Working Chamber Surface Expressed Mathematically Patents (Class 418/150)
  • Patent number: 6494698
    Abstract: The invention relates to a rotary piston machine which can function as a pump, compressor or motor. A cycloid power component and a correspondingly formed blocking component are in mutual engagement in said machine. The difference in the number of teeth between both components is one. The volume of the working chambers (16) thus created attains a maximum and a minimum level at each rotation owing to the synchronous rotation of said power component and blocking component.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: December 17, 2002
    Inventor: Felix Michael Arnold
  • Patent number: 6368087
    Abstract: A scroll-type compressor includes a fixed and an orbiting scroll each having an end plate and a spiral element on the end plate and interfits with each other. A first transition line at a widened-starting portion of the spiral element between an interior wall and a tip surface comprises a first upper arc connecting to an upper, interior involute wall starting point and a second upper arc connecting to an upper, exterior involute wall starting point and a straight line. A second transition line at the widened-starting portion between the interior wall and a base surface comprises a first lower arc connecting to a lower, interior involute wall starting point and a second lower arc connecting a lower, exterior involute wall starting point and a straight line.
    Type: Grant
    Filed: February 7, 2001
    Date of Patent: April 9, 2002
    Assignee: Sanden Corporation
    Inventors: Toshiyuki Kikuchi, Ko Tsukamoto
  • Patent number: 6368091
    Abstract: The moment Mo of unbalanced forces Fr of a screw rotor A1 is reduced by adjusting the number of thread leads of a threaded portion 2 of the screw rotor A1 to (an integer +0.5). The amount of unbalance for keeping a state of dynamic balance thereby decreases, and the drilling of a thread e for keeping the state of the dynamic balance is made easier.
    Type: Grant
    Filed: September 22, 2000
    Date of Patent: April 9, 2002
    Assignee: Taiko Kikai Industries Co., Ltd.
    Inventor: Masaru Mito
  • Patent number: 6322334
    Abstract: The present invention relates to a rotary piston system mounted within an engine or a pump and characterized in that a piston moves inside a housing, thus reducing or enlarging closed spaces. The piston is an oloid element rotating about its axis. The internal space consists of two identical shells contiguously assembled along the equatorial planes thereof. The space defined by the shells inside the housing has an enveloping surface resulting from the biaxial rotation of the oloid element, the maximum diameter of which corresponds to its longitudinal profile.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: November 27, 2001
    Inventor: Thomas Klipstein
  • Publication number: 20010018028
    Abstract: A scroll-type compressor includes a fixed and an orbiting scroll each having an end plate and a spiral element on the end plate and interfits with each other. A first transition line at a widened-starting portion of the spiral element between an interior wall and a tip surface comprises a first upper arc connecting to an upper, interior involute wall starting point and a second upper arc connecting to an upper, exterior involute wall starting point and a straight line. A second transition line at the widened-starting portion between the interior wall and a base surface comprises a first lower arc connecting to a lower, interior involute wall starting point and a second lower arc connecting a lower, exterior involute wall starting point and a straight line.
    Type: Application
    Filed: February 7, 2001
    Publication date: August 30, 2001
    Inventors: Toshiyuki Kikuchi, Ko Tsukamoto
  • Patent number: 6280168
    Abstract: An object of the present invention is to provide a multi-cylinder rotary compressor which can eliminate a number of balancers for preventing vibrations. Assuming that the mass eccentricity in a cylinder is m1×r1; the mass eccentricity in another cylinder is m2×r2; the mass eccentricity of a balancer attached to the lower side of a rotator is m3×r3; the mass eccentricity of another balancer attached to the upper side of the rotator is m4×r4; respective distances from the cylinder to another cylinder, the lower balancer and another balancer are L2, L3 and L4, when the balancing is attained with the expressions m1×r1+m4×r4=m2×r2+m3×r3, m4×r4×L4=m2×r2×L2+m3×r3×L3, and m1×r1=m2×r2, the lower balancer is eliminated and the mass eccentricity of the balancer is set to be not less than 20% and not more than 80% of m4×r4.
