Making A Noncircular Gear, Worm, Rotor, Or A Planar-faced Gear Patents (Class 409/48)
  • Patent number: 11808337
    Abstract: One aspect of the present invention provides a method for manufacturing a strain wave gear device. The method includes steps of measuring a between pin diameter of an internal gear, measuring an over pin diameter of an external gear, where the external gear is to be placed radially inside the internal gear, configured to mesh with the internal gear, and flexible, measuring a dimension of a bearing, where the bearing is to be placed radially inside the external gear, and flexible, and machining an elliptical cam, where the elliptical cam is to be placed radially inside the bearing, and configured to flex the external gear in a non-circular manner. The elliptical cam is machined based on the measured dimensions of the internal gear, external gear and bearing such that the internal and external gears mesh with each other at a constant position.
    Type: Grant
    Filed: March 1, 2022
    Date of Patent: November 7, 2023
    Assignee: NABTESCO CORPORATION
    Inventors: Masashi Imai, Yuichi Asakawa
  • Patent number: 11292515
    Abstract: A work vehicle includes a chassis defining a longitudinal axis, a prime mover configured to move the chassis in the direction of the longitudinal axis, and a steering assembly configured to pivot a wheel relative to the chassis. The steering assembly includes a knuckle coupled to the wheel, a tie rod coupled to the knuckle and having a ball portion, a steering cylinder, and a joint assembly. The steering cylinder is slidably coupled to the chassis and configured to translate relative to the chassis along a cylinder axis perpendicular to the longitudinal axis. The steering cylinder includes a connection portion having an inner circumferential surface that partially defines a bearing pocket. The joint assembly couples the ball portion to the connection portion and includes a bearing race that is received into the bearing pocket in direct contact with the inner circumferential surface. The bearing race receives the ball portion.
    Type: Grant
    Filed: March 27, 2020
    Date of Patent: April 5, 2022
    Assignee: DEERE & COMPANY
    Inventor: Curtis P. Thoreson
  • Publication number: 20130089386
    Abstract: A variable-tooth-thickness worm-type tool comprises a main body and a spiral blade distributed on the main body and featuring variable tooth thickness. The main body and the spiral blade are respectively described with a rack cutter coordinate system and a tool coordinate system. The vector parameters based on the rack cutter coordinate system are transformed into vector parameters based on the tool coordinate system so as to simulate the main body with a rack cutter and develop the spiral blade to have variable tooth thickness. Thus, when a gear blank is tooled, the distance between the centers of the tool holder and the workpiece holder can be set as a constant, and the feed in the radial degree-of-freedom can be neglected, with twists of tooth flanks being inhibited.
    Type: Application
    Filed: March 20, 2012
    Publication date: April 11, 2013
    Inventors: Zhang-Hua FONG, Ruei-Hung Hsu, Wei-Hsiang Wang
  • Publication number: 20120057944
    Abstract: A gear machining apparatus includes a skiving mechanism positioning a work to be machined and a pinion type cutter on axes skewing from each other, the skiving mechanism rotating the work at a predetermined position and feeding the cutter while rotating in a direction of a tooth trace of a gear to be formed at the work synchronously to the rotation of the work for producing the gear from the work. The cutter includes a tooth surface which is formed with an involute region having an involute curve in an area including a pitch circle in a tooth depth direction, an addendum region continuously formed from the involute region to an addendum, and a dedendum region continuously formed from the involute region to a dedendum the addendum region and the dedendum region being shaped in a configuration different from the involute region.
    Type: Application
    Filed: August 26, 2011
    Publication date: March 8, 2012
    Applicant: AISIN SEIKI KABUSHIKI KAISHA
    Inventor: Eiri NAGATA
  • Patent number: 8118522
    Abstract: A working apparatus, provided with a base stage, work hold and rotation device for holding and rotating a work, working device movable toward and away from the work via slider mechanism and having a working tool, press structure for pressing the working tool toward the work via the working device, and trace device pressed toward the work together with the working tool by the press structure and in contact with the work and moving the working device as a whole in forward and rearward directions according to outer shape of the work. By pressing of the pressing structure, the working tool deburrs and chamfers under control of working volume by the trace device. The work hold and rotation device has work rotation axis angle adjustment mechanism, for adjusting angle of rotation axis of the work by holding the work. The working apparatus can precisely deburr and chamfer complicated shape of work such as worm gear.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: February 21, 2012
    Assignee: Senjo Seiki Co., Ltd.
