Particular Mathematical Equation Patents (Class 475/904)
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Patent number: 12078206Abstract: A pressure plate bearing device assembled by quick connection includes a bearing and a pressure plate. The pressure plate includes a sleeving hole which sleeves outside an outer race of the bearing, a limiting groove provided in a position where the outer race of the bearing is nested in the sleeving hole in a matching manner, and a steel ball arranged in the limiting groove. Based on the limiting match between the steel ball and the sleeving hole and that between the steel ball and the outer race of the bearing, at least the axial limit between the bearing and the pressure plate is at least fulfilled. The outer race of the bearing or the pressure plate is provided with a mounting channel that is in communication with the limiting groove. The pressure plate bearing device assembled by the quick connection is more easily assembled and reliably connected.Type: GrantFiled: September 16, 2021Date of Patent: September 3, 2024Assignee: C&U COMPANY LIMITED.Inventors: Jialiang Xu, Xuefeng Bai, Shuwu Zhang
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Patent number: 12072013Abstract: A differential gear device for a vehicle including a housing, a pinion shaft provided inside the housing, a pinion gear respectively mounted on both ends of the pinion shaft, and a pair of side gears respectively disposed on both sides of a width direction of a vehicle and engaged to the pinion gear. A disconnector actuator system is coupled to one side gear and a drive shaft is coupled to the other side gear among the pair of the side gears. The differential gear device for the vehicle includes a noise reduction unit provided between the cover to which the drive shaft is coupled and the other side gear to prevent a whine noise from being generated between the pinion gear and the other side gear during the operation of the disconnector actuator system.Type: GrantFiled: March 18, 2022Date of Patent: August 27, 2024Assignees: HYUNDAI MOTOR COMPANY, KIA CORPORATIONInventors: Hyun Ku Lee, Moosuk Kim, Kihyun Lee, Jae Oh Kwak, Geum Muk Chae, Jung-Hwan Moon
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Patent number: 11890930Abstract: Systems are provided for a differential of an electric powertrain. In one example, a system includes a portal axle coupled to only one side of a differential, the portal axle comprising a first axle and a second axle coaxial with one another.Type: GrantFiled: September 7, 2022Date of Patent: February 6, 2024Assignee: DANA AUTOMOTIVE SYSTEMS GROUP, LLCInventor: Al Jean-Francois
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Patent number: 11358251Abstract: A grinding device for inner holes has a body, an extension shaft, a nut, and a button assembly. The body has a driving shaft rotatably disposed in the body and a containing hole disposed through a side of the body. The extension shaft has two ends and a concave structure. One of the two ends of the extension shaft is connected with the driving shaft of the body. The concave structure is disposed on the extension shaft, and is aligned with the containing hole of the body after the extension shaft rotates with the driving shaft. The nut is mounted on the other one of the two ends of the extension shaft. The button assembly is mounted in the containing hole of the body, and is able to be pressed and to extend into the concave structure to restrict the extension shaft from rotating.Type: GrantFiled: November 10, 2020Date of Patent: June 14, 2022Inventor: Jian-Shiou Liaw
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Patent number: 8961354Abstract: An infinitely variable speed amplifier comprising a continuously variable unit (“variator”), two differential gear trains, and four shafts. Two of the shafts connect to opposite ends of the variator and to two connections of each differential gear train, respectively. The third connections of the first and second differential gear trains are connected to the input and output shafts respectively. Ratios and other parameters are chosen so that an acceptable range of transmission speeds can be achieved without the use of clutches while also minimizing the power crossing the variator. Furthermore, this invention includes a variant that is a compound infinitely variable speed amplifier that provides a wider performance range.Type: GrantFiled: August 19, 2013Date of Patent: February 24, 2015Inventor: William Robert Brown
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Patent number: 8930055Abstract: The present invention relates to a dual-rotor motor for electric vehicle, wherein an output shaft is at least partly located in a housing and arranged rotatably relative to the housing, a stator is sleeved around the output shaft, an outer three-phase winding is arranged outside the stator, an outer rotor is sleeved around the outer three-phase winding and arranged rotatably relative to the stator, an inner three-phase winding is arranged inside the stator, an inner rotor is inserted in the inner three-phase winding around the output shaft and arranged rotatably relative to the stator, and a continuously variable transmission system with planet gear and dual-rotor motor for electric vehicle and a control method thereof are provided, the dual-rotor motor for electric vehicle of the present invention is designed skillfully and unique in structure, by cooperating with the planet gear, it can sufficiently make use of the wide speed adjustable range of the motor to regulate speeds, compared with an automatic steppType: GrantFiled: June 27, 2011Date of Patent: January 6, 2015Assignee: Shanghai Zhongke Shenjiang Electric Vehicle Co., Ltd.Inventor: Yiqing Yuan
