Primary Piston Recess Layout for Compact Brake Pressure Generators

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing brake pressure generators are bulky and require significant installation space, limiting their integration in vehicles.

Innovation Solution

A primary piston design that integrates the spindle and nut of the brake pressure generator into recesses of the primary piston, reducing the overall length and optimizing the installation space.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the brake pressure generator is designed with conventional separate components, then the structural integrity and functionality are maintained, but the overall length and installation space requirement increase

Engineering Contradiction:
Improveinstallation spaceVSAvoidcomponent integration complexity
Core Design Contradiction:
Volume of moving objectVSDevice complexity

Solution Approach 1:

The patent merges the spindle and nut components directly into the primary piston structure. The spindle is integrated as an axial extension of the primary piston, while the nut is formed as a recess in the primary piston. This combining of previously separate components into a single integrated unit reduces the overall length and installation space of the brake pressure generator.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent implements nesting by placing the nut recess within the primary piston structure, allowing the nut to be formed as a cavity inside the piston body. This nested arrangement enables the spindle and nut to occupy space within the primary piston rather than extending outward, thereby reducing the overall dimensional footprint of the brake pressure generator.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Length of moving object

If the primary piston is designed with integrated spindle and nut recesses, then the overall length of the brake pressure generator is reduced, but the manufacturing complexity of the primary piston increases

Engineering Contradiction:
Improveoverall lengthVSAvoidpiston manufacturing
Core Design Contradiction:
Length of moving objectVSEase of manufacture

Solution Approach 1:

The integration of the spindle and nut into the primary piston creates a combined component that reduces overall length. The spindle is formed as an axial extension and the nut as a recess, both integrated into the piston body during manufacturing, eliminating the need for separate assembly of these components.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent changes the geometric parameters of the primary piston by incorporating axial and radial recesses. These parameter changes allow the spindle and nut to be integrated into the piston structure, reducing the overall length while the recesses are formed using standard manufacturing processes such as machining or molding.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4532280B1Primary piston for a brake master cylinder or transmission device
Publication Date: 2026.02.18 ROBERT BOSCH GMBH
  • EP4532280B1 patent drawingFigure 1
  • EP4532280B1 patent drawingFigure 2

AI summary

The invention relates to a primary piston (10) for a main brake cylinder (14) or a transmission device (26), the primary piston having, on a first side (10a), a first recess (20) into which at least one portion, directed towards the primary piston (10), of a primary spring (12) of a main brake cylinder (14) that is equipped with or cooperates with the primary piston (10) is able to be introduced or is fastened, wherein, on a second side (10b), directed away from the first side (10a), of the primary piston (10) a second recess (28) is formed, into which at least one portion, directed towards the primary piston (10), of a spindle (22) of a transmission device (26) that is equipped with or cooperates with the primary piston (10) and, at the same time, at least one portion, directed towards the primary piston (10), of a nut (24), arranged on the spindle (22), of the transmission device (26) are able to be introduced and/or are fastened, and wherein the first recess (20), formed on the first side (10a) of the primary piston (10), borders at least one portion, directed towards the first side (10a), of the second recess (28).