Industrial Technology Research Institute

Cheng-Chan Tsai

Hong-Sheng Fang

Tean-Mu Shen

Hann-Tsong Wang

Ming-Hsin Liu

Tsung-Hsin Lin

Jung-Chen Chien

Jiun-Hung Chen

Ming-Shinn Liou

Ming-Fong Chen

Zhang-Hua Fong

A double screw rotor assembly includes two screw rotors meshed in a bushing inside a casing. The threads of the screw rotors have a uniform 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 output due to the reduce of tooth high 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. Adjustable spring means is provided to impart an axial spring force to the bushing relative to the casing, guide means is provided to guide axial movement of the bushing relative to the casing, and a O-ring is disposed between the top wall of the bushing and the casing. Adjusting the pre-loading of the spring means controls the dimension of the clearance between the inside wall of the bushing and the tooth tip of the thread of each screw rotor. The top wall of the busing forces the O-ring against the casing to maintain an airtight condition, so as to improve the working efficiency.

Double screw rotor assembly having means to automatically adjust the clearance by pressure difference

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

A nozzle device for purging a vacuum pump includes a nozzle, the top portion of the nozzle is a tapered portion, two sides of the tapered portion are installed with nozzle holes for guiding the exhausted air sub-flow to be exhausted from the two sides of vent end.

Nozzle device for purging a vacuum pump

Growing community of inventors

Hsinchu, Taiwan

Cheng-Chan Tsai