    Type: Grant
    Filed: June 30, 2000
    Date of Patent: August 28, 2001
    Assignee: Sanyo Electric Co., LTD
    Inventors: Kenzo Matsumoto, Manabu Takenaka, Tsuyoshi Higuchi, Kazuaki Fujiwara, Dai Matsuura
  • Patent number: 6257851
    Abstract: A generalized technique is provided for maximizing the volumetric displacement of a gas within a scroll compressor having a scroll set including a fixed scroll wrap and an orbiting scroll wrap. The scroll wraps are designed to minimize the generating radius Rg for at least the outer portion of the wrap and achieve a high generating radius for at least the inner portion of the wrap. The generating radius can be either evaluated as the absolute value or the mean value taken as an integration from the outer extremity of the wrap inward.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: July 10, 2001
    Assignee: Scroll Technologies
    Inventors: James W. Bush, Wayne P. Beagle, Mark E. Housman
  • Patent number: 6244843
    Abstract: An internal gear pump which improves the mechanical efficiency and the life and reduces noises by eliminating non-uniformity of the gaps between teeth. In the internal gear pump wherein the tooth spaces of the outer gear and the tooth tips of the inner gear form an epicycloid and the tooth tips of the outer gear and the tooth spaces of the inner gear form a hypocycloid, these cycloids are formed by four circles that roll on the pitch circle of each gear such that the gap between teeth in a region where the outer and inner gears mesh most deeply with each other is substantially equal to the gap between teeth in a region where the depth of mesh between the outer and inner gears are the shallowest.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: June 12, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Toshiyuki Kosuge
  • Patent number: 6236897
    Abstract: This invention includes the derivation of the exact mathematical expressions for the curvature, either cardiocle or expanded cardioid, of the casing of the springless eccentric rotor vane pump, thereby facilitating the precision manufacture of the curved surfaces of the casing using CNC techniques. As a result, the capacity and accuracy of the eccentric rotor vane pump is greatly improved. As the section manufacture and assembly of the casing becomes possible, the mass production of large-sized pumps of 1-meter or larger diameter is now attainable, hitherto regarded as almost impossible, and therefore production cost is also reduced. The unique design which positions the axis of eccentricity in the lower central part of the axis of rotor rotation results in increase in the rotation speed of the rotor, and leads to reduction of friction between the vane ends and the curved surface of the casing as the weight of the vane does not affect the movement of the rotor.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: May 22, 2001
    Inventors: Dae Sung Lee, Yong Hee Park
  • Patent number: 6227832
    Abstract: The invention pertains to a rotary piston machine in which a rotor rotates in an enclosure and radially movable slides in the rotor form chambers of varying volume between the enclosure and the rotor, wherein an even number of slides is provided and mutually opposing slides are joined together into a rigid unit.
    Type: Grant
    Filed: May 16, 2000
    Date of Patent: May 8, 2001
    Inventor: Michael Rechberger
  • Patent number: 6220840
    Abstract: A fluid displacement apparatus is provided. The apparatus can be in the form of a scroll element for a scroll-type fluid compressor. The apparatus has first and second scrolls. The scrolls themselves, as well as the space between the scrolls may be defined by a spiral shape. The spiral shape may have either a constant pitch or a non-constant pitch.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: April 24, 2001
    Assignee: Sanden International (U.S.A.), Inc.
    Inventors: John L. Calhoun, David W. McClung
  • Patent number: 6220837
    Abstract: A progressing cavity pump adapted for use in pumping liquid/solid mixtures with a solid content of about 50% has a single start helical rotor and a two start helical stator bore. The ratio of the eccentricity of the rotor to its minor diameter is about 1:4.9. The ratio of the eccentricity of the rotor to the stator lead is about 1:13.3. The pump may be truck mounted and used for pumping explosives.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: April 24, 2001
    Assignee: Mono Pumps Limited
    Inventor: Roger Lawton Naylor
  • Patent number: 6152701
    Abstract: The present invention relates to a method for designing handling systems such as pipeline systems for fluid products such as emulsions and dispersions which deteriorate at elevated temperature and pressure. The method of the present invention comprises the steps of providing a pipeline having a fluid inlet point and a fluid discharge point and at least one pump for transporting the fluid from the fluid inlet point to the fluid discharge point, selecting one of a maximum pressure drop to be encountered by the fluid as it travels from the fluid inlet point to the fluid discharge point and a maximum volume of fluid to be handled by the system, and operating the system in accordance with the following equation: ##EQU1## where B is the maximum allowable shear rate from a first fluid inlet point to a second fluid discharge point, D is the diameter of the pipeline, and Q is the volume of fluid to be transported between the fluid inlet point and the fluid discharge point.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: November 28, 2000
    Assignee: Intevep, S.A.
