Abstract: A pump apparatus (1) for use in mobile means of transport (100) such as semitrailers, tank trailers, tank semitrailers (101), tank trucks and trucks (102), has a drive motor (40) and a rotary piston pump (2) having two rotor units (10, 20) on rotatably mounted rotor shafts (11, 21), connected to rotor gear wheels (12, 22). A drive pinion (32) of a drive shaft (31) coupled to one of the rotor gear wheels (12) and is received in a recess (81) of the motor shaft (41).

Abstract: A pump and method for pumping a gas are disclosed. The pump comprises a rotor and a stator. At least one of the rotor or stator comprises at least one liquid opening configured for fluid communication with a liquid source. The liquid opening is configured such that in response to a driving force exerted on liquid from the liquid source a stream of liquid is output from the opening, the stream of liquid forming a liquid blade between the rotor and the stator, gas confined by said stator, said rotor and said liquid blade being driven through said pump from a gas inlet towards a gas outlet.

Abstract: A rotary pump, preferably a vane cell pump or a pendulum slider pump, includes a stator and a rotor which rotates about a rotational axis within the stator. The rotor includes multiple delivery elements which move radially in relation to the rotational axis, and two adjacent delivery elements limit a delivery cell together with the outer surface area of the rotor and the inner surface area of the stator. At least two delivery cells, preferably two adjacent delivery cells, exhibiting a first maximum cell volume form a first delivery cell group and at least two other delivery cells, preferably two other adjacent delivery cells, exhibiting a second maximum cell volume form a second delivery cell group. The first maximum cell volume of the delivery cells of the first delivery cell group is larger than the second maximum cell volume of the delivery cells of the second delivery cell group.

Abstract: A compressor, more particularly, a scroll compressor provides structures that may enhance centrifugal stiffness at a contact point between a fixed scroll and an orbiting scroll. The compressor may include an orbiting scroll having an orbiting scroll wrap wound around a radial-direction inner area from a radial-direction outer area; and a fixed scroll having a fixed scroll wrap wound around the radial-direction inner area from the radial-direction outer area. A surfacing part may be configured to narrow a distance between the orbiting scroll wrap and the fixed scroll wrap may be formed in a predetermined section of the orbiting scroll or fixed scroll wrap.

Abstract: A vane cell pump, including: a delivery chamber having an inlet and an outlet; a rotor which is arranged in the delivery chamber and has a rotor body and vanes which are accommodated by the rotor body such that they can be shifted radially; an end-facing wall which delineates the delivery chamber on an axial end-facing side; and a supporting element which is arranged axially between the end-facing wall and the rotor body and which supports the vanes at their radially inner vane ends, wherein the rotor body, the supporting element and each two vanes which are adjacent in the circumferential direction of the rotor form chambers, the volume of which varies when the rotor is rotating. A pressure equalization connection fluidically connects at least two of the chambers to each other.

Abstract: A scroll compressor is disclosed, which comprises an auxiliary discharge path capable of sufficiently making sure of a discharge area at an initial discharge stage. The compressor comprises a fixed scroll including a fixed end plate portion and a fixed wrap, and an orbiting scroll including an orbiting end plate portion and an orbiting wrap, wherein a discharge hole is formed in the fixed end plate portion, and an auxiliary discharge path for connecting a side of the orbiting wrap with a bottom surface of the orbiting wrap is provided to be communicated with the discharge hole, whereby a compressed refrigerant may be discharged through the auxiliary discharge path.

Abstract: A motor-driven Roots pump includes a housing, a drive shaft and a driven shaft that have axial lines parallel with each other, and a gear chamber. The housing includes a first partition that has a first defining surface, a second partition having a second defining surface, and a relief recess. An addendum circle of the drive gear and an addendum circle of the driven gear intersect with each other at a first intersection point. A plane that includes both the axial lines is defined as an imaginary plane. The first intersection point is located on a side of the imaginary plane on which the drive gear and the driven gear start meshing with each other. An opening of the relief recess is opposed to the first intersection point and is arranged in a region on a side of the imaginary plane on which the first intersection point is located.

