Steering By Driving Patents (Class 477/1)
-
Patent number: 9416332Abstract: One embodiment may include a gear assembly comprising at least one pair of meshing gears situated inside a gear case having a sump portion and a wall portion. A gear oil mixture may be disposed at least in the sump portion. At least one gear is immersed partially or fully in the oil mixture. The oil mixture comprises a hydrocarbon oil base and a coolant having an endothermic liquid/vapor transition at a temperature between the lower and upper operating temperatures of the gear assembly.Type: GrantFiled: November 17, 2010Date of Patent: August 16, 2016Assignee: GM Global Technology Operations LLCInventors: Gregory Mordukhovich, James L. Linden, Andrew M. Mance
-
Publication number: 20150065293Abstract: A vehicle driving system includes: a left wheel driving system having a first motor and a first speed changer; a right wheel driving system having a second motor and a second speed changer; a motor controller which controls the first motor and the second motor, a rotation restricting unit which can be shifted between a released state and an applied state; and a rotation restricting unit controller which controls the rotation restricting unit. When the rotation restricting unit controller shifts the rotation restricting unit from the applied state to the released state, the motor controller controls the first motor and the second motor so that a torque sum of the first motor and the second motor approaches zero while maintaining a torque difference between the first motor and the second motor.Type: ApplicationFiled: March 19, 2013Publication date: March 5, 2015Applicant: HONDA MOTOR CO., LTD.Inventors: Satoshi Ando, Sei Shinohara
-
Publication number: 20140357446Abstract: A steering system for a differential steered self-propelled agricultural windrower, windrower speed and direction controlled by adjusting the pivotal position of rotatable pintel arms to control the output of a pair of tandem-mounted hydraulic drive pumps and provide motive power for the windrower. A control input shaft that is both rotatable and axially moveable manages the relative positioning of the pintel arms. A hydraulic steering motor is operably connected to the input shaft. Rotation of the hydraulic steering motor is managed by a steering control valve attached to a cab-mounted windrower steering wheel.Type: ApplicationFiled: May 30, 2013Publication date: December 4, 2014Inventors: TODD B. PIERCE, PHILIP J. EHRHART, JEFFREY FAY, II, MARK D. LAYTON
-
Patent number: 8340869Abstract: A vehicle includes a contact-position-dependent type operational intention determining unit that detects a change in posture of a rider using posture sensors for a backrest disposed in areas of a backrest with which left and right shoulder blades of the rider come into contact, and thereby determines whether there is an operational intention of the rider; and a left-right amount-of-change comparison type turn intention determining unit that determines, only when it is determined that there is an operational intention, whether there is a left or right turn intention of the rider from a difference between sensor output values located left-right symmetrically.Type: GrantFiled: July 18, 2012Date of Patent: December 25, 2012Assignee: Panasonic CorporationInventors: Yumi Wakita, Yumiko Kato, Mizuho Sakakibara, Kenichi Inoue
-
Publication number: 20120238403Abstract: A work vehicle includes a pair of electric motors independently running and driving right and left running wheels in a state of being able to create straight running state and turning running; a pair of right and left change speed operation tools independently manually operated and performing a change speed operation to the right and left running wheels; and a controller controlling operation. The controller controls the operation of the respective electric motors by setting target speeds with regard to the respective electric motors such that the speed difference in the target speeds is smaller than the speed difference corresponding to the difference in the operation positions of the respective change speed operation tools by a set amount in a case where the operation positions of the respective change speed operation tools are different between right and left.Type: ApplicationFiled: September 23, 2011Publication date: September 20, 2012Applicant: KUBOTA CORPORATIONInventors: Kazuo KOIKE, Hirokazu ITO
-
Patent number: 8185279Abstract: A control system (100) for traction transmission has at least two multi capacity motors (M1, M2), which are adapted to rotate a vehicle's wheels (J1, J2) and which multi capacity motor (M1) is arranged to rotate a traction wheel (J2), and the multi capacity motor (M2) is arranged to rotate another traction wheel (J1), whereby motor parts (M1a and M2a) of partial rotational volumes of the multi capacity motors (M1, M2) can be connected in series, whereby the anti-slip is on.Type: GrantFiled: January 25, 2008Date of Patent: May 22, 2012Assignee: Sampo-Hydraulics OyInventor: Roni Ryyppö
-
