Abstract: A rotatable sound attenuation device is provided comprising a central portion rotatable about a first axis, a radial portion extending outwardly from the central portion and a chamber having a closed first end and a second end opening radially outwardly of the radial portion and defining a second axis therein having a radial component thereto. A piston is disposed within the chamber and is moveable to a location along the second axis in response to a centrifugal force imparted on the piston by rotation of the central portion and the radial portion about the first axis. A biasing member operates to limit movement of the piston along the second axis. A quarter wave chamber is defined by the second, open end of the chamber and the piston and has a sound attenuating length defined by the location of the piston along the second axis of the chamber.

Abstract: A complex dry vacuum pump including a root rotor and a screw rotor is disclosed for manufacturing semiconductors and/or displays in a vacuum state in a process chamber, and discharging gaseous material and/or by-products generated during manufacturing to the exterior of the process chamber. The pump can provide high gas compression transfer efficiency so as to form a vacuum in the process chamber and/or keep high gas compression transfer efficiency when the gaseous material and/or by-products are discharged. Balance between the root rotor and the screw rotor can prevent vibration and noise generated in the vacuum pump, and molding material associated with the pump may allow a stator coil to be separated and prevent various by-products from flowing from the vacuum pump.

Abstract: The present invention provides methods for designing single-lobe or double-lobe rotors which enable a defined rotor and a conjugate rotor intermeshing and conjugating to each other and by parameterized sets to generate curve portions of half two lobes of the defined rotor including a curve E, an arc A, an arc B, an arc F, an arc C, an arc G and a horizontal line Y. The main feature is that a radius of the arc C being defined by following equation: r C = x + r F = ? x ? ? sin ? ? ? + D 2 ? ? x = ( D / 2 ) - r F 1 - sin ? ? ? ; ? r C = ( D / 2 ) - r F 1 - sin ? ? ? + r F in which rF is two times pitch circle radius(Rp) of the defined rotor deducting the maximum radius(R) of the defined rotor(rF=2 Rp?R), and a center of the arc C is located in a straight extension direction from a center of the defined rotor and an end point of an arc F.

Abstract: A rotary blower with an isothermal air jacket having multiple interconnected and synchronized parallel multi-lobe rotors with the same number of lobes for propelling flow from a suction port to a discharge port of an inner casing without internal compression. The isothermal air jacket is shaped to surround the blower outer body, but is oversized to provide adequate flow spaces with outer skin of the blower to enable an effective cooling of the outlet casing and an effective heating of the inlet casing so that the whole casing temperature will tend to be more uniform and isothermal, resulting in a blower with less vibration, lower noise and longer blower life.

Abstract: The present invention provides a method for designing lobe-type rotors which enables a defined rotor and a conjugate rotor with three or more than three lobes intermeshing and conjugating to each other; by setting suitable parameters to generate a curve portion of a single lobe of the defined rotor as a pattern including a curve E, an arc A, an arc B, a straight line Y, an arc C and an arc F, then imaging (N-1) copy of the curve portion in which N represents number of lobes and is bigger than or equal to three, and then respectively rotating each curve portion in sequence from an appropriate degree computed by 360/N to a terminal degree computed by (N-1)*360/N; whereby to integrately form the defined rotor with three or more than three lobes.

Abstract: The present invention provides a method for designing lobe-type rotors which enables a defined rotor and a conjugate rotor having three or more than three lobes intermeshing and conjugating to each other and by setting suitable parameters to generate curve portions of a single lobe of the defined rotor as a pattern including a curve E, an arc A, an arc B, an arc F, and a straight line Y; the main feature of the present invention is that a radius rB of the arc B is defined by following equation: r B + ( R - r B ) ? sin ? ? ? = D 2 r B = D / 2 - R ? ? sin ? ? ? 1 - sin ? ? ? moreover, the straight line Y is the external common tangent line of the arc B and the arc F, and respectively getting two tangent points therefrom to be defined as two end points of the straight line Y.