Abstract: A cylindrical symmetric volumetric machine, includes a housing (2) with two co-operating rotors (6a, 6b) therein, namely an outer rotor (6a) mounted rotatably in the housing (2) and an inner rotor (6b) mounted rotatably in the outer rotor (6a), whereby a compression chamber (8) is located between the rotors (6a, 6b), which will move by rotation of the rotors (6a, 6b) from the inlet side (9a) of the rotors (6a, 6b) to the outlet side (9b) of the rotors (6a, 6b), wherein the inlet side (9a) of the outer rotor (6a) is provided with a ventilator (12), to supply air to the compression chamber (8).

Abstract: The disclosure discloses a method for determining reasonable design area of roots pump rotor profile of roots pump and its application, and belongs to the field of mechanical design. According to the method of the disclosure, after a relation between the roots pump rotor profile and performance parameters is established, constraint conditions for avoiding a closed volume and undercutting are further determined, so that a reasonable design region of a roots pump rotor blade peak curve is determined. Reference is given when the roots pump rotor profile is designed, i.e., the rotor profile with the blade peak curve being not within the reasonable design region inevitably causes the problem of closed volume or undercutting in application, so that the design of the rotor profile that causes the closed volume or undercutting can be avoided when the roots pump rotor profile is designed.

Abstract: A supercharger rotor comprising a plurality of lobes around a center axis, each lobe of the plurality of lobes comprising a rotor profile. The rotor profile comprises a tip, a convex addendum comprised of at least two interpolated and stitched spline curves, an undercut region, and a root base.

Abstract: A scroll compressor includes a fixed scroll, a movable scroll revolvable with respect to the fixed scroll, and a crankshaft rotatable to cause the movable scroll to revolve. A discharge port is formed in a first scroll of the fixed scroll or the movable scroll. A cutout portion is formed in a second scroll of the fixed scroll or the movable scroll. The cutout portion formed in the second scroll at least partially passes through a profile of the discharge port formed in the first scroll because of revolution of the movable scroll.

Abstract: A pumping unit is provided, including a primary vacuum pump of a multistage dry type, including at least four pumping stages fitted in series; and a two-stage Roots vacuum pump, including a first pumping stage and a second pumping stage fitted in series, the second pumping stage being fitted in series with and upstream of a first pumping stage of the primary vacuum pump in a direction of flow of gases to be pumped, in which a ratio of a volume displacement of the first pumping stage of the two-stage Roots vacuum pump to a volume displacement of the second pumping stage of the two-stage Roots vacuum pump is less than six, and in which a ratio of a volume displacement of the second pumping stage of the two-stage Roots vacuum pump to a volume displacement of the first pumping stage of the primary vacuum pump is less than six.

Abstract: A scroll compressor for a motor vehicle air-conditioning system includes a compressor housing, two interleaving spirals within the compressor housing, of which one spiral is stationary and the other spiral is movable eccentrically on a circular orbit, whereby the volume of compression chambers formed between the spirals changes cyclically and refrigerant is suctioned in and compressed; at least one refrigerant outlet port for ejecting the compressed refrigerant in a wall, frontal to the spirals, of the compressor housing in the center of the stationary spiral, wherein in the spiral end region on the inner end of at least one of the two spirals the concave side of the spiral wall is provided with a cut that has the form of a cone segment with concave curvature, decreasing from the upper end in the direction toward the lower end of the spiral wall.

Abstract: The invention relates to a rotary piston pump comprising a housing with a housing interior, an inlet opening, and an outlet opening; a first rotary piston which is mounted within the housing interior in a rotational manner about a first rotational axis; and a second rotary piston which is mounted within the housing interior in a rotational manner about a second rotational axis. The first rotary piston and the second rotary piston engage into each other in a region between the first and the second axis and displace liquid. The first rotary piston has a frame assembly which comprises multiple mutually spaced plates and is at least partly filled and enveloped with a polymer material.

