摘要:
A dual computer system of the type comprising two simultaneously operating central processors is disclosed. The two central processors are connected to each other for processing a breakdown cycle by way of an memory bus exchanger (MBEX) for switching connections between two memory buses, a data bus exchanger (DBEX) for switching connections between the input/output signal lines of the two central processors (CP) and the data bus line, and a dual control unit (DCU) for monitoring the two central processors and controlling the MBEX and the DBEX and thus integrally controlling the dual system. The dual computer system operates through a breakdown cycle utilizing the following four modes: 1. Dual Mode: In this mode the two CP''s are fully sychronized and the output signals of the two CP''s or the outputs of registers or the like are monitored through a check circuit located in the DCU. One of the CP''s is responsible for input/output operations and the other CP remains a standby. 2. Abnormal Mode: This mode results when a discoincidence is detected in the outputs being monitored by the DCU. The input/output operations of the CP''s are halted by the DBEX until the failed CP is identified and isolated from the system. 3. Single Mode: In this mode only the normal CP is in operation. The normal CP reads the memory of the failed one through the MBEX for use in diagnosing the failure, and the failed CP is repaired. 4. Preparation Mode: In this mode the memory and register contents of the repaired CP are equalized through the MBEX with those of the normally functioning CP, and the two CP''s are synchronized to allow the system to be returned to the dual mode. In the event of failure of one of the CP''s, the normal CP assumes the single mode of operation immediately after a short halt of system operation in the abnormal mode. The failed CP is repaired, the memory and register contents of the failed CP are equalized with those of the other CP remaining on-line, and thus the dual mode is restored without substantially disturbing the flow of system operation. This enhances system reliability.
摘要:
Flow metering apparatus of the type wherein a vortex generating element having a generally elongate cylindrical shape is placed transversely in the stream of flowing fluid to produce on opposite sides of the element vortices which are shed in alternating fashion, and of the type wherein the element is formed with openings at said opposite sides which are connected together through the interior of said element to produce therethrough an alternating fluid flow corresponding to the alternating shedding of vortices. To improve the correspondence of vortex production rate with flow velocity over conditions of turbulent flow, the element has the openings on opposite sides thereof arranged both in an upstream region, and in a downstream region circumferentially spaced from the upstream region. Fluid flowing into the openings on one side of the element serves to maintain the boundary layer attached to the element to the vicinity of the downstream region to aid vortex formation. Fluid flowing outwardly from the openings on the opposite side of the element assists in separating the boundary layer and in preventing it from reattaching to the element in the vicinity of the downstream region.
摘要:
A barrier isolator device is disclosed for interconnecting a voltage source in a safe area, a load (such as a sensing element) in a hazardous area, and a load-associated device (such as a recorder) in a safe area. The barrier isolator device includes an overload protection circuit arranged to transmit signals between the load and the load-associated device, a first isolating circuit connecting the voltage source with the overload protection circuit, and a second isolating circuit connecting the load-associated device with the overload protection circuit. The protective circuit is characterized by low voltage losses in normal operation, low power consumption in a fault condition, and automatic resetting. The protective circuit comprises a current control means, such as a transistor, in series with the load and controlling the current flowing through the load by varying its conductivity. A current detection means, such as a low valued resistor, is connected in series with the load to detect the predetermined limiting value of current, and a voltage detection means, such as a resistive voltage divider, is connected parallel to the voltage source for detecting the predetermined limiting value of voltage. The current control means is arranged to be responsive to the current and voltage detection means to react to either a current or voltage overload condition by reducing its conductivity to limit current flow through, and voltage across, the load. Under normal conditions the current control means inserts a conducting transistor''s collector-emitter circuit in series with the load, and the current detecting means inserts a low valued resistor in series with the load, and hence the overload protection circuit introduces only a small series voltage loss. The voltage detecting means places large valued resistors in parallel with the voltage source, and any bias voltages provided to the current control means by the voltage source can be supplied through similar large valued resistors, and hence there is little power consumption during a voltage overload condition. The current control means and the voltage and current detection means are arranged to automatically restore themselves when overload conditions vanish. Accordingly, the overload protection circuit is highly suitable for use in intrinsically safe circuitry arranged to prevent excess energy from entering a hazardous environment, such as an explosive environment.
