Shun Yoshihama

Powder conveyance experiments with peristaltic conveyor using a pneumatic artificial muscle

In recent years, powdered materials have been often used in various industries. Among the various uses of powders, we focused on the conveyance of the developer in the printers. Screw conveyors are commonly used in the printer for the conveyance of the developer. However, this presents the problems such as the condensation of the developer by the shearing force and the temperature rise. Thus, low shear and high-speed conveyance at a low temperature is required. In an alternative approach, we developed a transport device that mimics the intestinal tract and demonstrated successful transport of the highly viscous and solid-liquid mixed fluids. In this study, to overcome the above problems, we considered the peristaltic conveyor. We investigated the ability of this conveyor to convey powder by using the expansion of the rubber. In this work, we performed conveyance experiments by using the carrier used in the printer and measured the weight to determine the conveyance performance per unit of time. By measuring the changes in the conveyance amount due to the changes of the motion interval time, we determined the condition for obtaining the maximum conveyance amount. We then determined the conveyance amount per unit time for the developer.

Mixing of solid propellant by peristaltic pump based on bowel peristalsis

In recent years, the demand for rocket launching has increased due to the development of space technology. However, using inexpensive rockets is not always possible. Although the cost of solid-propellant rockets is relatively reasonable, safely manufacturing a large amount of solid propellant is difficult, and the manufacturing process is disjointed. Therefore, safe and continues manufacturing of solid propellant is necessary. On the basis of the movements of the intestinal tract, we realized that the movements required for transport and mixing of solid propellants are possible to achieve without the application of a large force. By mimicking these intestinal movements, we can safely and continuously manufacture a large amount of solid propellant. We developed a peristaltic pump, based on bowel peristalsis, using straight-fiber-type artificial muscle, and in this study, we demonstrate the usefulness of this pump for transporting the highly viscous fluids and solid-liquid mixed fluid. We consider that the peristaltic pump can also be effectively used as a mixing device. In this paper, we show that mixing one highly viscous fluid with another is possible by measuring the luminance values. In the manufacturing process, we use glass beads with the same diameter as microparticles and a sodium polyacrylate aqueous solution resembling a high viscosity fluid or hydroxyl-terminated polybutadiene as the raw material in the solid propellant. We then measure the glass beads in the resulting solid-liquid mixed fluid.

Triangular cross-section peristaltic conveyor for transporting powders at high speed in printers

ABSTRACT Powder-based materials are widely used in various applications such as printing. In printing, low shear force and high-speed conveyance at low temperatures are required to prevent creating defects in materials. In a previous study, we developed a transportation device based on the human intestinal tract that successfully transported highly viscous and solid–liquid fluid mixes and powder material. In this study, we developed a tubular peristaltic conveyor capable of transporting powdered materials in a printer under the aforementioned conditions. The conveyor had a triangular cross-sectional area and a small air chamber to facilitate high-speed peristaltic motion. The performance of the conveyor was confirmed experimentally, and we achieved a conveyance rate of 81.5 g/s. GRAPHICAL ABSTRACT