The Jake Brake permits large trucks to descend long, steep grades at a controlled speed. It was the first practical mechanism for altering on demand the valve timing on a truck diesel engine, thereby converting the engine to a power absorbing machine. The modified engine can continue to power the truck in normal operation, allowing service brakes to remain cool for emergency situations. Invented by Clessie Lyle Cummins (1886-1968), this device (produced by the Jacobs manufacturing company since 1961) has contributed significantly to highway safety.
Jake Brake
![](/sites/default/files/styles/landmark_node_/public/landmarks/images/Jake_Brake.jpg?itok=M7tIP5IX)
YearAdded:
Image Credit: Courtesy Wikipedia/Sierra Fournier (CC BY-SA 3.0)Image Caption: Jacobs Engine Brake Retarder ("Jake Brake")Era_date_from: 1957
1985
Innovations
![](/sites/default/files/styles/thumbnail/public/landmarks/images/Jake_Brake.jpg?itok=_36eUPIb)
The Jake Brake permits large trucks to descend long, steep grades at a controlled speed. It was the first practical mechanism for altering on demand the valve timing on a truck diesel engine, thereby converting the engine to a power absorbing machine. The modified engine can continue to power the… Read More