Tapered Swashplate Axial Piston Pump for Variable Split Displacement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hydraulic systems with single rod hydraulic cylinders face challenges in compensating for the difference in oil volumes at the rod side and cap side of the cylinder, requiring complex hydraulic circuits or specialized three-port pumps that must match the actuator and pump displacement ratios, limiting design simplicity and operational stability.
Innovation Solution
A variable split displacement ratio axial piston machine with a tiltable tapered swashplate that adjusts the relative piston stroke lengths between working sections, allowing for a variable split displacement ratio and simplifying the design by eliminating the need for complex hydraulic circuits or specialized pumps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a single rod hydraulic cylinder is connected to a bi-directional fixed displacement pump, then efficiency is improved by avoiding hydraulic directional/throttling valves, but design complexity increases due to the need to compensate for different oil volumes at rod side and cap side
Solution Approach 1:
The pump is divided into two distinct working sections: a first working section with pistons connected to the cap side of the cylinder, and a second working section with pistons connected to the rod side. Each section has its own set of cylinder bores and pistons, allowing independent displacement control to compensate for the volume difference caused by the piston rod.
Solution Approach 2:
The pump housing serves multiple functions by containing both the first and second working sections within a single integrated structure. The shared driveshaft and housing provide a universal platform that eliminates the need for separate pumps or complex valve assemblies, thereby reducing overall system complexity while maintaining efficiency.
2Reliability
If a three-port asymmetric pump is used to match the hydraulic cylinder, then operational stability is improved, but adaptability decreases because the pump must be specifically built for a certain hydraulic cylinder
Solution Approach 1:
The pump incorporates variable displacement capability through adjustable swashplates or tilting mechanisms in each working section. This allows the displacement ratio between the first and second working sections to be dynamically adjusted to match different hydraulic cylinder configurations, providing both operational stability and adaptability without requiring custom-built pumps for each application.
3Adaptability or versatility
If complex hydraulic circuits with valves and control componentry are used to compensate for volume differences, then design flexibility is improved, but device complexity increases
Solution Approach 1:
The pump integrates the functions of two separate fixed displacement pumps into a single variable displacement unit with two working sections. By combining the displacement control mechanisms and housing within one assembly, the invention eliminates the need for external hydraulic circuits, valves, and control componentry, thereby reducing complexity while maintaining design flexibility through adjustable displacement ratios.
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
The solution provides a flexible and efficient pump design that compensates for volume differences without requiring complex hydraulic circuits or specialized pumps, enhancing design simplicity and operational stability.
Implementation Method 1
a tapered swashplate disposed around said rotatable driveshaft, said tapered swashplate having first and second outer faces that face in axially opposing directions along the longitudinal axis in facial planes of non-parallel relation to one another that are separated by an acutely oblique taper angle measured between said first and second outer faces, the tapered swashplate being adjustably tiltable into different working positions of varying orientation relative to the longitudinal axis of the rotatable driveshaft
Data Source
AI summary
A variable split displacement ratio axial piston machine, featuring a rotatable driveshaft, a tapered swashplate disposed around said rotatable driveshaft, a first working section disposed on a first side of the tapered swashplate, and a second working section disposed on a second side of the tapered swashplate. Each working section includes a respective set of pistons slidably received in a respective set of cylinder bores to draw and expel fluid into and from said cylinder bores. The first and second working sections respectively interface with first and second outer faces of the tapered swashplate in respective first and second facial planes. Tiltable adjustment of a working position of the tapered swashplate is operable to adjust respective orientations of the facial planes, which dictate relative piston stroke lengths of the piston sets. Such tiltable adjustment imparts control over a variable split displacement ratio between the working sections.