Abstract: A scroll compressor is provided that may include an orbiting scroll having an orbiting wrap, and which performs an orbiting motion; and a fixed scroll having a fixed wrap to form a compression chamber including a suction chamber, an intermediate pressure chamber, and a discharge chamber, by being engaged with the orbiting wrap. A wrap thickness of the fixed wrap may be greater than a wrap thickness of the orbiting wrap within a range which forms the suction chamber. With such a configuration, even if the fixed scroll or the orbiting scroll is thermally-expanded, a transformation of the fixed wrap at a suction side may be prevented. This may prevent a gap between the fixed wrap and the orbiting wrap at an opposite side to the suction side, thereby enhancing compression efficiency.

Abstract: A bearing housing for an exhaust gas turbocharger may include a bearing housing cover arranged on a bearing housing wall. The bearing housing cover may include a penetrating rotation-symmetrical sealing recess with a centre axis and may have a locating surface facing the bearing housing wall and radially extending from the centre axis. The bearing housing may include a sealing bush arranged in at least one region of the sealing recess. The sealing bush may have a stop surface arranged opposite the locating surface and may include a penetrating shaft recess disposed rotation-symmetrical relative to the centre axis. The bearing housing cover may further include an at least partly circulating groove disposed on the locating surface radially spaced from the centre axis. The groove may include a drainage region arranged below the centre axis and extending from the centre axis radially to an outside.

Abstract: A cooling arrangement (1) for cooling of an apparatus (10) which in use may generate heat is disclosed. The cooling arrangement (1) comprises a first member (2), which comprises a first base (4) and a first spiral wrap (5) extending from the first base (4), and a second member (3), which comprises a second base (6) and a second spiral wrap (7) extending from the second base (6). The first spiral wrap (5) and the second spiral wrap (7) are interleaved. The first member (2) is configured to at least thermally couple the apparatus (10) thereto. At least one of the first member (2) and the second member (3) can be moved so as to result in an orbiting motion of one of the first spiral wrap (5) and the second spiral wrap (7) relatively to the other one of the first spiral wrap (5) and the second spiral wrap (7) such that a volume of fluid in at least one space between the first spiral wrap (5) and the second spiral wrap (7) progressively moves during the orbiting motion.

Abstract: The invention relates to a rotor pair for a compressor block of a screw machine, wherein a rotor pair comprises a secondary rotor that rotates about a first axis and a main rotor that rotates about a second axis, wherein the number of teeth of the main rotor is 3 and the number of teeth of the secondary rotor is 4. The relative profile depth of the secondary rotor is at least 0.5, preferably at least 0.515, and at most 0.65, preferably at most 0.595. rk1 is an addendum circle radius drawn around the outer circumference of the secondary rotor and rf1 is a dedendum circle radius starting at the profile base of the secondary rotor, wherein the ratio of the axis distance of the first axis from the second axis and the addendum circle radius rk1 is at least 1.636, and at most 1.8, preferably at most 1.733.

Abstract: Disclosed is a vane pump comprising a cam ring accommodated in a pump housing, a rotor accommodated rotatably with respect to a rotational shaft in the cam ring, and a plurality of vanes coupled to the rotor to discharge fluid, wherein the cam ring has a ring shaped inner profile varied between a maximum radius (Rmax) and a minimum radius (Rmin) in a circumferential direction with respect to the rotational shaft, and the ring shaped inner profile comprises: a cycloid curve passing through a maximum radius point; a circular arc passing through a minimum radius point; and a tangent line connecting the cycloid curve to the circular arc with a tangential curvature.

Abstract: Provided is an internal gear pump. The shape of any one of a plurality of external teeth and a plurality of internal teeth of the pump is formed on the basis of formulae (1)-(5). r=ro?dr·cos ?,??Formula (1): Px=(ro?dr)+1/4dr{1?cos(2?)},??Formula (2): Py=1/4dr{?2?+sin(2?)},??Formula (3): Qx=Px?r·cos ?,??Formula (4): Qy=Py+r·sin ???Formula (5):.