    Inventor: Masaharu Nakajima
  • Publication number: 20080273935
    Abstract: A method for cutting worm and worm wheel in a worm-gear reduction unit (1) with circulation of bearing balls, comprising the steps of: (a) obtaining races (30) for the bearing balls (4) onto the worm wheel (3); and (b) obtaining races (20) for the bearing balls (4) onto the worm (2), wherein step (b) provides the cutting of the races (20) according to a cutting profile substantially corresponding to the envelope of the subsequent positions assumed by the bearing balls within the worm wheel races being formed.
    Type: Application
    Filed: March 14, 2005
    Publication date: November 6, 2008
    Inventors: Pietro Salvini, Domenico Serpella, Francesco Vivio, Vincenzo Vullo
  • Patent number: 7226255
    Abstract: The present invention provides a five-simultaneously-working axis computerized numerical controlling system tooth cutting machine tool for toroidal worms, comprising two parts a body of the machine tool and a controlling cabinet. The body comprises a bed, a spindle box with a spindle, a longitudinal sliding table, a traverse slider, a vertical guideway mounted on the slider and a tailstock, a cutter rest that supports a rotating cutter head is mounted on the vertical guideway. The spindle rotates about A-axis thereof, the table longitudinally slides along Y-axis relative to the bed, the cutter head rotates about B-axis thereof and transversely shifts X-axis as well as the cutter head makes up or down shift along Z-axis of the vertical guideway.
    Type: Grant
    Filed: November 9, 2004
    Date of Patent: June 5, 2007
    Assignees: Tianjin Teda Development Centre for Worm Gear Transmission, Tsubaki Emerson Gear (Tianjin) Co., Ltd.
    Inventors: Yaxiong Zhang, Lin Qi
  • Patent number: 7044691
    Abstract: A forming method for milling teeth of variable tooth worms (VTW) with the following features: on a multi-axis simultaneously-working CNC machine-tool a moving coordinate system {?1(?1)[O1;{right arrow over (i)}1(?1),{right arrow over (j)}1(?1),{right arrow over (k)}1 (?1)]} is correlated to the worm blank of the VTW worms, whereon the worm blank of the VTW worms rotates around {right arrow over (k)}1(?1)-axis at angular speed |{right arrow over (?)}1|; another moving coordinate system {?2(?2)[O2; {right arrow over (i)}2(?2), {right arrow over (j)}2(?2), {right arrow over (k)}2(?2)]} is correlated to the milling cutter, whereon the milling-cutter rotates around {right arrow over (k)}2(?2)-axis at angular speed |{right arrow over (?)}2|, |{right arrow over (?)}1|/|{right arrow over (?)}2|=i12 and i12 is a constant; the feed motion of the milling cutter comprises the radial shift along {right arrow over (i)}2(o2)-axis and the peripheral shift around {right arrow over (k)}2(?2)-axis; the equations of the cutting
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: May 16, 2006
    Assignee: Tsubaki Emerson Gear (Tianjin) Co., Ltd.
    Inventors: Yaxiong Zhang, Lin Qi
  • Patent number: 6916140
    Abstract: Enveloping worm threads with less than one revolution have on one side concave surface and on another side convex surface. This makes generation of concave and convex enveloping worm surfaces simultaneously and makes modification of surfaces by individual machining of each surface. Proposed method uses cutting edges that have rotation radius according with radius of curvature of machining surface. Another variation simultaneously cuts several threads, where enveloping worm blank has rotation around its own axis of rotation and relative motion to helical cutter around tooling axis. This reduces production cost and makes manufacturing easily.