    Inventors: Mariano Eurique Gurfinkel Castillo, Gustavo A Nunez, Geoff McGrath
  • Patent number: 6139299
    Abstract: The point of tangency of the tip circle of the male rotor and the root circle of the female rotor is used as a starting point in generating the series of curves defining the male and female conjugate rotor profiles. The present invention provides: reduced viscous drag through the use of a departure angle; strengthened female lobes by controlling thickness along the pitch circle; opened root of male rotor to enhance manufacturability and tool life; a tortuous leakage path for gas traveling from a high pressure thread to a low pressure thread; better control of root diameter; and control of the pressure angle independently of the other variables.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: October 31, 2000
    Assignee: Carrier Corporation
    Inventors: Keshava B. Kumar, James W. Bush
  • Patent number: 6116879
    Abstract: A pair of rotors (1,3) includes tooth parts (7,9) with a cycloid tooth profile curve and tooth bottom pans (11,13), and are engaged with each other. A housing (2) includes rotor chambers (2a) for rotatably accommodating the rotors (1,3), a suction port and a delivery port. Tips of the tooth parts (7,9) of the rotors (1,3) respectively have top parts (15,17) with a predetermined arc length (W.sub.1) which are cut to have a diameter (D.sub.2) smaller than a diameter (D.sub.1) of the tips of the predetermined cycloid tooth profile curve, and a diameter of the rotor chambers (2a) is made small.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: September 12, 2000
    Assignee: Tochigi Fuji Sangyo Kabushiki Kaisha
    Inventor: Masao Teraoka
  • Patent number: 6099261
    Abstract: A roller vane stage (10) for a fuel pump (80) includes an inlet plate (12), an outlet plate (14), and a spacer (16) held therebetween, the spacer having an eccentric inner surface (20) defining a rotor space (18) therein. The roller vane stage (10) further includes a rotor (30) mounted for rotation within the rotor space (18) and the rotor has a plurality of lobes (40), wherein each lobe contains an associated roller (42). Driver slots (44) located in the rotor (30) have a depth less than the thickness (h) of the rotor. Center outlet port (26) in the outlet plate (14) is shaped such that a lobe (40) and its respective roller (42) remains in fluid communication with the center outlet port almost until the lobe begins to communicate with inlet ports (22, 24) in the inlet plate (12).
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: August 8, 2000
    Inventor: Gary Worden
  • Patent number: 6099281
    Abstract: This design utilizes spherical balls that function as pumping members and also function as bearing loads. The housing includes channels that are used to convert rotary motion to true linear reciprocating motion relative to the center of operation by use of modified involute profile curves. The channels have an enlarged radius of curvature, four (4) contact point designs, and an arch design depending upon application and loads, etc. A variable vane shaft and variable seal plug have a make-before-break design that eliminates damaging high pressure spikes due to the trapped fluid. The vane is used to vary and control pumping arc by directing the high and low pressures. A rotor disclosed has an angle and slots that are designed to align with tangent of the involute curve. The variable displacement disclosed herein is varied by varying the pumping arc thereby causing more or less fluid to be pumped from inlet pressure to inlet pressure which actually affects displacement and input power required.
    Type: Grant
    Filed: September 4, 1998
    Date of Patent: August 8, 2000
    Inventor: James Edward Sobel
  • Patent number: 6077059
    Abstract: An oil pump rotor in which there is formed an inner rotor 10 having n teeth, the tips of the teeth prescribed by an epicycloid curve generated by a first outer rotating circle Ei which rotates along the base circle Bi of inner rotor 10, and the tooth spaces prescribed by a hypocycloid curve generated by a first rotating circle Hi which turns along the base circle Bi of inner rotor 10, and an outer rotor 20 having n+1 teeth, the tooth spaces prescribed by an epicycloid curve generated by a second rotating circle Eo which turns along the base circle Bo of outer rotor 20 and the tips of the teeth prescribed by a hypocycloid curve generated by a second inner rotating circle Ho which rotates along the base circle Bo of outer rotor 20; wherein each of the rotors are formed to satisfy:Do>Di, di>dowhere Di, di, Do, and do designate the diameters of Ei, Hi, Eo, and Ho, respectively.
    Type: Grant
    Filed: March 19, 1998
    Date of Patent: June 20, 2000
    Assignee: Mitsubishi Materials Corporation
    Inventor: Katsuaki Hosono
  • Patent number: 6036462
    Abstract: A rotary vane machine having a rotary-linear vane guidance structure, including a translation ring disposed at each axial end of the machine, the translation ring rotating around a fixed hub, with the fixed hub being eccentric to a rotor shaft axis, with the rotor spinning around the rotor shaft axis which is a fixed rotational axis relative to a stator cavity. A plurality of vanes are disposed in a corresponding plurality of vane slots in the rotor, each of the vanes having a tip portion and a base portion, with the base portion having a protruding tab extending from each axial end therefrom. A plurality of linear channels are formed in each translation ring, wherein the protruding tabs extending from the base portion of each of the plurality of vanes communicate with a respective linear channel in the translation ring, whereby the rotor rotation causes rotation of the vanes and a corresponding rotation of the translation ring.
