Hydraulic Cylinder Switching With Piston-Ring End-Position Damping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing two-way hydraulic units for technical machines, such as silo block cutters, face challenges in achieving high operational reliability, requiring minimal maintenance, and being cost-effective while ensuring smooth operation.
Innovation Solution
A two-way hydraulic unit with a double-acting working cylinder and hydraulic control unit, featuring piston rings with adjustable piston ring gaps for end position damping and a hydraulic control system with spring-actuated control valves, allowing for automatic and reliable switching without additional active means or energy sources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a pump is used to provide pressure for a changeover switch, then switching function is achieved, but device complexity and maintenance requirements increase
Solution Approach 1:
The hydraulic system uses its own operating fluid to provide pressure for actuating the changeover switch. The control cylinder utilizes hydraulic pressure from the system's own fluid supply to automatically trigger the switching mechanism, eliminating the need for separate pumps or external power sources for the switching function.
Solution Approach 2:
The hydraulic fluid serves multiple functions: it acts as the working medium for the control cylinder, provides damping through the piston ring gaps, and generates the pressure needed to actuate the changeover switch. This multi-functionality reduces the number of separate components needed in the system.
2Reliability
If additional active means or energy sources are added for control switching, then switching reliability improves, but manufacturing cost and device complexity increase
Solution Approach 1:
The system uses its own operating fluid to provide pressure for actuating the changeover switch. The control cylinder utilizes hydraulic pressure from the system's own fluid supply to automatically trigger the switching mechanism, eliminating the need for separate pumps or external power sources for the switching function.
Solution Approach 2:
The invention uses hydraulic pressure from the system's own fluid to actuate the changeover switch. The control cylinder converts hydraulic pressure into mechanical motion to trigger the switching mechanism, utilizing the existing hydraulic medium rather than adding separate actuation systems.
3Ease of operation
If piston rings with gaps are used for end-position damping, then smooth operation is achieved, but manufacturing precision requirements increase
Solution Approach 1:
The damping effect is achieved by controlling the gap size between piston rings and the cylinder wall. By adjusting this geometric parameter, the system provides end-position damping that ensures smooth operation. The gaps allow controlled fluid leakage that creates a cushioning effect at the ends of the piston stroke.
4Reliability
If higher pressure is applied to achieve reliable switching, then switching reliability improves, but dynamic loads and energy consumption increase
Solution Approach 1:
The system uses its own operating fluid to provide pressure for actuating the changeover switch. The control cylinder utilizes hydraulic pressure from the system's own fluid supply to automatically trigger the switching mechanism, eliminating the need for separate pumps or external power sources for the switching function.
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
Ensures automatic and reliable operation of the piston unit with reduced dynamic loads, preventing undesired loads on the hydraulic unit and connected devices, and allows for smooth movement with lower pressure requirements, enhancing operational reliability and reducing maintenance needs.
Implementation Method 1
The piston has a radially circumferential seal, a first piston ring with a first piston ring gap, and a second piston ring with a second piston ring gap... provides end-position damping
Implementation Method 2
The control valve has a spring element which is relaxed in the passive switching position and tensioned in the active switching position
Implementation Method 3
A fluid, acting as the hydraulic working medium, can be introduced into the two working chambers via the main ports
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a two-way hydraulic unit comprising a double-acting working cylinder (1) and a hydraulic control unit (2), in which: the piston (3) comprises a radially peripheral seal (8), a first piston ring (9) with a first piston ring gap (10) and a second piston ring (11) with a second piston ring gap (12), the first and the second piston rings (9; 11) being respectively axially distanced from the seal (8); the working cylinder (1) has a first main connection (14) and a first control connection (15) in a first axial end position damping region (13), and a second main connection (17) and a second control connection (18) in a second axial end position damping region (16); if the first piston ring (9) overruns the first main connection (14), a partial volume of the fluid is enclosed in a first working chamber (6), and can flow off in a restricted manner via the first piston ring gap (10), and if the second piston ring (11) overruns the second main connection (17), a partial volume of the fluid is contained in a second working chamber (7), and can flow off in a restricted manner via the second piston ring gap (12); and the hydraulic control unit (2) comprises a first and a second hydraulically actuated control valve (19; 20), a hydraulically actuated changeover valve (21), a pressure flow supply line (22), a fluid return line (23), a first and a second main line (24; 25), and a first and a second control line (26; 27).