Abstract: The present invention provides a method for designing single-lobe rotors of the present invention includes: curve portions of the of a curve E, an arc A, an arc B, an arc F, an arc C, an arc H, a straight line Y, and an arc G, wherein a center of the arc H located in line with a center of the arc C through a center of the defined rotor, and a center of the arc G is same as the center of the defined rotor wherein a radius of the arc G is defined between a center of the arc G and an end point of the arc H, from which two end points of the arc G is smoothly connected with the arc H and the arc C. The single-lobe rotors generated by the method is able to provide higher compression ratio and larger discharge capacity, secure a smooth process while working chamber undergoing compression and expansion, and reduce leakage.

Abstract: A method of designing rotors for a Roots blower comprising a housing having cylindrical chambers, the housing defining an outlet port (19). The blower includes meshed, lobed rotors (37,39) disposed in the chambers, each rotor including a plurality N of lobes (47,49), each lobe having first (47a,49a) and second (47b,49b) axially facing end surfaces. Each lobe has its axially facing surfaces defining a twist angle (TA), and each lobe defines a helix angle (HA). The method of designing the rotor comprises determining a maximum ideal twist angle (TAM) for the lobe as a function of the number N of lobes on the rotor, and then determining a helix angle (HA) for each lobe as a function of the maximum ideal twist angle (TAM) and an axial length (L) between the end surfaces of the lobe. A rotor designed in accordance with this method is also provided.

Abstract: A Roots-type blower with helical cycloidal rotors features relief recesses in the chamber walls, isolated from the input and output ports. The relief recesses counter variation in leakback flow with angular position intrinsic to helical cycloidal rotors, attenuating a noise source.

Abstract: The invention relates to a rotary piston pump comprising a medium inlet, a medium outlet, and two rotary pistons. Each rotary piston has an outer contour with a constant radius R around the axis thereof, in two opposing peripheral regions, respectively over a peripheral angular region ?, and, in the other peripheral regions, respectively a continuous contour with radii which are measured from the axis and are shorter than the radius R. The rotary pistons are helicoidal, respectively one front side of each rotary piston being rotated in relation to the other front side by a rotary angle ?. The medium inlet and the medium outlet have a rectangular cross-section with two axially parallel edges and two edges extending at right angles to said parallel edges.

Abstract: A gear assembly for transmitting torque from one shaft to another comprises two intermeshing gears mounted on respective shafts. One of the gears comprises a hub member for receiving one of the shafts, a toothed annular member mounted for rotation with the hub member. At least one spring provided between the hub member and the annular member has stiffness capable of reducing torsional vibrations and noise induced during rotation of the gears by the eccentricity of at least one of the gears.

Abstract: A gear pump applicable for feeding a high-pressure and high-viscosity fluid, such as a molten resin is provided. In the gear pump 100, the fluid is fed from a suction port side to a discharge port side by the rotation of gears. The gears are formed in a pair and meshing with each other. The gears are double-helical gears having a one-point continuous contact tooth profile. For the gears, the ratio D/B of the outer diameter D and the tooth width B are set to 1.1 to 1.15. When the ratio D/B is equal to or smaller than 1.1, a bearing may be damaged due to an excessively increased bearing load. On the other hand, when the ratio D/B is larger than 1.15, in accordance with an increase in the overall size of the pump external dimension, the mechanical efficiency is lowered, and the overall efficiency is also lowered.

Abstract: The invention reduces power consumption and makes a rotor with ease. As illustrated in FIG. 2, a multistage roots pump (1) in the invention includes upstream rotors (R1a, R1b, R2a, R2b) having multiple teeth, supported by a pair of revolving shafts (A1, A2); and downstream rotors (R3a, R3b-R5a, R5b) having an identical number of teeth (31) with the upstream rotors, supported by revolving shafts (A1, A2). The discharge area formed by the outer periphery of the downstream rotors (R3a, R3b-R5a, R5b) and the inner periphewy of the pump chambers (P1-P5) is smaller than that of the upstream rotors (R1a, R1b, R2a, R2b).