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Patent number: 8771126Abstract: Assuming that N1 and N2 are the respective numbers of pinion rollers (23, 63); ?1 is the ratio between the inner diameter of a ring roller (22) and the outer diameter of a sun roller (21); and ?2 is the ratio between the inner diameter of a ring roller (62) and the outer diameter of a sun roller (61); and it holds that N1=3, and (?1+1)×(?2+1)?24+16×20.5, in the case where N2=3, then it holds that ?1?0.102×(?1+1)×(?2+1)+1.196, and ?1?min[0.204×(?1+1)×(?2+1)+3.123, 7+4×30.5], and in the case where N2=4, then it holds that ?1?(2?20.5)×(?1+1)×(p2+1)/4?1, and ?1?min[0.185×(?1+1)×(?2+1)+1.320, 7+4×30.5].Type: GrantFiled: June 27, 2011Date of Patent: July 8, 2014Assignee: Kabushiki Kaisha Toyota Chuo KenkyushoInventors: Yoshihiro Mizuno, Kisaburo Hayakawa, Hiroyuki Nishizawa, Hiroyuki Yamaguchi, Kiyokazu Sunami
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Patent number: 8460145Abstract: Each of reclining devices is formed so as to have a different size. An external gear wheel of each of the reclining devices has a diameter smaller than an internal gear wheel thereof and has a teeth number different from the internal gear wheel. The internal gear wheels and the external gear wheels of the connection devices respectively have the same teeth number as each other. The internal gear wheels and the external gear wheels of the connection devices are formed such that distances between centers thereof are equal to each other. Further, a meshing line of the internal gear wheel and the external gear wheel of each of the connection devices is formed between two curves defining a meshing range and is drawn as a line that extends from a side of a radially inwardly positioned curve in a circumferential direction in which the two curves are gradually spaced from each other and reaches to a side of a radially outwardly positioned curve.Type: GrantFiled: February 7, 2008Date of Patent: June 11, 2013Assignee: Toyota Boshoku Kabushiki KaishaInventor: Atsutaka Mitsuhashi
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Patent number: 8088036Abstract: A vehicle drive control device includes a continuously variable transmission mechanism (hereinafter referred to as CVT (6) of a torque control type capable of continuously varying a transmission gear ratio, and a controller (34) which controls operations of the CVT (6) and an engine (2). The controller (34) includes a first control section (43; 43A) which controls a torque of the CVT (6) based on a target transmission input torque (TTRN,T), and a second control section (44) which controls a torque of the engine (2) based on a target engine rotation speed (?e,T).Type: GrantFiled: September 29, 2006Date of Patent: January 3, 2012Assignee: JTEKT CorporationInventors: Robert Fuchs, Yasuhiko Hasuda
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Patent number: 8043193Abstract: A gear mechanism for the drive assembly of a heald shaft (1), wherein the gear mechanism (6, 6a, 6b, 6c) comprises an input shaft (7, 7b, 7c) and an output shaft (5, 5b, 5c). The gear mechanism (6, 6a, 6b, 6c) generates a differential angle of rotation between the input shaft (7, 7b, 7c) and the output shaft (5, 5b, 5c) that is superimposed on the angle of rotation and, in dependence on the angle of rotation, is subjected to an oscillating change. This oscillating change can differ from a harmonic oscillation as a result of the non-circular design of the planet gears (11a, 12a, 13a) of the gear mechanism (6, 6b, 6c), thereby making it possible to realize almost any optional movements for the heald shaft (1), with low strain on the gears and the bearings. A simple production method and a compact design are disclosed.Type: GrantFiled: November 26, 2007Date of Patent: October 25, 2011Assignee: Groz-Beckert KGInventor: Gerhard Pohl
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Patent number: 7651436Abstract: A gear mechanism having extremely less backlash, capable of suppressing the rattling noise of gears, having a large loading resistance in the thrust direction, and capable of transmitting high torque by using the gears transmitting a force by the meshing of the gears with each other in place of the transmission of the force by friction. The gear mechanism is formed by disposing the plurality of spur gears in the meshed state with each other. The screw-like gears (2) and (4) are disposed on the same axis as the spur gears (1) and (3) in the meshed state with each other. The screw-like gears (2) and (4) adjacent to each other are formed in screw shapes having lead angles extending in the reverse directions to each other and equal in angle to each other. The spur gear (1) and the screw-like gear (2) are rotated integrally with each other to transmit its rotation to the spur gear (3) and the screw-like gear (4) adjacent to each other.Type: GrantFiled: June 7, 2005Date of Patent: January 26, 2010Inventor: Nobuyoshi Sugitani