    Type: Grant
    Filed: September 24, 2003
    Date of Patent: July 12, 2005
    Inventor: Yakov Fleytman
  • Patent number: 6764257
    Abstract: A milling tool includes a milling body and a plurality of cutting inserts. The milling body has fastening devices to hold the cutting inserts in a plurality of respective insert pockets each having at least one base surface. Each of the cutting inserts has at least one cutting edge. The tool has a rotational axis and a rotational direction, as well as a feed direction and an end surface. The milling tool is provided to cut a work piece substantially in an axial direction of the tool, which is substantially perpendicular to the feed direction.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: July 20, 2004
    Assignee: Seco Tools AB
    Inventor: Jorma Koskinen
  • Publication number: 20040033114
    Abstract: A forming method for milling teeth of variable tooth worms (VTW) with the following features: on a multi-axis simultaneously-working CNC machine-tool a moving coordinate system {&sgr;1(&phgr;1)[O1;{right arrow over (i)}1 (&phgr;1),{right arrow over (j)}1 (&phgr;1),{right arrow over (k)}1 (&phgr;1)]} is correlated to the worm blank of the VTW worms, whereon the worm blank of the VTW worms rotates around {right arrow over (k)}1(&phgr;1)-axis at angular speed |{right arrow over (&ohgr;)}1|; another moving coordinate system {&sgr;2(&phgr;2)[O2; {right arrow over (i)}2 (&phgr;2), {right arrow over (j)}2(&phgr;2), {right arrow over (k)}2(&phgr;2)]} is correlated to the milling cutter, whereon the milling-cutter rotates around {right arrow over (k)}2(&phgr;2)-axis at angular speed |{right arrow over (&ohgr;)}2|, |{right arrow over (&ohgr;)}1|/|{right arrow over (&ohgr;)}2|=i12 and i12 is a constant; the feed motion
    Type: Application
    Filed: May 19, 2003
    Publication date: February 19, 2004
    Inventors: Yaxiong Zhang, Lin Qi
  • Publication number: 20020067966
    Abstract: A method of forming milled tooth of variable tooth worm (VTW),comprising: coupling a workpiece of worm with a coordinate system {&sgr;1(&phgr;1)[O1; {overscore (i)}1(&phgr;1), {overscore (j)}1(&phgr;1), {overscore (k)}1(&phgr;1)]} on the CNC multi-axes simultaneously coupled machine tool, in which the workpiece of worm is rotated with the angular speed &ohgr;1 around the axis of {overscore (k)}1(&phgr;1); coupling a milling-cutter with another coordinate system {&sgr;2(&phgr;2)[O2; {overscore (i)}2(&phgr;2), {overscore (j)}2(&phgr;2), {overscore (k)}2(&phgr;2)]} on the CNC multi-axes simultaneously coupled machine tool, in which the milling-cutter is rotated with angular speed &ohgr;2 around the axis of {overscore (k)}2(&phgr;2), and &ohgr;1/&ohgr;2=i and i is constant; feeding the milling-cutter to move along {overscore (i)}2(O2) axis in the radial direction and simultaneously rotate around {overscore (k)}2(&phgr;2) in the circumference direction, the coordinate
    Type: Application
    Filed: October 17, 2001
    Publication date: June 6, 2002
    Inventors: Yaxiong Zhang, Lin Qi
  • Patent number: 5720584
    Abstract: In the production of a crown wheel which can mesh with a cylindrical pinion if the axes of rotation of the crown wheel and the pinion are not parallel, the workpiece from which the crown wheel is produced and a generating tool rotate at a ratio in the speed of rotation which corresponds to the proportion of the number of passes of the tool and the number of teeth of the crown wheel to be produced, and the tool is brought into engagement with the workpiece and is moved in such a way along the workpiece in a direction parallel to the axis of rotation of the cylindrical pinion that the tool works the tooth flanks of the crown wheel to be produced. When the center point of the tool is moved in a direction parallel to the axis of rotation of the cylindrical pinion which can mesh with the workpiece, and the teeth of which form an angle .beta.
