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PWM Controlled Proportional Equipment

The paper presents an experimental model of PWM controlled proportional pneumatic direction control valve developed by the authors, as well as the functioning of a pneumatic system that incorporates the original solution of valve. The main parameters that control the system can be settled using a software application developed for that purpose.

Theoretical and Experimental Researches Regarding the Performances of a New Type of Rotating Machine with Profiled Rotors

The paper establishes an original computation formula for the flow rate of the fluid transported by a new type of rotating machine with profiled rotors; the theoretical characteristic diagram of the machine - flow rate versus machine speed - is built. The scheme of the test stand used for performing measurements needed in order to build the experimental diagram is presented. The variation of the volumetric efficiency of the working machine in function of the machine speed is finally described.

Theoretical analysis of a pressure setting and control system with PWM direction control valve

The paper tackles theoretical aspects concerning an original automated system that sets and controls the pressure inside a tank chamber of fixed volume. The structure of the system integrates an original device developed and designed by the authors. The device digitally controls the one way flow of the working fluid using pulse width modulation, allowing the free flow in the other way. The purpose of this research stage was the theoretical establishing of the variation law of the pressure inside the controlled chamber.

Proportional Hydraulic Directional Control Valve with Planar Distribution and Differential Control

The paper presents an original solution of hydraulic proportional directional control valve with planar distribution and differential control. The characteristic of the flow section is established and an example of such directional control valve integrated in the structure of a hydraulic positioning system with mechanical feedback is given.

Hydraulic Control of Speed and Position of a Pneumatic Actuator

The paper presents an original pneumo-hydraulic system that controls the speed and the position of the actuated load by using a hydraulic circuit containing a hydraulic proportional throttle. A mathematical model of the solution is developed and numerical simulations are performed. The experimental results obtained on the built model confirm the theoretical ones.

Influence of the Flow Section Geometry on the Static Characteristic Curves of Proportional Hydraulic Throttle Valves

Various constructive versions of hydraulic units found in the structure of proportional hydraulic equipment are analysed in the paper. For each version, the authors establish the variation law of the flow section in function of the position of the adjusting element in relation to the reference position. The approach is useful when a theoretical analysis of a proportional equipment is needed, as well as when the characteristic diagrams of the equipment are theoretically established.

Proportional Hydraulic Flow Control Valves with Simple and Differential Command

The paper brings in an original solution of proportional hydraulic flow control valve, which can function with both simple and differential command. The static adjustment characteristic of this equipment is analyzed. Also, two systems that integrate the discussed equipment are taken into account.

Incremental Pneumo-Hydraulic Positioning Unit

The paper describes the construction of an original linear pneumo-hydraulic positioning unit developed by the authors. The mathematical model that describes the functioning of the unit and the simulation results are also presented.

Fuzzy Multiobjective Optimization Used in Tolerance Synthesis of Mechanisms

Fuzzy objective multioptimization describes performance criteria and constraints in terms of fuzzy membership functions. The membership function of the decision is obtained as conjunction of performance criteria and constraints. A method of allocating tolerance intervals using fuzzy multiobjective optimization is presented for the case of a 3R manipulator. The proposed method is validated through Monte Carlo simulation.

Mechatronic Designed Hydraulic Positioning System

The paper presents the hardware structure of an original hydraulic positioning system based on a mechatronic approach. Dedicated control algorithms are also presented.