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Patent number: 7117759Abstract: A wave gear drive in which wide-area meshing of the rigid internal gear and flexible external gear is achieved, reducing stresses on the bottom rim of the gear teeth and in the vicinity of the major axis of the inner ring surfaces of the wave generator, thereby improving the load capabilities of the wave gear drive.Type: GrantFiled: August 27, 2004Date of Patent: October 10, 2006Assignee: Harmonic Drive Systems, Inc.Inventor: Shoichi Ishikawa
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Patent number: 6889131Abstract: An objective method is provided for selecting gear ratios for use in a motor vehicle transmission having multiple selectable gears. The method includes selecting gear ratios for a specific application includes calculating a low gear ratio, and a high gear ratio based upon vehicle parameters and performance requirements. The total ratio spread is determined by dividing the low gear ratio by the high gear ratio. Using the total ratio spread, a geometric sequence is created with a plurality of terms, such that each of the terms respectively represent the ratio steps between the gears. Lastly, each gear ratio is divided by its respective ratio step plus one to find the gear ratio for the next gear. This method provides an objective method for selecting gear ratios, such that the steps between each of the ratios are uniformly progressive.Type: GrantFiled: August 25, 2004Date of Patent: May 3, 2005Assignee: DaimlerChrysler CorporationInventor: Syed T Razzacki
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Patent number: 6832973Abstract: An apparatus and method to minimize acoustic vibration in a vehicle due to impulsive gear clash loads. Sensors are mounted on the vehicle and are used to sense vehicle vibration generated by the gear clash loads. A first gear, having a plurality of teeth and a second gear, also having a plurality of teeth, are disposed such that upon rotation of the first and second gears, certain ones of the second gear teeth mesh with certain ones of the first gear teeth. An actuator, which is coupled to the first gear, drives the first gear and generates torque pulses. A controller is coupled to the actuator and controls the torque pulses that are transmitted to the first gear. The torque pulses generated by the actuator are adjusted in magnitude and phase so that the first gear teeth vibrate at a predetermined frequencies thereby reducing vibrations and peak tooth loading caused by the meshing of the first gear teeth and the second gear teeth.Type: GrantFiled: July 21, 2000Date of Patent: December 21, 2004Inventor: William A. Welsh
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Patent number: 6827666Abstract: An objective method is provided for selecting gear ratios for use in a motor vehicle transmission having multiple selectable gears. The method includes selecting gear ratios for a specific application includes calculating a low gear ratio, and a high gear ratio based upon vehicle parameters and performance requirements. The total ratio spread is determined by dividing the low gear ratio by the high gear ratio. Using the total ratio spread, a geometric sequence is created with a plurality of terms, such that each of the terms respectively represent the ratio steps between the gears. Lastly, each gear ratio is divided by its respective ratio step plus one to find the gear ratio for the next gear. This method provides an objective method for selecting gear ratios, such that the steps between each of the ratios are uniformly progressive.Type: GrantFiled: September 4, 2002Date of Patent: December 7, 2004Assignee: DaimlerChrysler CorporationInventor: Syed T Razzacki
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Patent number: 6632154Abstract: A gear train has a sun gear with a tooth count e, n (where n is a natural number of 2 or more) planetary gears having a first gear part with a tooth count z1 meshing with the sun gear and a second gear part with a tooth count z2, a fixed internal tooth gear with a tooth count I1 meshing with the first gear part of the planetary gears, and a movable internal tooth gear with a tooth count I2 meshing with the second gear part of the planetary gears, where tooth counts e, z1, z2, I1 and I2 are each a multiple of n. Even if the gear form of each gear has a small module, a planetary gear train mechanism can be configured without raising operating or assembly problems, and it can be miniaturized more than conventional gear trains while still have a sufficient gear reduction ratio.Type: GrantFiled: September 18, 2001Date of Patent: October 14, 2003Assignee: Seiko Epson CorporationInventor: Kenichi Ushikoshi
