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Scott H. Wittkopp

Bio: Scott H. Wittkopp is an academic researcher from General Motors. The author has contributed to research in topics: Clutch & Non-circular gear. The author has an hindex of 24, co-authored 210 publications receiving 2384 citations.


Papers
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Patent
30 Oct 2007
TL;DR: A multi-speed transmission has three planetary gear sets and six torque-transmitting mechanism packaged in various ones of five zones within a transmission cavity as discussed by the authors, each planetary gear set has a ring gear member, a sun gear member and a carrier member that rotatably supports a plurality of pinion gears that intermesh with both the sun gear members and the ring gear members.
Abstract: A multi-speed transmission has three planetary gear sets and six torque-transmitting mechanism packaged in various ones of five zones within a transmission cavity. Each planetary gear set has a ring gear member, a sun gear member and a carrier member that rotatably supports a plurality of pinion gears that intermesh with both the sun gear member and the ring gear member. Certain members are continuously connected for common rotation. Specifically, an interconnecting member continuously interconnects for common rotation the carrier member of the first planetary gear set, the sun gear member of the second planetary gear set and the ring gear member of the third planetary gear set. Additionally, the sun gear member of the first planetary gear set is grounded to the transmission casing via a radially-extending structural member.

349 citations

Patent
13 Mar 2007
TL;DR: In this paper, a controllable selectable one-way clutch is provided for use within a hybrid transmission, which comprises an outer and inner race, and a first and second selector plate.
Abstract: A controllable selectable one-way clutch is provided for use within a hybrid transmission. The clutch comprises an outer and inner race, and a first and second selector plate. A transmission motor controller synchronizes the speeds of the races to facilitate application and release of the clutch, and a transmission controller communicates a signal to the clutch for re-positioning of the plates to apply and release the clutch. The clutch has three operational modes, including freewheeling and holding torque in one direction or both directions. A method is also provided for applying a selectable one-way clutch in a vehicle having a hybrid transmission with a motor controller and a transmission controller, including synchronizing the clutch speed using the motor controller, detecting the direction of the race speed difference, communicating the race speed difference to the transmission controller, and selecting between the clutch operational modes in response to the detected speed difference.

134 citations

Patent
01 May 2007
TL;DR: In this article, a selectable one-way rocker clutch assembly with an inner race disposed radially within an outer race, first and second plurality of rockers, a selector ring and an apply plate is presented.
Abstract: The present invention provides a selectable one-way rocker clutch assembly having an inner race disposed radially within an outer race, first and second plurality of rockers, a selector ring and an apply plate. The inner race defines a plurality of pockets configured to operatively retain the first and second plurality of rockers. The first plurality of rockers is configured to resist rotation of the outer race relative to the inner race in a first direction. The second plurality of rockers is configured to resist rotation of the outer race relative to the inner race in a second direction. The selector ring is disposed radially between the inner race and outer race. The apply plate is configured to engage with the selector ring and, in so doing, rotate the selector ring to thereby selectively retract the first and/or second plurality of rockers and thus control the state of the rocker clutch assembly.

90 citations

Patent
09 Jul 2007
TL;DR: In this paper, the authors present a transmission with a plurality of members that can be utilized in powertrains to provide nine forward speed ratios and one reverse speed ratio, and the transmission includes four planetary gear sets, six torque-transmitting devices, and four fixed interconnections.
Abstract: The transmission has a plurality of members that can be utilized in powertrains to provide nine forward speed ratios and one reverse speed ratio. The transmission includes four planetary gear sets, six torque-transmitting devices, and four fixed interconnections. The powertrain includes an engine and torque converter that is continuously connected to one of the planetary gear members and an output member that is continuously connected with another one of the planetary gear members. The six torque-transmitting devices provide interconnections between various gear members, and the transmission housing, and are operated in combinations of three to establish nine forward speed ratios and one reverse speed ratio.

84 citations

Patent
16 Dec 2003
TL;DR: In this paper, a multi-speed transmission with a selectable braking one-way clutch operative to brake rotation of a member of a planetary gear set of the transmission when the transmission is in reverse and first speed.
Abstract: A multi-speed transmission is provided with a selectable (reversible) braking one-way clutch operative to brake rotation of a member of a planetary gear set of the transmission when the transmission is in reverse and first speed. First and second rotating input clutches are slipped when the vehicle is launched in reverse or first speed. The transmission is preferably characterized by the absence of a torque converter, but the invention may be implemented with a torque converter if desired.

