BorgWarner has been granted a patent for methods and controllers that reduce noise, vibration, and harshness (NVH) during transmission shifts. The patent describes techniques for determining a target engine speed and torque, as well as adjusting the firing fraction or induction ratio, to achieve a smooth transition during gear changes. These methods are particularly useful for engines operating in skip fire or cylinder output modulation modes. GlobalData’s report on BorgWarner gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on BorgWarner, turbocharger bearings was a key innovation area identified from patents. BorgWarner's grant share as of June 2023 was 1%. Grant share is based on the ratio of number of grants to total number of patents.
Controlling engine speed during transmission gear changes
A recently granted patent (Publication Number: US11685380B1) describes a method for managing a powertrain with an internal combustion engine and a transmission during gear changes. The method involves receiving an indication of a proposed gear change and determining a target engine speed suitable for the new gear. The method also includes determining a target firing fraction or induction ratio to adjust the engine speed and power output, and directing a change to the firing fraction or induction ratio if necessary. The engine speed is then adjusted to the target engine speed.
The method can be performed during skip fire operation of the engine, where certain cylinders are deactivated to improve fuel efficiency. The change to the firing fraction or induction ratio occurs before the shift to the new gear is completed. The target firing fraction or induction ratio is determined based on a pre-calculated lookup table that takes into account the current gear and the proposed gear. Additional factors such as the current engine speed and thermal management may also be considered.
The target engine speed is calculated based on the current vehicle speed, gear ratio, and the new gear. The method differentiates between up-shifts and downshifts, with the induction ratio determined to decelerate the engine for up-shifts and the firing fraction determined to accelerate the engine for downshifts.
The patent also describes a powertrain control system that includes a transmission control unit and an engine control unit. The transmission control unit generates a proposed gear change signal and controls the gear shifts, while the engine control unit determines the target engine speed and whether the current firing fraction is suitable for the new gear. If necessary, the engine control unit directs a change to the firing fraction or induction ratio before the gear shift is completed, and adjusts the engine speed accordingly.
Overall, this patent presents a method and system for effectively managing powertrain operations during gear changes, optimizing engine speed and power output for improved performance and efficiency.