Patent number: 8051687Abstract: A system, method, and computer program product for detecting and compensating for a traction steer event is provided. A first wheel speed of a first driven wheel is compared with a second wheel speed of a second driven wheel to determine whether a wheel slip condition has occurred. If a wheel slip condition is determined to have occurred, a current operating state of a vehicle is compared to an expected operating state of the vehicle to determine if a traction steer event has occurred. If a traction steer event is determined to have occurred, brake pressure is selectively applied to the first or second driven wheel to compensate for the traction steer event.Type: GrantFiled: October 31, 2007Date of Patent: November 8, 2011Assignee: GM Global Technology Operations LLCInventors: David T. De Carteret, Larry G. Gepfrey, Gregory K. Peterson, Mark S. Hogle
-
Publication number: 20100120578Abstract: A drive and steering control system for an endless track vehicle such as a sugar cane harvester. A dual path hydrostatic drive has a pair of variable volume pumps connected for bidirectional flow to respective hydraulic motors driving a pair of endless tracks. A speed control lever and steering wheel mechanism each provide control inputs to a microprocessor which in turn controls the variable volume hydrostatic pumps to control vehicle velocity and turning in a way that matches control for wheeled vehicles. RPM sensors for the hydraulic motors provide a feedback signal that is used to compensate for equipment variation and to keep the vehicle on the course intended by the operator.Type: ApplicationFiled: November 7, 2008Publication date: May 13, 2010Inventors: HICHEM BOUGUERRA, BRYAN DUGAS
-
Publication number: 20090032314Abstract: A machine is provided. The machine has a frame, an implement attached to a front end, a power source, a first and a second drive motor, a left front and rear axle, and a right front and rear axle. The first and second drive motors are powered by the power source, and each has an inner and an outer sprocket. The left rear axle is coupled to the inner sprocket of the first drive motor and rotatably coupled to the frame. The left front axle is coupled to the outer sprocket of the first drive motor and rotatably coupled to the frame. The right rear axle is coupled to the inner sprocket of the second drive motor and rotatably coupled to the frame. The right front axle is coupled to the outer sprocket of the second drive motor and rotatably coupled to the frame.Type: ApplicationFiled: August 3, 2007Publication date: February 5, 2009Inventors: Justin D. Speichinger, Michael C. Layko
-
Patent number: 7472010Abstract: A transmission control system is provided for a work machine that has a transmission and a traction device with a brake mechanism. The transmission control system has a speed sensor configured to generate a signal indicative of a travel speed of the work machine. The transmission control system also has a controller in communication with the speed sensor and the brake mechanism. The controller is configured to determine when a transmission gear change is desired. The controller is further configured to adjust operation of the brake mechanism in response to the signal from the speed sensor when the transmission gear change is desired.Type: GrantFiled: September 27, 2004Date of Patent: December 30, 2008Assignee: Caterpillar Inc.Inventors: Norval P. Thomson, Kent A. Casey
-
Patent number: 7433768Abstract: In a method, a steeringwheel torque for the steering wheel of a motor vehicle is determined. In this context, a steering angle for steered wheels is predefined by the driver by means of the steering wheel. A steering torque which represents the forces on the vehicle axle acts on the steering wheel. A desired manual torque (M_soll) is determined here using at least one axle model. The desired manual torque is then superimposed on the actual steeringwheel torque (M_ist).Type: GrantFiled: July 16, 2003Date of Patent: October 7, 2008Assignee: Daimler AGInventors: Werner Bernzen, Wilfried Huber, Volker Maass, Martin Moser, Reinhold Schneckenburger, Christian Urban
-
Patent number: 7360616Abstract: A method for controlling and regulating a power train of a hybrid vehicle and a power train of a hybrid vehicle having one internal combustion engine, one electric machine, one shifting element and one output in a power flow of the power train and designed with continuously variable transmitting capacity and one clutch device and the internal combustion engine. The electric machine can be operatively interconnected via the clutch device, the hybrid vehicle being optionally driveable via the electric machine and/or via the internal combustion engine and the internal combustion engine can be started via the electric machine. In the operation of the power train, the transmitting capacity of the shifting element during the starting operation of the internal combustion engine is adjusted so that on the output of the power train, a torque abuts which is independent of the starting operation of the internal combustion engine.Type: GrantFiled: December 13, 2004Date of Patent: April 22, 2008Assignee: ZF Friedrichshafen AGInventor: Peter Schiele