    Type: Grant
    Filed: November 8, 1995
    Date of Patent: February 24, 1998
    Assignee: Crown Gear B.V.
    Inventor: Anne Lourens Sijtstra
  • Patent number: 5718544
    Abstract: A base member such as an elevation pipe of a photographic tripod is severed and rack teeth are formed thereon in a single operation while the base member remains clamped in a V-block. The first rack tooth on each side of the location where the base member is severed includes half of a trough portion between adjacent rack teeth. Additional trough portions forming the remainder of the teeth are formed, either in the same severing and shaping operation, or in a later shaping operation. The formation of the inner half trough portions ensures that, when the two severed ends of the base member are brought together, a smooth transition will exist between the two rack portions. In addition, since the two severed ends always include half troughs immediately adjacent thereto, weaknesses and chipping resulting from the presence of partial rack teeth in these locations is avoided.
    Type: Grant
    Filed: July 2, 1996
    Date of Patent: February 17, 1998
    Assignee: Nihon Velbon Seiki Kogyo Kabushiki Kaisha
    Inventor: Koichiro Nakatani
  • Patent number: 5647703
    Abstract: There is disclosed a globoid worm gear generating method in which the surface of a globoid worm generating tool is defined as the tooth surface of an intermediate gear by an inverted conical surface whose semivertical angle .gamma. is 90.degree.<.gamma.<180.degree., a relational movement similar to that of a globoid worm wheel is given to the tool so as to generate a globoid worm, and the worm wheel is generated by a wheel generating tool having a contour wholly or partially similar to that of the globoid worm, or in which the surfaces of a globoid worm generating tool are defined wholly or partially by two inverted conical surfaces whose semivertical angles .gamma. are 90.degree.<.gamma.<180.degree., and the major axes as well as bottoms of the two inverted conical surfaces are coincident with each other so that both tooth surfaces of a worm may be simultaneously generated. By this method of the invention, the globoid worm gears can be generated within a short period of time.
    Type: Grant
    Filed: July 10, 1995
    Date of Patent: July 15, 1997
    Assignee: Sumitomo Heavy Industries, Ltd.
    Inventor: Akiyo Horiuchi
  • Patent number: 5598618
    Abstract: A method and apparatus for making a globoid screw for use as a mainrotor in a compressor or expander wherein a cylindrical rotor body is mounted for rotation about the longitudinal axis thereof, a cutter having a plurality of teeth at spaced locations around a circumference disposed in a plane and having an axis of rotation disposed perpendicular to that plane is mounted for rotation about its axis and is disposed so that the plane thereof is parallel to the rotor body longitudinal axis and so that the cutter rotational axis is perpendicular to the rotor longitudinal axis, and the rotor body and the cutter are rotated at synchronized speeds.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: February 4, 1997
    Inventors: Giovanni Aquino, Ewan Choroszylow
  • Patent number: 5279174
    Abstract: A worm speed reducer consisting of a worm made of a relatively hard material such as cast iron or steel and a worm wheel made of a relatively hard material such as cast iron. A material strength is set so that an amount of wear of the worm becomes larger than that of the worm wheel. A tooth surface of the worm wheel is formed with a network irregularity extending in both a direction of a cutting scratch due to cutting and a direction intersecting the direction of the cutting scratch, and also formed with a chemical conversion coating having a thickness smaller than a height of the irregularity. A tooth surface of the worm is formed with a network irregularity extending in both a direction of a cutting scratch due to cutting (or a grinding scratch due to grinding) and a direction intersecting the direction of the cutting scratch (or the grinding scratch) of the worm, and also formed with a chemical conversion coating having a thickness smaller than a height of the irregularity of the worm.
    Type: Grant
    Filed: May 19, 1992
    Date of Patent: January 18, 1994
    Assignee: Sumitomo Heavy Industries, Ltd.
    Inventor: Kiyoji Minegishi
  • Patent number: 5084965
    Abstract: Method and device for grooving an hourglass screw wherein a tool shaft having an axis transverse to the screw blank has a tool movable selectively stepwise relative to the shaft when the tool is not engaged with the screw blank and locking means fix the tool when engaged with the screw blank for the grooving operation.