Abstract: In a scroll compressor, breakage of a spiral end portion of a spiral wall (10c, 11c) of a scrolls is prevented. [Solving means] In a scroll compressor including: a fixed scroll (10) including an end plate (10a) and a spiral wall (10c) extending upright from the end plate (10a); an orbiting scroll (11) including an end plate (11a) and a spiral wall (11c) extending upright from the end plate (11a); and a drive shaft (8) configured to transmit a rotational power to the orbiting scroll (11), and configured to compress a compressed fluid by an orbital motion of the orbiting scroll (11), an extending portion (113) which does not come into contact with the spiral wall (10c) of the fixed scroll (10) is provided so as to extend from a spiral end portion (112), which corresponds to a terminal end of a wall surface (compression forming portion (111)) which forms a compression chamber (15) on a spiral wall (11c) of the orbiting scroll (11).

Abstract: A claw pump includes: a housing; two rotating shafts which are disposed parallel; a pair of rotors respectively fixed to the two rotating shafts; a rotary drive device driving the pair of rotors; and a suction port and discharge ports formed in a partition wall of the housing. The discharge ports are constituted by a first discharge port and a second discharge port. The first discharge port is formed at a position that communicates with an initial stage compression space formed at an initial stage of a compression stroke in a compression space that is formed by joining a first pocket and a second pocket. The claw pump includes an opening/closing mechanism which opens the first discharge port when a pressure of the initial stage compression space reaches a threshold and closes the first discharge port when the pressure does not reach the threshold.

Abstract: A vane pump (1) is disclosed comprising a housing (2) having a stator bore, a rotor (4) being rotatably mounted within said stator bore, and having a number of vanes (5) slidably mounted in said rotor (4) in radial direction of said rotor (4), an inlet (11) and an outlet (12). Such a vane pump should have a good efficiency. To this end said inlet (11) opens in an axial end wall of said stator bore (3) and said outlet (12) is connected to an outflow area formed in a circumferential wall (3) of said stator bore.

Abstract: A scroll compressor that includes a housing and scroll compressor bodies disposed in the housing. The scroll bodies include a non-orbiting scroll body (also referred to as “fixed”) and a moveable body, where scroll bodies have respective bases and respective scroll ribs that project from the respective bases. The scroll ribs are configured to mutually engage, and the movable scroll body orbits relative to the fixed scroll body for compressing fluid. A pilot ring engages a perimeter surface of the fixed scroll body to limit movement of the fixed scroll body in the radial direction. A simplified holding plate prevents rotation between the pilot ring and the fixed scroll body.

Abstract: A negative pressure pump includes an electrically insulative casing an electrically conductive rotary shaft and an electrically conductive vane. The casing is formed in a tubular shape, an axial direction one end of which is closed off by a cap body. The rotary shaft is disposed in the casing, is mechanically and electrically connected to an earthed power source, and is rotated by power being transmitted from the power source. The vane is disposed in the casing, is supported at the rotary shaft to freely reciprocate in a direction orthogonal to the rotary shaft, and is electrically connected to the power source via the rotary shaft. The vane rotates integrally with the rotary shaft, and end portions of the vane slide over an inner wall face of the casing. The vane divides the interior of the casing into a plurality of spaces and generates negative pressure.

Abstract: A vane pump with a pump housing in which a cam ring is constructed or arranged, and wherein a rotor is provided that is mounted in the cam ring so that it can rotate about a rotational axis , wherein the cam ring has an inner contour with a variable radius that varies between a maximum radius and a minimum radius in the circumferential direction about the rotational axis , wherein, in the radial gap between the inner contour and the rotor , a number of lift sections is constructed with pump chambers constructed in these sections, and wherein vane elements are mounted on the rotor , wherein these elements slide against the inner contour of the cam ring and limit the pump chambers in the circumferential direction. According to the invention, the radius of the inner contour varies about the rotational axis according to the function: r=r0+a·sin(n·?), where r0=(rmax+rmin)/2, a =(rmax?rmin)/2, and ?=phase angle of the radius (r) between (rmin) and (rmax) in the direction of rotation of the rotor .