-
Patent number: 7328758Abstract: A self-propelled vehicle particularly for making turns with tight turning radii, comprising a chassis provided with two driving wheels forming at least one driving portion, and which supports a motor kinematically connected to a motion distribution shaft. A functional connection is provided between the motion distribution shaft and each one of the driving wheels and is individually activatable or deactivatable on command for independent actuation of the driving wheels. A steering adapted to act on the functional connection, the latter comprising, between the motion distribution shaft and at least one of the driving wheels, a respective clutch coupling, activatable or deactivatable by the steering device.Type: GrantFiled: February 23, 2005Date of Patent: February 12, 2008Assignee: Comac S.p.A.Inventor: Massimiliano Ruffo
-
Patent number: 7326141Abstract: A transmission drive system (TDS) has two AC induction traction motors, each operatively coupled to two semi-independent coaxial traction shafts, and two AC induction steer motors coaxially mounted on a common steer axis parallel to the coaxial traction shafts. A steering gear assembly, preferably between the traction and steering motors, has a common steer input shaft operatively connected to the two AC induction steering motors. Two planetary gear sets have the two traction shafts being operatively connected with one of a two planet gear carriers, or two ring gears, respectively. The other of the planet gear carriers or the ring gears are operatively connected with each other. Two offset gears mounted to the steer input shaft and meshing with two sun gears, respectively, including a reversing idler gear interposed between one of the two offset gears and one of the two sun gears.Type: GrantFiled: March 13, 2006Date of Patent: February 5, 2008Assignee: BAE Systems Information and Electronic Systems Integration Inc.Inventors: Arthur P. Lyons, Bart Winter Mancini
-
Publication number: 20070184935Abstract: The “u-turn” signal would be a safety device that would be standard in all motorized vehicles as a normal safety feature such as windshield wipers, headlights, turning signals etc. It would be best to be incorporated as part of the turning signal apparatus but can also be just a button such as the emergency flashers are. Presently when a vehicle is making a u-turn they are only truly able to show that intention by a hand signal which is rarely done . This invention will prevent rear end accidents and also accidents between the vehicle making the u-turn and a vehicle which is entering the same roadway via a right turn on red.Type: ApplicationFiled: February 3, 2006Publication date: August 9, 2007Inventors: Richard Wallis, Maria Wallis
-
Patent number: 7177744Abstract: An elastic support assembly for an electric power steering apparatus in which a worm shaft is supported movably in a rotation axis direction through the elastic support assembly includes: a pair of first and second members relatively moving in the rotation axis direction according to a movement of the worm shaft; an elastic body provided between the first and second members in the rotation axis direction; and a cover which covers an outer periphery part of the elastic body from a radial direction of the worm shaft and is connected to the first member.Type: GrantFiled: February 12, 2004Date of Patent: February 13, 2007Assignee: Koyo Seiko Co., LtdInventors: Hajime Tanaka, Hisatake Yamada, Norihisa Nishikawa, Hideo Kometani
-
Patent number: 6968262Abstract: Steering angle is determined by the combined use of a potentiometer and a rotary encoder, and the correction of the error in the determination of the steering angle based on the time-dependent change of the potentiometer.Type: GrantFiled: November 13, 2003Date of Patent: November 22, 2005Assignee: Koyo Seiko Co., Ltd.Inventors: Masayasu Higashi, Ryouhei Hayama
-
Patent number: 6654676Abstract: An object is to provide a steering system for a tracklaying vehicle which is capable of preventing overrun of a motor during a pivot turn irrespective of the load of the road surface and does not cause a shortage of power during a turn. The steering system is comprised of a pair of brakes for right and left output shafts and designed to transmit the driving force of a hydraulic motor to the output shafts through a planetary gear mechanism. A transmission of a driving force from the hydraulic motor to the planetary gear mechanism is interrupted after concurrently carrying out actuation of a brake for either one of the right and left output shafts and a transmission of a driving force from the hydraulic motor to the planetary gear mechanism for a specified period of time, when the vehicle carries out a pivot turn. During a pivot turn of the vehicle, the engine is controlled such that a vehicle body speed obtained by a bevel shaft rotational speed detector becomes equal to a specified value.Type: GrantFiled: March 22, 2002Date of Patent: November 25, 2003Assignee: Komatsu Ltd.Inventors: Tomohiro Nakagawa, Shigeru Yamamoto, Kazuyuki Suzuki