    Type: Grant
    Filed: April 11, 1991
    Date of Patent: February 4, 1992
    Inventor: Bernard Zimmern
  • Patent number: 5031292
    Abstract: A method and apparatus for making a globoid screw for use as a mainrotor in a compressor or expander wherein a cylindrical rotor body is mounted for rotation about the longitudinal axis thereof, a cutter having a pluality of teeth at spaced locations around a circumference disposed in a plane and having an axis of rotation disposed perpendicular to that plane is mounted for rotation about its axis and is disposed so that the plane thereof is parallel to the rotor body longitudinal axis and so that the cutter rotational axis is perpendicular to the rotor longitudinal axis, and the rotor body and the cutter are rotated at synchronized speeds.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: July 16, 1991
    Inventors: Giovanni Aquino, Ewan Choroszylow
  • Patent number: 5018403
    Abstract: The present invention relates to a speed reduction apparatus for globoid worm gears. The speed reduction ratio of the engaged worm globoid worm gear and worm wheel is defined as the ratio of the rate of rotation of the globoid worm gear about its axis to the rate of rotation of the worm wheel about its axis. The structure of the present invention speed reduction apparatus is defined by the distance between the axes of rotation of the worm wheel and globoid worm gear and the spacial and speed relationships between the globoid worm gear and the surfaces of the cutting tool employed to generate the worm gear.
    Type: Grant
    Filed: June 20, 1990
    Date of Patent: May 28, 1991
    Assignee: Nippon Gear Co., Ltd.
    Inventors: Shiro Umezono, Minoru Maki
  • Patent number: 4588336
    Abstract: A rack and pinion gear having helical teeth. A conical hob is employed for cutting recessed rack teeth in the work piece by continuously engaging the hob and work piece as the work piece moves longitudinally beneath (or with respect to) the rotating hob. To mate with the helical teeth in the rack, a helical gear having rounded or arcuate teeth is provided.
    Type: Grant
    Filed: April 19, 1985
    Date of Patent: May 13, 1986
    Inventor: Bernard J. Navarro
  • Patent number: 4588337
    Abstract: A method and apparatus are disclosed for machining hourglass screw threads on an enveloping-type worm screw by engaging at least one angularly positioned cutter with a screw blank having an hourglass shape. The screw blank is rotated about its central longitudinal axis at the same time that each angularly positioned cutter is pivoted through the screw blank at a rate which is less than the rate of rotation of the screw blank.
    Type: Grant
    Filed: March 13, 1984
    Date of Patent: May 13, 1986
    Assignee: Maxaxam Corporation
    Inventor: George E. Brackett
  • Patent number: 4521141
    Abstract: This invention pertains to a rack and pinion type steering gear for an automobile and a method for cutting rack teeth in the gear. The gear comprises a housing, a pinion rotatably supported within the housing and operatively connected to a steering wheel and a rack bar supported within the housing for slidable movement in the axial direction and rotation and provided with rack teeth in engagement with the pinion. The rack teeth are formed on the rack and along a varying pitch line so that the axial movement amount of the rack varies as the pinion rotates.
    Type: Grant
    Filed: January 19, 1983
    Date of Patent: June 4, 1985
    Assignee: Tokai TRW & Co., Ltd.
    Inventor: Michio Abe
  • Patent number: 4222691
    Abstract: A tool having only an end cutting-edge carries out a first movement of penetration into a screw blank so as to produce a groove having flanks substantially parallel to the pinion axis. The tool-holder is angularly displaced with respect to the spindle which carries the screw blank. A second movement of tool penetration takes place while the relative displacement is progressively reduced in order to obtain an inclined flank which produces a V-shaped profile. The screw is intended to form part of a compression and expansion machine and to cooperate with at least one pinion having V-form teeth.
    Type: Grant
    Filed: April 18, 1978
    Date of Patent: September 16, 1980
    Assignee: Uniscrew Limited
    Inventor: Bernard Zimmern