Patents by Inventor Tetsuro Hamada

Tetsuro Hamada has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6041904
    Abstract: A power transmitting system having an input shaft, a driven bevel gear, a follower bevel gear and a clutch drive shaft accommodated in center casings. Left and right electromagnetic clutches connected to the clutch drive shaft are accommodated in left and right side casings. Oil for lubricating the electromagnetic clutches is supplied from an oil pump accommodated in the center casings and driven by the clutch drive shaft through oil passages and axially defied in the clutch drive shaft and left and right output shafts. Thus, the length of the oil passages for supplying the oil from the oil pump to the clutches can be minimized to provide a reduction in size of the power transmitting system.
    Type: Grant
    Filed: January 13, 1998
    Date of Patent: March 28, 2000
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Koji Kuroda, Takayuki Yakou, Kazunori Kobayashi, Kazuyuki Suetake, Tetsuro Hamada
  • Patent number: 6024182
    Abstract: This is a connecting device (7) to be interposed between left and right wheels (5L, 5R) of a vehicle. It enables to perform a starting assistance control, a cornering control to improve the cornering performance by positively generating a difference rotation between left and right wheels, and a differential limiting control for restricting the difference rotation between the left and right wheels. There are provided: a differential gear (8) having a first rotational element (8a), and second and third rotational elements (8b, 8c) so arranged that, when one of them rotates in normal direction relative to the first rotational element (8a), the other thereof rotates in the reverse direction; and a driving source (9) connected to the first rotational element (8a). One of the second and third rotational elements, e.g.
    Type: Grant
    Filed: April 25, 1997
    Date of Patent: February 15, 2000
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Kentaro Arai, Yoshihiro Kanamaru, Isamu Hashizume
  • Patent number: 6008606
    Abstract: A starting assistance device for a vehicle has an electric motor and a dog clutch which is switched on at the time of starting of the vehicle to thereby transmit a torque to idler wheels. A sensor is provided to detect the switching on and switching off of the dog clutch. In case the switching off of the dog clutch is not detected when the rotational speeds of the idler wheels have exceeded a predetermined value after the starting of the vehicle, the electric motor is driven in such a direction of rotation so as to cancel the torque which operates on the dog clutch due to the frictional force in the electric motor.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: December 28, 1999
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kentaro Arai, Tetsuro Hamada, Shigenobu Sekiya
  • Patent number: 5894904
    Abstract: A 4-wheel drive vehicle has a driving force control method in which a portion of a driving force for front wheels is distributed to rear wheels through clutches. In a 4-wheel drive state in which a driving force T.sub.p is distributed to rear wheels, for example, if the vehicle is turned leftwards to generate a difference W.sub.R -W.sub.L between left and right rear wheel speeds, it is ensured that a driving force T.sub.R distributed to the right rear wheel, which is an outer wheel during turning of the vehicle, is larger than a driving force T.sub.L distributed to the left rear wheel, which is an inner wheel during turning of the vehicle, thereby providing an enhancement in turning performance. As the difference W.sub.R -W.sub.L between the left and right rear wheel speeds is increased as a result of decreasing of the turning radius of the vehicle, the driving force T.sub.P (=T.sub.L +T.sub.R) distributed to the rear wheels is decreased to avoid an increase in travel resistance.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: April 20, 1999
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Takayuki Yakou, Koji Kuroda, Tetsuro Hamada, Kazunori Kobayashi, Masayuki Hikita
  • Patent number: 5722305
    Abstract: A gearbox mounted between axles for left and right follower wheels of a vehicle includes a countershaft parallel to the axles. The countershaft is rotated at a speed greater than those of the right axle by speed-increasing gears. The countershaft and the left axle are capable of being connected to each other through first and second shifting gears and a first hydraulic clutch and through third and fourth shifting gears and a second hydraulic clutch. The first and second hydraulic clutches are disposed back-to-back between the first and third shifting gears and therefore, the size of the entire gearbox can be reduced. Moreover, since the first and second hydraulic clutches are mounted on the countershaft which is rotated at the higher speed, the necessary torque transmitting capacities of the first and second hydraulic clutches can be decreased, leading to reduced sizes of the first and second hydraulic clutches.