Abstract: The invention relates to a rotary piston engine (2) which operates as a pump, condenser or motor for a liquid or gaseous medium. The rotary piston engine (2) has a first gear (4) having a first central axis (I), a second gear (6) arranged opposite the first gear (4) and having a second central axis (II), and a drive shaft (8) having a third central axis (III) and a sliding plane (10, 12) fixedly connected to the drive shaft (8). The first central axis (I) and the second central axis (II) enclose an angle (?3) which is not equal to 180°. The third central axis (III) and at least one central axis (I, II) from the group comprising the first central axis (I) and second central axis (II) enclose an angle (?1, ?2) which is not equal to 0° or 90°. The sliding plane (10, 12) and the central axis (I, II) are perpendicular to each other.

Abstract: Provided is an oil pump rotor capable of improving a volume efficiency and a quietness. When a diameter of a base circle bi of an inner rotor is ? bi; a diameter of a first outer rolling circle Di is ? Di; a diameter of a first inner rolling circle di is ? di; a diameter of a base circle bo of an outer rotor is ? bo; a diameter of a second outer rolling circle Do is ? Do; a diameter of a second inner rolling circle do is ? do; and an eccentricity amount between the inner rotor and the outer rotor is e, ? bi=n·(? Di+? di) and ? bo=(n+1)·(? Do+? do) hold; either ? Di+? di=2e or ? Do+? do=2e holds; and ? Do>? Di and ? di>? do hold. When a clearance between the inner rotor and the outer rotor is t, 0.3?((? Do+? do)?(? Di+? di))·(n+1)/t?0.6 holds, provided that ? Di+? di=2e; or 0.3?((? Do+? do)?(? Di+? di))·n/t?0.6 holds, provided that ? Do+? do=2e.

Abstract: A negative pressure pump has: a housing; a rotating shaft having a shaft portion, and a supporting portion; a vane that is supported at the supporting portion so as to freely move reciprocally in a direction orthogonal to the rotating shaft, and that rotates integrally with the rotating shaft, and whose end portions slide on an inner wall surface, and that sections an interior of the housing into plural spaces; an intake portion that is formed in the housing; a discharging portion that is formed further toward a vane rotating direction downstream side than the intake portion; and a concave portion that is formed in a bottom surface between the discharging portion and a curved surface in a vane rotating direction, and that communicates with a circular hole, and guides the lubricant, that is moved by the vane, to the circular hole.

Abstract: An internal gear pump includes a pump rotor (4) in which a meshing point between an inner rotor (2) having n teeth and an outer rotor (3) having (n+1) teeth is located rearward, in a rotational direction of the rotor, relative to an eccentric axis (CL) along which a center (OI) of the inner rotor and a center (OO) of the outer rotor are disposed. A tooth-surface curve of the outer rotor (3) near a meshing section thereof is formed by duplicating thereto a tooth-surface shape of the inner rotor (2) near a meshing section thereof.

Abstract: A scroll type fluid machine for improving compression efficiency while preventing contact between wrap sections of opposed scrolls, includes a first scroll member provided with a wrap section of a spiral shape on an end plate, a second scroll member disposed at a position opposed to the first scroll member and provided with a wrap section of a spiral shape on an end plate, cooling fins arranged on a back side surface of the end plate of at least one of the first scroll member and the second scroll member, and projected sections arranged on the wrap section of at least one of the first scroll member and the second scroll member, in which a difference of thicknesses in the radial direction of the wrap section at a distal end and a base end of the projected sections is changed depending on a position in a peripheral direction.

Abstract: An internal gear pump in which an inner rotor and an outer rotor are arranged in a rotor housing chamber. A deepest meshing section is located in the vicinity on a line connecting a center of the inner rotor and a center of the outer rotor. A center of the rotor housing chamber is offset, from a position in which the center and the center of the outer rotor coincide with each other, to the deepest meshing section side by an amount smaller than a tip clearance, which is a gap between the tooth tip of the inner rotor and the tooth tip of the outer rotor in the vicinity of a seal land between a terminal end side of an intake port and a start end side of a discharge port.

Abstract: Systems and methods for determining a flow rate or volume of fluid. The system includes a positive displacement meter including a plurality of non-contact sensors and gears configured to rotate in response to fluid flow through the meter. The gears may include detectable areas that may be sensed by the plurality of non-contact sensors to determine a rotational direction of the gears. The plurality of non-contact sensors may also be configured to generate respective detection signals indicative of a rotation state of the gears. The controller may be configured to receive the detection signals, determine a current rotation state, and increment a rotational count based on the changes in the current rotation state. The controller may use the rotational count to determine a flow rate or volume of fluid.

