Abstract: An air-fuel ratio control system for an internal combustion engine having a carburetor with a slow speed circuit, includes a feedback control means by which an air intake side secondary air is supplied to the carburetor, on the downstream side of the throttle valve, in response to a result of detection of air-fuel ratio in terms of the oxygen concentration in the exhaust gas of the engine. Under a predetermined operating condition of the engine, the feedback control of the air-fuel ratio by means of the control of the air intake side secondary air is performed while the supply of the fuel through the slow speed circuit of the fuel supply system is controlled in response to the result of the detection of the air-fuel ratio. In a variation of the system, the supply of the fuel through the slow speed circuit is stopped during the predetermined operating condition of the engine.

Abstract: A secondary air intake system for adding air to the intake of an internal combustion engine includes an air control valve for changing the open area of a secondary air intake passage. The air control valve is opened and closed from a first and second pressure supply means. A first pressure supply means gradually supplies the first and second control pressure to operate the air control valve and open and close the secondary air intake passage in response to an air-fuel ratio signal. The first pressure supply means also supplies the second control pressure independent of the air-fuel ratio signal during a predetermined engine operating state. A second pressure supply means supplies the second control pressure separately of the first pressure supply means during a predetermined engine operating state.

Abstract: In magnetic tape transport system of the type comprising a tape supply reel, a tape take up reel and vacuum columns located on the supply and take up for applying a tension to a magnetic tape, there are provided tape mounting members for removably supporting the take up reel and the supply reel, upright supply and take up vacuum column having openings opened downwardly, said supply and take up vacuum columns being disposed on the right side of and adjacent to the supply and take up reel mounting means their openings directed downwardly, and a capstan and a magnetic head assembly, said supply and take up vacuum columns, said capstan and said magnetic head assembly being disposed on a tape running path from said supply vacuum column to said take up vacuum column. There is also provided an automatic tape threading means between the magnetic head assembly and the take up reel on the tape path.

Abstract: A weighing method and apparatus is provided wherein an excessive amount or number of objects to be weighed over the predetermined or target weight is distributed among a plurality of weighing machines and weighed with combinations of actually measured values being obtained from the plurality of weighing machines and calculated, and the combination of weights which is equal to or most approximates that of the target or predetermined weight is selected.