89 results about "Gerotor" patented technology

Disclosed in the present invention are a dual three-phase asymmetric stator-type double-permanent-magnet vernier electric motor and an improved model predictive current control method therefor. The electric motor comprises a stator core, stator permanent magnets, a rotor core and a rotor ferrite, wherein the stator core is formed by alternately arranging umbrella-shaped armature teeth and quasi-rectangular armature teeth in the circumferential direction, the stator permanent magnet, which is magnetized radially outwards, is adhered to each of openings on two sides of the umbrella-shaped armature teeth, and a fan-shaped auxiliary slot is formed between the umbrella-shaped armature teeth and the stator permanent magnet; and the shape of the rotor core is similar to a gear, the rotor ferrite is embedded in the rotor core using a Halbach-based alternating-pole array, and the length of the rotor ferrite is greater than the length of the rotor core and the length of the stator core. In addition, the present invention uses a model predictive current control system based on a virtual voltage vector to construct a cost function to select the voltage vector having the minimum switching frequency, and make same operate preferentially. The present invention not only improves the torque density of the electric motor, but also significantly reduces switching losses in model predictive control.

The invention discloses a face gear dynamics analysis method considering hybrid thermal elastohydrodynamic lubrication and microtexture coupling, which comprises the following steps: step 1, based on a gear dynamics theory, constructing an eight-degree-of-freedom face gear-rotor system dynamics model; 2, establishing a finite element analysis model of the micro-texture face gear transmission pair, solving time-varying meshing stiffness and coupling the time-varying meshing stiffness to a system kinetic equation; 3, coupling a micro-texture item representing the film thickness equation with the film thickness equation of mixed thermal elastohydrodynamic lubrication; 4, coupling the mixing and thermal influence with the elastohydrodynamic lubrication basic equation, and establishing a mixed thermal elastohydrodynamic lubrication model; 5, carrying out iterative solution on the mixed thermal elastohydrodynamic lubrication and micro-texture coupling equation, outputting the tooth surface friction force and the friction coefficient of a solution domain, and inputting the tooth surface friction force and the friction coefficient as parameters into a system kinetic equation; and 6, solving the coupled system kinetic equation by using a Runge-Kutta numerical integration method to obtain the kinetic response of the face gear transmission system.

This invention relates to the field of retarder technology, and more particularly to a hydraulic retarder. The hydraulic retarder includes a housing, a rotor shaft, a stator, a rotor, and a flow disruptor. The housing has a cavity, and the rotor shaft rotatably passes through the cavity, with a drive gear at one end extending out of the cavity. An external splined gear is located at the end of the rotor shaft within the cavity. The stator is fixedly mounted on the housing and fitted onto the rotor shaft, with the stator blades sealingly extending into the cavity. The rotor is located within the cavity and meshes with the external splined gear for transmission. The rotor is rotatably fitted onto the stator, and the rotor blades are fixedly clearance-fitted with the stator blades to form a working chamber. The flow disruptor is retractably positioned within the fixed gap between the stator and the rotor. The flow disruptor extends into the working chamber after the hydraulic retarder exits operation or exits the working chamber when the hydraulic retarder enters operation. This shortens the response time for entering and exiting operation, and reduces the no-load loss of the hydraulic retarder through the flow disruptor.

An electric drive module and an electric drive equipment are provided, the electric drive module comprises a housing, a force output assembly, a flexible gear, a rotor, a stator, a wave generator, and a cooling pipe, the stator is configured to drive the rotor to rotate relative to the housing, when the rotor rotates, the wave generator drives the flexible gear to deform to drive the rigid gear to rotate, at least part of the cooling pipe is received in and closes to the stator. The electric drive module is compact and space saving, the flexible gear is secured to the housing, the rotation of the rigid gear driven by the deformation of the flexible outputs power, which is low rotational inertia and decreases vibration, the cooling pipe arranged in the stator can directly dissipate heat from the stator with high heat dissipation efficiency.

