Industrial Technology Research Institute

Feng Chia University

Jiun-Hung Chen

Hong-Sheng Fang

Hann-Tsong Wang

Ming-Hsin Liu

Chun-Hung Lin

Chen-Der Tsai

Tean-Mu Shen

Jung-Chen Chien

Cheng-Chan Tsai

Ming-Fong Chen

De-Chang Lin

Zhang-Hua Fong

Chien-Yie Tsay

A mechanical metamaterial comprising a chiral structure and a reentrant structure repeatedly layered to form a 3D structure with improved compressive response is disclosed. The 3D structure of the present invention is a metamaterial which can be perfectly and easily produced by a photocuring 3D printing process without any internal support. The introduction of modified carbon nanotubes into the printing composite material improves the compression resistance and impact resistance of the products and increases the service life through the special periodic structure. The application of 3D printing technology in fabricating mechanical metamaterials can break through the processing limitation of traditional processing technology or microelectronics manufacturing technology to make three-dimensional periodic structures.

Mechanical metamaterial with improved compressive responses

A multi-stage vacuum pump includes a plurality of casings connected in series and each casing defining a respective compression chamber, a plurality of partition plates each set in between each two casings. When compressed by rotors at shafts in one compression chamber, compressed air passes through the air path formed in the corresponding partition plate to the next compression chamber for further compression, and finally compressed air passes to the last compression chamber through the air path formed in the last partition plate. Because the invention is designed to let compressed air directly pass through the air path in each partition plate, the outer diameter and volume of the multi-stage vacuum pump can be minimized to reduce the weight and the manufacturing cost.

Multi-stage vacuum pump

The present invention is an electropolishing/grinding device for an inner surface of a long tube, including at least one long tube, one electrode, at least two partitions, one fixed magnet mechanism, one driving apparatus and an axial driven mechanism. The fixed magnet mechanism and the driving apparatus form a magnetic levitation effect, which uses magnetic repulsiveness and magnetic attraction to keep the partitions away from the inner surface and avoid an eccentric situation. One of the two partitions has a plurality of springs, a plurality of protruding objects and a plurality of abrasive devices interconnected and firmly touching the inner surface of the tube for grinding.

Electropolish/grinding means for an inner surface of a long tube

A double screw rotor assembly includes two screw rotors meshed in a bushing inside a casing. The threads of the screw rotors have a constant pitch, and define with the bushing a plurality of air chambers in the pitch. The volumes of the air chambers reduce gradually from the inlet toward the outlet due to reduced tooth height so that the outer diameter defined by the tooth tip of the thread of each screw rotor has the shape of an invertedly disposed cone. An electric driving device is controlled to move the bushing axially in the casing relative to the screw rotors in adjusting the clearance between the inside wall of the bushing and the tooth tip of the thread of each screw rotor, so as to minimize the consumption of starting power and facilitate stable running of the screw rotors, Further, a O-ring is provided at the top wall of the busing and pressed on the casing to keep an airtight status, so as to improve the working efficiency.

Double screw rotor assembly with electrically controlled clearance adjustment means

A power-saving, low-noise double screw rotor assembly, which includes a casing and a pair of screw rotors, wherein the casing has an inside wall defining a compression chamber, an inlet port and an outlet port communicating with the compression chamber. The screw rotors are mounted in the compression chamber and meshed together, each having a spiral thread around the periphery. The thread defines an equidistant pitch. The addendum of the thread defines an outside diameter and is abutted against the inside wall of the casing, the dedendum defines a root diameter. A thread height is defined between the addendum of thread and the dedendum of thread, the thread height gradually reduces in direction from the inlet port toward the outlet port. The dedendum of thread and side walls of the thread of each screw rotor define with the inside wall of the casing at least one transfer chamber having a volume gradually reducing in direction from the inlet port toward the outlet port.

Double screw rotor assembly

Growing community of inventors

Taichung, Taiwan

Jiun-Hung Chen