Abstract: A pump comprises a driving rotor and a driven rotor that are positioned in a housing such that, as the driving rotor and the driven rotor rotate, the teeth of the driving rotor and the teeth of the driven rotor mesh to form a positive displacement seal. The teeth of the driving rotor and the driven rotor are configured such that seals between the inlet side and the discharge side of the pump are formed between only the leading surfaces of the teeth of the driving rotor and the trailing surfaces of the teeth of the driven rotor.

Abstract: Methods, devices, and systems are disclosed for combining fluids of different pressures and flow rates in, for example, gas gathering systems, gas wells, and other areas in which independently powered compressors are not desired. Methods, devices, and systems for turning a shaft are also provided, as are methods, devices, and systems for dropping pressure in a gas line.

Abstract: Disclosed is a system for pumping of fluid by a single pump from a plurality of storage tanks in situations where some of the tanks should be pumped simultaneously at predefined, equal or unequal flow rates, and where some of the tanks should be pumped sequentially, in an orderly manner. The system needs no restrictors or valves to determine the flow rate or the sequence of pumping. In some embodiments, the rate of flow out of the pump does not change when one tank becomes empty before another.

Abstract: A roots type fluid machine includes a housing, a pair of parallel rotary shafts and two-lobe rotors. Each rotor includes two lobe portions and two well portions. Each lobe portion has a profile of convex arc with a radius R and each well portion has a profile of concave arc which is an envelope of the convex arc of the lobe portion. The rotor has a configuration defined by a curve which includes the convex arc, the concave arc and further an involute curve with a base radius r between the convex and concave arcs. The base radius r is set in a range L/(2?{square root over ( )}2)<r<0.3(?{square root over ( )}2)L where distance between axes of the rotary shafts is L, and the radius R is set in a range {(?{square root over ( )}2)/16}?L<R<{(27?5?{square root over ( )}2)/56}L.

Abstract: A roller cell pump having a shaped sliding surface composed of elliptical portions results from two different equations. The function of the unit is improved because the equations are modified and include adaptable parameters, so that by adaptation of the parameters, the shaped sliding surface can be adapted in portions optimally to the requisite function in that particular region of the shaped sliding surface, for instance the function of generating an underpressure or an overpressure. The course of the radii of the elliptical portions corresponds, at least in portions, to one of two equations that differ from the prior art.

Abstract: A double-lobe type rotor design process includes a process for forming a defined rotor and a process for forming a conjugate rotor, wherein the defined rotor and the conjugate rotor intermesh and conjugate to each other. The rotor profile curves suitably for the completed operation period of carryover, suction and exhaust could be well defined by proper parameters, thereby optimizing rotor performance, enhancing compression ratio, providing a smooth suction and exhaust process and avoiding noise and vibration.

Abstract: A helical screw rotor compressor is provided which includes a rotor housing that includes a barrel wall between two parallel end walls, an inlet port at a first end and an outlet port at a second end. The compressor has an internal shape corresponding to two parallel and mutually intersecting cylinders. The compressor includes two rotors which each include a shaft and a rotor body surrounding the shaft. The rotor bodies have parallel end surfaces adjacent to the end walls of the rotor housing, and each include helical lobes that have a crown, a first or leading flank surface on a first side of the crown and a second or trailing flank surface on a second side of the crown. The second or trailing flank surfaces of the lobes have a beveled or chamfered region adjacent to the end surface of the rotor body near the outlet port.

Abstract: A pump comprises a driving rotor and a driven rotor that are positioned in a housing such that, as the driving rotor and the driven rotor rotate, the teeth of the driving rotor and the teeth of the driven rotor mesh to form a positive displacement seal. The teeth of the driving rotor and the driven rotor are configured such that seals between the inlet side and the discharge side of the pump are formed between only the leading surfaces of the teeth of the driving rotor and the trailing surfaces of the teeth of the driven rotor.