The invention provides a rotor engine. The rotor engine comprises a shell, a main shaft, two main shaft gears, a limiting shaft and two rotor gears, wherein the main shaft is rotatably arranged on the shell in a penetrating mode, and the two main shaft gears, the limiting shaft and the two rotor gears are contained in the shell. The two main shaft gears are sequentially sleeved on the main shaft along the axial direction of the main shaft; the limiting shaft is parallel to the spindle; the two rotor gears are sequentially arranged in the axial direction of the limiting shaft, each rotor gear comprises an outer gear ring and a rotor hinge, the outer gear rings are meshed with the main shaft gear, and working holes are formed in the outer gear rings; the rotor hinge is located in the working hole and connected with the outer gear ring, and the rotor hinge is rotationally arranged on the limiting shaft in a sleeving mode; one part of the rotor hinge extends along the axial direction of the limiting shaft so as to extend into the working hole of the other rotor gear to divide the working hole into four working cavities; the working cavity can drive the rotor gear and the main shaft gear to rotate through the rotor blade by burning and acting, so that friction loss among the main shaft gear, the rotor gear and the shell is effectively avoided, and the sealing performance of the rotor engine is guaranteed.

A kind of converging type pressure increasing gerotor pump.This application relates to the improvement of gerotor internal gear pump structure.By staggered compensation, avoid the flow pulsation caused by pump cavity volume change, and then realize the output pressure boost, and run smoothly.This application includes high pressure pump body, low pressure pump body and main shaft, the axis of outer rotor A and outer rotor B is arranged on one side of the main shaft, the axis of high pressure pump outer rotor is arranged on the other side of the main shaft, and the axis of outer rotor A is + alpha angle relative to horizontal line, the axis of outer rotor B is - alpha angle relative to horizontal line, alpha = 360 ° / 2N, N is the number of inner rotor teeth.This application adopts the ingenious design of rotor eccentric installation, realizes the pressure boost of pump, and the staggered compensation solves the flow pulsation caused by pump cavity volume change, provides stable flow for high pressure booster pump inlet.This application can be widely used in new energy vehicles, wind power, air conditioning, generator, industrial production, chemical industry, petroleum, metallurgy, water treatment and other fields, for conveying various liquids.

A single shaft suspension system includes right and left dampers, first and second hydraulic circuits, a first pressurization mechanism in fluid communication with the first and second hydraulic circuits, and a second pressurization mechanism connected in series with the first pressurization mechanism. The first pressurization mechanism is a cycloid pump and provides roll control by generating a pressure difference between the first hydraulic circuit and the second hydraulic circuit, which raises the fluid pressure in the first working chamber of the right damper and the second working chamber of the left damper. Or hydraulic pressure within the first working chamber of the left damper and the second working chamber of the right damper to provide stiffness against roll of the vehicle while turning. The second pressurization mechanism regulates static pressure within the first hydraulic circuit and the second hydraulic circuit by adding hydraulic fluid to and removing hydraulic fluid from the first hydraulic circuit and the second hydraulic circuit.

The utility model discloses an integrated type swing cycle pump lubricating device, including pump casing, inner rotor and outer rotor, be provided with oil cavity and with oil inlet and oil outlet of oil cavity communication on the pump casing, its characterized in that, the bottom of oil cavity is provided with annular unloading groove with oil outlet communication, and the bottom surface of annular unloading groove is multistage step surface. This integrated type swing cycle pump lubricating device can effectively buffer fluid resistance and pulsation, reduce cavitation and cavitation erosion phenomenon, and stabilize oil pressure of oil outlet.

The invention relates to a liquid pump driven by a PMDC motor and a motor control system and method.The liquid pump comprises a pump shell used for being connected with the PMDC motor, an upper cover connected with the pump shell and provided with an opening allowing liquid to circularly enter and exit, and a shaft seal used for being connected with a driving shaft of the PMDC motor in a sleeving mode and arranged in the pump shell; the inner gear rotor is arranged in the pump shell and used for being connected with the driving shaft, the outer gear rotor is eccentrically connected with the inner gear rotor in a sleeved mode, and the first sealing ring and the second sealing ring are connected to the upper cover and the pump shell in a clamped mode respectively. The liquid pump can be driven by the PMDC motor, liquid can be effectively prevented from entering the PMDC motor through multi-position sealing design, and the liquid pump can be applied to various cooling systems and lubricating systems; meanwhile, the PMDC motor is controlled to enter a low-power, low-current and low-voltage cold start mode in a mode of gradually increasing the input power, potential safety hazards can be effectively avoided, and the service life of equipment is prolonged.

A gerotor pump (10) with an inner rotor (12) and a rotatably supported outer rotor (14), and characterized in that the outer rotor (14) is elastically supported in its axial direction and is pre-tensioned towards the inner rotor (12).