    Type: Grant
    Filed: July 2, 1997
    Date of Patent: March 14, 2000
    Assignee: Mallen Research Ltd. Partnership
    Inventor: Brian D. Mallen
  • Patent number: 5934891
    Abstract: The screw pump (1) has a driving screw (6) and at least one side screw (7), which are placed in a screw channel (5) in the pump body (2), between a suction space (3) and a pressure space (4). At least one of the clearances between the surfaces of the driving screw, side screws and screw channel is larger in the areas close to the suction and pressure spaces than the corresponding clearance in the middle portion of the pump channel. The magnitude of the clearances is so fitted that the total leakage flow (V) between the suction and pressure spaces through the clearances is substantially the same for all angles of rotation of the screws (6,7). Preferably the clearance fit is achieved by reducing the diameter of the screw at its ends so that the change in the external diameter of the reduced portion has at least two different values.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: August 10, 1999
    Assignee: Kone Oy
    Inventor: Raimo Pelto-Huikko
  • Patent number: 5908289
    Abstract: The gear machine according to the invention includes a driving gear wheel (1) and a driven gear wheel (2) having meshing gear teeth (21,22) having a special novel shape designed to provide improved gear wheel kinematics as well as minimal volume flow rate fluctuations. A correction of the gear teeth side geometry is performed by local limited adjustment of the basic transmission function i for eliminating volume flow rate fluctuations so that a discontinuity-free transmission is attained which results in an improved motion of the driven gear wheel with reduced acceleration changes. In order to accomplish this improvement in kinematics, the shape of the flanks or sides (25,26) of the engaging or meshing gear teeth (21,22) is such that the transmission function i depends on a spacing (g.sub..alpha.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: June 1, 1999
    Assignee: Robert Bosch GmbH
    Inventors: Dietmar Schwuchow, Karl-Heinz Hirschmann, Gisbert Lechner, Klaus Riedl
  • Patent number: 5888058
    Abstract: A positive-displacement machine with movable sealing members (4) including at least one encased system which essentially comprises a casing consisting of a cylindrical tubular portion (1) with a non-circular directrix (10), and two sealing flanges; and a cylindrical piston (2) having a circular directrix (20) and being provided with grooves (3) for guiding the sealing members in the piston, said piston having a rotary connection to the casing. The directrix of the tubular portion of the casing consists of n arcs of conformity and n bows restricting the motion of the sealing members in the grooves. The bows are defined by solving a set of equations.
    Type: Grant
    Filed: August 6, 1997
    Date of Patent: March 30, 1999
    Inventors: Andre Leroy, Jean-Marie Flamme
  • Patent number: 5876193
    Abstract: The present invention relates to an oil pump rotor provided with an inner rotor 10 to which n (n is a natural number) outer teeth 11 are formed, an outer rotor 20 to which n+1 inner teeth 21 are formed which engage with each of the outer teeth 11, and a casing 30 in which an intake port 31 for taking up fluid and an expulsion port 32 for expelling fluid are formed, wherein:the outer teeth of inner rotor are formed by alternately combining an epicycloid curve and a hypocycloid curve, the epicycloid curve being generated as an orbit of the point on a circle which rolls along the outside of the base circle without slipping, and the hypocycloid curve being generated as an orbit of a point on a circle which rolls along the inside of the base circle without slipping; the alternately combined curve being generated under the following condition, where E is the diameter of the circle which rolls along the outside of the base circle, and H is the diameter of the circle which rolls along the inside of the base circle:0.
    Type: Grant
    Filed: January 15, 1997
    Date of Patent: March 2, 1999
    Assignee: Mitsubishi Materials Corporation
    Inventors: Katsuaki Hosono, Manabu Katagiri
  • Patent number: 5836752
    Abstract: A fluid displacement apparatus is provided. The apparatus can be in the form of a scroll element for a scroll-type fluid compressor. The apparatus has first and second scrolls. The scrolls themselves, as well as the space between the scrolls may be defined by a spiral shape. The spiral shape may have either a constant pitch or a non-constant pitch.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: November 17, 1998
    Assignee: Sanden International (U.S.A.), Inc.
    Inventors: John L. Calhoun, David W. McClung
  • Patent number: 5836754
    Abstract: In a screw fluid machine including male and female rotors which are engaged with each other, a casing for accommodating both the male and female rotors, fluid working rooms which are formed by the male and female rotors and the casing, and fluid inlet and outlet ports which are provided in the casing so as to intercommunicate with one end portion and the other end portion of the working rooms, the helix angle of the screw gear constituting each of the male and female rotors is set to be continuously varied in a helix advance direction. Further, the screw gear is designed so that the peripheral length of a pitch cylinder in a helix advance direction on a development of a tooth-trace rolling curve on the pitch cylinder of the screw gear can be expressed by a substantially monotonically increasing function.
    Type: Grant
    Filed: March 13, 1997
    Date of Patent: November 17, 1998
    Assignee: Diavac Limited
    Inventors: Masayuki Ozaki, Isao Akutsu
  • Patent number: 5813844
    Abstract: The present invention relates to an oil pump rotor for an oil pump provided with an inner rotor 10 to which n (n is a natural number) outer teeth 11 are formed, an outer rotor 20 to which n+1 inner teeth 21 are formed which engage with each of the outer teeth 11, and a casing 30 in which an intake port 31 for taking up fluid and an expulsion port 32 for expelling fluid are formed, wherein:the outer teeth 11 of inner rotor 10 are formed along an envelope described by a generated group of circles having centers positioned on a trochoid curve generated within the limits satisfying the following expression:0.15.ltoreq.n.multidot.R/(p.multidot.D).ltoreq.0.25where D is the diameter of the circle which passes through each of the tips of the outer teeth and R is the radius of the generated circle measured in millimeters, while p is .pi..