摘要:
A depressor bar type chart recording apparatus of the type having a dotting apparatus axially slidable on a rotating drive shaft and being activated by the rotating drive shaft to sequentially impress different colored ink dots upon the chart at selected axial locations. The dotting apparatus has a slide tube rotating with the drive shaft and carrying a dotting cam and a sequencing cam. The frame for the dotting apparatus includes a sliding portion coupled to the slide tube for axial motion therewith, and a swinging portion pivoted to the sliding portion and having a cam follower engaging the dotting cam for causing the swinging portion to be pivoted. A dotting shaft is carried by the swinging portion of the frame, and has at one end a dotting wheel with circumferentially spaced dotting needles brought into contact with the chart as the frame swings, and at the other end sequencing means engaging the sequencing cam and intermittently rotating the dotting needles into position for contacting the chart. A plate is pivotally mounted on the swinging frame portion, and carries an inkpad shell which is rotated along with the dotting shaft and is brought into contact with the dotting wheels as the plate moves inertially upon movement of the swinging frame portion.
摘要:
A servo - mechanism utilizing a pulse motor comprises a comparator amplifier for producing an output corresponding to the difference between an input signal voltage and a feedback voltage, a signal conversion circuit for converting the output from the comparator amplifier into two bit level signals, and a pulse motor driving circuit for controlling the direction of the pulse motor in accordance with one of the two bit level signals and for controlling the start and stop of the pulse motor in accordance with the other of the two bit level signals.
摘要:
A pulse transmitting apparatus comprising a first transmission line connected to a current drive circuit at one end, a second transmission line stranded with the first and having an end connected to a receiver circuit located adjacent the drive circuit, and a pair of serial connected switches at the transmitting end of the apparatus for connecting together the other ends of the first and second transmission lines and sending a current pulse signal to the receiver circuit. The switches are operated simultaneously in response to an input signal and the apparatus contains means for absorbing pulses reflected back from the receiving end to the transmitting end of the apparatus.
摘要:
A GLASS ELECTRODE HAVING SUPPORT TUBE MEANS, AN INNER ELECTRODE DISPOSED THEREIN, A CAP FORMED OF AN INSULATING MATERIAL AND FIXED ON THE TOP OF THE SUPPORT TUBE MEANS, A GLASS ELECTRODE TERMINAL PROVIDED ON THE CAP AND CONNECTED WITH THE INNER ELECTRODE, A GUARD RING FIXED ON THE PERIPHERY OF THE CAP AND A GUARD RING TERMINAL, IN WHICH A NEGATIVE FEEDBACK VOLTAGE FROM A NEGATIVE FEEDBACK AMPLIFIER IS IMPRESSED TO THE GUARD TERMINAL, THE NEGATIVE FEEDBACK AMPLIFIER AMPLIFYING A SIGNAL DERIVED AT THE GLASS ELECTRODE TERMINAL.
摘要:
A periodic averaging circuit having an integrator supplied with an input signal, a sampling hold circuit supplied with the output of the integrator and a sampling pulse, and a feedback circuit for feeding the output of the sampling hold circuit back to the integrator, the sampling hold circuit holding the output of the integrator in accordance with the sampling pulse applied thereto.
摘要:
Method and apparatus for generating signals corresponding to the moisture content of paper by irradiating a sheet of paper with a near infrared ray, by detecting a beam having a coaction with the paper and by accomplishing the desired arithmetic operations with the use of the detected signals. According to the method and apparatus, at least two optical systems having different degrees of coactions with the paper are provided to respectively detect photometric optical signals and reference optical signals so that the signals corresponding to the moisture content may be generated with the use of the photometric and reference optical signals.