Form Patents (Class 74/462)
  • Patent number: 7770484
    Abstract: There are provided a resin double helical gear capable of reducing operation noises and vibrations of an ink jet printer, and a gear train for an ink jet printer using the same. The gear train 2 for an ink jet printer 1 includes an output gear 5 of a motor 3, a first idle gear 6 meshing with the output gear 5, a second idle gear 7 rotatable with the first idle gear 6, and a driven gear 8 which is mounted on a roller shaft 13 so as to be rotatable therewith and which meshes with the second idle gear 7, wherein a resin double helical gear 101 is used as each of the output gear and the first idle gear, and a spur gear is used as each of the second idle gear and the driven gear. The resin double helical gear may have a meshing relief portion 113 by cutting a chevron-shaped top portion 104 in a central portion 103 in face width directions, which is arranged in a butt portion 113 between a first die 108 and a second die 110, from a tooth crest to a portion near a bottom land so as to decrease a tooth thickness.
    Type: Grant
    Filed: July 17, 2008
    Date of Patent: August 10, 2010
    Assignee: Enplas Corporation
    Inventor: Toru Hagihara
  • Patent number: 7766634
    Abstract: A novel crescent gear pump and pump rotor set for a crescent gear pump. The rotor set includes an outer rotor with teeth having a composite profile formed over the portion adjacent their root to conform to a circular arc and formed over the portion adjacent their tip to conform to a hypocycloid arc. The unique shape allows for increased volumetric capacity of the rotor set, when compared to trochoidal rotor sets of the same size. Further, operating noise is reduced, as are pulsations in the output of the pump when compared to the same pump with a trochoidal rotor set.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: August 3, 2010
    Assignee: Magna Powertrain Inc.
    Inventors: Vasilios B. Liavas, Michal Nemec
  • Patent number: 7762155
    Abstract: A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: July 27, 2010
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: John M. Vranish
  • Patent number: 7735396
    Abstract: A rigid internal gear and a flexible external gear of a wave gear drive are spur gears of module m. The number of teeth of the external gear is smaller by 2n (n is a positive integer) than that of the internal gear. The deflection of the major axis of the elliptical rim neutral line on the principal cross-section of the external gear is set at 2?mn (?<1). On the principal cross-section, the meshing of both gears is approximated by rack meshing. The locus M of movement of a tooth of the external gear caused by the rotation of a wave generator is determined. A part AC of the locus M of movement from the inflection point A of the locus M of movement to the deepest position B of meshing is determined on the entering side of meshing of the teeth toward the major axis of the locus M of movement.
    Type: Grant
    Filed: June 21, 2004
    Date of Patent: June 15, 2010
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Shoichi Ishikawa, Noboru Takizawa
  • Patent number: 7698964
    Abstract: A gear having a thin-walled section formed on one end face among two end faces of a tooth in a tooth-width direction is provided. A portion of the thin-walled section is projected and formed so as to serve as an overhanging section. The overhanging section prevents backlash. A thickness T3 of the overhanging section, a thickness T2 of a tooth flank corresponding section, and a thickness T1 of a tooth crest corresponding section positioned therebetween satisfies the relation T1<T3<T2.
    Type: Grant
    Filed: July 2, 2007
    Date of Patent: April 20, 2010
    Assignee: Enplas Corporation
    Inventor: Noritake Kashimura
  • Patent number: 7694607
    Abstract: A wave gear drive comprises a circular rigid internal gear and a flexible external gear inside the rigid internal gear. A wave generator in the flexible external gear flexes the flexible external gear into an elliptical shape. The cross-section of the flexible external gear perpendicular to the axis at a point in the tooth trace direction of the flexible external gear is set as the main cross-section. The rigid internal gear and flexible external gear are gears with a module m, and the flexible external gear has a number of teeth that is smaller than the number of teeth of the rigid internal gear. The moving route M of a tooth of the flexible external gear with respect to a tooth of the rigid internal gear that accompanies rotation of the wave generator when meshing of the teeth in the main cross-section is approximated by rack meshing.
    Type: Grant
    Filed: January 11, 2007
    Date of Patent: April 13, 2010
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Shoichi Ishikawa, Noboru Takizawa
  • Publication number: 20100083724
    Abstract: An apparatus for extruding teeth in a blank includes a press that includes a lower die plate for supporting the blank thereon, and upper die plate that moves along an axis relative to the lower die plate. A mandrel, aligned with the axis, moves with the upper die plate along the axis, and includes die teeth which form gear teeth to net shape by back extrusion. An impingement ring, located between the upper die plate and the blank, has an opening that allows the die teeth of the mandrel to contact the blank, and includes a stinger that forces material of the blank toward the axis during the forming cycle.