Abstract: A tooth profile of an inner rotor 2 is formed by an envelope of a group of circular arcs of a locus circle C having a center on a trochoidal curve TC. The envelope of the group of circular arcs is formed by rolling a rolling circle having a predetermined diameter along a base circle without slipping and drawing the trochoidal curve TC based on a point distant from the center of the rolling circle by a distance equivalent to an amount of eccentricity between the two rotors. A diameter d2 of the locus circle C is constant until one point between an addendum point and a dedendum point of the inner rotor and changes from the one point such that a diameter d2B at the dedendum point becomes larger than a diameter d2T at the addendum point of the inner rotor.

Abstract: In an internal gear pump 9, a diameter of a base circle is set to A mm, a radius of a rolling circle is set to b mm, a diameter of a locus circle is set to C mm, and an amount of eccentricity is set to e mm. A trochoidal curve T is drawn by rolling the rolling circle along the base circle without slipping and by using a locus of a fixed point distant from a center of the rolling circle by e. A tooth profile of an inner rotor 2 having n teeth is formed based on an envelope of a group of the locus circles each having a center on the trochoidal curve T. A pump rotor 1 is formed by combining the inner rotor with an outer rotor having (n+1) teeth. A tooth-profile curve of the inner rotor satisfies the following expression (1). Because K<1 is satisfied, cusps s are not formed at opposite edges of each addendum of the inner rotor 2.

Abstract: A water meter of the present invention may accurately measure a flow rate and reduce power consumption. The water meter includes a body including an inlet unit and an outlet unit, an impeller unit provided to rotate due to a fluid flowing in the body, a cover member that covers one side of the impeller unit and includes a guide groove formed therein, and sensors that are provided on one side and the other side of the cover member and are spaced apart from each other to face each other. The impeller unit includes blades interfering with the fluid, a shaft forming a rotational center of the blades, and a cut-off unit that extends from one side of the plurality of blades to be inserted into the guide groove, and selectively cuts off signal transmission between the plurality of sensors.

Abstract: An internal gear pump includes an inner rotor having n teeth and an outer rotor having (n+1) teeth. A tooth profile of the inner rotor is an envelope of a group of locus circles (13) each having a diameter C and having a center on a trochoidal curve (T), the trochoidal curve being drawn along a locus of a fixation point, which is located distant from a center of a rolling circle (12) by e, when the rolling circle (12) rolls along a base circle (11) without sliding. A tooth profile of the outer rotor is an envelope of a group of tooth-profile curves of a formation inner rotor, the envelope being obtained by first drawing the formation inner rotor in which a diameter of the locus circle (13) is equal to C? determined from expression (C?t), revolving a center (OI) of the formation inner rotor by one lap along a circle (S) having a diameter (2e) and centered on a center (OO) of the outer rotor, and rotating the formation inner rotor 1/n times during the revolution.

Abstract: A blade-type fluid transmission device includes a rotor eccentrically located in the room of a stator and the outer periphery of the rotor is tangent to the inner periphery of the room. At least one blade is pivotably connected to stator and movably inserted in at least one slot of the rotor. The distal end of the at least one blade is in contact with the inner periphery of the room so as to form a space for receiving fluid between the outer periphery of the rotor and the inner periphery of the room. The contact between the at least one blade and the inner periphery of the room increases the efficiency for transmitting fluid which enters into the stator from an inlet and leaves from the stator from an outlet.

Abstract: A vane pump with a pump housing in which a cam ring is constructed or arranged, and wherein a rotor is provided that is mounted in the cam ring so that it can rotate about a rotational axis , wherein the cam ring has an inner contour with a variable radius that varies between a maximum radius and a minimum radius in the circumferential direction about the rotational axis , wherein, in the radial gap between the inner contour and the rotor , a number of lift sections is constructed with pump chambers constructed in these sections, and wherein vane elements are mounted on the rotor , wherein these elements slide against the inner contour of the cam ring and limit the pump chambers in the circumferential direction. According to the invention, the radius of the inner contour varies about the rotational axis according to the function: r=r0+a·sin(n·?), where r0=(rmax+rmin)/2, a =(rmax?rmin)/2, and ?=phase angle of the radius (r) between (rmin) and (rmax) in the direction of rotation of the rotor .