-
Publication number: 20030055543Abstract: A controller (32) for a vehicular system (10) that includes a hand-wheel (16) and an electric motor (34) includes a torque-assist function (56) responsive to a signal representing the torque applied to the hand-wheel (16) for providing a torque-assist command to the motor (34), and a steering-pull compensator (52) responsive to a signal representing a valid ignition cycle for modifying the torque-assist command to the motor (34) by an offset corresponding to a detected steering-pull condition; where the method of control includes receiving the signal indicative of the torque applied to the hand-wheel (16), providing a torque-assist command to the motor (34) in response to the received torque signal, detecting an enabling signal related to the signal representing a valid ignition cycle, quantifying a steering-pull condition in response to the received and detected signals, and modifying the torque-assist command to the motor (34) by an offset corresponding to the quantified steering-pull condition.Type: ApplicationFiled: September 18, 2001Publication date: March 20, 2003Inventors: Sanket S. Amberkar, Ashok Chandy, Kathryn L. Pattok, Mark P. Colosky
-
Patent number: 6484828Abstract: A mobile cultural machine including right and left traction members, a transmission, and a main speed change device operable to transmit, at any speed ratio, a driving force from an engine through the transmission to the traction members so that they are driven at any traveling speed. A steerage and a steering devise operate cause the steerage to differentiate the traveling speeds between traction members. The traveling speeds are reduced in response to the extent to which the steering device is operated, so that a machine running straight may smoothly be controlled to enter a spinning turn at the end of a row.Type: GrantFiled: January 30, 2002Date of Patent: November 26, 2002Assignee: Yanmar Agricultural Equipment Co., Ltd.Inventors: Shigemi Hidaka, Daigo Yokoyama
-
Patent number: 6408960Abstract: A mobile cultural machine including right and left traction members, a transmission, and a main speed change device operable to transmit, at any speed ratio, a driving force from an engine through the transmission to the traction members so that they are driven at any traveling speed. A steerage and a steering device operate to cause the steerage to differentiate the traveling speeds between traction members. The traveling speeds are reduced in response to the extent to which the steering device is operated, so that a machine running straight may smoothly be controlled to enter a spinning turn at the end of a row.Type: GrantFiled: September 25, 2000Date of Patent: June 25, 2002Assignee: Yanmar Agricultural Equipment Co., Ltd.Inventors: Shigehiro Hidaka, Daigo Yokoyama
-
Patent number: 6360149Abstract: A vehicle steering command module as disclosed wherein the command module is necessary to start and control the motion of a vehicle, and once removed from the vehicle the command module can function as a personal computer. The vehicle steering command module includes a housing having a computer processing unit and a connection port. The connection port releasably connects the command module to one of a pair of spaced apart mating connection ports on an instrument panel of the vehicle, thereby completing a steer by wire circuit of the vehicle. Rotation of the command module controls the direction of travel of the vehicle when the command module is connected to one of the mating connection ports. The command module includes at least one input device operably connected to the computer processing unit. A cover of the steering command module is moveable between a closed position and an opened position, and includes a display screen operably connected to the computer processing unit.Type: GrantFiled: December 8, 1999Date of Patent: March 19, 2002Assignee: Delphi Technologies, Inc.Inventors: Ki C. Kwon, Ronald Henry Dybalski, Vincent Lee Brooks
-
Patent number: 6196342Abstract: A steering mechanism that controls a drive and steer transmission and that causes the transmission to execute turns in the direction a steering wheel is turned when operating in either the forward or reverse direction of travel. In response to operator engagement of a drive control, an actuation linkage shifts an elongate member within a slot formed in a cam member that pivots in response to turning of a steering wheel. Shifting of the rod member between two positions on either side of the cam member pivot axis causes the drive and steer transmission to steer the vehicle in the desired direction when the vehicle is traveling in both forward and reverse.Type: GrantFiled: October 5, 1999Date of Patent: March 6, 2001Assignee: Deere & CompanyInventors: Richard Donald Teal, Eugene Gary Hayes, David Lewis Marchese, Barry Joseph Goebert, Wayne Robert Hutchinson
-