    Type: Application
    Filed: October 3, 2008
    Publication date: April 8, 2010
    Inventors: Joseph Szuba, Rodney G. Whitbeck
  • Publication number: 20100077882
    Abstract: A coaxial gear set, in particular a hollow shaft gear set for industrial drive technology, having high power density, comprising a drive element (7), an element (3), and an output element, with a gear ratio and a transmission of a drive torque occurring between the drive element (7) and the output element via a plurality of radially movable tooth segments (5), an outer tooth flank contour (11.1, 11.2) of the tooth contour (6) of the tooth segments (5) and/or a flank contour (12.1, 12.2) of a gearing (13) of an inner gearing (15) of an internal wheel (1), relative to a gear axis (M), a tooth contour that allows surface contact in the engagement area comprising a logarithmic spiral.
    Type: Application
    Filed: March 5, 2008
    Publication date: April 1, 2010
    Applicant: WITTENSTEIN AG
    Inventor: Heiko Schreiber
  • Patent number: 7686734
    Abstract: An apparatus and method for finishing the mating surfaces of a gear set or gear train includes at least a first and a second rotatably connected gear element in dynamic, lubricated contact and rotating at different cycle rates. A hardness differential is employed between mating gear surfaces to balance surface damage imparted by friction and plastic deformation. The mating surfaces are of a hardness of at least approximately 70 on the Rockwell superficial hardness scale (70HR-30N), and are subjected to a polishing process, such as isotropic chemical finishing, to shape the surface asperity profile, thereby reducing accumulative damage due to friction and plastic deformation.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: March 30, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Gregory Mordukhovich, Avinash Singh
  • Publication number: 20100011895
    Abstract: In a gear (G1) according to the present invention, which is provided with a plurality of teeth (1) to be mated with teeth of a mating gear to thereby transmit a rotational motion, a predetermined region (A) in at least one tooth flank (7) of each tooth (1) is formed in a configuration such that, from at least one place in a tooth width direction on a crossing (8) of the tooth flank (7) and a tooth tip surface (3), the mating with the teeth of the mating gear is started with the point contact or the line contact shorter than the total tooth width, and thereafter, is gradually shifted to the line contact so that the length of contact line (10) thereof is sequentially increased as the line contact moves from a tooth tip surface (3) side toward a tooth root side.
    Type: Application
    Filed: September 25, 2009
    Publication date: January 21, 2010
    Applicant: ENPLAS CORPORATION
    Inventors: Kenji OHMI, Yasutaka Kawakami
  • Publication number: 20100000357
    Abstract: The invention relates to a gear pair consisting of a crown gear (1) and of a pinion gear (2) provided in the form of a spur gear with an axis crossing angle of 90°. According to the invention, the teeth (3) of the pinion gear (2), in order to reduce an undercut of the teeth (5) of the crown gear (1), have a pressure angle, which increases from the outside inward in a radial direction with regard to the crown gear (1), or in the event of a constant pressure angle, have a profile offset, which decreases from the outside inward in a radial direction with regard to the crown gear (1).
    Type: Application
    Filed: December 9, 2005
    Publication date: January 7, 2010
    Applicant: THYSSENKRUPP PRAZISIONSSCHMIEDE GMBH
    Inventors: Peter Gutmann, Heinrich Stettinger, Frank Zerling
  • Publication number: 20090255359
    Abstract: A rotational drive transmission mechanism used in an image forming apparatus for transmitting rotational drive force using an internal gear and an external gear having involute tooth profiles, includes photoreceptor drum drive couplings for transmitting rotational drive force to photoreceptor drums and a transfer drive coupling for transmitting rotational drive force to an intermediate transfer belt drive roller. The internal gears provided for these are so formed that all the drive vectors of the rotational drive force transmitted to the teeth of either the internal gear or the external gear in mesh with the internal gear, are made uniform so as to be oriented either outwards from the center of the rotational axis or inwards toward the center of the rotational axis, equivalently relative to the center of the rotational axis.
    Type: Application
    Filed: March 30, 2009
    Publication date: October 15, 2009
    Inventors: Tetsushi ITO, Yoshikazu Harada, Norio Tomita, Noriaki Taguchi, Shuichi Mochizuki
  • Publication number: 20090229395
    Abstract: An improved structure of power transmission apparatus, includes a power source supplier connected with a transmission shaft, a first driven element pivotally connected to the transmission shaft, a second driven element pivotally connected to a driven shaft and intermeshing with the first driven element, wherein both the first driven element and the second driven element are a gear being appropriately defined as a spur gear with a gear profile curve and having a pitch cone angle of a tooth, the pitch cone angle forming a first tooth curve and a second tooth curve, the pitch cone angle of the first driven element being in upside down relation to that of the second driven element to facilitate the first driven element and the second driven element being able to intermesh closely and smoothly with each other.