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: September 29, 1998
    Assignee: Mitsubishi Materials Corporation
    Inventors: Katsuaki Hosono, Manabu Katagiri
  • Patent number: 5800151
    Abstract: The transverse tooth profile of a screw rotor which meshes with a companion screw rotor is defined by a tooth root circular arc, an outer circumferential circular arc, and two curves interconnecting the tooth root circular arc and the outer circumferential circular arc. One of the curves is defined by a trochoid curve generated by a point on an outer circumferential surface of the companion screw rotor. Alternatively, the curve may comprise two curve segments, and one of the two curve segments comprising a tooth tip arc which is defined as an arc having a radius of curvature equal to or smaller than the difference between a radius of curvature of the outer circumferential circular arc and a radius of a pitch circle of the tooth profile, and the other of the two curve segments comprising a curve connected to the tooth root circular arc and determined by a curve generated by the tooth tip arc of the companion screw rotor.
    Type: Grant
    Filed: September 3, 1997
    Date of Patent: September 1, 1998
    Assignee: Ebara Corporation
    Inventors: Takeshi Kawamura, Kiyoshi Yanagisawa, Shigeyoshi Nagata
  • Patent number: 5772419
    Abstract: A hydraulic machine with two displacement elements (2,3) rotatably movable relative to one another, namely, a gearwheel (2) and an annular gear (3) of which the number of teeth is one more than the number of teeth (N) of the gearwheel (2), in which machine the tooth form of a least one displacement element (2,3) is defined at least over sections by a trochoid-type curve T=f (RC, E, RT) as the function of a reference circle radius RC, an eccentricity E and a generating circle radius RT. In a machine of that kind, it is desirable for the efficiency and the running behaviour to be improved and for wear to be reduced. To that end, of the parameters (RC, E, RT) determining the function f, at least one parameter varies in the circumferential direction periodically with the period of a tooth pitch (Z).
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: June 30, 1998
    Assignee: Danfoss A/S
    Inventors: Gunnar Lysh.o slashed.j Hansen, Hans Christian Petersen
  • Patent number: 5762484
    Abstract: The pump has an inner rotor bounded by an outer peripheral shape which is generated by moving a first circle around a first trochoid. The inner rotor is mounted for rotation about a first axis. The pump also has an outer rotor mounted for rotation about a second axis which is offset from the first axis. The outer rotor is bounded by an inner peripheral shape which is generated by moving a second circle around a second trochoid.
    Type: Grant
    Filed: October 21, 1996
    Date of Patent: June 9, 1998
    Assignee: T&N Technology Limited
    Inventor: Gavin P. Whitham
  • Patent number: 5758501
    Abstract: A sliding-blade vapor engine has a vortex boiler, condenser, blower and oval-shaped expander and pump chambers with cylindrical expander and pump rotors rotatably mounted eccentrically therein. Each rotor has at least two rectangular blades slidably mounted in slots extending through the cylindrical rotor in mutually perpendicular relation and each blade is independently movable relative to the other in a radial direction. Each blade has a guide element extending from opposed sides and through the opposed end walls of the respective rotor which are slidably received in guide grooves in the respective chamber end walls. The rotors are connected together by shafts in concentric relation whereby rotation of the expander rotor causes simultaneous rotation of the pump rotor and the guide elements traveling in the guide grooves cause the blades to extend and retract radially with their outer ends following the inner periphery of the respective chamber side wall with a constant minimum clearance.
    Type: Grant
    Filed: January 2, 1996
    Date of Patent: June 2, 1998
    Inventors: Olga Jirnov, Alexei Jirnov
  • Patent number: 5711268
    Abstract: A rotary vane internal combustion engine wherein the section of the rotor housing where ignition takes place is formed in the shape of a circular arc matching the curvature of the rotor, with the balance of the housing periphery being composed of a series of tangent arcs to define an elliptical shape that is continuously concave and has no drastic changes in curvature. The rotor and housing are "stretched" along their axial dimensions so that each combustion chamber has an axial measurement substantially greater than its circumferential measurement, and each segment of the rotor surface between adjacent vanes has formed therein a plurality of combustion chamber pockets spaced from one another along the axial dimension of the rotor and each provided with a spark plug.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: January 27, 1998
    Assignee: C & M Technologies, Inc.
    Inventor: Carl J. Holdampf
  • Patent number: 5702242
    Abstract: A vane pump including a rotor, which is arranged within a cam ring located in the pump housing, and which carries a plurality of radially displaceable vanes which are also displaceable along the inner double-symmetrical contour of the cam ring, with the inner contour defining two diametrically opposite pump chambers and with each chamber being divided in three sections forming, respectively, a suction region, a pressure region, and a separation region between the suction and pressure regions.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: December 30, 1997
    Assignee: Luk Fahrzeug-Hydraulik GmbH & Co.