Patent number: 6152248Abstract: A mobile agricultural machine has a pair of right and left traction members (2), a transmission (23,24), a main speed change device (68) operable to transmit at any speed ratio a driving force from an engine (21) through the transmission to the traction members so that the traction members are driven at any traveling speeds. The machine further has a steerage (26,27), and a steering device (19) operable to cause the steerage to differentiate the traveling speeds between the traction members (2). The traveling speeds are reduced in response to an extent to which the steering device (19) is operated, so that the agricultural machine running straight for an agricultural work along its running course that is being adjusted may smoothly be controlled merely by a continuous manual operation to make a spinning turn on a bare end of the farm for the next course of the work.Type: GrantFiled: September 23, 1998Date of Patent: November 28, 2000Assignee: Yanmar Agricultural Equipment, Lts.Inventors: Shigehiro Hidaka, Daigo Yokoyama
-
Patent number: 6129164Abstract: A steering mechanism that controls a drive and steer transmission and that causes the transmission to execute turns in the direction a steering wheel is turned when operating in either the forward or reverse direction of travel. In response to operator engagement of a drive control, an actuation linkage shifts an elongate member within a slot formed in a cam member that pivots in response to turning of a steering wheel. Shifting of the rod member between to positions on either side of the cam member pivot axis causes the drive and steer transmission to steer the vehicle in the desired direction when the vehicle is traveling in both forward and reverse.Type: GrantFiled: March 26, 1999Date of Patent: October 10, 2000Assignee: Deere & CompanyInventors: Richard Donald Teal, Eugene Gary Hayes, David Lewis Marchese, Barry Joseph Goebert
-
Patent number: 6033337Abstract: In a torque splitting device for distributing an input torque applied to an input member to a pair of output members adapted to be coupled with right and left driven wheels of a vehicle at an adjustable distribution ratio, the distribution ratio is determined in such a way that the understeer and oversteer tendencies of the vehicle under a positive or negative drive condition while turning a curve is appropriately controlled. In particular, it is highly desirable to prevent an understeer tendency from appearing while turning a curve. Therefore, when the vehicle is under a positive drive condition while tuning a curve, a yaw moment is produced by an appropriate torque distribution which assists the vehicle to turn in such a way that the understeerg condition is canceled.Type: GrantFiled: November 11, 1997Date of Patent: March 7, 2000Assignee: Honda Giken Kogyo Kabushiki KaishaInventors: Shinji Ohkuma, Shoji Akaogi
-
Patent number: 5879265Abstract: A method and apparatus for the operation of a vehicle with a plurality of electric motors includes an electric motor assigned to each wheel of an axle of the vehicle. Attached to each of the electric motors is a shiftable transmission (at least two-speeds). Shifting of a transmission is performed as a function of the total efficiency of the particular motor when reaching a predetermined shifting point. The transmissions attached to the electric motors are shifted, delayed in time. The shifting of the transmission attached to a first electric motor is monitored and the shifting of a transmission attached to a second motor is performed only when the shifting of the first transmission is completed. No interruption of the traction force occurs in the drive system.Type: GrantFiled: May 14, 1997Date of Patent: March 9, 1999Assignee: Voith Turbo GmbH & Co. KGInventor: Manfred Bek
-
Patent number: 5569109Abstract: A geared steering system, which is capable of actuating rightside and leftside driving mechanisms to ensure efficient operation of a crawler vehicle, has a geared steering device (30) and a control system. The geared steering device (30) has one power input shaft (31), leftside and rightside steering brakes (38L, 38R) and leftside and rightside direct-coupled clutches (36, 44), one turn clutch (46), three planet gear trains (40, 43, 48), leftside and rightside power output shafts (32L, 32R) coupled to leftside and rightside steering brake hubs (34L, 34R), and a hydraulic turning motor (83) coupled to the turn clutch (46) with gears.Type: GrantFiled: June 27, 1994Date of Patent: October 29, 1996Assignee: Kabushiki Kaisha Komatsu SeisakushoInventor: Toshikazu Okada
-
Patent number: 5558590Abstract: A geared steering device (30) selectively operates rightside and leftside driving mechanisms (2,3) of a crawler vehicle (1) for more efficient operation of the crawler vehicle. The geared steering device (30) comprises a power input drive element (33) for inputting a driving power from a prime mover (7), rightside and leftside steering brakes (38R, 38L), rightside and leftside direct-coupled clutches (36, 44), a turn clutch (46), three arrays of planet gear trains (40, 43 and 48), and power output shafts (32R, 32L) coupled to right and leftside steering brake hubs (34R, 34L). A control unit compares an actual steering ratio of a geared steering device (30) with a designated steering ratio, outputs control signals to respective solenoid valves for controlling the direct-coupled clutches, the turn clutch or a steering brake so as to cause the actual steering ratio to approximate the designated steering ratio.Type: GrantFiled: January 28, 1994Date of Patent: September 24, 1996Assignee: Kabushiki Kaisha Komatsu SeisakushoInventors: Toshikazu Okada, Hiroshi Itogawa, Hidekazu Nagase
