Abstract: A shock absorber including a main housing body having a cylindrical portion and closure portions closing the open ends of the cylindrical portion, an inner cylindrical member disposed within the main body and cooperating therewith to define an inner cylinder chamber and an outer annular space, and a piston slidably received within the cylinder chamber, so as to divide the cylinder chamber into two fluid chambers filled with an electro-viscous fluid. The fluid chambers communicate with each other through communication passage which includes a portion formed within the annular space. An operating and a balancing rod are secured to the piston and extend slidably through the respective two closure portions of the main body. The shock absorber includes at least one pair of electrodes one of which consists of a portion of the cylindrical portion of the main body and the other of which consists of a portion of the inner cylindrical portion.

Abstract: In a double air-fuel ratio sensor system including two air-fuel ratio sensors upstream and downstream of a catalyst converter provided in an exhaust passage, the actual air-fuel ratio is adjusted in accordance with an air-fuel ratio correction amount calculated by using the output of the upstream-side air-fuel ratio sensor and an air-fuel ratio feedback control parameter such as delay time periods, skip amounts, or integration amounts calculated by using the output of the downstream-side air-fuel ratio sensor, and the calculation of the air-fuel ratio feedback control parameter is prohibited when the downstream-side air-fuel ratio sensor is in an abnormal state.

Abstract: A combustion process sensor for detecting combustion processes occurring in a combustion chamber of an engine has a generally tubular mounting casing to be screwed into a threaded hole in the combustion chamber wall and a quartz-glass rod axially extending in the mounting casing and held in position therein. The casing includes two axially aligned generally tubular members rigidly secured together at their own ends. The quartz-glass rod has a first portion remote from a sensing end thereof adapted to be exposed to combustion flame in the combustion chamber, and a second portion between the first portion and the sensing end. The first portion is secured to one of the two tubular members of the casing, while the second portion is supported from the casing only by a vibration damping material disposed in engagement with the outer peripheral surface of the quartz-glass rod and the inner peripheral surface of the casing.

Abstract: An exhaust system for multi-cylinder internal combustion engines, which is directed to the so-called proportional exhaust gas recirculation (EGR) for improving engine exhausts. The system comprises an exhaust gas recirculating circuit connected to one engine cylinder for recirculating to an intake pipe of the engine the entire amount of exhaust gas which is discharged from said one engine cylinder. Switching means is provided in said exhaust gas recirculating circuit for switching the flow of the recirculating exhaust gas in response to a value of a predetermined parameter indicating particular operating conditions of said engine.

Abstract: In a double air-fuel ratio sensor system including two air-fuel ratio sensors upstream and downstream of a catalyst converter provided in an exhaust passage, the actual air-fuel ratio is adjusted in accordance with an air-fuel ratio correction amount calculated by using the output of the upstream-side air-fuel ratio sensor and an air-fuel ratio feedback control parameter such as delay time periods, skip amounts, or integration amounts calculated by using the output of the downstream-side air-fuel ratio sensor, and the calculation of the air-fuel ratio feedback control parameter is prohibited when the downstream-side air-fuel ratio sensor is in an abnormal state.