    Type: Application
    Filed: November 18, 2008
    Publication date: September 17, 2009
    Inventors: Tsang-Lin Hsu, Heng-I Lin, Yao-Chung Tsai
  • Publication number: 20090234540
    Abstract: A method and a device for measuring the angular position, between two steering locks, of a steering wheel of a vehicle, includes equipping the vehicle with a main gearing (4, 5) designed, once the vehicle has started, to make it possible to calculate the absolute angular position of the steering wheel from data provided by a first angular sensor (15) associated with this main gearing. According to the invention, the vehicle is additionally equipped with an auxiliary gearing composed of one of the gearwheels (5) of the main gearing, of a third gearwheel (8), and of intermediate elements (6, 7, 9) for sequentially driving the third gearwheel (8) that are able to make it possible, upon starting of the vehicle, to measure the angular position of the third gearwheel (8) via a second angular sensor (16) associated with this gearwheel.
    Type: Application
    Filed: March 26, 2007
    Publication date: September 17, 2009
    Inventors: Michel Collet, Eric Servel, Yves Dordet
  • Patent number: 7581463
    Abstract: A gear and a method for combining a first gear with a second gear including the steps of moving the first gear relative to the second gear such that a first tooth of the first gear contacts a second tooth of the second gear, pressing the first tooth of the first gear against the second tooth of the second gear such that a resultant force is not directed to a center of at least one of the first gear or the second gear, wherein a torque is created by the resultant force, and rotating at least one of the first gear or the second gear based on the created torque until first teeth of the first gear mesh with second teeth of the second gear.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: September 1, 2009
    Assignee: Xerox Corporation
    Inventors: Jos W. Jacobs, John F. Lombardo, Carl T. Urban
  • Patent number: 7581695
    Abstract: There is described a helicopter having a transmission for transmitting motion from a driving member to a driven member; the transmission has at least a first gear driven by the driving member, and a second gear meshing with the first gear and in turn driving the driven member; the first and second gear have teeth shaped so that the gears mesh with one another at at least two pairs of respective simultaneously meshing teeth; the teeth of at least one of the gears have a profile having an end portion relieved with respect to a starting theoretical involute; and the pattern of the distance between the points of the end portion and the starting involute along an axis of the tooth has at least a first and a second segment sloping with respect to each other.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: September 1, 2009
    Assignee: Agusta S.p.A.
    Inventors: Giuseppe Gasparini, Sergio Sartori, Nihat Yildirim
  • Publication number: 20090165585
    Abstract: The inventive gear drive comprises toothed wheels with teeth of toothed crowns interacting with single- or multi-flow elements. Working profiles of the interacting teeth comprise piecewise and/or pointwise conjugate, convex at a tooth point and concave at a tooth root arc-shaped sections continuously connectable to each other or to involute sections. The interacting toothed crowns are so embodied that a phase gap of the face tooth intermating at a discrete angle from a point, where the interaction of profiles ends at a point, where the interaction of the face profiles of the next tooth pair starts. The drive is so embodied that the face tooth overlap ratio thereof is less than 1. The so improved teeth provide for high level of the contact tightness and absence of axial forces at engagement, increase the structural flexibility of the gear drive teeth in order to improve their qualities.
    Type: Application
    Filed: July 5, 2005
    Publication date: July 2, 2009
    Inventor: German Alexandrovich Zhuravlev
  • Publication number: 20090158876
    Abstract: A group of networked elements for controlling the equipment of a building, when the elements are in a learning mode, can be assembled by a pair of actions. The first action exerted by an installer on one of the elements should be interpreted as an interrogation concerning the state of membership in the group (for example, as included or excluded) of one of the elements of the group. The first action triggers the emission of an information signal regarding the identified element's state. The following, or second, action exerted on the chosen element is interpretable as an order for modifying the state of membership in the group of the chosen element.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 25, 2009
    Inventors: Merle L. Sollars, Donald L. Sollars, Maureen E. Sollars
  • Publication number: 20090151494
    Abstract: A power transmission system and a method for enhancing the efficiency of such systems are provided. The system and method includes a lubricant having a viscosity from about 0.01 centistokes to about 400.00 centistokes, power transmission components with a contact surface finish of less than about 16 microinches, and coating the power transmission components with the lubricant during operation of the system.
    Type: Application
    Filed: December 2, 2005
    Publication date: June 18, 2009
    Inventors: Clark V. Cooper, Joseph J. Sangiovanni, Hongmei Wen, Edward J. Karedes
  • Publication number: 20090139358
    Abstract: In a flat wave gear device in which a flexible externally toothed gear and the rigid internally toothed gear have the same number of teeth, an arcuate tooth profile is imparted to a flexible externally toothed gear, a contact point C between tooth profiles of a flexible externally toothed gear and a D-side rigid internally toothed gear is determined from an arc center A of the arcuate tooth profile of the flexible externally toothed gear and from a momentary center S of relative movement between the gears, and a main part of a tooth profile to be formed in the D-side rigid internally toothed gear is calculated based on the contact point. The tooth profile of the D-side rigid internally toothed gear can be accurately designed; therefore, meshing between the gears can occur with zero backlash, ratcheting torque can be increased, and continuous meshing can occur across a wide range of the movement locus of the tooth profiles of both gears.
