Abstract: The oil-free screw compressor includes: a screw rotor, a bearing configured to support a rotor shaft, a shaft seal device including an oil seal arranged at a position closer to the bearing and a gas seal arranged on at a position closer to the rotor chamber, an atmosphere communication space communicating with an atmosphere communication hole, and an oil return groove including a return inclined surface inclined so as to expand in diameter radially outward from a gas seal-side end to an oil seal-side end. The oil seal portion is a viscoseal including a spiral groove portion. An inner peripheral surface of the oil seal includes an inner peripheral boundary portion that defines a part of the atmosphere communication space, on a side closer to the bearing in the atmosphere communication hole. The oil seal-side end is arranged in a vicinity of the inner peripheral boundary portion and at a position closer to the bearing.

Abstract: The oil-free screw compressor includes: a screw rotor, a bearing configured to support a rotor shaft, a shaft seal device including an oil seal arranged at a position closer to the bearing and a gas seal arranged on at a position closer to the rotor chamber, an atmosphere communication space communicating with an atmosphere communication hole, and an oil return groove including a return inclined surface inclined so as to expand in diameter radially outward from a gas seal-side end to an oil seal-side end. The oil seal portion is a viscoseal including a spiral groove portion. An inner peripheral surface of the oil seal includes an inner peripheral boundary portion that defines a part of the atmosphere communication space, on a side closer to the bearing in the atmosphere communication hole. The oil seal-side end is arranged in a vicinity of the inner peripheral boundary portion and at a position closer to the bearing.

Abstract: A screw compressor including a driving machine having an output shaft coupled to an input shaft of a compressor main body; a clutch mechanism between the output shaft of the driving machine and the input shaft of the compressor main body; a pressure sensor installed in a discharge channel; and a controller that controls the switching of the clutch mechanism between an engaged state and a disengaged state based on a discharge pressure value detected by the pressure sensor is disclosed. When the discharge pressure value becomes higher than an unload set value that is predetermined, the controller controls the clutch mechanism to be switched to the disengaged state. According to the above screw compressor, power losses are reduced even when the supply of compressed gas is hardly required.

Abstract: An oil separator has a container main body and an flow channel. A partition wall member faces the opening of the flow channel and extends along a wall of the container main body. An upper end member seals the space between the upper end of the partition wall member and the container main body. A side end member seals a space between one side end of the partition wall member and the wall of the container main body. A gap between the partition wall member and the wall of the container main body is narrower than an inner diameter of the flow channel and is largest at an open side end. An outer circumference of the partition wall member is longer than half of the inner diameter of the flow channel and shorter than half of the circumferential length of the inner wall of the container main body.

Abstract: A screw expander system has a condenser positioned for receiving a mixture of oil and operating medium from a screw expander. A pump pressure-feeds the mixture from the condenser to an evaporator where the operating medium is evaporated. An oil separating tank separates the mixture from the evaporator into the gaseous operating medium and the oil, and the operating medium is returned to the screw expander via a throttle mechanism. The oil can thereby be supplied to the screw expander without providing a separate oil pump, as a result of which the screw expander system is compact.

Abstract: A water-lubrication type screw fluid machine has a first non-contact seal, a second non-contact seal and a lip seal disposed between a rotor chamber and a bearing for a rotor shaft. The bearing is located on the high pressure side and in this order from the rotor chamber side. the bearing includes a low pressure communicating channel for allowing an outflow space formed on the rotor chamber side with respect to the first non-contact seal to communicate with a low pressure channel for the target gas communicating with a low pressure space inside the rotor chamber or the rotor chamber, a pressurized communicating channel for introducing high-pressure target gas into a pressurized space formed between the first and second non-contact seals, and an open communicating channel through which an open space formed between the second non-contact seal and the lip seal opens to the outside of the casing.

