Multiplex system for monitoring engine status

• US 4,503,431 A
• Filed: 07/17/1983
• Issued: 03/05/1985
• Est. Priority Date: 09/29/1980
• Status: Expired due to Fees

• Current Assignee: Consolidated Investments and Development Corporation
• Original Assignee: Consolidated Investments and Development Corporation
• Inventors: Raab, Herman P.
• Primary Examiner(s): Groody, James J.
• Application Number:
  US06/458,447
• Time in Patent Office: 597 Days
• Field of Search: 340/870.13, 340/870.14, 340/310 A, 340/52 R, 340/52 F, 370/85, 370/92
• US Class Current: 340/870.13
• CPC Class Codes: G08C 15/12 the signals being represented by pulse characteristics in transmission link

Abstract

An engine status telemetry system includes engine parameter sensors, a transmitter, a receiver, and a display mechanism. The transmitter and receiver are time-division multiplexed such that the sensed parameter data is sent in time-serial channels from the transmitter and received and steered by the receiver in parallel format to the display mechanism. The transmitter and receiver are connected by a two-conductor link along which not only the multiplexed data is sent, but also along which the power to operate the receiver and display mechanism is sent. This minimizes the number of conductors which have to be run between the transmitter and receiver, or alternatively, between each of the transmitter and receiver and one or more power supplies. The engine status telemetry system further includes a circuit for determining whether the engine electrical system battery voltage and voltage regulator output voltage are within an acceptable voltage range regardless of whether the system is a 12 VDC or 24 VDC system. This circuit includes a resistor-based voltage-scaling circuit, a zener diode reference voltage circuit, and comparators for comparing the scaled voltages across the resistor-based circuit to the reference voltage across the zener diode circuit and for switching in response to the comparison outcome. The comparator output has a first state when the battery and regulator voltage is within acceptable limits in either the 12 VDC or 24 VDC range and a second state when the sensed voltage is outside the acceptable range. Additional comparator circuitry switches the sensitivity of the resistor-scaling network between the 12 VDC and 24 VDC ranges.

Claims

1. A prime mover status data system, comprising a plurality of prime mover status sensors, a transmitter, means for coupling the sensors to the transmitter, a receiver, means for coupling the transmitter to the receiver, a utilization mechanism, and means for coupling the receiver to the utilization mechanism, wherein the transmitter and receiver are time-division multiplex devices such that the sensed data is sent in time-serial data channels from the transmitter and received and steered by the receiver to the utilization mechanism, the transmitter including means for sustaining a non-zero direct current voltage across the transmitter-receiver coupling means between data transmissions to transmit power to the receiver and utilization mechanism and means for providing zero-going data voltages across the transmitter-receiver coupling means during data transmissions, and the means for coupling the transmitter to the receiver consists essentially of two conductors, the receiver including means for sampling the received data at the geometric mean of the data channel.

2. A prime mover status data system, comprising a plurality of prime mover status sensors, a transmitter, means for coupling the sensors to the transmitter, a receiver, means for coupling the transmitter to the receiver, a utilization mechanism, and means for coupling the receiver to the utilization mechansim, the transmitter and receiver being time-division multiplex devices such that the sensed data is sent in time-serial data channels from the transmitter and received and steered by the receiver to the utilization mechanism, the transmitter including means for sustaining a non-zero direct current voltage across the coupling means between data transmissions to transmit power to the receiver and utilization mechanism and means for providing zero-going data voltages across the transmitter-receiver coupling means during data transmissions, the receiver including means for sampling the data from the transmitter at the geometric mean of the data channel.

3. An engine status data system, comprising a plurality of engine parameter sensors, a transmitter, means for coupling the sensors to the transmitter, a receiver, means for coupling the transmitter to the receiver, a utilization mechanism, and means for coupling the receiver to the utilization mechanism, wherein the transmitter and receiver are time-division multiplex devices such that the sensed parameters are sent in time-serial data channels from the transmitter and received and steered by the receiver to the utilization mechanism, the receiver including means for interrogating the data from the the transmitter at the geometric mean of the data channel.

4. The apparatus of claim 3 wherein the transmitter includes means for sustaining a non-zero direct current voltage across the transmitter-receiver coupling means between data transmissions to transmit power to the receiver and utilization mechanism and means for providing zero-going data signal voltages across the transmitter-receiver coupling means during data transmissions.

5. The apparatus of claim 3 wherein the channels are serially scanned and the utilization mechanism updated with the serially scanned information.

6. A status data system adapted to be coupled to a plurality of status data inputs, comprising a transmitter, means for coupling the data inputs to the transmitter, a receiver, means for coupling the transmitter to the receiver, a utilization mechanism, and means for coupling the receiver to the utilization mechanism, wherein the transmitter and receiver are time-division multiplex devices such that the sensed data is sent in time-serial channels from the transmitter and received and steered by the receiver to the utilization mechanism, the transmitter including means for sustaining a non-zero direct current voltage across the transmitter-receiver coupling means between data transmissions to transmit power to the receiver and utilization mechanism and means for providing zero-going data voltages across the transmitter-receiver coupling means during data transmissions, and the means for coupling the transmitter to the receiver consists essentially of two conductors, the receiver including means for interrogating the data from the transmitter at the geometric mean of the data transmission interval.