Abstract: A rotary compressor, used e.g. in an air conditioner, includes a compressing unit having an end plate that closes an end portion of an annular cylinder. The end plate includes a groove portion accommodating a discharge valve portion having a reed valve type discharge valve and a discharge-valve limiter. The discharge valve portion is attached to the groove portion with a rivet. The groove portion has a rivet-side enlarged diameter portion formed into a semicircular step shape, and a diameter of the rivet-side enlarged diameter portion other than a bottom side thereof is larger than a diameter of the bottom side. This prevents a punch P that swages the rivet from interfering with the groove portion when attaching the discharge valve portion to the groove portion with the rivet.

Abstract: A metering pump with a special-shaped cavity comprising a housing, a rotor and two cover plates. The housing is a cylinder with a special-shaped surface inner cavity formed by combining two circular arc surfaces with two non-circular arc surfaces and a planar surface, an inlet and an outlet. The rotor comprises a rotor body and two pairs of combined sliding plates. The housing is matched with the cover plates for constituting a sealed cavity. When the rotor rotates, the non-circular arc surface of the special-shaped surface inner cavity can enable the two pairs of the combined sliding plates to slide in a cross manner so as to suck in fluid from the inlet and press out the fluid from the outlet. When the rotor rotates one cycle, four standard volumes are formed in a cavity body and the equal quantity of the fluid flows by the cavity body.

Abstract: An object is to meet the demands for increasing the number of teeth of a rotor in an internal gear pump while maintaining a theoretical discharge amount by using an equivalent body configuration so as to enhance the pump performance relating to discharge pulsation due to the increased number of teeth. In a pump rotor 1 formed by combining of an inner rotor (2) having N teeth and an outer rotor (3) having (N+1) teeth and disposing the rotors eccentrically relative to each other, the relational expression ?Dmax<1.7e·sin(?/180)/sin {?/(180·N)} is satisfied, ?Dmax being a maximum value of a working pitch diameter of the inner rotor (2) and the outer rotor (3), and a working position (G) of the inner rotor (2) and the outer rotor (3) is always located rearward of an eccentric axis (CL) in a rotating direction of the rotor.

Abstract: An oil pump is increased to inhibit noise generation and durability is also improved. The oil pump includes a pump body, an inner rotor having outer teeth, and an outer rotor having inner teeth. A maximum partition portion is formed between a trailing end side of an intake port and a leading end side of a discharge port in a rotor chamber of the pump body. Among cells constituted by the outer teeth of the inner rotor and the inner teeth of the outer rotor, a central cell positioned in the location of the maximum partition portion and adjacent cells positioned before and after the central cell in the direction of rotation are sealed by mutual contact of the outer teeth and the inner teeth. The outer teeth and the inner teeth constituting cells other than the central cell and adjacent cells are not in contact with each other.

Abstract: The rotary diaphragm pump has a flexible, resilient diaphragm band surrounding an elliptical frame within a case having four chambers surrounding an elliptical core. An articulating mechanism has a plurality of wheels traveling along the elliptical edges of the frame. The mechanism extends and retracts as the wheels move from maximum extension along the major axis of their elliptical tracks to minimum extension at the minor axis of their tracks. This mechanism drives a pair of actuator rollers along the inner surface of the diaphragm, periodically forcing the diaphragm into the surrounding chambers to produce the pumping action. Each chamber has an inlet port and an outlet port. The various ports may be interconnected to provide one or more multi-stage pumps in combination with one or more single-stage pumps, as desired. Two or more pumps may be joined in tandem to provide greater capacity from a single drive shaft.