    Type: Grant
    Filed: September 16, 1996
    Date of Patent: March 3, 1998
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Yasuhiro Sawa, Makoto Nakano, Tetsuro Hamada
  • Patent number: 5221101
    Abstract: A power transmitting system for a four-wheel drive vehicle includes a first hydraulic pump driven interlockingly with the rotation of front wheels, a second hydraulic pump driven interlockingly with the rotation of rear wheels, and a hydraulic clutch for connecting the front wheels and rear wheels. The hydraulic clutch is adapted to be brought into an engaged state by an increase in oil pressure based on the difference between the amount of oil discharged from one of the hydraulic pumps and the amount of oil drawn into the other hydraulic pump. The hydraulic clutch, first hydraulic pump and second hydraulic pump are arranged in that sequence from the front toward rear of the vehicle on an axis extending longitudinally of the vehicle to maximize the air cooling effect on the hydraulic clutch and minimize the length of oil passages between the two hydraulic pumps.
    Type: Grant
    Filed: March 26, 1991
    Date of Patent: June 22, 1993
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kiyokazu Okubo, Tetsuro Hamada, Kazunori Shibuya, Kentaro Arai
  • Patent number: 5219038
    Abstract: A power transmission system for a four-wheel drive vehicle, comprising an engine for directly driving a primary driven axle, and a torque transmission device for transmitting drive torque from the primary driven axle to a secondary driven axle as required, according to a difference in the rotational speed between the front and rear axles, and the torque transmitted between the front and rear axles is reduced for a given difference in the rotational speed between the front and rear axles as a vehicle speed is increased. Thereby, the unnecessary burden of load on the rear axle members is reduced. Preferably, the torque transmission device comprises a structure for limiting the upper limit of the torque which can be transmitted to the secondary driven axle.
    Type: Grant
    Filed: November 14, 1990
    Date of Patent: June 15, 1993
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Kazunori Shibuya, Kentaro Arai
  • Patent number: 5201820
    Abstract: To ensure the benefits of four-wheel drive when the vehicle is accelerating or when the front wheels are slipping, and to eliminate the disadvantage of undesirably transmitting the braking force to the rear wheels when the vehicle is decelerating or when a braking action is applied to the vehicle, the front wheels and the rear wheels are coupled with each other when the rotational speed of the front wheels is higher than that of the rear wheels, but this coupling is disconnected when the rotational speeds of the front and rear wheels are substantially identical or when the rotational speed of the rear wheels is higher than that of the front wheels.
    Type: Grant
    Filed: November 14, 1990
    Date of Patent: April 13, 1993
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Kazunori Shibuya, Kentaro Arai
  • Patent number: 5065836
    Abstract: A motor vehicle such as a four-wheel drive vehicle having a first axle shaft which is driven by a drive source and a second axle shaft which is driven by the same drive source, each of a pair of wheels associated with the second axle shaft being powered by way of individual variable torque transmitting devices, further comprising: a steering condition sensor; and a control unit which reduces a torque transmission ratio of one of the variable torque transmitting devices corresponding to the inner one of the wheels of the second axle shaft when the steering condition sensor has detected a steering angle greater than a prescribed value. Thereby, the problem of the tight turn braking can be avoided without losing the advantages of four-wheel drive.
    Type: Grant
    Filed: April 30, 1990
    Date of Patent: November 19, 1991
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Yoshiki Noro, Noboru Ashikawa
  • Patent number: 5015009
    Abstract: An active suspension system and an active suspension control method for a vehicle having a first wheel set and a second wheel set, comprising a power actuator interposed between the vehicle body and each of the wheels; a sensor for detecting turning maneuver of the vehicle; and a control unit for controlling operation of the actuators according to data obtained from the sensor so as to reduce a vertical load acting on the inner wheel of the second wheel set which bears a less vertical load than the first wheel set during the turning maneuver. Thereby, the shifting of the vertical load between the wheels of the first wheel set is reduced with the result that the overall cornering force of the vehicle is maximized because of the saturating property of the maximum cornering force of the tire in relation with the vertical load acting thereon.