The application discloses a forward and reverse clock movement, which comprises a shell, an MCU controller, a transmission structure, a first coil motor, a second coil motor and a rotor magnet which are arranged in the shell; the transmission structure comprises multiple-stage gears which are sequentially and mutually meshed, and a gear for being connected with a pointer is a pointer gear; the rotor magnet is fixedly connected with a first-stage gear of the multiple-stage gears; the MCU controller inputs a first driving pulse current into a first coil of the first motor coil to generate a magnetic field so as to make the first-stage gear rotate, and further make the pointer gear rotate forward; the MCU controller inputs a second driving pulse current into a second coil of the second motor coil to generate a magnetic field so as to make the first-stage gear rotate, and further make the pointer gear rotate reversely. When time needs to be corrected, a direction with a small rotation amplitude of the pointer is selected to be adjusted forward or reversely, so that the time can be corrected more quickly and accurately.

The invention relates to an automatic blind installation device for a multistage cycloid pump rotor. A rotor clamping assembly comprises a supporting frame capable of ascending and descending, and clamping fingers are arranged in the supporting frame; a detection sleeve is arranged at the lower end of the supporting frame, the lower ends of the clamping fingers are inserted into the detection sleeve, an optical fiber sensor is arranged on the inner wall of the detection sleeve, and a rotor limiting seat is arranged at the lower end and provided with a limiting seat through hole aligned with the optical fiber sensor; the shell is arranged on the shell positioning assembly, the detection sleeve and the rotor limiting seat are firstly driven by the supporting frame to enter the shell, then the shell is driven by the shell positioning assembly to rotate, a blind hole in the bottom of the shell is detected through the optical fiber sensor to determine a to-be-assembled position, and after the shell rotates to the to-be-assembled position, the detection sleeve and the rotor limiting seat are fixed. The detection sleeve and the rotor limiting base are driven by the supporting frame to be separated from the shell, then the upper end of a rotor shaft in the middle of the rotor penetrates through the rotor limiting base and then is clamped through the clamping fingers, and a rotor pin shaft on the edge of the rotor is aligned with a limiting base through hole. During assembly, the rotor can be directly inserted into the shell to realize blind assembly.

A tissue removal device includes a housing, a motor, a motor gear, a rotor gear and an inner tube assembly. The motor, disposed within the housing, is configured to rotate and includes a motor shaft. The motor gear, disposed within the housing, is rotatably coupled to the motor shaft. The rotor gear, disposed within the housing, is rotatably coupled to the motor gear. The inner tube assembly includes an inner shaft rotatably coupled to the rotor gear and having a first blade provided at a distal end of the inner shaft. In response to the rotation of the motor, the inner shaft and the first blade are configured to rotate. The inner shaft is partially disposed outside the housing, and the inner shaft and the first blade are non-detachable from the housing.

The invention belongs to the technical field of hydraulic transmission, and particularly discloses a cycloid hydraulic motor meshing pair performance testing device which comprises a base, an upper supporting plate and a sliding block guide rail frame. The inner side of the loading gear ring is fixedly connected with a needle column fixing seat, and a plurality of needle columns are circumferentially distributed on the inner side of the needle column fixing seat; the upper supporting plate is rotationally connected with a cycloidal gear through a cycloidal gear shaft, and the cycloidal gear is meshed with the needle column; the driving motor drives the loading gear ring through the loading gear shaft; a load torque sensor and a driving motor torque sensor are respectively mounted on the cycloidal wheel shaft and the loading gear shaft; and a rotating speed sensor and a cycloidal wheel test strain gauge are further mounted on the cycloidal wheel shaft. According to the invention, a modular design is adopted, dynamic contact characteristics, frictional wear and fatigue performance data can be accurately obtained, and an efficient and energy-saving test means is provided for design optimization of the cycloid motor and the cycloid speed reducer.

