摘要:
To supervise a program controlled device which is subject to stray noise or disturbance pulses, particularly microprocessor controlled automotive vehicle electronic systems, a timing circuit is provided responsive to check pulses added to the program and defining a timing interval, the monitoring system distinguishing between disturbance pulses and static defects by supervising the control pulses and, upon failure of the control pulses, generating a program restart or interrupt signal, respectively, which both initiate a new start of the program cycle or, respectively, define a timing interval which, upon failure to sense further control pulses, initiates energization of an emergency switching system. Continuous failure to receive control pulses also can initiate the emergency switching system. To permit start-up, and before control pulses are obtained, a time delay circuit is provided which disables the monitoring system upon switching ON of the program controlled device at least for the time period of one check pulse cycle.
摘要:
A disk mounted on a rotating shaft of an internal combustion engine has a signal generating segment which causes generation of a pickup signal having a leading and a trailing edge. The two different edges control different processes, as for example ignition processes of different ignition coils, fuel injection processes, or ignition processes during normal and starting operation. A basic counting value is counted down between two sequential edge signals in a counter. This is a speed-dependent value from which different countdown values for the next cycle are computed. To allow adjustment of the angle at which one process takes place without simultaneous adjustment of the angle at which the other process takes place, one or both of the edges of the segment from which the control signals are derived have slanted portions, so that movement of the pickup relative to the slanted portions will effectively cause a change in the angle at which a process is initiated.
摘要:
In order to permit a simplification of the crankshaft rotation sensor device which provides the computer of the control system with angular speed and position information for ignition and/or fuel injection timing, a signal generated by one pickup for every two engine cylinders from a single reference mark on the crankshaft is formed into a signal pulse which is used to trigger the counting of clock pulses from a clock into a counter. These are then periodically transferred to a computer as a numerical signal which represents the required information. In a first mode the counts are transferred every other period between pulses and the counter counts in the cycle periods between the pulses in which the counter is not transferring to the computer. In a second mode, the counter counts every cycle between pulses and the counts are transferred during every pulse itself. There is also described a system which includes additional circuitry by which below a certain speed of the engine the system operates in the first mode and above that speed operates in the second mode.
摘要:
In an ignition system for an internal combustion engine, a digital system for computing the timing advance is provided. Constants approximating the curve of timing advance v. engine speed are stored in a microprocessor. The positive half waves of primary current in the magneto generate the ignition energy and also generate a reference signal for controlling the actual ignition time. The sequence of reference signals is also used to generate a digital value indicative of engine speed. The latter is used to address the read only memory in which the constants for approximating the timing advance curve are stored. After each reference signal, the value read out from the read only memory is counted down by a counter. When the counter reaches the value of zero, ignition is started.
摘要:
An additional diode is provided in series with the charging diode through which the storage capacitor of a magneto ignition system is charged and the shutdown switch for the engine is connected between the common connection of the two diodes and the common connection of the magneto generator, and the capacitor diodes, because of their high back resistance, prevent any high positive or negative voltages from appearing across an open shutdown switch.
摘要:
By means of an auxiliary voltage the semi-conductor controlled rectifier of a capacitor discharge magneto ignition system is at some limiting speed of the engine kept in its conducting condition from a time before the initiation of a charging halfwave until at least after the end of the charging halfwave. The auxiliary voltage is derived from a halfwave of polarity opposite to that which charges the ignition capacitor, and acts through a transistor to keep the SCR continuously conducting while the overspeed condition continues. The overspeed limit will be determined by the bias applied to the transistor.
摘要:
A plurality of receivers which can be respectively addressed by addressing pulses provide reply pulses on a separate reply signal bus indicative of a single digit, or multi-digit binary response condition. To permit extended indication, the central station includes a holding stage which holds the output received from the reply receivers for the duration of a selection cycle during which the plurality of loads can be addressed, for example during a predetermined counted number of such cycles or during a predetermined counted number of pulses to permit averaging-type instruments to respond to said number of pulses --if present--or to permit extended indication of single digit binary output--if present.
摘要:
Clock pulses are counted to provide a count indicative of speed in a counter that is reset with every revolution of a reference mark. The difference between successive counts is multiplied by a fractional factor, which is not necessarily the same for acceleration and deceleration, then added algebraically to the current count value. The acceleration-corrected speed value is then multiplied by a parameter-dependent digital value obtained from a summing circuit to which various engine condition parameters are supplied and the output of the last-mentioned multiplier is supplied to a comparator to which the current count of clock pulses beginning with the reference mark passage is compared. When the comparator finds the match, spark ignition takes place. Another counter counts the clock pulses following each reference mark for sequencing multiplexers that enable some components to serve in more than one operation, in effect controlling the flow of digital values around various loops in the circuit.
摘要:
In order to mount the control circuit for the ignition system at a location remote from the spark plug and ignition coil, i.e. at a location not subject to electromagnetic or electrical interference, photoconductors are used to interconnect the control circuit with the final output stage. Photoconductors are also used to interconnect the basic synchronization unit, that is the unit which furnishes a pulse for each rotation of a shaft of the engine, to the input of the control circuit. A theft prevention device is also incorporated. Specifically, the control circuit compares a sequence stored in a microprocessor to the on/off pattern of a received light pulse sequence. The latter is applied from a light emitter through a convex lens and a photoconductor to a second input of the control unit. Only if the stored pattern corresponds to the received light pattern can control signals initiating a spark be generated.
摘要:
A commutator-type d-c motor has its line current connected through a sensing resistor (18) or transformer (18'), the pulses of which, upon energization, are counted in a counter (C) and also passed to a speed sensing circuit (S) in a control circuit (30), energization of the motor being disconnected if the frequency of undulations or waviness of the motor current drops, thus indicating that the positioned element, for example an antenna, window, or sliding roof of an automobile has reached a limiting position. The counter can be used to establish intermediate positions, upon suitable control by a selector switch (27) or a reference count number stage (C-Ref) controlled, for example, by a potentiometer (P) or from the selector switch (27). A timing circuit (T) prevents short-circuit through the motor upon manual sudden reversal of command of direction of rotation. The main switch can be coupled to a car radio to extend the car radio antenna upon energization thereof, retract the antenna upon de-energization, the selector switch also permitting manual retraction or projection, and disabling of the system if, for example, the radio is used for stored, e.g. tape reproduction.