Engine starting strategy to avoid resonant frequency
AssigneeCaterpillar Inc.
InventorsTimothy M. O'Donnell, Evan E. Jacobson
Life of this patent
Estimating the term…
Abstract
A machine comprising a clutch, an engine operable at a resonant frequency engine speed, and a hybrid motor. The hybrid motor is connected to the engine through the clutch. The hybrid motor applies power to the engine when the clutch is engaged, and does not apply power to the engine when the clutch is disengaged. The hybrid motor is operable at a predetermined hybrid motor speed. An ignition switch starts the hybrid motor. An electronic control module disengages the clutch until the hybrid motor speed exceeds the predetermined hybrid motor speed, and engages the clutch after the hybrid motor speed exceeds the predetermined hybrid motor speed.
Claims18
A machine comprising:
- a clutch adapted to engage and to disengage;
- an engine operable at various engine speeds including a resonant frequency engine speed;
- a hybrid motor selectively operatively connected to the engine through the clutch, the hybrid motor is adapted to apply power to the engine when the clutch is engaged, and the hybrid motor is adapted to not apply power to the engine when the clutch is disengaged, the hybrid motor operable at various hybrid motor speeds including a predetermined hybrid motor speed that is sufficient to power the engine to an engine speed that exceeds the resonant frequency engine speed;
- an ignition switch operatively associated with the hybrid motor, such that the ignition switch is adapted to start the hybrid motor;
- and
- an electronic control module configured to control the clutch to disengage until such time as the hybrid motor speed exceeds the predetermined hybrid motor speed, and to engage to allow the hybrid motor to apply power to the engine at a time after the hybrid motor speed exceeds the predetermined hybrid motor speed.
A method of starting an machine, the method comprising the steps of:
- providing an engine operable at various engine speeds including a resonant frequency engine speed;
- providing a hybrid motor operable at various hybrid motor speeds including a predetermined hybrid motor speed that is sufficient to power the engine to an engine speed that exceeds the resonant frequency engine speed;
- operatively connecting the hybrid motor to the engine through a clutch, the hybrid motor being adapted to apply power to the engine when the clutch is engaged and not adapted to apply power to the engine when the clutch is disengaged;
- disengaging the clutch when the hybrid motor speed is less than the predetermined hybrid motor speed;
- and
- engaging the clutch after the hybrid motor exceeds the predetermined hybrid motor speed.
A method of starting a machine, the method comprising the steps of:
- providing a clutch adapted to engage and to disengage;
- providing a hybrid motor operable at various hybrid motor speeds;
- operatively associating an ignition switch with the hybrid motor;
- operatively associating an electronic control module with the clutch and the hybrid motor, the electronic control module configured to control the clutch to engage and disengage;
- operatively connecting an engine to the hybrid motor through the clutch, such that the hybrid motor is adapted to apply power to the engine when the clutch is engaged and the hybrid motor is not adapted to apply power to the engine when the clutch is disengaged;
- starting the hybrid motor when the ignition switch is triggered;
- controlling the clutch to disengage when the ignition switch is triggered;
- and
- controlling the clutch to engage after the hybrid motor exceeds a predetermined hybrid motor speed that is sufficient to power the engine to an engine speed that exceeds a resonant frequency engine speed.
Dependencies are inferred from the claim text.