The utility model discloses an interoperable gear rotor pump, which comprises a pump body provided with a first cavity, a second cavity, a feed port and a discharge port; the driving assembly comprises a first transmission shaft, a second transmission shaft and a driving part, and the first transmission shaft and the second transmission shaft are parallel and rotatably arranged on the pump body in a penetrating mode; one end of the first transmission shaft penetrates through the first cavity and is sleeved with a first transmission gear; one end of the second transmission shaft penetrates through the first cavity and is sleeved with a second transmission gear; the first transmission gear is meshed with the second transmission gear; the driving part is in driving connection with the first transmission shaft; the first meshing piece is located in the second cavity and is in key connection with the first transmission shaft; the second meshing piece is located in the second cavity, is in key connection with the second transmission shaft and is used for being meshed with the second meshing piece; the oil injection nozzle is arranged on the pump body and communicates with the first cavity. The problem that the production cost is increased due to the fact that different types of gear pumps or rotor pumps are selected to meet actual requirements in the prior art is solved.

The invention relates to a pump device 100 and a rotor core 711 for the pump device. The pump device 100 comprises a first rotor element 1 rotatably mounted about a first axis of rotation d1 extending in an axial direction Z, a second rotor element 2 rotatably mounted about a second axis of rotation d2 offset from the first axis of rotation d1, and a pump housing 3. The rotor elements 1 and 2 are arranged in a pump chamber 4 bounded by the pump housing 3 and mesh together to convey fluid from an inlet of the pump device to an outlet of the pump device 100. One of the rotor elements 1 and 2 is designed as an outer rotor. The other of the rotor elements 1 and 2 is designed as an inner rotor enclosed by the outer rotor perpendicular to the axial direction Z.The pump housing 3 comprises a pot-shaped first housing part 31, which has a housing base 311 and a circumferential housing wall 312, and has a second housing part 32 arranged on the housing wall 312, wherein the first rotor element 1 is mounted on a retaining part 5 which is arranged in the pump chamber 4 on the housing base 311, wherein the second rotor element 2 is mounted on a side of the pump chamber 4 opposite the retaining part 5 in the axial direction Z.

According to the gear rotor engine, power output is achieved through an air suction gear rotor set, an acting gear rotor set and an ignition device, the air suction gear rotor set has the air suction and compression functions, the acting gear rotor set has the acting and exhaust functions, the ignition device can work in cooperation with an air inlet valve, the gear rotor engine is used in intermittent combustion acting occasions, the combustion efficiency is high, and the service life is long. The engine can be independently ignited to do work without arranging an air inlet valve, is used in a continuous combustion work occasion, is high in output rotating speed, and is high in transmission efficiency due to the fact that the thrust direction and the force arm of detonation gas are not changed all the time.

1. The name of the design product: Integrated hub-connected cycloidal hydraulic motor (WT series). 2. The use of the design product: For medium-tonnage tracked vehicles. 3. The design points of the design product: In shape. 4. The picture or photo that best indicates the design points: Figure 1.

The utility model relates to the technical field of mechanical conveying oil pumps, in particular to a parallel cross type duplex cycloid pump, which is internally provided with parallel cross type pump body cavities, and loop cavities of two pump bodies are optimized into one pump body, so that the duplex cycloid pump with two sets of inlet and outlet loops on one pump body is realized. The length space of the stacked duplex cycloid pump is only one half of that of an existing stacked duplex cycloid pump, the installation space is greatly reduced, the use requirement of a compact space can be met, and the demand quantity of products is increased. According to the parallel cross type duplex cycloid pump, the eccentric direction of the outer rotor of each set of pump faces the upper direction and the lower direction, the radial thrust of the liquid medium in the pump body on the pump shaft faces the left direction and the right direction, and most of the radial thrust in the two different directions counteracts mutually; the radial thrust applied to the pump shaft in the operation process of the liquid medium in the pump shaft is greatly reduced, abrasion caused by extrusion of the radial thrust in the same direction to related parts is greatly reduced, and the overall service life of the cycloid pump is prolonged.

A gerotor pump includes an outer gerotor having an opening defined by an inner surface thereof, an inner gerotor received within the opening of the outer gerotor with a plurality of cavities formed between the inner gerotor and the outer gerotor, and a plurality of first pockets with each of the first pockets formed as an indentation in the inner surface of the outer gerotor. Each of the first pockets forms a first pressure relief feature for preventing an overpressure within each of the cavities formed between the outer gerotor and the inner gerotor.

