GB499395A - Improvements in or relating to boost controls for internal combustion engines - Google Patents

Abstract

499,395. Fluid pressure servomotor control systems. SOC. GENERALE DES CARBURATEURS ZENITH. April 20, 1937, No. 11317. Convention date, April 22, 1936. [Class 135] In a supercharged aircraft engine wherein the amount of air or mixture supplied is controlled both by a lever, (not shown), operated by the pilot and the movement of which in the direction of increasing the amount of air or mixture is limited by a stop, and by a servomotor, (not shown), the valve 24, Fig. 3, controlling the servo is connected to an intermediate point of a floating lever 44, one end of which is connected to a closed expansible capsule 33 arranged in a chamber 35 to which induction pressure is communicated through a pipe 37, while the other end of the lever is connected to a closed expansible capsule 34 arranged in a chamber 36 open to the atmosphere through a pipe 39, the arrangement being such that the maximum permissible induction pressure either increases or decreases as the altitude increases. The servo may control an auxiliary throttle valve or may modify the action of the pilot's control lever on the main throttle, or may actuate the control member of a variable-delivery or variablespeed supercharger. Alternatively, the two capsules may act directly, or indirectly through levers, on the two ends of the valve 24, or, as shown in Fig. 6, the two capsules 33 and 34 may be arranged in series to act directly on one end of the valve. Induction pressure may be supplied to the interior of the capsule 34, or the latter may be replaced by a piston, one side of which is subjected to atmospheric pressure while the other side is subjected to induction pressure. Specifications 358,289, [Group XXVII], and 456,975 are referred to. The Specification as open to inspection under Sect. 91 comprises also an arrangement in which the valve 24, Fig. 10 (Cancelled), is actuated by a single closed capsule 66 arranged in a chamber 65 to which induction pressure is supplied through a pipe 72 provided with a restriction 67 and which is in communication with the atmosphere through a pipe 68 provided with a restriction 69. A spring-loaded valve 70 prevents flow through the pipe 68 into the chamber 65. This subject-matter does not appear in the Specification as accepted.