    Type: Grant
    Filed: February 5, 1990
    Date of Patent: May 14, 1991
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Yasuharu Ohyama, Masaki Izawa, Katsuji Watanabe, Tetsuro Hamada
  • Patent number: 5010971
    Abstract: A steering system (1) for vehicles including a front wheel steering mechanism (1a) for steering front wheels (5) at an angle in accordance with a steering operation of a driver, and a rear wheel steering mechanism (1b) for steering rear wheels (11) at an angle (Sr) in accordance with a travelling state of the vehicle.For the steering of the rear wheel, a reference steering angle (Ar) according to a turning state of the vehicle and a corrective steering angle (Ac) according to a velocity derivative thereof are computed, and the steering angle (Sr) of the rear wheel is obtained by making either an addition or a subtraction of the reference and corrective steering angles at least in accordance with the velocity derivative.
    Type: Grant
    Filed: May 3, 1988
    Date of Patent: April 30, 1991
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Shoichi Sano, Yoshimi Furukawa
  • Patent number: 5000522
    Abstract: In a vehicle having a pair of left and right coaxially disposed wheels operatively coupled together via a differential gear which serves to restrict an increase in the difference in rotational speed between the wheels, a method to carry out anti-lock control of both the wheels concurrently during braking operation by utilizing a higher one of the wheel speeds thereof. This enhances braking efficiency and only one control channel is required for the wheels.
    Type: Grant
    Filed: December 19, 1988
    Date of Patent: March 19, 1991
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Shohei Matsuda, Tetsuro Hamada, Makoto Sato
  • Patent number: 4971175
    Abstract: A steering system (1) for vehicles including a front wheel steering mechanism (1a) for steering front wheels (5) at an angle in accordance with a steering operation of a driver, and a rear wheel steering mechanism (1b) for steering rear wheels (11) at an angle (Sr) in accordance with a travelling state of the vehicle. For the steering of the rear wheel, a reference steering angle (Ar) according to a turning state of the vehicle and a corrective steering angle (Ac) according to a velocity derivative thereof are computed, and the steering angle (Sr) of the rear wheel is obtained by making either an addition or a subtraction of the reference and corrective steering angles at least in accordance with the velocity derivative.
    Type: Grant
    Filed: December 21, 1984
    Date of Patent: November 20, 1990
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Shoichi Sano, Yoshimi Furukawa
  • Patent number: 4964481
    Abstract: A steering system for a vehicle with a steerable front wheel (5) and a rear wheel (11) controlled to be steered in accordance with a travelling state representative quantity (.delta..sub.f, V, .alpha..sub.a), wherein the rear wheel is steered taking into account at least a ratio of a cornering power (Kr) thereof to a vertical load on the tire thereof, besides the travelling state representative quantity.
    Type: Grant
    Filed: January 10, 1985
    Date of Patent: October 23, 1990
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Shoichi Sano, Yoshimi Furukawa, Tetsuro Hamada
  • Patent number: 4921065
    Abstract: A motor vehicle such as a four-wheel drive vehicle having a first axle shaft which is driven by a drive source and a second axle shaft which is driven by the same drive source, each of a pair of wheels associated with the second axle shaft being powered by way of individual variable torque transmitting devices, further comprising: a steering condition sensor; and a control unit which reduces a torque transmission ratio of one of the variable torque transmitting devices corresponding to the inner one of the wheels of the second axle shaft when the steering condition sensor has detected a steering angle greater than a prescribed value. Thereby, the problem of the tight turn braking can be avoided without losing the advantages of four-wheel drive.
