scholarly journals Characteristics of a Force-balance Nozzle-flapper Type Pneumatic Pressure Control Proportional Valve. Part 2. Output Pressure versus the Output Flow-rate Characteristics.

1995 ◽  
Vol 26 (3) ◽  
pp. 343-349
Author(s):  
Naike CHEN ◽  
Kenji ARAKI
Keyword(s):  
Flow Rate ◽  
Pressure Control ◽  
Force Balance ◽  
Proportional Valve ◽  
Pneumatic Pressure ◽  
Output Pressure ◽  
Output Flow ◽  
Valve Part

A Portable Pneumatic Driving Unit for a Left Ventricular Assist Device

1988 ◽  
Vol 11 (3) ◽  
pp. 186-190 ◽  
Author(s):  
N. Kabei ◽  
E. Shimemura ◽  
Y. Sakurai ◽  
K. Tsuchiya
Keyword(s):  
Flow Rate ◽  
Pressure Sensors ◽  
Left Ventricular ◽  
Pressure Level ◽  
Blood Pump ◽  
Ventricular Assist ◽  
Output Pressure ◽  
Output Flow ◽  
New Type ◽  
Output Characteristics

The authors developed a portable air driving unit for an artificial heart. As the portable energy source of the driver, a commercially available Ni-Cd battery was used. A linear compressor was selected as a portable size compressor. To reduce the number of parts to be assembled, a new type of pneumatic system was employed. In this system, the pressure level was regulated by varying the output flow rate of the compressor instead of using a pressure regulator and large air reservoirs. A one-board microcomputer and pressure sensors were used to control the pressure level. The total weight of the unit is 9.5 Kg. After assembling the components into the portable unit, a blood pump was connected to examine the output characteristics of the system. It was confirmed that the unit could drive the blood pump continuously for more than 2 hours under the following conditions: output flow rate of the blood pump = 5 L/min and output pressure — 100 mmHg.

Study on the Characteristics of a New Type Pneumatic Pressure Regulator

2013 ◽  
Vol 347-350 ◽  
pp. 157-161
Author(s):  
Jun Gong Ma ◽  
Xin Hua Chen
Keyword(s):  
Mechanical Valve ◽  
Pressure Control ◽  
Superior Performance ◽  
Mechanical Pressure ◽  
Pressure Regulator ◽  
Valve Body ◽  
Pneumatic Pressure ◽  
Output Pressure ◽  
Flow Disturbances ◽  
Downstream Flow

ressure regulators are very important elements in pneumatic systems. Purely mechanical pressure regulators are commonly used to control the supply pressure to the desired value. The intelligent pneumatic pressure regulator (IPPR) is designed as the demands of pressure control precision increase. Its prominent advantage is the ability to achieve accurate output pressure, remote control and centralized management. In this paper, the IPPR consists of a mechanical valve body, a stepping motor, a microcontroller, a pressure sensor. Herein, its pneumatic characteristics were analyzed, and the pressure control algorithm was presented. The superior performance of IPPR was shown in AMEsim simulation, especially in terms of avoiding affects from upstream pressure and downstream flow disturbances.

Development of a Novel High Pressure Electronic Pneumatic Pressure Reducing Valve

2010 ◽  
Vol 133 (1) ◽  
Author(s):  
Xu Zhipeng ◽  
Wang Xuanyin
Keyword(s):  
High Pressure ◽  
Flow Rate ◽  
Closed Loop ◽  
Mechanical Design ◽  
Mathematic Model ◽  
Load Flow ◽  
Pneumatic Pressure ◽  
Output Pressure ◽  
Novel Structure ◽  
Pressure Reducing Valve