    Inventors: Thomas Nied-Menninger, Randolf Kortge, Bernd Denfeld
  • Patent number: 5697772
    Abstract: The transverse tooth profile of a screw rotor which meshes with a companion screw rotor is defined by a tooth root circular arc, an outer circumferential circular arc, and two curves interconnecting the tooth root circular arc and the outer circumferential circular arc. One of the curves is defined by a trochoid curve generated by a point on an outer circumferential surface of the companion screw rotor. Alternatively, the curve may comprise two curve segments, and one of the two curve segments comprising a tooth tip arc which is defined as an arc having a radius of curvature equal to or smaller than the difference between a radius of curvature of the outer circumferential circular arc and a radius of a pitch circle of the tooth profile, and the other of the two curve segments comprising a curve connected to the tooth root circular arc and determined by a curve generated by the tooth tip arc of the companion screw rotor.
    Type: Grant
    Filed: April 3, 1996
    Date of Patent: December 16, 1997
    Assignee: Ebara Corporation
    Inventors: Takeshi Kawamura, Kiyoshi Yanagisawa, Shigeyoshi Nagata
  • Patent number: 5682793
    Abstract: The present invention relates to a pair of meshed involute gears one of which has work teeth, their tooth-tip circle is larger than that of the said gear, the other has the grooves engaged with the said working teeth. The working teeth and the grooves have the same characters of equal periphery of meshing and rotating as the said involute gears. This composite construction of the gear named "the meshing type rotors" can be used in making internal combustion engine, fluid (liquid or gasous) pump and motor, vacuum pump, conditioner/refrigerator/compressor and hydraulic variator.
    Type: Grant
    Filed: May 9, 1996
    Date of Patent: November 4, 1997
    Inventor: Zhenyi Liao
  • Patent number: 5674063
    Abstract: In a screw fluid machine including male and female rotors which are engaged with each other, a casing for accommodating both the male and female rotors, fluid working rooms which are formed by the male and female rotors and the casing, and fluid inlet and outlet ports which are provided in the casing so as to intercommunicate with one end portion and the other end portion of the working rooms, the helix angle of the screw gear constituting each of the male and female rotors is set to be continuously varied in a helix advance direction. Further, the screw gear is designed so that the peripheral length of a pitch cylinder in a helix advance direction on a development of a tooth-trace rolling curve on the pitch cylinder of the screw gear can be expressed by a substantially monotonically increasing function.
    Type: Grant
    Filed: August 17, 1995
    Date of Patent: October 7, 1997
    Assignee: Diavac Limited
    Inventors: Masayuki Ozaki, Isao Akutsu
  • Patent number: 5667370
    Abstract: A screw displacement pump has a chamber. Inlet and outlet are provided for the admission of gas to and discharge of gas from the chamber. Intermeshing screw members rotatably mounted within the chamber for delivering the gas from the inlet to outlet, wherein the pitch of the screw members decrease continuoulsy from the inlet end thereof to the outlet end thereof to cause compression of the gas being delivered. The continuous reduction in the pitch distance from the inlet end to the outlet end is generated by the following relationship:Pitch at the outlet end/Pitch at the inlet end<.pi..sub.i /kwhere, .pi..sub.i =pressure ratio calculated under the condition that the process is effected in a adiabatic and the work done is constant, C.sub.1 =0, and k is gas constant.
    Type: Grant
    Filed: August 22, 1995
    Date of Patent: September 16, 1997
    Assignee: Kowel Precision Co., Ltd.
    Inventor: Kisu Im
  • Patent number: 5658138
    Abstract: A rotary pump (10) of the type having inner and outer rotary components (32, 30) which rotate in the same direction at the same speed, the inner rotary component (32) being located within the outer rotary component (30), and in which the outer rotary component (30) has an annular wall (44), abutments (46) and recesses (50) between the abutments (46), and contact bodies (48) formed on the abutments (46) and being shaped as a major segment of an ellipse; and in which the inner rotary component (32) has an inner body (60) with abutments (64) located within respective outer recesses (50), and receiving the outer wall abutments (46) and contact bodies (48), the outer component (30) having a rotary axis, located along its central axis, a drive shaft (36) connected to the inner body (32) and located along its central axis, the outer and inner axes being parallel to and spaced from one another so that the inner component (32) is located offset from the center of the outer component (30), the inner body recess surface
    Type: Grant
    Filed: March 14, 1996
    Date of Patent: August 19, 1997
    Inventors: George F. Round, Viljo K. Valavaara, Lixin Peng
  • Patent number: 5639230
    Abstract: A gear pump or motor, has two rotatively guided toothed or gear wheels in a housing, the teeth of which are mutually engaged and separate a compression chamber from a suction or discharge chamber. Depending on the rotation angle .phi.1 of a torque-transmitting gear wheel, an instantaneous hydraulic medium volume flow V is displaced and the mutually engaging gears wheels have a gear ratio i=.phi.1/.phi.2, where .phi.2 is the rotation angle of the non-torque transmitting gear wheel. In order to avoid pressure fluctuations and the resulting sound projection, the instantaneous gear ratio i over the whole angle of rotation .phi.1 of the torque-transmitting gear wheel is selected in such a way that the non-torque-transmitting gear wheel is driven at a constantly changing, periodically returning angular speed by tooth pitch, thus totally or partially compensating by an output increase or reduction the volume flow pulsation caused by the constant change in the position of the sealing limit at the teeth contact point.
