Abstract: A throttle body for an internal-combustion engine having a hollow venturi member positioned within the body. The member has a first portion projecting out of the body at its intake end, and a second portion positioned generally centrally within the body air duct upstream from a throttle plate. The second portion has an exterior surface spaced inward from the body interior sidewall to form an annular venturi passage therebetween. The first and second portions define an enclosed air channel. Circumferentially distributed entry openings in the first portion open exterior of the body duct for entry of air into the channel, and circumferentially distributed exit openings in the second portion communicating with the venturi air passage for the exit of air from the channel. The channel and the entry and exit openings define a sample flow path of air from a location exterior of the duct to a location adjacent to the venturi passage representative of the air mass flow through the duct.

Abstract: A control system for internal combustion engines, including a first conduit for the flow of intake air, and a second conduit for the flow of natural gas to be mixed with the air for combustion. The flow of the air is variable over a range of mass flow rates during operation of the engine and an air mass sensor is positioned to sense the mass flow rate in the first conduit and generate a first flow rate signal indicating the mass flow rate. A natural gas mass sensor is positioned to sense the mass flow rate of the gas in the second conduit and to generate a second flow rate signal indicating the mass flow rate of the natural gas. The first and second flow rate signals are compared in an electronic controller that generates a control signal if the first and second flow rates vary from a predetermined ratio. The ratio is selected to provide a substantially stoichiometric ratio of air and natural gas.

Abstract: An apparatus and method for use in the attachment of a length of resistive wire under a preselected tension to wire-supporting end portions of a pair of generally parallel, resilient posts attached to a post support member.