High-Pressure Fuel Pump Protective Cap Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing high-pressure fuel pumps in common rail injection systems face challenges in assembly reliability, noise emission, and corrosion due to the complex design of protective caps, which require precise alignment and can lead to incorrect reassembly and visual corrosion issues.
Innovation Solution
A ring-shaped protective cap with a continuous clearance slot is designed to be mounted over the plug with a lateral line connection, allowing for easy installation without disassembling the electrical connection, providing noise and thermal protection while made from non-metallic materials to prevent corrosion and ensure functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a protective cap with multiple recesses is used to cover connections, then the connections are protected, but the device complexity increases and precise alignment is required
Solution Approach 1:
The patent extracts the cable connection from the pump assembly by using a separate connector that can be attached independently. The protective cap then only needs to cover the pump components, not the cable connections, simplifying its structure and eliminating the need for multiple precisely aligned recesses.
Solution Approach 2:
The protective cap is designed as a modular component that can be installed separately from the cable connector. This segmentation allows the protective cap to have a simpler, continuous structure without requiring complex recesses for cable management, while still providing adequate protection for the pump components.
2Object-affected harmful factors
If the protective cap requires precise alignment with multiple recesses, then connections are covered, but assembly reliability decreases due to potential incorrect reconnection
Solution Approach 1:
The cable connection is extracted as a separate, independently attachable component. This allows the protective cap to be installed without any alignment requirements, as it only needs to cover the pump body and not accommodate cable connectors. The connector can be attached afterward without affecting the protective cap installation.
Solution Approach 2:
Instead of designing the protective cap to accommodate the cable connection (as in prior art), the patent inverts the approach by designing the connector to be independently attachable to the pump body, with the protective cap serving only its protective function. This reversal of the design logic eliminates alignment issues and improves assembly reliability.
3Ease of manufacture
If the pump cylinder head is made of bare metal without corrosion protection, then manufacturing is simpler, but the appearance deteriorates and corrosion occurs
Solution Approach 1:
The patent uses a protective cap made of a material that forms a protective shell over the bare metal pump cylinder head. This thin film-like covering protects the metal surface from corrosion and improves appearance without requiring complex corrosion protection treatments on the pump head itself, maintaining manufacturing simplicity.
4Object-affected harmful factors
If the protective cap covers the cable connection, then protection is provided, but installation complexity increases due to disassembly requirements
Solution Approach 1:
The cable connection is extracted as a separate component that does not need to be covered by the protective cap. The connector is designed to attach directly to the pump body in a location that is either inside or outside the protective cap's coverage area, allowing both components to be installed independently without disassembly or complex coordination.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The invention relates to a high-pressure fuel pump (1), in particular of a common rail injection system of an internal combustion engine, having a pump cylinder head (3), having an intake valve (6) arranged in the pump cylinder head (3) in the direction of a pump cylinder axis, and a high-pressure fuel outlet (5) arranged laterally on the pump cylinder head (3), wherein a protective cap (10, 10a) at least partly covering the high-pressure fuel pump (1) is provided. According to the invention, a high-pressure fuel pump (1) having a protective cap (10, 10a) is provided, in which the protective cap (10, 10a) can be mounted without difficulty on an assembled high-pressure fuel pump (1). This is achieved in that a plug (8) having a lateral lead connection (9) is placed on the electrically operated intake valve (6), and the protective cap (10) is formed in two pieces and has two protective cap parts (11a, 11b) that can be fitted to each other, or else in that a plug (8) having a lateral lead connection (9) is placed on the electrically operated intake valve (6), and the protective cap (10a) is formed annularly and has a free clearance slot (19) interrupting the ring.