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: June 17, 1997
    Inventors: Gisbert Lechner, Karl-Heinz Hirschmann
  • Patent number: 5628626
    Abstract: A hydraulic machine is disclosed, with a gearwheel, which has a midpoint (6) and a predetermined number of external teeth, and an annular gear, which has a midpoint (7) offset by an eccentricity (E) with respect to the midpoint (6) of the gearwheel and a number of internal teeth which exceeds by one the number of external teeth, the gearwheel and annular gear orbiting and/or rotating relative to one another and at least the form of the external teeth being created using a set of circles (30, 30'; 35, 35') lying with their midpoints (P1-P6; P1'-P6') on a trochoid (36, 37). It is desirable for the efficiency, service life and noise properties of such a machine to be improved. To that end, at least two trochoids (36, 37), displaced relative to one another in the circumferential direction, are provided for generating a tooth profile, the rolling circles (28, 33) of which and the base circles (27, 32) of which differ from one another.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: May 13, 1997
    Assignee: Danfoss A/S
    Inventor: Gunnar L. Hansen
  • Patent number: 5624250
    Abstract: An improved tooth profile for compressor screw rotors is disclosed. In the tooth profile, the following-side first curve of the male rotor is generated using a generation parameter of a quadratic function f(x)=a.sub.10 x.sup.2 +b.sub.10 x+c.sub.10 whose constants are optimized to meet specified constraint conditions. The above constraint conditions include an increased pressure angle for achieving good cutting condition of the rotors, a sealing surface suitable for minimizing the negative torque applied to a following rotor due to the gas pressure in the trapped pocket volume defined between the rotors, a large surface contact between the two rotors for improving the sealing effect as well as the durability of the rotors, and a minimized specific sliding at the driving force transmission part of the rotors for reducing the operational vibration and noise of the rotors.
    Type: Grant
    Filed: September 20, 1995
    Date of Patent: April 29, 1997
    Assignee: Kumwon Co., Ltd.
    Inventor: Kil-Won Son
  • Patent number: 5605451
    Abstract: A fluid apparatus of an internal gear type comprising an internal gear 3 rotatively mounted in a housing 1, an external gear 5 meshing with said internal gear 3, and a crescent partition piece disposed between the both gears, each tooth profile of said both gears 3 and 5 being defined by a line equidistant from an inner cycloid described by a rolling circle, the diameter of which is equal to a radius of the intermeshing pitch circle of the internal gear, whereby the load applied to the tooth surfaces between the meshing internal gear and external gear and thus the tooth-contact stress can be reduced, and wear of tooth surfaces and generating noise can also be minimized.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: February 25, 1997
    Assignee: Tokyo Sintered Metal Company Limited
    Inventor: Masaoki Saitoh
  • Patent number: 5562434
    Abstract: A scroll compressor includes a stationary scroll and an orbiting scroll having respective wrap elements in engagement with each other. Each of the stationary and orbiting wrap elements has a tip seal groove defined therein and having opposing internal and external walls that are formed so as to represent two involute curves having different phases, respectively.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: October 8, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masahiko Makino, Michio Yamamura, Masafumi Fukushima, Kunio Iwanami
  • Patent number: 5558509
    Abstract: A sliding-blade water jet propulsion apparatus has an oval-shaped chamber and a water channel extending generally tangential to the chamber with a cylindrical rotor rotatably mounted eccentrically in the chamber. The rotor has at least two rectangular blades slidably mounted in slots extending through the cylindrical rotor in mutually perpendicular relation and each blade is independently movable relative to the other in a radial direction. Each blade has a guide element extending from opposed sides and through the opposed end walls of the rotor which are slidably received in guide grooves in the chamber end walls. The guide elements traveling in the guide grooves cause the blades to extend and retract radially with their outer ends following the inner periphery of the chamber side wall and a portion of the water channel with a constant clearance.
    Type: Grant
    Filed: April 6, 1995
    Date of Patent: September 24, 1996
    Inventors: Olga Jirnov, Alexei Jirnov
  • Patent number: 5558510
    Abstract: A scroll compressor includes a stationary scroll and an orbiting scroll having respective wrap elements in engagement with each other. An inner end portion of an internal wall of one of the wrap elements is partially shaped to represent a curve identical to or approximate to an envelope curve which is obtained through circular translation of a circular arc connected with an external wall of the other wrap element. The radius of the circular arc is so chosen as to increase the shortest distance a.sub.x from each of points on the curve to the external wall of the one wrap element towards the inner end of the one wrap element.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: September 24, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masahiko Makino, Michio Yamamura, Masafumi Fukushima, Kunio Iwanami
  • Patent number: 5558511
    Abstract: A sliding vane machine with a cylindrical rotor (11) eccentrically placed in a housing, the rotor being rotatably mounted in the housing with its periphery in contact with the interior of the housing at one point and being provided with a number of vanes (13). The vanes are guided in grooves (12) in the rotor (11) for essentially radial movement and delimit, together with the rotor (11) and the housing (1), chambers (14) for transporting a medium from an inlet opening (15) to a delivery opening (16). The movement of each of the vanes (13) is guided by at least one guide (17, 18), which runs along a guide race (19) in the housing. The guide race (19) and/or the interior of the housing (1) has such a shape, that the radially distal end of each vane (13) follows the contour of the interior of the housing (1).