    Type: Application
    Filed: November 19, 2008
    Publication date: June 4, 2009
    Applicant: HARMONIC DRIVE SYSTEMS INC.
    Inventor: Shoichi Ishikawa
  • Publication number: 20090139357
    Abstract: In a flat wave gear device, there is determined a rack-approximated movement locus Lc1 of a flexible externally toothed gear with respect to an S-side rigid internally toothed gear accompanying rotation of a wave generator, ?OPT is a minimum value of the radius of curvature of the movement locus Lc1, and is determined from an evolute e of the movement locus Lc1. A convex arc having a radius ? (???OPT) is used in a main part of a tooth profile of the flexible externally toothed gear. A parallel curve c that is set apart from a movement locus Lc2 by the arc radius ? is used on a main part of a tooth profile to be generated on the S-side rigid internally toothed gear. The movement locus Lc2 accounts for the actual number of teeth, and is obtained from a center A of a convex arc of the flexible externally toothed gear being drawn with respect to the rigid internally toothed gear.
    Type: Application
    Filed: November 19, 2008
    Publication date: June 4, 2009
    Applicant: Harmonic Drive Systems Inc.
    Inventor: Shoichi Ishikawa
  • Publication number: 20090120227
    Abstract: The invention is a method of designing a gear, the method including: a first modeling step of modeling one tooth flank (4a) of one gear (W1a) in a CAD system, in such a manner that the one tooth flank (4a) is formed by continuously transitioning a tooth trace consisting of a circular arc (R1), from a tooth root of the gear to a tooth tip thereof; a first designing step of generating a tooth contact curve (R3) as a desired tooth contact position, on the one tooth flank (4a), in the CAD system; a second modeling step of modeling a hypothetical mating tooth flank (51) capable of coming in contact with the one tooth flank (4a) in the CAD system, in such a manner that the hypothetical mating tooth flank (51) is formed by continuously transitioning a hypothetical tooth trace consisting of a circular arc, from a tooth root of a gear to a tooth tip thereof; a second designing step of generating a mating tooth contact curve (R4) on the hypothetical mating tooth flank (51), so as to correspond to the tooth contact curv
    Type: Application
    Filed: July 21, 2006
    Publication date: May 14, 2009
    Inventor: Osamu Kurauchi
  • Patent number: 7526977
    Abstract: A resin-made gearing apparatus that includes a configuration in which only one tooth flank side of each tooth in one of a pair of gears is provided with an overhang section that is disposed on at least one end portion in a tooth width direction, and overhangs diagonally from the one tooth flank side toward the adjacent tooth side; an end portion in a tooth width direction of each tooth in the other gear is provided with a lightening section that is disposed in a tooth flank of each tooth on an end face on the side of the end portion corresponding to the overhang section of the one gear, so that when the opposite teeth of the pair of gears are meshed with each other, the overhang section of the one gear is elastically deformed and also the lightening section of the other gear is elastically deformed, to absorb a backlash.
    Type: Grant
    Filed: January 31, 2006
    Date of Patent: May 5, 2009
    Assignee: Enplas Corporation
    Inventor: Hironori Masui
  • Publication number: 20090107275
    Abstract: There is a gear set. The gear set has a) a first gear having a first surface and b) an intermeshing second gear having a second surface. The first and second surfaces each, independently, have an isotropic arithmetic mean roughness, Ra, of about 3 microinches or less and are lubricated. There is also a method for increasing the contact surface-fatigue life of a gear set.
    Type: Application
    Filed: December 2, 2005
    Publication date: April 30, 2009
    Inventors: Clark V. Cooper, Sonia Tulyani, Edward J. Karedes, Jefferi J. Covington, Alexander Staroselsky, Harsh Vinayak
  • Publication number: 20090090007
    Abstract: A gear is manufactured in a half blanking stage, a punching stage and a separating stage. In the half blanking stage, half blanking is performed for a columnar portion of a metal sheet. A part of an outer circumferential surface of the blank is disconnected from the other portion of the sheet, while the other part of the outer circumferential surface of the blank is connected with the other portion of the sheet. In the punching stage, an inner portion of the blank is punched in a punching direction to form teeth on an inner circumferential surface of the blank. In the separating stage, the blank is separated from the other portion of the sheet as a gear toward a separation direction opposite to the punching direction by disconnecting the other part of the outer circumferential surface of the blank from the other portion of the sheet.