Abstract: A deposit removing device capable of efficiently removing deposit on a plate-like member such as a metal plate or resin plate by reducing a spacing distance between the plate-like member and an injection nozzle, and also capable of coping with the removal of deposit on the plate-like member rolled or conveyed at a high speed. This deposit removing device removes the deposit adhered to the plate-like member (T) by jetting compressed air from at least one jetting hole (101) of a nozzle body (100) in which the at least one jetting hole (101) is formed. This device is configured so that the nozzle body (100) is supported so as to be movable in a direction (W1) substantially perpendicular to the surfaces (T1 and T2) of the plate-like member (T).

Abstract: In a screw for extruder, a bearing segment having a function of supporting a screw main body at an intermediate part when kneading is performed is provided at a position corresponding to a kneading portion or on the downstream side of the kneading portion. The bearing segment is provided with at least two flights having a sectional shape of a complete meshing type with one streak in the axial direction, the flights are arranged in the rotational direction with uniformly displacing a phase thereof respectively, and length of the flights in the axial direction is set to 0.2D (D: rotational outer diameter of the bearing segment) or more. According to the above configuration, bending of the screw main body is prevented and abrasion of the flights and a barrel is suppressed.

Abstract: Disclosed is a concave reflecting mirror (10) for a heliostat, said concave reflecting mirror being provided with: a reflecting member (11) wherein a mirror surface section (15) is provided on the front surface of a base material (14), the rigidity of the peripheral portion is lower than that at the center, and the mirror surface section (15) can be elastically deformed such that the mirror surface section forms a concave paraboloidal surface; a frame member (12), which supports the peripheral portion of the rear surface (16, 35) of the reflecting member (11); and an adjusting member (13), which is attached to the frame member (12), at a position facing substantially the center of the rear surface (16, 35) or that of the front surface of the reflecting member (11), and which elastically deforms the reflecting member (11) by pulling the rear surface (16, 35) of the reflecting member (11) or pressing the front surface of the reflecting member (11).

Abstract: A groove is provided in the periphery of a pressure receiving area of a pressure receiving surface opposing to the load of axis weight within a bearing surface supporting an axis, and a liquid supply route communicating with the groove is provided so that liquid is supplied to the groove through the liquid supply route. In such a configuration, a bearing having a simple structure and a high compact load capacity and a liquid cooling type screw compressor using the above bearing are provided.

Abstract: An oil-cooled type screw compressor includes shafts mounted on rotors in a casing and extended to two sides of the rotors. Thrust plates rotate with the shafts. The thrust plates are sealed while spacing them from the rotors and define first and second spaces. Thrust bearings are arranged in the first and second spaces. An oil feed passage communicates with the one of the first and second spaces that is located on the side to apply a force against the thrust force to the thrust plates when boosted. An oil discharge passage communicates with the one of the first and second spaces that is located on the side to apply a force against the anti-thrust force to the thrust plates when boosted, to establish the communication between the space inside and an oil discharge target. An oil distribution passage distributes oil between the first space and the second space.

Abstract: A screw expander system includes a screw expander provided with an expansion space for expanding an operating medium, an operating medium inlet, an operating medium outlet, oil inlets, and oil outlets, a condenser which condenses a mixture, sent from the screw expander, of oil and the operating medium, a pump which pressure-feeds the mixture sent from the condenser, and an evaporator which evaporates the operating medium contained in the mixture. The screw expander system circulates and supplies the operating medium sent from the evaporator, to the operating medium inlet, and circulates and supplies the oil sent from the evaporator, to the oil inlets. An oil separating tank which separates the mixture into the operating medium and the oil is disposed between the evaporator and the screw expander, and an oil containing section of the oil separating tank and the oil inlets of the screw expander are connected.

Abstract: A water-lubrication type screw fluid machine has a first non-contact seal, a second non-contact seal and a lip seal disposed between a rotor chamber and a bearing for a rotor shaft. The bearing is located on the high pressure side and in this order from the rotor chamber side. the bearing includes a low pressure communicating channel for allowing an outflow space formed on the rotor chamber side with respect to the first non-contact seal to communicate with a low pressure channel for the target gas communicating with a low pressure space inside the rotor chamber or the rotor chamber, a pressurized communicating channel for introducing high-pressure target gas into a pressurized space formed between the first and second non-contact seals, and an open communicating channel through which an open space formed between the second non-contact seal and the lip seal opens to the outside of the casing.