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Patent number: 6342023Abstract: A gear profile for orbital gear transmission is disclosed in which an outer gear (10) and an inner gear (30) are included. At least one of the gears is constrained for orbital motion to impart rotary motion to the other of the gears. The profile of teeth (34) of inner gear (30) is sinusoidal at least in the vicinity of pitch circle (36) of the gear (30) and the pitch circle (36) coincides with the point of inflection (52) of the sinusoidal profile of the teeth (34). The outer gear (10) has a pitch circle (25) and the point of inflection (19) of the inner gear (30) rolls across the point of the profile of teeth (14) of the outer gear (10) where the pitch circle (25) intersects the profile of the teeth (14). Orbital transmission systems are disclosed in which one or the other of the inner gear (10) or outer gear (30) is mounted on an eccentric (63) which is driven by an input shaft (64).Type: GrantFiled: January 13, 2000Date of Patent: January 29, 2002Assignee: Aimbridge Pty Ltd.Inventor: Eric Paul Willmot
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Patent number: 5918508Abstract: A strain wave gearing is provided with tooth profiles formed taking into account tooth inclination and change in the movement locus of the origin of the tooth profile coordinates, thereby obtaining proper meshing over a wide range. Specifically, a tooth module is denoted as m; the number of teeth of the rigid internal gear as z.sub.C ; the number of teeth, the deddendum, the thickness of the tooth bottom rim and the radius of the neutral circle of the rim of the flexible external gear as z.sub.F, h.sub.fF, t and r.sub.n, respectively; the coefficient of tooth thickness increase of the rigid internal gear and the coefficient of tooth thickness decrease of the flexible external gear both as .tau.; and an auxiliary angle variable .eta.. The basic addendum profiles of both gears are formed according to two equations, taking an x-axis on a datum line and a y-axis on the tooth center line and taking .+-. of the first equation as positive for the flexible external gear and as negative for the rigid internal gear.Type: GrantFiled: September 24, 1997Date of Patent: July 6, 1999Assignee: Harmonic Drive Systems, Inc.Inventor: Shoichi Ishikawa
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Patent number: 5704865Abstract: An eccentric gear comprises first and second gear rings (7,10) of which the one (7) has internal, straight cogs and the other (10) a smaller number of external cogs. At least one gear ring has a conical form with a large end (A--A) and a small end (B--B), the other gear ring (10) having a smaller pitch diameter than the first one (7) and being eccentrically mounted in bearings relative to the first one. Axes of symmetry (24,25) of the respective gear rings form an angle (.alpha.) with each other. The contact points or the locations of engagement between the flanks of the cogs in the one gear ring and the opposed flanks of the cogs in the other gear ring are substantially located along a helical line which extends in axial direction between said large and small ends.Type: GrantFiled: February 27, 1996Date of Patent: January 6, 1998Assignee: Scandrive I Hallstahammar ABInventor: Gustav Rennerfelt
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Patent number: 5658213Abstract: In a power train control apparatus including an engine, an automatic transmission having a torque converter, and a control unit for controlling the engine and the automatic transmission, the control apparatus is provided with a microcomputer for calculating and estimating values of the input shaft torque and a gear ratio of the automatic transmission. Various characteristics of the engine and the torque converter are obtained in advance by experiments, such as the relationship between an engine torque and an engine speed, and that between a pump capacity coefficient data and a slip ratio of the torque converter. Thereafter, data tables are made by using these characteristics, and control factors required to control the engine and the automatic transmission are made as an equation in relation to the input shaft torque and the gear ratio so as that they can be calculated by the microcomputer.Type: GrantFiled: July 25, 1995Date of Patent: August 19, 1997Assignees: Hitachi, Ltd., Hitachi Automotive Engineering Co., Ltd.Inventors: Kazuhiko Sato, Masahiko Ibamoto, Hiroshi Kuroiwa
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Patent number: 5509866Abstract: An epicyclical system of miter, bevel, worm and spur gears, plus joining members that may be adapted to, or be embodied in, a wide variety of devices in the field of applied mechanics including, but not limited to: (a) absorption of energy from fluid streams, (b) timing and tracking mechanisms, (c) mechanical power transmission; (d) generation of uniform or intermittent sine wave velocities in a multitude of helicoid patterns.Type: GrantFiled: June 28, 1994Date of Patent: April 23, 1996Assignee: Univerg Research Netwerg, Ltd.Inventor: Gerald N. Weightman