The utility model discloses a cycloid hydraulic horse BM1-25 displacement structure which comprises a motor shell, a motor rotor is arranged in an inner cavity of the motor shell, the left end of the motor rotor is fixedly connected with a motor output shaft, a fixing base is arranged below the motor shell, the top of the fixing base is connected with an adjusting platform in a sliding mode, and the adjusting platform is connected with a motor output shaft. An alignment assembly is arranged in an inner cavity of the fixing seat and comprises a worm, a rotating column is arranged in the inner cavity of the fixing seat, a worm gear is fixedly connected to the center of the surface of the rotating column, and the worm gear is meshed with the worm. The alignment assembly is arranged to drive the adjusting platform to move at the top of the fixing seat to align the motor output shaft, and then the locking assembly is arranged to propel the motor shell, so that the motor output shaft can be accurately and stably fixedly connected with a stress shaft or a coupler, and the motor output shaft can be accurately and stably connected with the stress shaft or the coupler. Therefore, the purposes of simple and rapid adjustment and accurate and firm alignment can be achieved.

A geared motor (1) is constituted of an axial gap motor unit (2) and a planetary gear reduction unit (3), and has a base section (4) and an output section (5), wherein: the motor unit (2) has a stator (2a), a rotor (2b), and a motor shaft (2c) that rotates integrally with the rotor (2b); the reduction unit (3) has a sun gear (3a) that rotates integrally with the motor shaft (2c), a planetary gear (3b) having a first gear section (3b1) that meshes with the sun gear (3a) and a second gear section (3b2) that rotates integrally with the first gear section (3b1), a first internal tooth gear (3c) that meshes with the first gear section (3b1), and a second internal tooth gear (3d) that constitutes the output section (5) and meshes with the second gear section (3b2); the rotor (2b) has a plurality of permanent magnets (2b1); and the stator (2a) has a plurality of coils (2a1) and an insulating material (2a2) that is integrally molded so as to connect the plurality of coils (2a1) into a single unit, and has a bearing (6) that is mounted on an inner peripheral edge section of the stator (2a) and supports the motor shaft (2c).

The invention discloses a modeling method, system, equipment and medium for gear rotor system dynamics, and the method comprises the steps: adding first kinetic energy, second kinetic energy and third kinetic energy corresponding to a small gear and a large gear to obtain total kinetic energy; the first strain energy, the second strain energy and the third strain energy corresponding to the small gear and the large gear, the bearing boundary condition potential energy, the first constraint potential energy, the second constraint potential energy, the third constraint potential energy and the elastic potential energy formed by gear tooth meshing are added, and the total potential energy is obtained; the total kinetic energy and the total potential energy are substituted into a Lagrange equation for calculation, a control equation is obtained, and gear rotor system dynamics modeling is achieved. According to the method, by comprehensively considering the flexibility of the wheel body and the flexibility of the transmission shaft, the dynamic modeling of the gear rotor system can be better improved, so that the constructed dynamic model of the wheel rotating subsystem has stability and reliability.

A pump system (20) comprising a gerotor pump, comprising: a housing (34) defining a surface; and an idle wheel (32), a rotor (30) defining a surface, wherein a surface clearance (50) is defined between the surface and the surface (44), wherein the surface clearance (50) is variable in its extent and determines the desired performance characteristics of the pump system (20), wherein the housing (34) comprises a first material selected to have a first thermal expansion property, wherein the rotor (34) comprises a second material selected to have a second thermal expansion property, wherein the first thermal expansion property and the second thermal expansion property provide the desired performance characteristics of the pump system, wherein the first thermal expansion property and the second thermal expansion property comprise a greater expansion of the rotor (30) than that of the housing in response to increasing temperature, wherein the first thermal expansion property and the second thermal expansion property result in the surface clearance (50) being opened when the temperature decreases and the surface clearance (50) being closed when the temperature increases, comprising a motor coupled to the rotor (30), wherein the first thermal expansion property and the second thermal expansion property comprise a targeted increase in the surface clearance (50) with decreasing temperature in order to minimize the torque requirements of the motor, wherein the first thermal expansion property and the second thermal expansion property comprise a targeted maximization of the volumetric efficiency of the pump system (20) with increasing temperature, where: the housing (34) defines a cavity, wherein the rotor (30) is arranged in the cavity, the cavity is closed by a cover (36) defining a second surface, the rotor (30) comprises the surface facing the surface of the housing and a second surface facing the second surface, a first gap is defined between the surface and the surface of the housing (34), a second gap is defined between the second surface and the second surface, and the surface clearance (50) is a sum of the first gap and the second gap, wherein the housing (34) is made of steel and the rotor (30) and the idler wheel (32) are made of aluminum.