79 citations


Cited by
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Patent
03 May 2010
TL;DR: In this paper, a vehicle control system comprises a sensor controller for taking in sensor signals indicating a status variable of a vehicle and an operation amount applied from a driver, a command controller for generating a control target value based on the sensor signals taken in by the sensor controller, and an actuator controller for receiving the controller target value from the command controller and operating an actuators to control the vehicle, those three controllers being interconnected via a network.
Abstract: A vehicle control system which can ensure high reliability, real-time processing, and expandability with a simplified ECU configuration and a low cost by backing up an error through coordination in the entire system without increasing a degree of redundancy of individual controllers beyond the least necessary level. The vehicle control system comprises a sensor controller for taking in sensor signals indicating a status variable of a vehicle and an operation amount applied from a driver, a command controller for generating a control target value based on the sensor signals taken in by the sensor controller, and an actuator controller for receiving the control target value from the command controller and operating an actuator to control the vehicle, those three controller being interconnected via a network. The actuator controller includes a control target value generating unit for generating a control target value based on the sensor signals taken in by the sensor controller and received by the actuator controller via the network when the control target value generated by the command controller is abnormal, and controls the actuator in accordance with the control target value generated by the control target value generating unit.

383 citations

Patent
30 Oct 2007
TL;DR: A multi-speed transmission has three planetary gear sets and six torque-transmitting mechanism packaged in various ones of five zones within a transmission cavity as discussed by the authors, each planetary gear set has a ring gear member, a sun gear member and a carrier member that rotatably supports a plurality of pinion gears that intermesh with both the sun gear members and the ring gear members.
Abstract: A multi-speed transmission has three planetary gear sets and six torque-transmitting mechanism packaged in various ones of five zones within a transmission cavity. Each planetary gear set has a ring gear member, a sun gear member and a carrier member that rotatably supports a plurality of pinion gears that intermesh with both the sun gear member and the ring gear member. Certain members are continuously connected for common rotation. Specifically, an interconnecting member continuously interconnects for common rotation the carrier member of the first planetary gear set, the sun gear member of the second planetary gear set and the ring gear member of the third planetary gear set. Additionally, the sun gear member of the first planetary gear set is grounded to the transmission casing via a radially-extending structural member.

349 citations

Patent
13 Mar 2007
TL;DR: In this paper, a controllable selectable one-way clutch is provided for use within a hybrid transmission, which comprises an outer and inner race, and a first and second selector plate.
Abstract: A controllable selectable one-way clutch is provided for use within a hybrid transmission. The clutch comprises an outer and inner race, and a first and second selector plate. A transmission motor controller synchronizes the speeds of the races to facilitate application and release of the clutch, and a transmission controller communicates a signal to the clutch for re-positioning of the plates to apply and release the clutch. The clutch has three operational modes, including freewheeling and holding torque in one direction or both directions. A method is also provided for applying a selectable one-way clutch in a vehicle having a hybrid transmission with a motor controller and a transmission controller, including synchronizing the clutch speed using the motor controller, detecting the direction of the race speed difference, communicating the race speed difference to the transmission controller, and selecting between the clutch operational modes in response to the detected speed difference.

134 citations

Patent
02 May 2003
TL;DR: In this article, a multi-stage transmission with an input shaft (3), which is connected to a shiftable front-mounted planet gear set (10), with an output shaft (4), connected to the shiftable main planet gear sets (20), and with a number of shifting elements (A to F) whose selective closing enables the shifting of at least six forward speeds without range shift is described.
Abstract: The invention relates to a multi-stage transmission provided with an input shaft (3), which is connected to a shiftable front-mounted planet gear set (10), with an output shaft (4), which is connected to a shiftable main planet gear set (20), and with a number of shifting elements (A to F) whose selective closing enables the shifting of at least six forward speeds without range shift. An output element of the front-mounted planet gear set (10) can be connected to a first input element of the main planet gear set (20) via a first shifting element (A) and can be connected to a second input element of the main planet gear set (20) via a second shifting element (B). The input shaft (3) can be connected to a third input element of the main planet gear set (20) via a fifth shifting element (E). Preferably, a sun gear (11) of the front-mounted planet gear set (10) can be fixed via a sixth shifting element (F) mounted on the side of the front-mounted planet gear set (10) facing away from the main planet gear set (20). The front-mounted planet gear set (10) is provided in the form of a Plus gearing having inner and outer planet gears (12, 13) whose webs (15, 16) are interconnected.

128 citations

Patent
24 Sep 2008
TL;DR: In this paper, a powertrain system includes an engine mechanically coupled to an electro-mechanical transmission selectively operating in one of a plurality of transmission operating range states and engine states.
Abstract: A powertrain system includes an engine mechanically coupled to an electro-mechanical transmission selectively operative in one of a plurality of transmission operating range states and one of a plurality of engine states. A method for controlling the powertrain system includes determining a current transmission operating range state and engine state, determining at least one potential transmission operating range state and engine state, providing an operator torque request, determining preferability factors associated with the current transmission operating range state and engine state, and potential transmission operating range states and engine states, preferentially weighting the preferability factors for the current transmission operating range state and engine state, and selectively commanding changing the current transmission operating range state and engine state based upon the preferability factors and the operator torque request.

122 citations