Back to results
US 12,723,650 B1Granted
Neutral coast inhibit system and method for transmissions
AssigneeAllison Transmission, Inc.
InventorsLogan Cross, Jeffery Shultz
Life of this patent
Estimating the term…
Abstract
Transmissions and methods of selectively overriding a neutral transmission operating range requested by an operator are disclosed. A transmission includes an input shaft to receive torque from a drive unit, an output shaft to transmit torque to a load, and a control system. The control system includes an output speed sensor to provide an input signal indicative of a rotational speed of the output shaft, a shift selector to provide an input signal indicative of a requested operational range of the transmission, and a controller communicatively coupled to the output speed sensor and the shift selector.
Claims10
A transmission comprising:
- an input shaft to receive torque from a drive unit,
- an output shaft to transmit torque to a load, and
- a control system including an output speed sensor to provide an input signal indicative of a rotational speed of the output shaft, a shift selector to provide an input signal indicative of a requested operational range of the transmission, and a controller communicatively coupled to the output speed sensor and the shift selector, wherein the controller includes a processor and memory having instructions stored therein that are executable by the processor to cause the processor to receive the input signals provided by the output speed sensor and the shift selector, to determine whether the rotational speed of the output shaft is greater than a reference rotational speed based on the input signal provided by the output speed sensor, to determine, in response to a determination that the rotational speed of the output shaft is greater than the reference rotational speed, whether the requested operational range is a neutral range or a reverse range based on the input signal provided by the shift selector, to override, in response to a determination that the requested operational range is a neutral range or a reverse range, the requested operational range with a forward range selection, and to, in response to the determination that the requested operational range is a neutral range or a reverse range, intercept a pulse-width modulation representation of the input signal provided by the shift selector indicative of the requested neutral or reverse range.
A transmission comprising:
- an input shaft to receive torque from a drive unit,
- an output shaft to transmit torque to a load, and
- a control system including an output speed sensor to provide an input signal indicative of a rotational speed of the output shaft, a shift selector to provide an input signal indicative of a requested operational range of the transmission, and a controller communicatively coupled to the output speed sensor and the shift selector,
- wherein:
- the controller includes a processor and memory having instructions stored therein that are executable by the processor to cause the processor to receive the input signals provided by the output speed sensor and the shift selector, to determine whether the rotational speed of the output shaft is greater than 600 rpm based on the input signal provided by the output speed sensor, to, in response to a determination that the rotational speed of the output shaft is not greater than 600 rpm, allow the input signal provided by the shift selector to pass through without being overridden, to determine, in response to allowing the input signal provided by the shift selector to pass through, whether a reverse range was requested in a previous operational state in which a neutral coast inhibit system of the transmission was active, and to, in response to the determination that the rotational speed of the output shaft is greater than 600 rpm, override a requested neutral operational range with a forward range selection based on the input signals provided by the output speed sensor and the shift selector.
2 more elements
A transmission comprising:
- an input shaft to receive torque from a drive unit,
- an output shaft to transmit torque to a load, and
- a control system including an output speed sensor to provide an input signal indicative of a rotational speed of the output shaft, a shift selector to provide an input signal indicative of a requested operational range of the transmission, and a controller communicatively coupled to the output speed sensor and the shift selector,
- wherein:
- the controller includes a processor and memory having instructions stored therein that are executable by the processor to cause the processor to receive the input signals provided by the output speed sensor and the shift selector, to determine whether the rotational speed of the output shaft is greater than a reference rotational speed based on the input signal provided by the output speed sensor, to selectively override a requested operational range with a forward range selection based on the input signals provided by the output speed sensor and the shift selector, to, in response to a determination that the requested operational range is a neutral range, flash “N” on the shift selector when the input signal provided by the shift selector is indicative of the requested neutral range, to, in response to a determination that the rotational speed of the output shaft is not greater than the reference rotational speed, allow the input signal provided by the shift selector to pass through without being overridden, and to determine, in response to allowing the input signal provided by the shift selector to pass through, whether a reverse range was requested in a previous operational state in which a neutral coast inhibit system of the transmission was active.
2 more elements
Dependencies are inferred from the claim text.