Abstract: A method and apparatus for cycling a neutral switch of an automated mechanical transmission includes software which, either independently or by operator command through a shift actuator having side-to-side motion capability and sensors, controls a select piston and cylinder assembly to provide shift rail motion along a transverse axis of the transmission which simulates operator commanded motion of a shift rail of a conventional (manual) transmission as the operator checks for neutral. Such activity may release a malfunctioning neutral switch thereby providing a proper neutral indication to associated transmission and engine components to, for example, permit starting of the engine.

Abstract: A method for controlling the speed of internal combustion engines in heavy duty trucks and the like compensates for the overshoot, i.e., the difference between a targeted or commanded engine speed and a transient overspeed or underspeed. The method comprehends executing a program or subroutine where a throttle or engine speed change command is received by a controller, the engine speed change is monitored, a value of overshoot (on both an engine speed increase or decrease) is detected and the detected overshoot is subsequently utilized to temporarily reduce the speed change command, thereby effectively eliminating the overshoot and more positively and quickly arriving at the targeted engine speed.

Abstract: An electrorheological inertia brake for a manual or automated mechanical transmission provides improved control of the speed of input shafts and countershafts during shifts and extends the service life of the transmission. The electrorheological inertia brake includes a housing defining a cavity filled with electrorheological fluid. A shaft coupled to a transmission shaft extends into the cavity and includes vanes, paddles or other drag increasing features. An electric current which may be of variable intensity is passed through the fluid to increase the viscosity, create drag and slow the associated transmission components.

Abstract: The proposal is to compare determined measurement values in the form of the actual engagement position to a set engagement speed of the clutch apparatus with a set position and a set engagement speed so that, upon the attainment of a known set-position and the presence of a defined deviation or a trend toward a diversion in the concept of an over-stepping of the set engagement speed, the set engagement speed of the clutch apparatus is braked to a predetermined engagement speed which prevents an undesired engagement impact of the clutch apparatus or at least alleviates an excessive engagement speed.

Abstract: A master clutch includes a pressure plate adjacent to a friction disc. A centrifugal weight forces the pressure plate and friction disc into engagement when in a desired install position. A locking device retains the centrifugal weight in the desired installed position. A controller sends an electronic command to a system component, such as an engine, to disengage the locking device. In one example, the electronic command may be an engine speed command that is above an engine speed limit in a normal vehicle operating mode. Commanding the engine to run at a speed greater than the typical engine speed limit moves the centrifugal weight out of the desired installed position making the master clutch operational.

Abstract: A method for self configuring automated mechanical transmissions (AMT) and electronic control units (ECU) ensures compatibility therebetween. The method comprehends undertaking a program or subroutine when the vehicle is first powered up which moves the shift operators into a predetermined position. The shift operators include full stroke sensors. Depending upon differences between the commanded shift pattern and the actual shift pattern of the transmission, the specific type of transmission, for example, a twelve speed or a sixteen speed, can be determined.

Abstract: Across the spectrum of automatic transmissions, rapidly depressing the accelerator pedal to floor is interpreted by the transmission and associated components as a request for increased engine power to, for example, pass another vehicle or climb a hill. A method of operating an automated mechanical transmission includes a throttle position sensor and electronic control unit and provides a simulated signal in response to various full throttle positions and travel. Various time and position dependent relationships such as substantially fully depressed throttle, rapidly depressed throttle, throttle maintained substantially fully depressed and throttle substantially fully released before being depressed, i.e., a “pumped” throttle are sensed by the throttle position sensor and interpreted as a throttle kickdown by the electronic control unit which generates a kickdown signal.

Abstract: A vehicle power train system includes an engine, a transmission, and a centrifugal clutch assembly that selectively couples an engine output shaft to a transmission input shaft in response to an operator input. An operator selects a desired vehicle-operating mode by actuating a shift lever or shift switch from a gear selection device. The gear selection device indicates many different operating modes and includes a low-speed maneuvering mode that is selected for low-speed operations such as coupling a truck to a trailer, or positioning a truck and/or trailer in relation to a loading dock area. Once the low-speed maneuvering mode is selected, a control unit controls at least one of engine speed and engine torque to indirectly effect clutch slippage, which results in improved vehicle speed control at low-speed operations.

Abstract: A clutch assembly includes a reaction surface that provides several disengagement surfaces that cause axial movement of a front plate to reduce torque transmission at rotational speeds above an engagement speed. The disengagement surfaces reduce torque to break torque lock at rotational speeds corresponding to desired gear changes. The clutch assembly is controlled to tailor the relationship between clutch torque and engine speed to current vehicle operating conditions to provide consistent vehicle performance over different operating conditions.

Abstract: A centrifugal clutch assembly includes a clutch cover attachable to a rotatable input member. Friction plates are clamped between pressure plates in response to rotation of the clutch assembly. Rotation of the clutch assembly causes at least one centrifugal weight to move radially outward to force the pressure plates against the friction plates. The radial position of the centrifugal weights is modified to tailor clutch actuation. This modification of centrifugal weight position causes a corresponding change to engagement characteristics of the clutch assembly allowing clutch actuation to be tailored to operating conditions.

