Abstract: A float chamber is defined within a body, which is also formed with an inlet passage for supplying fluid into the float chamber, and an outlet passage for taking fluid out from the float chamber opening into a lower part of the float chamber. A float is mounted within the float chamber so as to be movable up and down, and acts on a fluid valve for controlling fluid flow into the float chamber through the intake passage, causing the valve to open and close. The shapes of the float and the float chamber are such that the amount of fluid required to be present in the float chamber in order to float the float at the position in which it just causes the valve to be closed, in equilibrium between its weight and the buoyancy force exerted by the fluid, is independent of the angle of tilting of the float chamber within a certain tilting range.

Abstract: An acceleration pump for a carburetor incorporating first and second pump levers rockably secured to the carburetor body and moved via an acceleration rod connected at one end to the pump lever and a throttle lever connected at one end to the acceleration rod by a throttle valve rockably installed within the barrel of the carburetor, thereby telescopically moving a pump rod secured to a piston of a piston type acceleration pump or to a diaphragm of a diaphragm type acceleration pump. The acceleration pump thus employing the first and second pump levers can obtain an ideal fuel flow curve by increasing the fuel injection time thereof into the air intake opening of the carburetor to improve the exhaust gas purification while improving the drivability and acceleration of a vehicle by preventing a temporarily lean air/fuel ratio of the air/fuel mixture supplied to the carburetor immediately after the acceleration of the vehicle.

Abstract: A diaphragm means for driving a secondary throttle valve in a two-barrel carburetor of the type wherein the secondary throttle valve is opened by a diaphragm means actuated by the venturi vacuum when the primary throttle valve is opened, including an expanding and contracting diaphragm rod, which is normally contracted but which is expanded against a spring face when the secondary throttle is being forcibly held closed during high-speed running, and whose contraction is damped.

Abstract: A float chamber is in communication with the surrounding atmosphere through a valve actuatable in response to a negative pressure in an intake manifold so that when an engine is excessively inclined or upset the valve is closed under the pressure of the fuel in the float chamber. Therefore, the overflow of the fuel into the carburetor barrel may be prevented and a fire in the vehicle avoided.