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Patent number: 5292289Abstract: A planetary speed-up and -down gearing comprising an external gear having outer teeth (7A) defined by a trochoidal curve and an internal gear having outer pins (9) internally meshed with the outer teeth (7A) of the external gear and being eccentric with respect to the external gear, the external gear and the internal gear being meshed and rotated eccentrically and swingingly relative to each other, so that phases of the external gear and the internal gear are shifted by a difference in the number of teeth between both said gears for each of the eccentric and swinging rotations, to thereby take out, as an output, rotation corresponding to the above difference in phase.Type: GrantFiled: September 1, 1992Date of Patent: March 8, 1994Assignee: Sumitomo Heavy Industries, Ltd.Inventors: Seishiro Ogata, Atsushi Takahashi, Hideyoshi Tanaka
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Patent number: 5221237Abstract: A cylindrical member driven by a planetary gear arrangement traverses an epitrochoid path to periodically enter a radial slot in an arm or disc rotating the arm or disc through 180.degree.. By selecting the parameters appropriately the cylindrical member is caused to enter and leave the radial slot along a tangential path such that no first or second derivative discontinuities are present in the motion of the arm or disc. Several embodiments are disclosed for achieving either one or two incremental rotations of an output shaft for a single revolution of an input shaft with various speed reducing gear trains.Type: GrantFiled: August 27, 1992Date of Patent: June 22, 1993Inventor: Theodore Weber
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Patent number: 5215323Abstract: By incorporating an infinitely adjustable, variable speed transmission unit into a bicycle driving mechanism, it becomes possible to vary the speed of the bicycle in a very easy and continuous manner from any predetermined maximum value of rotation in the forward direction to zero. By using a similar, infinitely adjustable, variable speed transmission unit in combination with a standard, two speed and reverse gear box, a very efficient automotive transmission system is also achieved, having a stepless speed control with a large power input.Type: GrantFiled: February 25, 1992Date of Patent: June 1, 1993Inventor: Ben Cowan
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Patent number: 5178587Abstract: A gear differential having multiple gear trains interconnecting a pair of output shafts is provided with an arrangement of gearing having an expanded relationship between tooth numbers of the gearing for fitting the gear trains into mesh. The gearing includes two side gears (20 and 21) coupled to respective output shafts and three pairs of combination gears (24 and 25, 26 and 27, and 28 and 29) for interconnecting the two side gears. Each of the combination gears includes a middle gear portion (40) and two end gear portions (42 and 44). The middle and end gear portions have respective numbers of teeth that share a greatest common factor (GCF) that is more than one but less than the number of teeth in the middle gear portion.Type: GrantFiled: September 24, 1991Date of Patent: January 12, 1993Assignee: Zexel-Gleason USA, Inc.Inventor: Shiro Ichiki
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Patent number: 5121936Abstract: By incorporating an infinitely adjustable, variable speed transmission unit into a bicycle driving mechanism, it becomes possible to vary the speed of the bicycle in a very easy and continuous manner from any predetermined maximum value of rotation in the forward direction to zero. By using a similar, infinitely adjustable, variable speed transmission unit in combination with a standard, two speed and reverse gear box, a very efficient automotive transmission system is also achieved, having a stepless speed control with a large power input. spThis application is a continuation-in-part application of Ser. No. 07/388,863 filed Aug. 3, 1983 which in turn is a continuation-in-part application Ser. No. 07/293,422 filed Jan. 4, 1989, now abandoned.Type: GrantFiled: June 12, 1990Date of Patent: June 16, 1992Inventor: Ben Cowan
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Patent number: 5088970Abstract: A differential gear assembly of the type used in automotive and truck axles having multiple gear trains for interconnecting axle ends is provided with gearing components having a particular relationship between tooth numbers for simplifying assembly requirements of the differential. For example, each gear train includes a pair of combination gears (40, 50) formed with center worm wheel portions (42, 52) and first (44, 54) and second (46, 56) spur portions at either end. The tooth numbers n.sub.s of the spur portions (44, 54 and 46, 56) are made an integer multiple k of the tooth numbers n of the worm wheel portions (42, 52) of each combination gear (40, 50). The relationship can be expressed as follow:n.sub.s =k-n; k>1 andan integer=2(N.k)/w andN=no. of side gear teethW=no. of gear trainsThis enables the respective gear trains w to be assembled in a properly timed relationship at an expanded number of easily recognizable rotational positions.Type: GrantFiled: May 25, 1990Date of Patent: February 18, 1992Assignee: Zexel-Gleason USA, Inc.Inventor: James S. Dye
