Zf Meritor, LLC

Meritor Transmission Corporation

Zf Friedrichshafen Ag

James Henry Devore

Robert Anthony Sayman

Ronald Peter Muetzel

Muneer Abusamra

Karl-Fritz Heinzelmann

Charles E Allen, Jr

Winfried Sturmer

Ludger Ronge

Loren Christopher Dreier

Mario Steinborn

Rupert Kramer

Jon M Huber

Ronald Muetzel

Rudolf Kalthoff

Gerhard Bockmann

Andreas Bohm

Anthony Robert Sayman

A vehicle driveline control system includes monitoring when the transmission is in gear and the clutch is left open. If that condition exists for a selected amount of time, the controller provides an indication to the driver regarding the open clutch status. In one example, the controller alters the RPM rate of the engine to provide audible feedback to the driver. For example, the controller raises the engine RPM rate from an idle rate to a higher rate to simulate what the driver hears upon vehicle launch. A variety of indicators and control strategies may be used with a system designed according to this invention.

Vehicle driveline control including open clutch indicator

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.

Variable engagement centrifugal clutch assembly

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.

Multi-function centrifugal clutch

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.

Dynamic modification of centrifugal clutch

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.

Method and assembly for controlling a centrifugal clutch

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.

Method of timed shift to neutral in apparent stationary modes

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.

Normally open clutch assembly device

The inventive transmission has at least two different shift modes for shifting between the same two gear ratios. A control unit electronically senses various vehicle conditions and based on this information selects the appropriate shift mode suited for the particular driving situation. The transmission then shifts from one gear ratio to another based on this selection.

Adaptive shift sequencing

A strategy for overcoming a tooth butt condition includes changing a target closed clutch position over time. When a tooth butt condition exists, a controller selectively closes a clutch to provide limited engagement between the engine and the transmission. A first target closed clutch position is used on the first attempt. If the tooth butt condition is not resolved, the controller then changes the target closed clutch position to provide a different level of engagement between the engine and the transmission. This process is repeated until the tooth butt condition is resolved, a preselected period of time expires, a maximum number of attempts has been completed or the maximum desirable closed clutch position has been used.

Clutch control for overcoming tooth butt

A system and method of controlling an automatic clutch to prevent a motor vehicle engine from stalling is disclosed. The method includes the steps of determining an engine stall threshold, detecting accelerator pedal actuation, detecting current engine speed, and comparing current engine speed to the engine stall threshold. If the engine speed is below the engine stall threshold, a controller detects and compares vehicle acceleration to predetermined threshold acceleration such that the automatic clutch is actuated only when the vehicle acceleration is below the threshold acceleration. The system includes the step of detecting foot brake position such that the automatic clutch is only actuated if the foot brake is properly actuated. The controller will then actuate the automatic clutch to proportionally decouple the engine from the transmission to prevent engine stall. The automatic clutch will remain open until detecting a predetermined clearing condition.

Method of preventing engine stall using automated clutch control

A method of engaging and disengaging transmission gears in a vehicle is provided. A controller processes an initial torque representing an engine torque and an estimated zero torque representing an estimate of a transmission output shaft torque. The controller also sets a high and low band torque about the estimated zero torque. Once the above torques have been determined, the controller compares the initial torque to the high band torque. If the initial torque is below the high band torque, the controller increases the engine torque to the high band torque. If the initial torque is greater than the high band torque, then no preliminary adjustments to the engine torque need be made. At least one shift valve is energized when the engine torque is equal to or greater than the high band torque. The engine torque is decayed by the controller to the low band torque to facilitate engaging and disengaging transmission gears.

Growing community of inventors

Laurinburg, NC, United States of America

James Henry Devore