    Type: Application
    Filed: October 2, 2008
    Publication date: April 9, 2009
    Applicant: DENSO CORPORATION
    Inventors: Masahiro Takada, Shigenari Takigiri, Tetsuo Ono
  • Publication number: 20090087563
    Abstract: The invention relates to a method for producing a displacer component that is coated with a diamond coating or layer as well as such a structural component (as a tribologically loaded part). In order to convey or dose a chemically aggressive fluid, a basic structural component (2, 3) is accurately produced in a first dimension (m1) from a chemically not sufficiently resistant but mechanically sufficiently stable first material (A) in a material removing manner. At least the surface sections of said first accurately sized basic component (2, 3) which are actively involved in the displacement are then coated with an at least 1 ?m thick layer (10) of synthetic diamond in a coating process such that a second size (m2) of the structural component is obtained that fits the displacer unit (1). The inventive method makes it possible to produce a chemically resistant, friction reduced structural component for displacing the chemically aggressive fluid.
    Type: Application
    Filed: November 2, 2004
    Publication date: April 2, 2009
    Inventors: Gerald Voegele, Thomas Weisener
  • Publication number: 20090064812
    Abstract: In the toothing system (1) of a gearwheel having a plurality of teeth (2, 3; 19) whose tooth flanks (4, 5, 6; 22) have involute form above a tooth-root region (7, 8, 9; 23) of the tooth flanks (4, 5, 6; 22), the tooth-root region (7, 8, 9; 23) of the tooth flanks (4, 5, 6; 22) that, as viewed in normal section, extends between a root useful point (15, 16, 17; 23) and a root point (F) has elliptical shape, tangentially adjoins the involute region of the tooth flank (4, 5, 6; 22) at the root useful point (15, 16, 17; 24) and tangentially contacts the root circle (FKS) at the root point (F). In its tooth-root region (7, 8, 9; 23), the tooth flank (4, 5, 6; 22), as viewed in normal section, substantially follows a partial section (B) of an ellipse (10, 11, 12; E) whose semiaxes (a, b) have different lengths, one semiaxis (a, b) of the ellipse (10, 11, 12; E) being inclined at an ellipse tilting angle alpha larger than 0° and smaller than 90° relative to a radial (R) through the root point (F).
    Type: Application
    Filed: January 20, 2007
    Publication date: March 12, 2009
    Applicant: SONA BLW PRAZISIONSSCHMIEDE GMBH
    Inventors: Peter Gutmann, Jin Hong Li
  • Publication number: 20090049942
    Abstract: A Cornu's spiral is applied to a tooth profile of a gear. In accordance with the application of the gear, the Cornu's spiral may be modified two-dimensionally by some constant proportion. Since Cornu's spirals have similarity are similar, when a pressure angle is determined, the tooth profile can be standardized by a module, so that it is highly versatile. By replacing the tip of a tooth and the bottom of a tooth by another curve, such as an arc, the range of application can be increased. Since working is always by flank contact between a protrusion and a recess, contact surface stress is low. In addition, the radius of curvature of a dedendum is large. Therefore, tooth bending stress is low, and fatigue strength is high. Even if the number of teeth is small, an undercut is not produced. Even if there is no backlash, a smooth working is achieved, so that the tooth profile is suitable for devices requiring precise alignment.
    Type: Application
    Filed: April 6, 2006
    Publication date: February 26, 2009
    Inventors: Tsutomu Miyaoku, Jiro Kanehiro, Hidekazu Sasaki
  • Publication number: 20080282827
    Abstract: This invention relates to a kind of gear pair for power transmission in speed increaser or reducer and its tooth profile forming method, the tooth profiles of driving gear (1) and driven gear (2) are separately designed from the reference points, the upper tooth profiles (15, 25) are composed of conjugate curves, while the lower tooth profiles (14, 24) are composed of smooth convex analytic curves. The reference point (22) of the driven gear (2) situates near the middle of the working depth, while the reference point (12) on the tooth profile (11) of the driving gear (1) and the reference point (22) on the driven gear tooth flank (21) are a pair of conjugate point This invention can greatly enhance the load capacity of the gear pair.
    Type: Application
    Filed: October 27, 2006
    Publication date: November 20, 2008
    Inventors: Hong Jiang, Xiaochun Wang
  • Patent number: 7437967
    Abstract: A gear having window holes, and method and apparatus for mafufacturing the same in which by depressing partially one end surface of a primary formed article, a plurality of concaves for the window holes is formed at the one end surface in an axial direction of the primary formed articles, a plurality of projections are extruded from the other end surface thereof and tooth forms preformed at an outer peripheral wall of the primary formed article is thrown out in radial direction thereof, and the gear is formed by cutting the plurality of projections extruded from the other end surface thereof.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: October 21, 2008
    Assignee: O-Oka Corporation
    Inventor: Tomoyoshi Okada
  • Publication number: 20080236320
    Abstract: Noise can be effectively reduced without rotative power transmission accuracy being compromised. In a tooth 2 of a resin gear 1, a tooth face that is a predetermined area from a tooth crest 8 towards a tooth root 10 side serves as a tooth profile modification area 11. A tooth surface excluding the tooth profile modification area 11 serves as an involute profile area 12. The tooth profile modification area 11 includes a linear standard profile portion 14 formed by an involute curved line from the tooth crest 8 of the tooth towards the tooth root 10 side and a profile modification portion 16 in which a tooth thickness gradually and smoothly decreases from the standard profile portion 14 along a tooth width direction and the tooth thickness gradually and smoothly decreases from a tooth root end side 15 towards the tooth crest 8. In the tooth profile modification area 11, a contacting section becomes elastically deformed as a result of the resin gear coming into contact with a meshing mating gear.