Pressure reducing valve (PRV) is one of the critical components in high pressure pneumatic systems. Nowadays, manually operated PRVs have been widely used, but there is still no universal electronic PRV. Thus, we proposed a novel high pressure electronic pneumatic pressure reducing valve (EPPRV) whose inlet pressure (pi) is up to 31.5 MPa. The EPPRV mainly consists of a poppet structured pilot valve and a piston structured main valve. A proportional electromagnet was used as the command element, and a pressure closed loop, rather than a force closed loop controller, was designed. First, the mechanical design and functionality of the EPPRV are carefully analyzed. Then, a mathematical model is built up, and the working characteristics of pressure, flow rate, and frequency response are simulated. Finally, the test bench is introduced, and detailed experiments are carried out. Simulated and experimental results are highly consistent within output pressure (po) ranging from 8 MPa to 25 MPa and load flow rate (qld) ranging from 60 g/s to 650 g/s, which verifies the feasibility of the novel structure and the validity of the mathematic model.

scholarly journals Slewing valve based on bypass pressure-compensation principle for dynamic control of large inertia load

2018 ◽  
Vol 10 (8) ◽  
pp. 168781401879434
Author(s):  
Haibo Xie ◽  
Wu Zhu ◽  
Jiujiu Lv ◽  
Liang Hu ◽  
Huayong Yang
Keyword(s):  
Flow Rate ◽  
Dead Zone ◽  
Dynamic Performance ◽  
Dynamic Control ◽  
Flow Distribution ◽  
Proportional Valve ◽  
Rate Fluctuation ◽  
Compensation Principle ◽  
Output Flow ◽  
Pressure Compensation

Typical slewing valve is a three-position six-way proportional valve based on bypass throttle principle, whose output flow rate and opening dead zone of the main valve port are both affected by the load. Thus, it has poor performances in dynamic control of varying loads. This article presents a novel slewing valve based on bypass pressure-compensation principle, which has much better performance in dynamic control of varying loads and even for large inertia loads. A pressure-compensated valve is added to connect the out ports of the main valve port and the bypass port to keep the pressure differences at the main valve port and the bypass port in same. As a result, the flow distribution ratio of these two ports keeps stable for a certain spool position, which can avoid the output flow rate fluctuation despite the varying loads. In addition, the opening dead zone of the main valve port is very small and keeps almost unchanged. These advantages make the proposed valve to control large inertia load with great stability. In the article, a mathematical model formulating the dynamic performance of the valve is further established to provide guide for the optimization of the parameters, including the shapes and orifice areas of the main valve port and bypass port, the stiffness of the spring controlling spool motion, and so on. A prototype valve was manufactured based on the presented method. A series of tests on experiment bench and real crane validate its great performances on flow rate and dead zone stabilities as well as fast dynamic response.

Dimensionless Study on Output Flow Characteristics of Expansion Energy Used Pneumatic Pressure Booster

2012 ◽  
Vol 135 (2) ◽  
Author(s):  
Yan Shi ◽  
Maolin Cai
Keyword(s):  
Mathematical Model ◽  
Flow Characteristics ◽  
Average Output ◽  
Pneumatic Pressure ◽  
Output Pressure ◽  
Output Flow ◽  
Expansion Energy ◽  
Set Up ◽  
Piston Stroke ◽  
The Mathematical Model

To obtain high-pressure gas, air-driven boosters are widely used. In this paper, a new pneumatic pressure booster (named expansion energy used booster, short for EEU booster), which makes use of the expansion power of compressed air in driving chambers is proposed. To set a foundation for the study on optimization of the booster, the basic mathematical model of working processes is set up. By selecting the appropriate reference values, the basic mathematical model is transformed to a dimensionless expression for modeling simulation. In this way, the dimensionless output flow characteristics of the booster can also be found. Through analysis, it can be seen that, first, the dimensionless output flow of the booster is mainly determined by the dimensionless Piston Stroke-set (the piston stroke, when the driving chambers stopped to charge air, is defined to be Piston Stroke-set), the dimensionless output pressure of the booster and the dimensionless area of the piston in the driving chambers, the study on optimization of the booster can be done based on the analysis of the influence of the three dimensionless parameters on the dimensionless average output flow and the efficiency. Lastly, the mathematical model is verified experimentally. This research can be referred to in the design of EEU boosters and the study on optimization of the EEU booster.

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