This paper describes a development of 5-axis dry electrical discharge machining (dry EDM). The machining characteristics in the processing of a spherical cavity were compared between 3-axis and 5-axis machining in order to investigate the effect of the 5-axis dry EDM. It was found that the processing time of 5-axis machining was nine times shorter than 3-axis machining. Since the end surface of pipe electrode was uniformly worn in 5-axis machining, it was easy to compensate for the tool electrode wear and improve the machining accuracy. Error of the processed shape from the target shape increased when the pitch used in finishing was larger than 60% of the tool electrode diameter due to the edge wear of the tool electrode. Hence, the machining accuracy was improved by optimizing the pitch of the tool path and compensating for the tool electrode wear using the simulation developed.

抄録全体を表示

We are proposing a small electric vehicle which uses a low powered battery (7.2 V, approximately 2 Ah) to be used for shopping by the elderly. For this study, we have developed a standing position ride-type electric vehicle considering easy riding by which the user can select position ride-type. Furthermore, steady running tests were conducted. Then, the noise that the vehicle generate was evaluated. This paper will present the design with respect to easy riding and running performance and present the experimental results.

抄録全体を表示

We are developing a small compact electric vehicle for shopping purposes. In this study, we fabricated an experimental vehicle, that uses only six small rechargeable AA batteries (7.2 V, approximately 2 A·h) as an electric power source. The vehicle user can select between two driving positions: standing and sitting. A compact transmission with a 90-W DC motor and a speed controller that uses pulse width modulation control was designed as an actuating system. Running experiments were conducted to observe the performance of the fabricated vehicle on a flat floor in a gymnasium. The fabricated vehicle was able to operate for 52 min at a speed of 2.73 km/h. The getting-on and getting-off processes in the vehicle were repeated many times during shopping. The human leg strain while getting on and off the vehicle was investigated by electromyogram measurement. During the getting-on and getting-off processes in the vehicle, the myoelectric potential of the quadriceps increased in the sitting position but did not increase in the standing position. The experimental results show that a user suffers more strain in the sitting position than in the standing position.

抄録全体を表示

電動車椅子の主な操作はジョイスティック操作であるが、この操作が困難な人の場合は使用出来ないという問題点がある。よって、自律性を持たせた知的制御によりこの問題点を解決する。そのためには外界の情報を得て周辺環境を認識する必要がある。USBカメラから取得した画像を処理することにより電動車椅子の自律走行制御を行いその有効性を検証する。

抄録全体を表示

The electrochemical corrosion tests of DLC films formed on aluminum substrates by ionization deposition method have been performed to evaluate their ability as a protective coating for electronic devices. In addition, the testing results of DLC/Al obtained in this work have been compared with those of SiO₂/Al and SiN/Al. The main results obtained in this study are as follows; (1) The electrochemical corrosion behavior of DLC/Al becomes considerably similar to that of SiN/Al and different from that of SiO₂/Al. It has excellent anti-corrosion property. (2) Some corrosion pits under the pinhole defects of DLC/Al after potentiodynamic anodic polarization of DLC/Al are linked together. In other words, the morphological character of DLC/Al shows mixed types of SiO₂/Al and SiN/Al. (3) According to the above results, the authors have proposed three type of corrosion models about DLC/Al, SiO₂/Al and SiN/Al, respectively.

抄録全体を表示

The apparatus of mechanochemical turbine in the mechanical shape and materials similar to those designed by A. Katchalsky was constructed. The experiment on the driving of mechanochemical turbine was performed to make clear some obscure points in Katchalsky's paper such as proper condition of crosslinking treatment of collagen film, theoretically induced revolution number and situation of turning.
The following results were obtained; 1) crosslinking of collagen film with 2% formaldehyde aqueous solution and 10M LiBr aqueous solution as a contracting liquid were found to be suitable, 2) the equation of the calculated revolution number using the mechanochemical diagram was induced, 3) this turbine could not be turned continuously for a long period of time, but continuous several turnings were gained temporarily, and it was found that the observed revolution number was 2.5 sec^-1 and the power was 26.5mW closed to the figure of 30mW obtained by Katchalsky. The results indicate that the induced equation of revolution number is valid and the power of 26.5mW would be acceptable.

抄録全体を表示

The classificatory mechanism by pneumatical action at the taker-in cylinder part of the flat carding engine (D-type) consists of centrifugal, curved and climbing air current, so the lints and trashes can be classified by centrifugal force, gravity, inertia force and buoyancy.
As a result of the qualitative investigations using the smoke-stream line, the following were observed:
1. Air current within the limits less than 100mm from the inside of the both frames is to be excluded from the ordinary pneumatical action.
2. As a result of this investigation concerning each variable time, it is possible to regard these streams as the quadric co-ordinatins streams.
An example of the measuring values of the speed of currents concerning the centrifugal currents around the taker-in cylinder and the currents along the back surface of the mote knife, are showed by Fig. 6. As a results of those measuring under the experimental conditions, the following were observed:
1. The tangential velocity of the centrifugal currents V_t is calculated from the following experimental formula;
where, U₀, L_c and h_c are circular velocity of taker-in cylinder, circular length from gauge point between dish plates nose and taker-in cylinder, and distance from surface of taker-in cylinder respectively.
4. V_r, the radial velocity of the centrifugal currents, is calculated from the following experimental formula;
3. V_s, the component of velocity in the direction of the back surface of the mote knife concerning the currents along its back surface, is calculated from the following experimental formula;
where, h, α₂, β₃ and V_??_ are distance from back surface of mote knife, coefficient and exponent concerning circular velocity of taker-in cylinder and length from gauge point of mote knife, and component of velocity in direction of back surface of mote knife on line between centrifugal currents and currents along back surface of the knife.
4. θ_s, the angle to the back surface of the mote knife, of the currents along the back surface of the knife, is calculated from the following experimental formula;
where, k₂ and m₂ are coefficient and exponent concerning circular velocity of taker-in cylinder and length from gauge point of the mote knife.

抄録全体を表示