From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Typed explanation of a vacuum-based fuel feed and intake manifold system, page 2.
| Identifier | ExFiles\Box 40\3\ Scan005 | |
| Date | 2nd March 1921 guessed | |
| Packard MOTOR CAR COMPANY Foglio N° 2 The socket 9 is connected with the intake manifold and has a wider diameter than the small pipe 8 which has a very narrow one. Generally the cover 12 is shut, that means in position to prevent air entrance through the holes 12 and 13. When lack of suction happens in the pipe 1, the car driver presses on the accelerator and opens in the same time the throttle valve 1, located in the above mentioned intake manifold; at the meantime and through the same operation: having a mechanical engagement between the throttle 17 and the pin 16 of the plate 14, same will be so displaced to have the holes 13 corresponding with the holes 12 of the cover 11 of the trun pot 10. At that time small air current will be suct by the motor through the pipe 19. During the depression time an increase of suction will happen in the intake manifold 19 as much as in the reduced pipe 8 of the vacuum tank 5. That will make easier for the burning mixture to come from the carburetor to the motor, but principal matter, the suction increased in that way will be sufficent to suct the petrol from main tank 7 to the vacuum feed 5? The liquid will then fall to the carburetor by gravity. The result is to increase 100/100 the suction existing without the nipple, and I warrant it is more than sufficent to prevent all the troubles presented by all different vacuum tanks on the market. I have also been able to use that nipple keeping the air holes constantly open, without hurting the motor when reuning at a small revolution number; in the opposit case, when the throttle is completely open the power of the motor has tendency to increase. ================== | ||