Abstract: The present invention deals with the analytical definition of a tooth profile for rotors used in gear pumps. The purpose is to obtain a pump characterized by noiseless operation, minimization of vibrations and pressure overoscillations generated in operating conditions at the beginning and end of life, and high specific displacement, in such a way to increase the delivery of the pump in given volume conditions. This profile is characterized by an active profile of the tooth flanks with involute stub-tooth with transverse contact ratio (?t) comprised in the range from 0.4 to 0.45, helical teeth with helical contact ratio (??) comprised in the range from 0.6 to 0.85, circular inactive tooth bottom and top profiles, with center (Of, Ot) and radius (rf, rt) defined by a non-dimensional parameter ? in the range from 1.1 to 1.6.

Abstract: A roots type fluid machine includes suction and discharge ports, rotary shafts and a pair of rotors. The rotor has a number n of lobe and valley portions with apex and bottom ends. The lobe portions are located on imaginary lines extending radially from an axis of the rotary shaft. The outer surface of each one of the rotors is generated by rotating an outline of the rotor including an arc and involute and envelope curves around and moving the outline in the direction of the axis. The arc has a radius R and a center located on the imaginary line. The involute curve is formed by an imaginary base circle having a radius r and a center located on the axis. The envelope curve is formed by an arc having a radius R. The number n is four or more. A torsional angle ? is over 360/n degrees.

Abstract: A rotary compressor includes: a driving element which is provided inside a sealed container; and a rotary compression element which is provided inside the sealed container so as to be located below the driving element. A refrigerant discharge pipe is inserted from a side surface of the sealed container above the driving element into the sealed container, and is opened in the horizontal direction. A refrigerant compressed by the rotary compression element is discharged from a discharge hole into the sealed container, and is discharged from the refrigerant discharge pipe to the outside of the sealed container. The position of the discharge hole is set to a position below an area A1 on the opposite side of the opening direction of the refrigerant discharge pipe from a line L1 passing an opening surface of the refrigerant discharge pipe and perpendicular to the opening direction of the refrigerant discharge pipe.

Abstract: A rotary motor for compressible media, containing at least one impellor and at least one stator mounted between two mutually coupled and concurrently mounted bearing plates, adjusted for a mounting of double sided led out driving shaft of the impellor on which is mounted a rotary piston mounted in a chamber of the stator equipped with sealing lids, wherein the rotary piston with elliptical crosscut is mounted into symmetrically shaped triangular chamber equipped with rounded peaks, when each of them is equipped with at least one port for an entry and an exit of the compressible media, in way that a lengthwise axis (op) of the rotary piston which is identical to the driving shaft axis is due to reach of simultaneous circular movement of the stator in contra direction to the rotary piston rotating namely at parallel advance of all points of the stator along the circle with eccentricity radius (e) and is moved with regard to a lengthwise axis (os) of the chamber of the stator of the value of an eccentricity (e),

Abstract: A rotary chambered fluid energy-transfer device includes a housing with a central portion having a bore formed therein and an end plate forming an arcuate inlet passage, with a radial height and a circumferential extent. The device also includes an outer rotor rotatable in the central portion bore with a female gear profile formed in a radial portion defining a plurality of roots and an inner rotor with a male gear profile defining a plurality of lobes in operative engagement with the outer rotor. A minimum radial distance between an outer rotor root and a corresponding inner rotor lobe define a duct end face proximate the end plate, wherein the duct end face has a radial height substantially equivalent to the inlet passage radial height at a leading edge of the inlet passage.

Abstract: In an internal gear pump 9, a diameter of a base circle is set to A mm, a radius of a rolling circle is set to b mm, a diameter of a locus circle is set to C mm, and an amount of eccentricity is set to e mm. A trochoidal curve T is drawn by rolling the rolling circle along the base circle without slipping and by using a locus of a fixed point distant from a center of the rolling circle by e. A tooth profile of an inner rotor 2 having n teeth is formed based on an envelope of a group of the locus circles each having a center on the trochoidal curve T. A pump rotor 1 is formed by combining the inner rotor with an outer rotor having (n+1) teeth. A tooth-profile curve of the inner rotor satisfies the following expression (1). Because K<1 is satisfied, cusps s are not formed at opposite edges of each addendum of the inner rotor 2.