Abstract: An engine including a housing formed with a pair of side-by-side intersecting substantially cylindrical cavities, and a pair of counter-rotating power rotors rotatably mounted within the cavities. The pair of power rotors include intermeshing lobes that each define open ended combustion chambers.

Abstract: A conjugate pair of intermeshing rotors having helical lobes having helical crests and intervening grooves and adapted for rotation about parallel axes within a working space of a screw rotor machine. Each rotor has a tip circle, a pitch circle, and a root circle, one rotor of each pair being a female rotor such that the major portion of each lobe of said female rotor is located inside the pitch circle of the female rotor. The other rotor is a male rotor formed such that the major portion of each lobe of said male rotor is located outside said pitch circle of the male rotor. The lobes of one rotor follow the grooves of the other rotor to form a continuous sealing line between said pair of rotors, each of the lobes having a primary and secondary flank portion, wherein the primary flank portion of said lobes of the female rotor have a profile formed from at least one ellipse and the primary flank portion of the lobes of the male rotor have a profile formed from at least one ellipses.

Abstract: The present invention provides an improved rotor mechanism to improve the mechanism of the intermeshing displacement rotor and valve rotor. The main feature is that the displacement rotor and the valve rotor provide the operation curve from the carryover period to intake period, which includes a pair of convex curves with different radius merging smoothly with each other, thereby providing a smooth transference of the intake, exhaust, and carryover, etc. and avoiding noise and vibration during the working process. Moreover, the displacement rotor and the valve rotor provide the operation curve from the starting of exhaust to the period of ending, which is defined by an arcuated surface thereby providing a rotor mechanism with great diplacement transference and high compression ratio.

Abstract: A rotary positive-displacement pump comprises two gear wheels which mesh with each other without encapsulation. Each gear wheel has a plurality of teeth with a profile which falls within a band of tolerance of ±{fraction (1/20)}th of the depth of the tooth with respect to a theoretical profile similar to a profile defined by a natural spline function passing through a plurality of nodal points having pre-established coordinates {X, Y}.

Abstract: A kind of gear is provided with shorter teeth, transition teeth and at least one longer tooth. The cross-section of the longer tooth is of a hawk beak shape, and the profile of the longer tooth is smoothly connected in series by a convex section, a tip section, a concave section, and a leading section The two sides of the longer tooth are each provided with a transition tooth which neighbors a shorter tooth on the opposite side of the longer tooth. The pair of engaging gears according to this invention have advantages of reducing the fluid leakage, canceling the inertia of the rotors, and minimizing the vibration and noise. This invention also discloses a fluid machine for conveying, compressing or expanding liquid or gaseous fluids, which includes a casing comprising a housing, an upper end cover and a lower end cover. At least one pair of engaging gears which includes one driving rotor according to this invention and one driven rotor according to this invention is accommodated in the housing.

Abstract: A rotary positive-displacement pump comprises two gear wheels which mesh with each other without encapsulation. Each gear wheel has a plurality of teeth with a profile which falls within a band of tolerance of ±{fraction (1/20)}th of the depth of the tooth with respect to a theoretical profile similar to a profile defined by a natural spline function passing through a plurality of nodal points having pre-established coordinates {X, Y}.

Abstract: A spherical gear pump that comprises two rotors, or geared spheres, with the teeth arranged around them in a circular band at right angles to their axis of rotation: the pump spheres are covered by close-fitting spherical cases or housings except at the central or most internal part of the connection between the gears on the two spheres, the fluid contained in the cavity created between the most external gears and the case or housing is moved during rotation from the intake to the outlet, one sphere is driven by its shaft and the other is dragged by the gearing between the two.

Abstract: This invention is directed to a novel wave tooth gear having a non-circular pitch curve and uniform wave teeth to create a tighter seal between meshing gears. The non-circular wave tooth gear has a major axis and a minor axis disposed perpendicular to the major axis, wherein the major axis is longer than the minor axis and includes a central hub, a plurality of teeth radially extending from the hub at locations surrounding the hub and a plurality of roots, each root positioned between adjacent teeth at locations surrounding the gear. The teeth include a head portion shaped as an arc segment of a first radius and the roots include a recess shaped as an arc segment of a second radius. The teeth heads are joined to adjacent roots by lines of tangency.