    Type: Grant
    Filed: March 31, 1988
    Date of Patent: May 1, 1990
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Yoshiki Noro, Noboru Ashikawa
  • Patent number: 4889353
    Abstract: To the end of eliminating the problems arising from substantially rigid connection between a front wheel set and a rear wheel set in a four-wheel drive vehicle, there is provided a power transmission system in which a speed-dependent power transmission device is provided between the front wheel set and the rear wheel set so that both the wheel sets are substantially rigidly connected to each other in a low speed range and rotational power is transmitted only from the front wheel set to the rear wheel set in a high speed range.
    Type: Grant
    Filed: January 27, 1988
    Date of Patent: December 26, 1989
    Assignee: Honda Giken Kogyo K.K.
    Inventors: Tetsuro Hamada, Kazuhiko Shimada, Katsuhiko Masuda, Kazunori Shibuya
  • Patent number: 4886141
    Abstract: In a multi-axle drive vehicle having a first axle which is directly coupled to a power source, and a second axle which is coupled to the power source by way of a coupling such as a viscous coupling which is adapted to transmit torque as a mathematical function of a difference in rotational speed between its input end and output end, to the end of eliminating the problems arising from transmission of braking force between the wheels of difference axles, the vehicle is further provided with a clutch for selectively interrupting transmission of power from the power source to the second axle, a brake sensor for detecting activation of a brake system of the vehicle, and a control unit for activating the clutch when the brake sensor has detected activation of the brake system. The conditions for activating the clutch may further include that the vehicle is running at a high speed which may be detected either directly or from a shift position of the power transmission system of the vehicle.
    Type: Grant
    Filed: June 8, 1988
    Date of Patent: December 12, 1989
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Hiroshi Ikegami, Tetsuji Muto, Tetsuro Hamada, Katsuhiko Masuda, Kazuhiko Shimada, Kazunori Shibuya
  • Patent number: 4878566
    Abstract: A method and mechanism for selectively transmitting and interrupting power between an input shaft and an output shaft arranged in coaxial relation in which a rotary member is coupled to one of the shafts to provide first and second states therebetween and wherein in the first state the rotary member is free to rotate and rotation is transmitted between the input and output shafts, whereas in the second state the input shaft can rotate relative to the output shaft and transmission of rotation is interrupted. The rotary member and the one shaft are angularly rotated relative to one another between first and second relative positions in the first and second states, and rotation of the rotary member is halted by a disc brake in the second state.
    Type: Grant
    Filed: October 23, 1987
    Date of Patent: November 7, 1989
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Tetsuro Hamada, Katsuhiko Masuda, Kazunori Shibuya, Kazuhiko Shimada, Etsuo Fujii, Hiroshi Ikegami, Kunitaka Furuya
  • Patent number: 4848507
    Abstract: To the end of eliminating the problems arising from substantially rigid connection between a front wheel set and a rear wheel set in a four-wheel drive vehicle, there is provided a power transmission system in which a torque-dependent power transmission device is provided between the front wheel set and the rear wheel set so that both the wheel sets are substantially rigidly connected to each other in a low torque range and rotational power is transmitted only from the front wheel set to the rear wheel set in a high torque range. The power transmission device of this kind can be conveniently formed by a parallel combination of a one-way clutch and a torque limiter.
    Type: Grant
    Filed: January 27, 1988
    Date of Patent: July 18, 1989
    Assignee: Honda Giken Kogyo K.K.
    Inventors: Katsuhiko Masuda, Kazuhiko Shimada, Tetsuro Hamada, Kazunori Shibuya
  • Patent number: 4829849
    Abstract: A power transmission system suitable for use in a four-wheel drive motorcar. A torque generated from a power source is directly transmitted to a first axle, and it is transmitted to a second axle via a torque transmission device making use of viscosity of fluid. Between the power source and the second axle is provided torque limiter means for limiting a torque transmitted to the second axle to smaller than a preset value. Even if the torque transmission device should take a locked condition, an excessively large torque would not be exerted upon the respective parts in the power transmission system, and hence a torque transmission system can be made light in weight.
    Type: Grant
    Filed: August 20, 1987
    Date of Patent: May 16, 1989
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Katsuhiko Masuda, Tetsuro Hamada, Kazunori Shibuya, Kazuhiko Shimada