-
Patent number: 5477454Abstract: A turning system for use in a track-laying vehicle comprising: a power source; a steering motor driven by the rotation of the power source, for driving crawler belts provided at both sides of the vehicle such that a relative travel difference is caused between the crawler belts, thereby turning the vehicle rightwards or leftwards; a power source revolution speed detector for detecting the actual revolution speed of tile power source; and a steering motor control unit for performing a control such that, a target revolution speed set for the steering motor is decreased when the actual revolution speed of the power source detected by the power source revolution speed detector decreases below a target revolution speed set for the power source by a specified revolution speed or more.Type: GrantFiled: June 30, 1994Date of Patent: December 19, 1995Assignee: Kabushiki Kaisha Komatsu SeisakushoInventors: Tsutomu Ishino, Ryoichi Maruyama, Hideki Yamada
-
Patent number: 5477455Abstract: A turning control system for use in a track-laying vehicle comprising: a steering motor for driving crawler belts provided at both sides of the vehicle such that a relative travel difference is caused between the crawler belts, thereby turning the vehicle rightwards or leftwards; a steering instructing device which can be displaced from a neutral position by operation and which instructs, in accordance with its displacement direction and displacement distance, a turning direction and a turning radius for the vehicle, the turning radius decreasing as the displacement distance increases; a displacement detector for detecting the displacement of the steering instructing device; a vehicle speed detector for detecting the vehicle speed at which the vehicle moves forwards or backwards; and a steering motor revolution speed control unit for controlling the revolution speed of the steering motor such that the revolution speed of the steering motor becomes proportional to the vehicle speed detected by the vehicle speeType: GrantFiled: June 30, 1994Date of Patent: December 19, 1995Assignee: Kabushiki Kaisha Komatsu SeisakushoInventors: Tsutomu Ishino, Ryoichi Maruyama, Hideki Yamada
-
Patent number: 5473541Abstract: A steering control system for use in a track-laying vehicle comprising: a power source; a steering motor driven by the rotation of the power source, for driving crawler belts provided at both sides of the vehicle such that a relative travel difference is caused between the crawler belts, thereby turning the vehicle rightwards or leftwards; a steering instructing device which can be displaced from a neutral position by operation and which instructs, according to the direction and distance of its displacement, a turning direction and a turning radius for the vehicle, the turning radius decreasing as the displacement distance increases; a displacement detector for detecting the displacement of the steering instructing device; and a steering motor revolution speed control unit for obtaining a target steering motor revolution speed which is made proportional to the revolution speed of the power source based on the displacement of the steering instructing device detected by the displacement detector and controllingType: GrantFiled: June 30, 1994Date of Patent: December 5, 1995Assignee: Kabushiki Kaisha Komatsu SeisakushoInventors: Tsutomu Ishino, Ryoichi Maruyama, Hideki Yamada
-
Patent number: RE36151Abstract: A turning control system for use in a track-laying vehicle comprising: a steering motor for driving crawler belts provided at both sides of the vehicle such that a relative travel difference is caused between the crawler belts, thereby turning the vehicle rightwards or leftwards; a steering instructing device which can be displaced from a neutral position by operation and which instructs, in accordance with its displacement direction and displacement distance, a turning direction and a turning radius for the vehicle, the turning radius decreasing as the displacement distance increases; a displacement detector for detecting the displacement of the steering instructing device; a vehicle speed detector for detecting the vehicle speed at which the vehicle moves forwards or backwards; and a steering motor revolution speed control unit for controlling the revolution speed of the steering motor such that the revolution speed of the steering motor becomes proportional to the vehicle speed detected by the vehicle speeType: GrantFiled: July 25, 1996Date of Patent: March 16, 1999Assignee: Kabushiki Kaisha KomatsuInventors: Tsutomu Ishino, Ryoichi Maruyama, Hideki Yamada