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Patent number: 5080636Abstract: A cylindrical member driven by a planetary gear arrangement traverses an epitrochoid path to periodically enter a radial slot in an arm or disc rotating the arm of disc through 180.degree.. By selecting the parameters appropriately the cylindrical member is caused to enter and leave the radial slot along a tangential path such that no first or second derivative discontinuities are present in the motion of the arm or disc. Several embodiments are disclosed for achieving either one or two incremental rotations of an output shaft for a single revolution of an input shaft.Type: GrantFiled: January 22, 1991Date of Patent: January 14, 1992Inventor: Theodore Weber
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Patent number: 5030184Abstract: An eccentric gear comprising a stationary gear wheel (2) and an eccentric gear wheel (9). The eccentric wheel is freely mounted on the input shaft and is driven round by eccentric means (4, 6) causing the eccentric wheel to roll round the internal teeth on the stationary wheel. A driving dog transmits the slow rotation of the eccentric wheel to an output shaft (14). Distinguishing for the invention is that the teeth are corrected such that the eccentric wheel is adjusted with the aid of the two eccentric means such that there is practically no backlash. A computer calculated least clearance between respective top lands on the teeth is obtained with respect to tooth meshing. The eccentric means comprises two cylindrical sleeves arranged eccentrically one in the other. At one end part of each of the sleeves, one of which is arranged eccentrically in the other, there is a radially outstanding tongue (5, 7).Type: GrantFiled: July 21, 1989Date of Patent: July 9, 1991Inventor: Gustav Rennerfelt
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Patent number: 4944718Abstract: A angular velocity modulating device comprises: a primary angular velocity modulating means including a first non-circular gear which is an internal gear rotatably supported and a second non-circular gear which is an external gear mounted on a second rotary shaft and engaged with the first non-circular gear; a secondary angular velocity modulating means including the first non-circular internal gear and a third non-circular gear which is an external gear mounted on a third rotary shaft and engaged with the first non-circular gear; a first frame rotatably supporting the first non-circular gear and the second rotary shaft; and a second frame rotatably supporting the third rotary shaft, the ratio in angular velocity of the third rotary shaft to the second rotary shaft being the quotient of the secondary angular velocity ratio of the first and second non-circular gears divided by the primary angular velocity ratio of the first and third non-circular gears, whereby the device can be small in size in a radial direcType: GrantFiled: June 16, 1989Date of Patent: July 31, 1990Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Toshiyuki Takahara, Akira Takami
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Patent number: 4928556Abstract: A robot arm drive apparatus of an industrial robot comprising: an electric motor having a drive shaft; a first robot member having the electric motor mounted thereon; a second robot member rotatably supported on the first robot member; and reduction gears for reducing rotation of the electric motor and then transmitting to the second robot member; the reduction gears comprising a planetary reduction gear and furthermore an additional reduction gear which is purposely provided so that the number of rotations of the electric motor, at which the resonance of a drive system comprising the electric motor, the second robot member and the reduction gear means occurs, is shifted from a predetermined operational region of the electric motor.Type: GrantFiled: February 26, 1988Date of Patent: May 29, 1990Assignee: Teijin Seiki Co., Ltd.Inventors: Kazuyuki Matsumoto, Masataka Hashimoto, Michiyoshi Iwata
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Patent number: 4912993Abstract: A starter includes a speed changing mechanism for transmitting rotational force of an electric motor to a pinion gear capable of being brought into or out of engagement with a ring gear of an engine. The speed changing mechanism includes a geared stepless speed changer. A speed reduction ratio is controlled responsive to a load change by means of an input shaft, an output shaft, and input and output frames rotatable relative to each other about the input shaft. A ratio of angular velocities of the input and output shafts is related to an angle of rotation between the input and output frames.Type: GrantFiled: October 6, 1988Date of Patent: April 3, 1990Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Keiichi Konishi, Akira Takami