection in the main plane (E 1 ) is made the same size as or larger than individual cross sections of the replenishing connections in all the other planes.

15. The master brake cylinder as claimed in claim 1 , wherein a sum of the cross sections of all the replenishing connections in the main plane (E 1 ) is made the same size as or larger than a sum of the cross sections of all the replenishing connections in each individual further plane.

16. The master brake cylinder as claimed in claim 1 , wherein a spacing between the first main plane (E 1 ) and a last plane is in a range between 0.5 mm and 3 mm.

Assignees

• Continental Teves Ag & Co Ohg

Inventors

• König Harald
• Graichen Kai-Michael
• Krebs Stephan
• Kollers Michael
• Krämer Horst
• Macher Andreas

Classifications

• B60T11/20 Primary

  Tandem, side-by-side, or other multiple master cylinder units · CPC title

• B60T11/236 Primary

  Piston sealing arrangements · CPC title

• B60T11/232 Primary

  Recuperation valves · CPC title