Abstract:
A trouble monitor device for a bridge circuit which can reliably detect any trouble of a bridge circuit even when multiple troubles occur in a sensor circuit utilizing the bridge circuit. The change of an unbalanced output signal of the bridge circuit is monitored by a first window comparator (WC1) and the undesirable change of a power supply current for amplifying the bridge circuit (11) is monitored by a second window comparator (WC2) so that an output having a logical value "1" representing normality of the bridge circuit can be generated from an AND gate (13) when both monitor outputs are a logical value "1" representing normality.
Abstract:
A fail-safe scanning circuit having a scanning output generating circuit (20) for generating continuously scanning output signals which are given to objects to be driven, and a failure sensing circuit (30) for sensing whether the scanning output state of the circuit (20) is normal or not. When an abnormality of the scanning output of the circuit (20) is sensed, the output of the failure sensing circuit (30) is made to stop. Also, using two such fail-safe scanning circuits (41, 42), a pair of a light emitting element and a light receiving element are driven to scan synchronously. Thereby, a sensor of a multi-optical-axis beam type is obtained as a fail-safe man-sensor in a system wherein machines and men work in the same space.
Abstract:
A slide operation control apparatus of a fail-safe press machine which has a simple circuit construction. To monitor over-run and confirm the OFF state of the power switch, which are important functions in a slide operation control of a press machine, the press machine has a fail-safe electronic circuit for signal processing in place of relay contacts.
Abstract:
A method of totalizing and displaying the total attendance of people who have passed through automatic ticket examining machines set at an entrance of a railway station or an amusement park. Each of the automatic ticket examining machines (2a, 2b, ... 2n) is adapted to read the ticket information input thereinto, and transmit the number of available remaining seats to a central system (1), which is adapted to indicate on a display for each automatic ticket examining machine a total attendance determined on the basis of the number of seats sold transmitted from each automatic ticket examining machine. This enables a clerk in charge to confirm the total attendance at the nearest automatic ticket examining machine even when the wicket or gates are provided in a plurality of places.
Abstract:
A miniature planar electromagnetic actuator. Torsion bars (6) of the actuator which support a movable plate (5) are conductive because boron is diffused in the bars (6) at a high concentration and the planar coil (7) of the actuator is electrically connected to an external power source through the torsion bars (6). Thus, no disconnection fault occurs because wiring which might break due to repetition of torsional movement of the bars (6) is eliminated, and consequently the durability and reliability of the actuator are improved.
Abstract:
A mat sensor having high reliability, the failure of which is detectable even if it is temporary. In the first invention, two sensor portions (21, 22) are disposed as shown in the figure, and the states (ON/OFF) of the outputs of both sensor portions (21, 22) are detected. A signal indicative of normal condition is generated when the output states of the sensor portions (21, 22) are coincident. Under this condition a mechanical movement is permitted to operate if both sensor portions (21, 22) are OFF. In the second invention, an object is detected from a change in the capacitance value of a sensor portion. Even though only one sensor portion is used, a mechanical movement can be stopped by detecting even a temporary contact failure resulting from degradation of the sensor portion.
Abstract:
A fail-safe apparatus for monitoring traffic signals provided at crossings and to the control unit therefor. Sensor means detects the state of individual traffic lights, generates an output indicative of normal operation and having a logic value 1 corresponding to a high energy state when the number of lights in ON or OFF state is a predetermined number, and generates an output indicative of abnormal operation and having a logic value 0 corresponding to a low energy state when the number is not the predetermined number. Accordingly, when the monitor is out of order and the output stops, the output state becomes equal to the state where signals are abnormal that is, fail-safe monitoring and control of traffic signals can be achieved.
Abstract:
A detector (1) outputs a signal e1 corresponding to the operation of an object having an operation characteristic in which a transition from a first state to a second state occurs. A first state detection circuit (2) generates a first output signal SA corresponding to the first state on the basis of the signal e1 supplied thereto from the detector (1). A second state detection circuit (3) generates a second output signal SB corresponding to the second state on the basis of the signal supplied thereto from the detector (1). The second output signal SB is generated only when a transition occurs normally from the first state to the second state and during the period in which the first output signal SA is active. A state judgement circuit (4) generates a state judgement output signal Z under the condition that both of the first and second output signals SA and SB have a period in which they are simultaneously at a high level.
Abstract:
Detection means detects the change of an impedance occurring in a coil in response to irregularities on the surface of a movable portion, and outputs its detection signal. A speed judgement circuit receives the detection signal from the detection means, and continuously generates a high level output signal when the detection signal changes after a predetermined time interval. A level detection circuit receives the detection signal, and generates a high level output signal when the detection signal is above a predetermined level. An AND circuit receives the output signals from the speed judgement circuit and the level detection circuit, and generates the output signal of the AND calculation. A movable portion stop report is made on the basis of confirmation that the delay of the report of the stop of the movable portion is reduced and moreover, a coil is normally combined with the movable portion, and the confirmation that the movable portion has been monitored immediately before the stop of the movable portion.
Abstract:
A rotation detecting means detects the rotation of a movable portion and outputs a detection signal in accordance with a rotational speed. A rotation monitoring circuit outputs a rotating signal when a detection signal sent from the rotation detecting means indicates the rotation of the movable portion. A rotation-stop monitoring circuit outputs a rotation-stop signal when a detection signal supplied from the rotation detecting means indicates a rotational speed which is lower than a predetermined rotational speed. A movable portion control circuit uses at least one of a rotating signal and a rotation-stop signal and an external command signal as input signals and controls the movable portion by logics thereof. Thus, a device is obtained which uses a rotation-stop signal and a rotating signal as signals for securing safety for an operator against the mechanical movable portion so as to secure safety.