Design and Fabrication of Micro Pump for Functional Fluid Power Actuation System

Fig. 14.1 Concept of micro fluid power actuation system
In this chapter in order to realize micro fluid power actuation systems, a high performance micro pump module using functional fluids is proposed, fabricated, and experimentally investigated. A prototype model of micro pump module for
Various actuation principles, for example piezoelectric, electrostatic and thermal expansion have already been reported for the micro actuation system [2]. However, fluid power actuation system has a great potential to realize large output power density comparing to the conventional actuation system under the microscopic environment [3]. In conventional fluid power actuation system, however, there are many mechanical parts in the system, for example valves for actuator control and pumps for power source.
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Yutaka TANAKA and Shinichi YOKOTA
dream because of development of micro processing and fabrication technologies. In 1989 gear trains and motors on a wafer have been firstly reported by using the semiconductor micro fabrication technology in U.S.A [1]. Semi-conductor processing technology applied to these fabrications has touched off since the latter half of 1980's, and the research specialized in microscopic environment has begun to be paid to attention rapidly all over the world. There are many micro integrated elements such as micro mirrors and acceleration sensors applied to the semiconductor manufacturing process for the practical use. These elements are made on the flat surface of the silicon wafer with fine fabrication and high integration.
Chapter 14
Design and Fabrication of Micro Pump for Functional Fluid Power Actuation System
Yutaka TANAKA1 and Shinichi YOKOTA2
Abstract A prototype model of micro pump module for micro fluid power actuation systems is fabricated and experimentally investigated. The functional fluid; ECF (Electro-Conjugate Fluid) is used to be pumping function for the micro pump module of the fluid power actuation system. The fluid power source using the ECF can be embedded in the main body of the micro fluid power actuation systems and can be effective as driving source of the actuator. Some kind of a novel needletype of micro electrode in the pump module is fabricated by a micro electric discharge machining. The shape and gap of the electrodes on the delivery pressure of the pump due to the ECF jet are experimentally investigated. The pressure due to the ECF jet strongly depends on the number and shape of the needles and the gap of the electrodes.
Design and Fabrication of Micro Pump for Functional Fluid Power Actuation System 155
micro fluid power actuation systems is fabricated and experimentally investigated. The functional fluid; ECF (Electro-Conjugate Fluid) is used to be pumping function for the micro pump module of the fluid power actuation system. The fluid power source using the ECF can be embedded in the main body of the micro fluid power actuation systems and can be effective as driving source of the actuator. Some kind of a novel needle-type of micro electrodes in the micro pump module is fabricated by a micro electric discharge machining. The shape and gap of the electrodes on the delivery pressure of the pump due to the ECF jet are experimentally investigated.
1 Yutaka TANAKA Faculty of Engineering and Design, Hosei University, Fujimi, Chiyodaku, Tokyo 102-8160, Japan E-mail: y_tanaka@hosei.ac.jp 2 Shinichi YOKOTA Precision & Intelligent Laboratory, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 226-8503, Japan E-mail: syokota@pi.titech.ac.jp
14.2 o-Conjugate Fluid
The electro-conjugate fluids (ECF) recently developed by Otsubo and Edamura [4] are dielectric functional fluids having high insulation. The ECF occurs the strong jet flow that is impressed high electrical voltage of direct from a positive electrode to a negative electrode inserted into the fluid. The phenomenon is well known as one of the electrodynamics effects. The ECF can directly convert electric energy into kinetic energy of the fluid without mechanical moving parts. It is able to be a much attractive approach for applications in novel micro pump devices [5, 6, 7]. In our previous study a small planar pump using the ECF as driving source of the actuator has been fabricated [8].
Our final goal is to develop a new micro fluid power actuation system with accumulating, integrating, miniaturizing and high performance on one single-chip as shown in Fig.14.1. The system consists of four modules, a signal and sensor module, a pump module, a valve module, and an actuator module. This is all-in-one design and fabrication unit consisting of the actuator, the valve, the pump and the sensor modules and functions.