Abstract: An oil separator has a container main body and an flow channel. A partition wall member faces the opening of the flow channel and extends along a wall of the container main body. An upper end member seals the space between the upper end of the partition wall member and the container main body. A side end member seals a space between one side end of the partition wall member and the wall of the container main body. A gap between the partition wall member and the wall of the container main body is narrower than an inner diameter of the flow channel and is largest at an open side end. An outer circumference of the partition wall member is longer than half of the inner diameter of the flow channel and shorter than half of the circumferential length of the inner wall of the container main body.

Abstract: A screw compressor including a driving machine having an output shaft coupled to an input shaft of a compressor main body; a clutch mechanism between the output shaft of the driving machine and the input shaft of the compressor main body; a pressure sensor installed in a discharge channel; and a controller that controls the switching of the clutch mechanism between an engaged state and a disengaged state based on a discharge pressure value detected by the pressure sensor is disclosed. When the discharge pressure value becomes higher than an unload set value that is predetermined, the controller controls the clutch mechanism to be switched to the disengaged state. According to the above screw compressor, power losses are reduced even when the supply of compressed gas is hardly required.

Abstract: A screw compressor is disclosed wherein a pair of rotor shafts are disposed horizontally and an oil sump is formed at the bottom of a bearing casing which accommodates bearings for supporting the rotor shafts, a bearing lower portion being soaked into oil present in the oil sump for lubrication. The screw compressor comprises a chamber provided separately from the bearing casing, an oil line for communication between the oil sump in the bearing casing and the chamber and oil level detecting means disposed in the chamber. According to this structure, the oil level in the bearing casing can be checked accurately and there is no fear of oil shortage in the bearings.

Abstract: A water-lubricated compressor has a discharge on-off valve in a discharge channel located between a discharge port of a compressor body and a water separating/recovering unit. A water circulation on-off valve is disposed in a water circulation channel located between a water cooler and a water supply portion in the compressor body. A gas release channel provides communication between a gas phase portion of the water separating/recovering unit and the exterior of the water separating/recovering unit. A gas release on-off valve is disposed in the gas release channel. When the compressor body is not in operation, the discharge on-off valve and the water circulation on-off valve are closed and the gas release on-off valve is opened, allowing water to be recovered to the water separating/recovering unit. When there is no demand for compressed gas, it is possible to remove water from the water cooler, which otherwise may be damaged.

Abstract: Provided is an oil-cooled type screw compressor having a compressor body for compressing a suction gas and discharging the compressed gas.

Abstract: In a compressor bearing for supporting a rotor shaft of a compressor, a first oil groove is formed in a bearing surface on the side opposite to a bearing load acting direction, a second oil groove is formed in a position adjacent to the first oil groove in an anti-rotational direction, a first oil channel and a second oil channel communicating with the first oil groove and the second oil groove, respectively, to supply oil to the first and second oil grooves from an exterior, common oil supply source are provided, a circumferential length of the second oil groove is set larger than that of the first oil groove, and a minimum value of a sectional area perpendicular to the longitudinal direction of the second oil channel is set smaller than that of a sectional area perpendicular to the longitudinal direction of the first oil channel. The compressor bearing of such a configuration is small in load induced by oil pressure and exhibits an outstanding rotor shaft cooling effect.

Abstract: In a bearing constituted by a plural-layer slide member, the plural-layer slide member comprises a resin layer of polytetrafluoroethylene as a slide member and a backing strip to which the resin layer is bonded. A fitting hole having a depth exceeding the thickness of the resin layer is formed from the resin layer side. A temperature measuring metallic member formed of a white metal is fitted in the fitting hole. A temperature sensor is positioned within the temperature measuring metallic member. This bearing permits an accurate detection of its temperature. Further, in an oil cooled screw compressor having a bearing lubricating oil supply pipe, a slide surface of the bearing is covered with polyether ether ketone. Even if foaming occurs in the oil, it is possible to prevent the occurrence of a mechanical trouble such as galling.