Commercial Vehicle Disc Brake Hold-Down Clip Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing disc brake designs for commercial vehicles face challenges in simplifying the assembly and disassembly process, requiring deformation of elastic elements and costly threaded holes, which complicates the prestressing of hold-down springs and leads to potential oblique wear of brake pads.
Innovation Solution
The design incorporates a hold-down clip with a first projection axially supported on the hold-down spring in a second axial direction, and a second holder that absorbs the reaction force, eliminating the need for additional spring elements and simplifying assembly by using projections or pins that do not require deformation, and optionally incorporating a self-tapping external thread for secure attachment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If latching tongues are used to secure the hold-down clip, then the brake pad is held securely, but assembly and disassembly require deformation of elastic elements which complicates the process
Solution Approach 1:
The invention extracts the elastic deformation requirement from the assembly process by using a snap-fit connection between the hold-down clip's engagement projection and the corresponding recess in the brake caliper. This eliminates the need to deform elastic latching tongues during assembly, simplifying the process while maintaining secure holding through the geometric interlocking of the projection and recess features.
2Strength
If threaded holes are used for attaching the hold-down bracket, then secure attachment is achieved, but manufacturing costs increase
Solution Approach 1:
The invention replaces expensive threaded hole manufacturing with a cost-effective snap-fit connection using molded-in projection and recess features. The hold-down clip includes an engagement projection that fits into a corresponding recess in the brake caliper, eliminating the need for costly threaded fasteners while maintaining secure attachment through the geometric interlocking design.
3Reliability
If additional spring elements are added to secure the hold-down clip, then axial movement is prevented, but device complexity increases
Solution Approach 1:
The invention merges the functions of the hold-down clip and the securing mechanism into a single integrated component. The hold-down clip itself includes an engagement projection that provides the securing function, eliminating the need for separate spring elements or additional securing components. This integration prevents axial movement while reducing overall device complexity.
4Ease of operation
If the hold-down spring is not properly prestressed, then assembly is simpler, but brake pad tilting and oblique wear occur
Solution Approach 1:
The invention incorporates preliminary prestressing of the hold-down spring through the snap-fit connection mechanism. The engagement projection fits into the recess in a predetermined prestressed state, ensuring the brake pad is properly positioned and prevented from tilting during operation. This preliminary action maintains reliability while keeping assembly simple through the self-contained snap-fit design.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution simplifies the assembly and disassembly process without the need for special tools or costly threaded holes, reduces manufacturing costs, and prevents tilting play and oblique wear of brake pads by prestressing the hold-down spring effectively.
Implementation Method 1
a hold-down spring (16, 18) that is pretensioned by the hold-down bracket (20) in the radial direction
Implementation Method 2
the hold-down clip (20) has a first projection (36) which is supported axially on the hold-down spring (16, 18) in a second axial direction
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a disc brake, more particularly for commercial vehicles, comprising a brake calliper (10), at least one brake pad (12, 14), a hold-down spring (16, 18) that holds the brake pad down in the radial direction relative to a brake axis, a hold-down bar (20) that biases the hold-down spring in the radial direction, a first retainer (22, 24) on the brake calliper (10) that supports the hold-down bar (20) radially outwardly, and a second retainer (28, 30) with a stop on the brake calliper (10) that supports the hold-down bar (20) radially outwardly but not in the axial direction, wherein the first (22, 24) or the second (28, 30) retainer has a stop (32, 34) that acts in a first axial direction. According to the invention the hold-down bar (20) has a first projection (36) which is supported axially against the hold-down spring (16) in a second axial direction opposite to the first axial direction, and/or a second projection (38) which is supported in the second axial direction but not radially outwardly against the brake calliper (10).