    Type: Grant
    Filed: March 3, 1995
    Date of Patent: September 24, 1996
    Assignee: Fanja Ltd.
    Inventor: Lars G. Hedelin
  • Patent number: 5513967
    Abstract: The surface of a central section of a spiral element formed on a stationary or a movable scroll unit of a scroll type compressor is determined through the steps of locating an outer wall surface changing point G in a first polar coordinate system X, Y having a first origin O, drawing a circle Cs with its center at the first origin O and with a diameter corresponding to the orbital radius e of the orbiting motion of the movable scroll unit, locating a contact point P at a desired contact angle .beta. on the circle Cs, drawing a straight line m passing through the contact point P and the first origin O, drawing a straight line I passing the outer wall surface changing point G and inclined at a predetermined angle .alpha.
    Type: Grant
    Filed: March 15, 1995
    Date of Patent: May 7, 1996
    Assignee: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
    Inventors: Akira Nakamoto, Masakazu Obayashi, Kazuhiro Nomura, Hirouki Gennami
  • Patent number: 5460495
    Abstract: A screw rotor for fluid handling devices configured to reduce the area of blowholes virtually without relationship to the length of the sealing line by selecting specific profile shapes of the addendum of the female rotor and the dedendum on male rotor. Further, the screw rotor configuration eliminates semi-occluded pockets forming between the addendum of the female rotor and the dedendum of the male rotor.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: October 24, 1995
    Assignee: Mayekawa Mfg. Co.
    Inventors: Akira Matsui, Takayuki Kishi, Toshio Nishio, Keisuke Kasahara
  • Patent number: 5439359
    Abstract: A rotary positive displacement machine is formed by a male organ and a female organ that surrounds it. The male and female organs have helicoid surfaces of particular shapes and also have parallel axes. The male and female surfaces of the invention define a work chamber and the machine has n.sub.m +1 permanently existing points of contact between the male and female profiles. Furthermore, the work chambers of the machine are closed such that the male and female surfaces defining the chambers contain a single point defining a tapered closure in a section where the closure point comes into contact with the n.sub.m +1 permanently existing points of contact.
    Type: Grant
    Filed: April 22, 1994
    Date of Patent: August 8, 1995
    Inventors: Andre Leroy, Jean M. Flamme
  • Patent number: 5431552
    Abstract: A sliding vane pump having an inside liner with a constant radius pump arc and a constant radius stop arc, connected together by cycloidal arcs. The liner has inlet slots arranged extending around a perimeter of a liner extending into the pump arc for maximum filling of the pumping volume. A herringbone-shaped slot arrangement is provided on a outlet side which increases vane life, increases sealing around the vanes on the outlet side, and decreases liner wear. A relief/fill porting arrangement is provided to pressurize the fluid in the pump chamber, or alternately to relieve pressure from the pump chamber. An improved thrust absorber is described particularly useful for truck mounting of the pump. An asymmetrical inside profile for the liner assists in pump operation by providing a fluid mathematical profile which approaches zero acceleration forces at the point of tangency.
    Type: Grant
    Filed: February 1, 1994
    Date of Patent: July 11, 1995
    Assignee: Corken, Inc.
    Inventors: James J. Davis, James D. Gray, Michael F. Hughes, Ronald A. Schuller, Michael W. Spidell, Alan P. Tiefenbrun
  • Patent number: 5427512
    Abstract: A scroll fluid machine in which, even if volute bodies on the orbiting side and on the fixed side are different in material from each other, the volute bodies can be brought to their respective strengths equal to each other, dimension can be miniaturized or reduced, and internal leakage is reduced so that an attempt can be made to improve performance. In the scroll fluid machine, a curve of either one of a orbiting outward curve and a orbiting inward curve of a volute body on the orbiting side is formed by an algebraic spiral expressed by the following equation in the form of polar coordinates r=a.multidot..theta..sup.k (here, r: radius vector, .theta.: angle of deviation, a: coefficient, k: exponent). This curve and any one of a fixed outward curve and a fixed inward curve of the volute body on the fixed side are arranged with a phase difference of about 180 degrees. Thicknesses of respective volute walls on the orbiting side and on the fixed side are adequately or suitably changed.
    Type: Grant
    Filed: December 17, 1992
    Date of Patent: June 27, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Hirokatsu Kohsokabe, Hiroshi Iwata, Kazuhiro Endoh, Yasuhiro Oshima