Abstract: Disclosed herein is a card adapter for electrically connecting electrical connecting portions of a card-shaped electronic device such as a CF card to contacts in a slot for a PC card provided in a personal computer. The card adapter 1 includes a chassis 10, a pair of conducting plates 40 provided on the upper and lower sides of the chassis 10, and a grounding member 20, and the like. The grounding member 20 is used to provide an electrical path for electrically connecting a grounding contact portion of the CF card to a grounding part of the slot without using the conducting plates 40 and it is formed into a single part. By using such a grounding member 20, the card adapter 1 can directly connect the grounding contact portion of the CF card to the grounding part of the slot to accomplish stable and reliable grounding.

Abstract: Disclosed herein is a card adapter which can reliably isolate a slot provided in a personal computer and a card-shaped electronic device from a user. The card adapter 1 includes a chassis 10, a pair of conducting plates 70, 71 provided on the upper and lower sides of the chassis 10, and the like. The chassis 10 includes a pair of arms 17L, 17R, and the tip portions of the arms 17L, 17R are provided with a pair of insulating grip portions 18L, 18R, respectively, for insulating the pair of conducting plates 70, 71 from a user. According to such a structure, the card adapter 1 can prevent the possibility that static electricity charged in the body of a user is discharged to the slot or to the card-shaped electronic device connected to the card adapter 1 through conductive parts such as the conducting plates 70, 71 and the like so that electronic circuits provided in the card-shaped electronic device or in the slot are broken or damaged.

Abstract: A protective cover assembly of a gas sensor which is made up of an inner and an outer cover. The inner cover is disposed within the outer cover coaxially through a given clearance. The dimension of the clearance is defined within a range suitable for improving the response rate of the gas sensor while ensuring the effect of avoiding the damage such as cracks in a sensor element arising from wetting thereof with moisture contained in a measurement gas.

Abstract: A miniature connector has an inner insulated body, which supports a plurality of contact conductors which contact conductors on a companion connector, the inner insulating body being surrounded on the outside by a shield case, and an outer surface of a connection cord side end of the shield case is covered by an external insulated mold, adjacent contact conductor housing holes, in which connection ends of the contact conductors are placed, have differing depths, a connecting part cover, formed in unitary manner with the inner insulated body preventing a connection cord core wire, which is soldered onto each of the connection ends, from popping out of its corresponding contact conductor housing hole.

Abstract: A heater control system is provided for controlling the temperature of a heater used to heat a solid electrolyte-made sensing element of a gas concentration sensor up to a given temperature at which the sensing element is activated to provide a desired gas concentration output for controlling a preselected variable used in a given feedback control system. The heater control system controls an electric power supplied to the heater to bring the temperature of the sensing element into agreement with a target temperature value and determines the target temperature value as a function of the preselected variable used in the feedback control system so that only desired quantity of power may be supplied to the heater, thereby minimizing a consumption of the power.

Abstract: A flexibly mounted miniature circuit board moves slightly within an electrical connector preventing electrical failure when subjected to improper forces. The miniature circuit board is electrically connected to an inner connector. The inner connector has a plurality of electrical connectors for connecting to external contacts. The miniature circuit board and inner connector are surrounded by an electrically insulating resin case. The inner connector is rigidly mounted to the insulating case. The miniature circuit board is soldered to the inner connector.

Abstract: Each gas sensing element, with a measured gas sensing electrode and a reference gas sensing electrode provided on opposite surfaces of a solid electrolytic body, is manufactured to have a limit current value whose initial value is offset from a target value. Electric power is supplied to each manufactured gas sensing element to adjust the limit current value from the initial value to the target value.

Abstract: A T-shaped groove is cut out from a section of a guide wall of a memory card connector. The groove also defines an interior T-shaped portion. The bar portion of the interior T-shaped portion is bent back 180 degrees so that it extends over the groove from which it was cut out. The bar portion of the interior T-shaped portion makes contact with the edges of the groove preventing the interior T-shaped portion from moving through the groove. The interior T-shaped portion also has an arcuate portion that resiliently holds a memory card in place. The memory card connector also includes a connection part and at least one other guide wall arraigned to from a U-shaped slot for holding a memory card.

Abstract: An air-fuel ratio sensor generates linear air-fuel ratio detection signals proportional to concentration of oxygen in exhaust gas from an engine in response to a command voltage from a microprocessor. A bias command signal generated by the microprocessor is provided to a D/A converter which converts it to an analog signal. Thereafter, the signal is provided to an LPF for removing the high frequency components of the analog signal. Output voltage of the LPF is provided to a bias control circuit. A single AC signal which has a predetermined frequency and which is provided with a predetermined time constant (about 159 .mu.s) by the LPF is applied to the air-fuel ratio sensor. Element resistance of the air-fuel ratio sensor is detected based on the voltage of the AC signal and the change in the current level of the air-fuel ratio sensor caused by the application of the AC signal.

Abstract: An A/F sensor outputs a linear air-fuel ratio detection signal proportional to the oxygen concentration in an exhaust gas from an engine upon application of a voltage. A computer controls the applied-voltage in a stoichiometric control region, a lean burn control region, an atmosphere detection region and a rich control region to have a fixed value such that the change rate of the applied-voltage is reduced to be less than that in other regions. In addition, when changing the voltage applied to the A/F sensor, the computer variably sets the voltage change speed sequentially. Thus, the influence of the capacitive characteristic of the A/F sensor is eliminated.

Abstract: An A/F sensor is driven by a voltage applied thereto at a command issued by a microprocessor, outputting an A/F detection signal which is linearly proportional to the concentration of oxygen. The microprocessor controls the voltage applied to the A/F sensor to bring a current flowing through the A/F sensor to a predetermined value in a zone outside a predetermined air-fuel ratio detection zone. In this outside zone, the applied voltage is controlled in accordance with a characteristic different from a positive characteristic in a normal positive characteristic in a voltage-current relation. That is, in a rich zone outside the air-fuel ratio detection zone, the applied voltage is controlled so as to make the applied voltage approach a maximum value of the electromotive force of the A/F sensor. In a lean zone outside the air-fuel ratio detection zone, on the other hand, the applied voltage is controlled so as to make the applied voltage approach a minimum value of the electromotive force of the A/F sensor.

Abstract: In an air-fuel ratio control of an engine, an oxygen sensor element is operated with an operating voltage for producing an electric current corresponding to an air-fuel ratio of mixture. The operating voltage is varied in accordance with a range of the air-fuel ratio to be detected, i.e., lean air-fuel ratio, stoichiometric air-fuel ratio or rich air-fuel ratio. The operating voltage may be varied in correspondence to the actual electric current produced from the sensing element or a target value of the air-fuel ratio to which the engine is feedback-controlled.

Abstract: An oxygen sensor has a detecting device unit for outputting a sensor current such as a limiting current of which a value is constant even though a sensing voltage applied to the oxygen sensor changes in a limiting current generating region and corresponds to an air-fuel ratio of a combustion gas and a heater for heating the detecting device unit to keep a resistance of the detecting device unit even though the oxygen sensor is degraded. When the sensing voltage is changed to a second sensing voltage of a resistance governing region, a current peak occurs in the sensor current, and a peak current value is detected. Because the peak current value decreases as the oxygen sensor is gradually degraded, when the peak current value is lower than a degradation judging value, it is judged that the oxygen sensor is degraded. Therefore, the diagnosis of the degradation of the oxygen sensor can be performed with a high accuracy.