    Type: Application
    Filed: March 19, 2008
    Publication date: October 2, 2008
    Inventor: Toru Takumori
  • Patent number: 7415907
    Abstract: A gear train for an ink jet printer includes an output gear of a motor, a first idle gear meshing with the output gear, a second idle gear rotatable with the first idle gear, and a driven gear which is mounted on a roller shaft so as to be rotatable therewith and which meshes with the second idle gear. A resin double helical gear is used as each of the output gear and the first idle gear, and a spur gear is used as each of the second idle gear and the driven gear. The resin double helical gear may have a meshing relief portion formed by cutting a chevron-shaped top portion in a central portion in face width directions, which is arranged in a butt portion between a first die and a second die, from a tooth crest to a portion near a bottom lane so as to decrease a tooth thickness.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: August 26, 2008
    Assignee: Enplas Corporation
    Inventor: Toru Hagihara
  • Patent number: 7407373
    Abstract: An inner motor is structured to increase the discharge rate of an internal gear pump by making it possible to freely adjust the eccentricity e between the inner and outer rotors. Each tooth of the inner rotor includes a tooth bottom defined by hypocycloidal curves, an engaging portion to be brought into engagement with the outer rotor and defined by involute curves, and a tooth top defined by a predetermined curve such as a part of a circle or an oval or an epicycloidal curve.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: August 5, 2008
    Assignee: Sumitomo Electric Sintered Alloy, Ltd.
    Inventors: Daisuke Ogata, Naoki Inui, Shinya Arinaga
  • Patent number: 7377355
    Abstract: In a motor-driven power steering apparatus for a vehicle in which a worm wheel of a worm gear type speed reduction mechanism is fixed to a pinion shaft of a rack and pinion mechanism, a direction of a torsion angle ? of a helical pinion provided in the pinion shaft is set to be opposite to a direction of a tooth lead angle ? of the worm wheel.
    Type: Grant
    Filed: December 7, 2004
    Date of Patent: May 27, 2008
    Assignee: Showa Corporation
    Inventors: Yutaka Sasaki, Katsuyuki Yoshida
  • Publication number: 20080115610
    Abstract: A tooth profile for a tooth of a high contact ratio spur gear, the tooth having an active profile, a root, and a tip, the active profile having a start adjacent to the root and having an end adjacent to the tip, includes a base tooth profile extending from the start of the active profile to an operating pitch area of the high contact ratio spur gear; and a modified base tooth profile, the modified base tooth profile being the base tooth profile modified by a profile relief curve, the modified base tooth profile extending from the operating pitch area to the end of the active profile, thereby yielding a long profile modification.
    Type: Application
    Filed: November 21, 2006
    Publication date: May 22, 2008
    Inventors: Roman Cisek, Jian Lin, Robert James White
  • Publication number: 20080022800
    Abstract: A gear pair includes a small-diameter conical involute gear having a conical angle, and a large-diameter conical involute gear having a conical angle. The small-diameter conical involute gear and the large-diameter conical involute gear are constituted by an aggregate of imaginary cylindrical gears.
    Type: Application
    Filed: July 31, 2007
    Publication date: January 31, 2008
    Applicant: JTEKT Corporation
    Inventor: Tsune KOBAYASHI
  • Patent number: 7267024
    Abstract: An idler gear having a part worked by cutting is formed such that a chamfer part is formed at least on a portion between a tooth shape and chamfers are formed on the tooth shape by a forging process on an outer peripheral surface and an end part thereof in an axial direction by cutting.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: September 11, 2007
    Assignee: O-OKA Corporation
    Inventor: Makoto Kimura
  • Patent number: 7191521
    Abstract: The present invention provides for bevel gears having a localized and stable bearing contact. The localization of bearing contact is achieved by substitution of flat tooth surfaces with parabolic tooth surfaces. This is accomplished by either modifying line-contact directly or by using a generating parabolic cylinder during generation of the tooth surfaces. The actual contact area is spread over an ellipse centered around an instantaneous theoretical point of contact at the apex of the parabolic tooth surface. This localized bearing contact reduces the shift of the bearing due to assembly and manufacturing errors, thereby providing a more durable and quieter gear. Furthermore, the geometry of the gear enables creation of dies from which the gear may be forged. Transmission errors are modeled using a pre-designed parabolic function that coincides with the parabolic tooth surface design of the present invention.