Pump with multiple gerotors (102), comprising: a shaft (104, 204) rotatable about an axis; a first gerotor pump (108, 208) comprising a first inner gerotor (116, 216) rotatably mounted on the shaft (104, 204); a second gerotor pump (110, 210) comprising a second inner gerotor (118, 218) axially offset from the first inner gerotor (116, 216) and non-rotatably mounted on the shaft (104, 204); a housing (112, 212) comprising: an inlet channel (120, 220) of the first gerotor pump (108, 208) and an outlet channel (124, 224) of the first gerotor pump (108, 208); an inlet channel (122, 222) of the second gerotor pump (110, 210) and an outlet channel (126, 226) of the second gerotor pump (110, 210); and a reservoir (114, 214), wherein the outlet channel (124, 224) of the first gerotor pump (108, 208) and the inlet channel (122, 222) of the second gerotor pump (110, 210) are in fluid communication with the reservoir (114, 214), characterized in that the pump further comprises an electric pump motor (128, 228) for rotating the shaft (104, 204), wherein the first gerotor pump (108, 208) is a scavenging pump for transporting oil from an outlet (130, 230) of a hybrid module (132, 232) to the reservoir (114, 214); and the second gerotor pump (110, 210) is a cooling circuit pump for transporting the oil from the reservoir (114, 214) to a cooling circuit (134, 234) of the hybrid module (132, 232).

Gerotor pump (50) comprising the following: a pump housing (52) that defines a chamber (56) and has a fluid inlet (58) and a fluid outlet (60), an outer gear element which is supported for rotation within the chamber (56) about a first axis (98), wherein the outer gear element has a series of internal teeth (96), and an inner gear element rotatably supported within the outer gear element about a second axis (70) spaced apart from the first axis (98), wherein the inner gear element defines a series of external teeth (86) between which a series of external pockets (106) is inserted, wherein the inner gear element forms a continuous fluid passage (160) to fluidically connect two non-adjacent pockets (106) and another pocket (106) independently of the fluid passages (160), wherein the fluid passage (160) is designed to disrupt harmonics during operation in order to reduce pressure ripples and associated tonal noise.

An electric pump unit (400) comprising: an electric motor assembly (402); an inverter (401) coupled to the motor assembly; at least one inlet; and an outlet; wherein the electric pump unit is configured to: pump oil from an oil sump through the at least one inlet and a gerotor assembly; cool the inverter by immersing the inverter in the oil; and pump the oil to at least one vehicle system external to the electric pump unit. A method for operating such an electric pump unit.

The invention relates to a gear wheel rotor device having at least two gear wheel rotor stages, wherein each gear wheel rotor stage comprises an inner rotor which rotates around an inner axis during operation, has radially outwardly projecting teeth, and an outer rotor which rotates around an outer axis which is radially offset relative to the inner axis during operation, has radially inwardly opening tooth gaps in which the teeth of the inner rotor engage during operation, wherein the tooth gaps are sealed relative to one another and / or relative to the surrounding area. Simplified and cost-effective production of the rotor device and compact design and reliable operation are achieved in that the rotor body comprises the radially opening tooth gaps of the first gear wheel rotor stage and the radially outwardly projecting teeth of the second gear wheel rotor stage, wherein the tooth gaps are sealed relative to one another and / or relative to the surrounding area. Furthermore, the invention relates to a pump device having such a gear wheel rotor device and to a motor vehicle having such a pump device.

The present invention provides a rotary heat pump that can be further miniaturized in response to the current situation. As a solution, a rotary heat pump (100) is provided, which comprises: a rotary drive unit (60), which has a rotating shaft (10), a fixed gear (15), a rotor (20), a rotor housing (30), a first side housing (40) and a second side housing (50), wherein the rotor (20) has a rotor gear (24) meshing with the fixed gear (15) and performing eccentric rotation, the rotor housing (30) follows an epicycloid curve defined by the eccentric rotation of the rotor (20), and the first side housing (40) covers the rotor (20). A rotor housing (30) is covered at one end thereof, a fixed gear (15) is fixed to the first side housing (40), and a second side housing (50) covers the other end thereof; heat exchange fins (70) are respectively arranged in a compression region (32) having the smallest plane area and an expansion region (34) having the largest plane area, which are divided by the rotor (20) and the rotor housing (30); and a heat insulating portion (80) is formed at a boundary portion between the compression region (32) and the expansion region (34).