Actuator Piston Fixing Hole Design for Cylinder Scratch Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In hydraulic pressure control circuits, the existing methods for fixing detection members to pistons can scratch the cylinder's inner surface due to the exposure of caulking metal fittings, especially when the piston is inserted with a specific shape or orientation.
Innovation Solution
An actuator design featuring a piston with a bottomed fixing hole and a stay extending from the piston's exposed portion, where the fixing member is inserted through the hole to secure the detection member, preventing exposure on the piston's surface that contacts the cylinder, thus avoiding scratches.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a through hole is formed in the piston and a rivet is inserted to fix the detection member, then the detection member can be securely fixed to the piston, but the caulking metal fitting may scratch the cylinder's inner surface
Solution Approach 1:
The harmful caulking portion is extracted and separated from the fixing process. Instead of using a through-hole rivet that requires caulking inside the cylinder, the patent uses a bottomed hole configuration where the fixing member is inserted and secured without exposing the caulking metal fitting to the cylinder's inner surface, thus removing the source of potential damage
Solution Approach 2:
A stay is introduced as an intermediary component between the piston and the detection member. The stay extends from the piston's exposed portion to the outside of the cylinder, allowing the detection member to be fixed to the piston through the bottomed hole without direct contact between the fixing member and the cylinder's inner surface
2Ease of manufacture
If the detection member is fixed to the piston in a state where the piston is inserted into the cylinder, then the assembly can be completed in a compact sequence, but the fixing method may cause scratches on the cylinder interior
Solution Approach 1:
The piston is prepared in advance with a bottomed fixing hole formed in its exposed portion before insertion into the cylinder. This preliminary preparation allows the fixing member to be inserted and secured without requiring subsequent operations that could damage the cylinder's inner surface
Solution Approach 2:
The harmful caulking operation is extracted and relocated to occur outside the cylinder. The fixing member is inserted into the bottomed hole and secured with the caulking metal fitting positioned on the exposed portion of the piston, away from the cylinder's inner surface, thus eliminating the scratching risk while maintaining assembly convenience
Data Source
AI summary
An actuator capable of preventing the inside of a cylinder from being scratched is provided. A two-way piston includes a cylinder having an opening, a piston, and a stroke sensor that detects a position of the piston. The stroke sensor includes a stay that extends from a portion exposed from the opening of the piston to the outside of the cylinder, a member to be detected that is attached to the stay, and a sensor that detects a position of the member to be detected. The piston including a fixing hole having a depth smaller than a diameter of the piston in the portion exposed from the opening. The stay is fixed by a bolt that is inserted into the fixing hole.