    Type: Grant
    Filed: February 7, 2003
    Date of Patent: March 20, 2007
    Assignee: American Axle & Manufacturing, Inc.
    Inventors: Faydor L. Litvin, Xiangshun Zhao, John Sofia, Theresa Barrett
  • Patent number: 7137312
    Abstract: A method is disclosed for the manufacture of gear wheels having two axially adjacent gears (4,6) thereon. A blank is prepared with the two gears crudely formed thereon by compressing and sintering a shaped mass of substantially metal powder. The blank is then mounted for rotation about a first axis, and the gears are roll-formed on the blank by rotating the blank in meshing engagement with respective dies (10,12) mounted for rotation about second and third axes substantially parallel to the first axis.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: November 21, 2006
    Assignee: FormFlo Limited
    Inventor: Christopher John Cole
  • Patent number: 7077026
    Abstract: A gear system which includes a pinion and mating-gear forming a gear pair with a predetermined gear ratio (mG), center distance (C), face-width (Fw), and limiting stresses. The pinion has a pinion tooth number (N1) and a first plurality of teeth, each tooth having a first-tooth profile. The mating gear has a mating-gear tooth number (N2) satisfying the expression N2=mG·N1 and a second plurality of teeth, each tooth having a second-tooth profile. The relative curvature of the first-tooth profile and the second-tooth profile is given by the expression kc·Fc, where Fc is a relative reference curvature function given by the expression Fc=(N1+N2)2/(N1·N2·C), and kc is a relative curvature multiplier which is a function of the gear ratio (mG), the center distance (C), the face-width (Fw), and the limiting stresses.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: July 18, 2006
    Assignee: Genesis Partners, L.P.
    Inventor: John R. Colbourne
  • Patent number: 7069805
    Abstract: A driving force transmission device includes a rim having a toothed outer periphery, with bottom lands being formed between respectively adjacent teeth and top lands being formed at teeth crests. Outer ribs are disposed at positions on an inner peripheral surface of the rim corresponding to the bottom lands, whereby there is neither variance in angle speed nor uneven rotation of a member driven by the transmission device. Moreover, the outer ribs are radially offset from inner ribs, whereby tensile forces generated between the outer and inner ribs and caused by material shrinkage cancel each other out and defective molding of teeth crests can be minimized. Accordingly, the radius of an imaginary circle formed by joining the top lands is uniform in a circumferential direction.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: July 4, 2006
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tetsuya Ishizuka, Hiromichi Nakayama
  • Patent number: 7024725
    Abstract: This invention relates to an overhead door closer with slide arm assembly having a toothed pinion that is eccentrically supported and presents a circular rolling curve, which pinion meshes with a toothed rack arranged at a piston. The invention concentrates on a particular embodiment of the rolling curve and of the teeth of the toothed rack in adaptation to a toothing of the pinion. Furthermore, the invention concentrates on an improved embodiment of the delayed closing operation in order to achieve an optimized movement pattern of the piston within the housing of the overhead door closer with slide arm assembly.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: April 11, 2006
    Assignee: Dorma GmbH + Co. KG
    Inventor: Jürgen Homberg
  • Patent number: 6964210
    Abstract: A gear and method for producing the gear. The gear has a gear tooth profile conjugate to a gear basic-cutter tooth-profile having an addendum with a convex portion having an addendum point proximal to a pitch line and a dedendum with a concave portion having a dedendum point proximal to the pitch line. The convex portion is complementary with a corresponding portion of a mating-gear basic-cutter tooth-profile dedendum. The concave portion is complementary with a corresponding portion of the mating-gear basic-cutter tooth-profile addendum. A transition zone between the addendum point and the dedendum point has a predetermined width. The gear basic-cutter tooth-profile has a predetermined half pitch relief at the pitch line and continuity of profile and continuity of slope at the addendum point.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: November 15, 2005
    Assignee: Genesis Partners, L.P.
    Inventor: John R. Colbourne
  • Patent number: 6918181
    Abstract: A method for improving acoustic and vibrational properties of gears includes determining the transmission errors of intermeshing gears due to stiffness variations in the gear teeth, performing Gear Tooth Topological (GTT) modifications to compensate for the errors, and isotropically processing the gears to produce an ultra-smooth surface finish. Additional errors from isotropic processing, machining, loading, thermal effects and/or load sharing may be summed with the errors from the stiffness variations and used for the GTT modifications. The teachings of the present invention may reduce noise by as much as 13 to 15 dB.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: July 19, 2005
    Assignee: Sikorsky Aircraft Corporation
    Inventors: Harsh Vinayak, Bruce D. Hansen, Edward J. Karedes, Clark V. Cooper, Lawrence M. Zunski
  • Patent number: 6896501
    Abstract: Present invention provides a single screw compressor from which only a small amount of gas to be compressed leaks and which can be manufactured at low costs. There are provided a screw rotor 1 having six grooves 2, 2, . . . and a gate rotor 4 having 12 teeth 5, 5, . . . which are installed in a casing. Since six, which is the number of the grooves of the screw rotor 2, and twelve, which is the number of the teeth 5 of the gate rotor, have a common divisor, only predetermined teeth 6 are engaged with a groove 2. Therefore, engagement combinations of the grooves 2 and the teeth 5 are divided into six groups. In each of these groups, dimension accuracy is controlled so that the grooves 2 and the teeth 5 engaged each other have appropriate clearances. Since manufacture is easier when dimension accuracy is controlled within each group than when dimension accuracy of all grooves 2 and teeth 5 is controlled at one time as in a conventional case, this single screw compressor becomes inexpensive.