Abstract: A control for a transmission and a clutch monitors conditions to determine when a vehicle associated with the clutch and transmission is likely in a stationary state. If the vehicle appears to be stationary, with the transmission engaged and the clutch open, then the control determines that the transmission should be moved to a neutral position. Upon movement to the neutral position, the control then closes the clutch. It is preferable for a vehicle remaining stationary to have its clutch closed and its transmission in neutral than to have its transmission engaged and its clutch open. In a further aspect of this invention, the neutral state is verified by testing the ability to move one of the transmission shift components. If the transmission shift component can move beyond a predetermined amount, this is indicative that the transmission is in neutral.

Abstract: An inertia brake assembly for a transmission includes a hollow shaft rotatable relative to an input shaft of the transmission. An inertia brake housing is rotatable relative to the input shaft and the hollow shaft. A first clutch assembly couples the hollow shaft to the inertia brake housing. A second clutch assembly couples the input shaft to the inertia brake housing and a retarder assembly couples the inertia brake housing to the transmission housing. Selective actuation of a combination of the various clutch assemblies provides the functions of an inertia brake, engine brake, hill holder, master clutch and drive a power take-off assembly.

Abstract: A clutch assembly controller monitors initiation points for torque transfer and clutch lockup to determine a clutch engagement rate. Engine output shaft and transmission input shaft speeds are monitored to determine the points at which the torque transfer and clutch lockup begin. These points are stored as reference points and are updated as the clutch wears over time. The clutch engagement rate is also modified over time as the reference points change. Further, the controller utilizes the reference points to approach the desired clutch engagement and disengagement points at a higher rate of speed to optimize responsiveness while automatically changing to a lower rate of speed once operating in the desired region of interest to optimize clutch operating performance and comfort.

Abstract: A centrifugal clutch assembly includes movable centrifugal weight reaction surfaces that provide for actuation at varying rotational speeds. A radially movable front plate with a ramped surface changes the radial position at which the centrifugal weight begins moving the front plate axially to compress a clamp spring and begin clutch actuation. An axially movable back plate moves axially to change the magnitude of compression caused by axial movement of the front plate. The changes to clamping force corresponding to movement of the reaction surfaces of the centrifugal weight change the rotational speed required to beginning and maintain actuation of the clutch assembly.

Abstract: A normally open clutch assembly includes a device holding a centrifugal weight in a position causing axial movement of pressure plates and thereby a clamping force between pressure plates and the friction disks. The clamping force holds the friction disks in a desired aligned position during assembly.

Abstract: A centrifugal clutch assembly includes a sleeve movable to selectively engage the clutch assembly independent of rotational speed. The clutch assembly includes centrifugal weights that move radially responsive to rotation of the clutch assembly. The centrifugal weights move pressure plates between clamped and open positions in response to a desired rotational speed. The sleeve is movable to selectively engage the pressure plate independent of rotational speed of the clutch assembly.

Abstract: A transmission system which relates the relative movement of vehicle components to determine the onset of zero relative torque to permit a shift change to be effected at approximately zero relative torque. When a predetermined signature is identified which relates to the onset of zero relative torque the transmission shift controller initiates a shift.

Abstract: A vehicle transmission system includes a transmission component that has an engaged condition where torque can be transferred from a vehicle engine to a drive component, and a non-engaged condition where torque is prohibited from being transferred to the drive component. A controller generates control signals to control whether the transmission component is in the engaged or non-engaged condition. The controller also identifies when a vehicle start maneuver is a coast start based on vehicle conditions existing just prior to or during the vehicle start maneuver. When a coast start is identified, the controller generates a control signal to either disengage the transmission component or to maintain the transmission component in the non-engaged condition until engine speed generally matches transmission component speed. The controller can directly control engagement by automatically actuating a movable transmission member or can indirectly control engagement by controlling engine speed.

Abstract: A control for a transmission and a clutch monitors conditions to determine when a vehicle associated with the clutch and transmission is likely in a stationary state. If the vehicle appears to be stationary, with the transmission engaged and the clutch open, then the control determines that the transmission should be moved to a neutral position. Upon movement to the neutral position, the control then closes the clutch. It is preferable for a vehicle remaining stationary to have its clutch closed and its transmission in neutral than to have its transmission engaged and its clutch open. In a further aspect of this invention, the neutral state is verified by testing the ability to move of one of the transmission shift components. If the transmission shift component can move beyond a predetermined amount, this is indicative that the transmission is in neutral.

Abstract: The basic warning devices utilized in a vehicle driveline are improved. In particular, should a problem be detected with a clutch or transmission, it is known to actuate a primary warning device. However, the primary warning device itself may be subject to failure. If the primary warning device fails, then an operator of the vehicle may not be provided with an indication of an impending problem in a timely manner. The present invention monitors the operation of each primary warning device, and actuates a secondary warning device should the primary warning device fail. In another portion of this invention, a sensor senses the operation of an automatic clutch for clutch slippage. If clutch slippage occurs, then a warning is sent to the vehicle operator. If the vehicle operator does not take corrective measures, the clutch slippage can continue to occur over time.