Abstract: A scroll fluid machine is disclosed, which comprises a stationary scroll with an embedded wrap which is spiral in form, extending from a central part of a scroll body toward the outer periphery thereof, and a revolving scroll with an embedded spiral wrap engaging with said spiral wrap, the said revolving scroll having a scroll body coupled to a drive shaft 11A coupled to a drive at the central portion thereof. The drive shaft 11A is cooled directly by cooing means provided inside it. The scroll body of the revolving scroll has a central part coupled to a drive. Heat generated in a process, in which fluid sucked from the scroll edge is led to the central part while being progressively compressed, can be removed at the central part which is elevated to a highest temperature, thus permitting efficient cooling of bearings and seal members near the revolving scroll central part and the drive shaft.

Abstract: A double-wrap dry scroll vacuum pump for use as a vacuum pump for nuclear power equipment. The pump has a pump body including a suction port capable of being communicated with a vessel to be evacuated and a discharge port for discharging wrap compressed gas to an outside of the pump body after an operation of gas compression by the progressive volume reduction of a sealed space, formed by a revolving scroll and a pair of stationary scrolls. The pump further includes a pair of enclosing members which cover opposite end portions of a drive shaft and are mounted in a gas-tight state around the revolving scroll. The pump has compressed gas feed ports for feeding compressed gas therethrough to the enclosing members, the compressed gas having a higher pressure than the wrap compressed gas and is discharged together with the wrap compressed gas through the discharge port.

Abstract: A scroll fluid machine is disclosed, which comprises a stationary scroll with an embedded wrap which is spiral in form, extending from a central part of a scroll body toward the outer periphery thereof, and a revolving scroll with an embedded spiral wrap engaging with said spiral wrap, the said revolving scroll having a scroll body coupled to a drive shaft 11A coupled to a drive at the central portion thereof. The drive shaft 11A is cooled directly by cooing means provided inside it. The scroll body of the revolving scroll has a central part coupled to a drive. Heat generated in a process, in which fluid sucked from the scroll edge is led to the central part while being progressively compressed, can be removed at the central part which is elevated to a highest temperature, thus permitting efficient cooling of bearings and seal members near the revolving scroll central part and the drive shaft.

Abstract: An oil-free two-stage vacuum pump includes first and second pump stages coupled in series. The first and second pump stages have discharge spaces capable of communicating with each other via a bypass passage. The bypass passage is provided with a pressure control valve which is closed when pressure in the bypass passage is lower than a predetermined pressure. This permits a reduction in scroll size. In addition, the pump is free from problems present in pumps with large scroll sizes such as drive shaft vibrations due to warping thereof at high speed rotation, noise and heat generation, and durability reduction due to causes such as non-uniform contact between stationary and revolving scrolls. Moreover, in a compression step in the first pump stage, withdrawn gas is under high pressure; the gas pressure in a sealed vessel is close to the atmospheric pressure in an initial stage of driving.

Abstract: A scroll fluid machine includes stationary scrolls, with embedded wraps which are spiral in form, extending from central parts of scroll bodies toward the outer peripheries thereof, and a revolving scroll, with an embedded spiral wrap, engaging with the spiral wraps. The revolving scroll has a scroll body coupled to a drive shaft coupled to a drive at the central portion thereof. The drive shaft is cooled directly by a cooling structure provided inside it. The scroll body of the revolving scroll has a central part coupled to a drive. Heat generated in a process, in which fluid sucked from the scroll edge is led to the central part while being progressively compressed, can be removed at the central part which is elevated to a highest temperature, thus permitting efficient cooling of bearings and seal members near the revolving scroll central part and the drive shaft.

Abstract: It is sought to provide an oil-free scroll vacuum pump, which can discharge condensed fluid in it to the outside. An oil-free scroll vacuum pump body 1 for withdrawing fluid from a vessel to be evacuated, compressing the fluid and discharging the compressed fluid to the outside, comprises a stationary scroll constituted by a housing half 4 and a wrap 7, another stationary scroll constituted by a housing half 5 and a wrap 6, and a revolving scroll 3. The housing half 4 has a gas ballast gas inlet duct 10 and an inlet port 4a, and the revolving scroll 3 has a communication hole 3e. Gas is introduced through the inlet port 4e into a sealed space defined by wraps of the individual scrolls engaged with one another. The introduced gas is compressed together with compression fluid in the sealed space, and the resultant fluid is discharged through a discharge port 4c to the outside.

Abstract: The present invention is intended to provide an oilless scroll-type compressor which can obtain a high compression efficiency with highly accurate sealability retained and particularly has such a constitution that a chip seal fitted in each of the wrap end surfaces of stationary scrolls and an orbiting scroll is integrated with a backup seal, a discharge port in communication with a wrap groove terminal end through a through-hole is formed in a land section positioned on the interior side of a wrap inner circumferential end on the side of one scroll and situated around a shaft hole through which a main shaft is inserted, and the circumference of said discharge port is surrounded by the chip seal extended from said wrap.

Abstract: A scroll-type fluid machine has an orbiting scroll with involute wraps projecting axially on each of opposite sides, a pair of stationary scrolls each with involute wraps which mate with the wraps of the orbiting scroll, and a main shaft inserted in a central axis hole of the stationary scrolls for driving the orbiting scroll in orbital movement. The internal ends of the wraps of the stationary scrolls are extended inwardly to an outer peripheral wall of a land part where the central axis hole is formed. The stationary scroll wraps are extended about a half turn longer than the wrap of the orbiting scroll and the internal ends of the wraps are almost in contact end to end at a desired phase during the orbiting movement of the orbiting scroll.