Abstract: At least two rotors are mounted in a chamber and rotate synchronously to compress and/or transport fluid. The chamber has the shape of partially overlapping circles with each circle intersecting the center of the adjacent circle. The rotors are non-eccentric and have curved sides with the same radius as the circles. In exemplary embodiments, the rotors are trochoidal and the chamber is epitrochoidal. Also provided are compressors, pumps, actuators, and engines incorporating the rotary machine.

Abstract: This invention is directed to a novel wave tooth gear having a non-circular pitch curve and uniform wave teeth to create a tighter seal between meshing gears. The non-circular wave tooth gear has a major axis and a minor axis disposed perpendicular to the major axis, wherein the major axis is longer than the minor axis and includes a central hub, a plurality of teeth radially extending from the hub at locations surrounding the hub and a plurality of roots, each root positioned between adjacent teeth at locations surrounding the gear. The teeth include a head portion shaped as an arc segment of a first radius and the roots include a recess shaped as an arc segment of a second radius. The teeth heads are joined to adjacent roots by lines of tangency.

Abstract: An engine displacement device including a casing with two internal overlapping rotor chambers, and rotors within the rotor chambers which are arranged to contra rotate to provide internal combustion and/or compression chambers. The casing provides for primary and secondary combustion of a fuel mix, where the device is adapted as a combustion engine.

Abstract: A pump for moving a fluid has a housing with an internal chamber accommodating a pair of rotors mounted on parallel shafts connected with gears operable to rotate the shafts in opposite directions. Each rotor has opposite end walls and protrusions and pockets that register in non-contacting relation during rotation of the rotors. Thrust bearings cooperating with the gears, shaft, and housing maintain the end walls of the rotors in spaced relation relative to the adjacent walls of the housing.

Abstract: A flow regulator is provided in a liquid delivery line. The flow regulator includes flow regulation a body having an inflow port through which liquids different from each other in a property such as density, viscosity, etc flow in the body, and an outflow port through which the liquids flow out from the body. A set of rotators, which are rotated within the body in respective directions opposite to each other is provided to move the liquid by given volumes along the internal wall of the body. And a drive unit for driving the set of rotators is also provided. This construction provides an apparatus which can be used for delivering a liquid, which, in delivering liquids different from each other in viscosity, a given volume of the liquid can be accurately delivered to a liquid delivery line in a continuous manner even though the viscosity of the liquids have varied.

Abstract: A pump for moving a fluid has a housing with a internal chamber accommodating a pair of rotating pistons. Each piston has protrusions that register with pockets in the other piston in non-contact relation as the pistons rotate.

Abstract: A spherical gear pump that comprises two rotors, or geared spheres, with the teeth arranged around them in a circular band at right angles to their axis of rotation: the pump spheres are covered by close-fitting spherical cases or housings except at the central or most internal part of the connection between the gears on the two spheres, the fluid contained in the cavity created between the most external gears and the case or housing is moved during rotation from the intake to the outlet, one sphere is driven by its shaft and the other is dragged by the gearing between the two.

Abstract: A plastic toothed wheel for a toothed wheel pump comprises a wheel body (20) having external or internal teeth. To keep the weight of this toothed wheel as low as possible, its teeth (26) have at least one cavity (32) accessible from at least one end face of the tooth. Toothed wheel pumps having such toothed wheels for supplying and pressurizing engine oil in automotive vehicle engines avoid splashing losses caused by the cavities (32) by closing the cavities or filling them up with a temperature and media resistant foam material (66).

Abstract: A pump for moving a fluid has a housing with a internal chamber accommodating a pair of rotating pistons. Each piston has protrusions that register with pockets in the other piston in non-contact relation as the pistons rotate. A fluid accumulator in fluid communication with the pump holds a supply of fluid to prevent excessive pressure rise.