    Type: Grant
    Filed: December 7, 2001
    Date of Patent: May 24, 2005
    Assignee: Daikin Industries, Ltd.
    Inventors: Hiromichi Ueno, Kaname Ohtsuka
  • Patent number: 6893238
    Abstract: A displacement-type ring gear machine includes a casing including a gear chamber comprising a supply port and a discharge port, an internal gear accommodated in the gear chamber and comprising an external toothing, and an external gear eccentric to the internal gear and comprising an internal toothing meshing with the external toothing so as to form expanding and contracting fluid cells which direct the working fluid from the supply port to the discharge port. The meshing toothings comprise a radial clearance and a tangential clearance which is smaller than the radial clearance. The tips or roots of at least one of the two toothings comprise a profile derived from a cycloid.
    Type: Grant
    Filed: March 3, 2003
    Date of Patent: May 17, 2005
    Inventors: Siegfried A. Eisenmann, Hermann Härle
  • Patent number: 6890164
    Abstract: A noise-reduced internal gear pump incorporating an inner rotor having an addendum formed by a smooth curve and a dedendum formed by a hypocycloid. The tooth profile of the outer rotor is determined by the following steps. The center Oi of an inner rotor 1 is revolved around the center Oo of the outer rotor so as to form a circle S having a diameter of 2e+t, where “e” is the amount of eccentricity between the inner and outer rotors and “t” is the maximum value of the interrotor clearance between the outer rotor and the inner rotor pressed against it. The inner rotor 1 is rotated on its axis 1/n times while its center Oi makes one revolution in the circular orbit S, where “n” is the number of teeth of the inner rotor. The envelope of the group of the tooth profile-curves of the inner rotor formed by its revolution is used as the tooth profile of the outer rotor.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: May 10, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Daisuke Ogata, Naoki Inui, Shinya Arinaga, Harumitsu Sasaki
  • Patent number: 6883397
    Abstract: A gear made of a resin includes a substantially cylindrical rim having a plurality of teeth formed around an outer periphery thereof, a boss formed about a rotational center of the rim, and a web connecting the boss and the rim to each other. At least one groove is defined along outer surface of each tooth to divide the tooth in a widthwise direction of the tooth. As a result, a portion of the gear, in which the grooves are defined, is deformed in a reduced amount, leading to a reduced amount of deformation such as a warpage or sink in the entire gear, thereby providing an enhancement in tooth flank accuracy. Since the grooves are defined along the outer surfaces of the teeth, a lubricant such as grease can be supplied effectively to tooth flanks by previously applying the lubricant in the grooves.
    Type: Grant
    Filed: July 5, 2001
    Date of Patent: April 26, 2005
    Assignee: Enplas Corporation
    Inventor: Genichi Kimizuka
  • Patent number: 6848558
    Abstract: A sintered selector or sliding sleeve, or gear shift sleeve, has internal claw toothing. The individual teeth are delimited on their ends with secondary surfaces having ends that extend radially inward and outward from the root circle of the inner tooth surfaces. The novel geometry of the secondary surfaces extending radially outward from the root circle provide advantages in the manufacture of such selector sleeves by powder metallurgy, compared with those having prior art tooth geometries.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: February 1, 2005
    Assignee: Sinterstahl GmbH
    Inventors: Günter Rau, Lorenz Sigl, Heinrich Wiedemann
  • Patent number: 6837123
    Abstract: Several embodiments of various non-involute gear tooth profiles incorporate relief areas formed across the area of the tooth face generally symmetrically to each side of the pitch circle of the gear. The relief area serves to preclude contact across the areas of meshing or mating gear teeth where convex-to-convex contact would otherwise occur, thus precluding high pressure contact between the two gear teeth at the area of the relief. The remainder of the contact of such non-involute gear tooth profiles provides conformal contact, i. e., convex-to-concave mating faces with correspondingly low pressures developed between the tooth portions. The present invention enables a given gear set to absorb considerably greater torque and force than would otherwise be they case, or alternatively allows gear sets to be made considerably smaller and lighter for a given torque transmission, than would otherwise be the case.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: January 4, 2005
    Inventor: Richard M. Hawkins