AUTOMOTIVE MULTIPLEX SYSTEM

• US 3,651,454 A
• Filed: 12/15/1969
• Issued: 03/21/1972
• Est. Priority Date: 12/15/1969
• Status: Expired due to Term

• Current Assignee: BorgWarner Incorporated
• Original Assignee: Harry J. Venema, Kenneth W. Padgitt
• Inventors: Padgitt, Kenneth W., Venema, Harry J.
• Primary Examiner(s): Waring, Alvin H.
• Application Number:
  US04/885,384
• Time in Patent Office: 827 Days
• Field of Search: 340/52,27,179,180,181,182,183,184,185,201,203 307/10
• US Class Current: 340/459
• CPC Class Codes: G07C 5/0816 Indicating performance data, e.g. occurrence of a malfunction
• CPC Class Codes: G08C 15/12 the signals being represented by pulse characteristics in transmission link

Abstract

A multiplex system for controlling and sensing various component parts such as head lights, engine temperature, fuel level, and turn signal lights is disclosed. The system employs a single twowire cable to communicate both power and signals between such components and a central control and metering console which may be the instrument dash console. Time multiplex is employed using a reverse polarity for clock pulses from that of the information pulses. Both analog and digital data may be accommodated by using pulse-width modulation as well as bi-level modulation. Receiving units employ a N delay one-shot triggered by the clock pulse and an AND circuit driven by the output of the N delay one-shot and the signal present on the single signal wire, to drive a one-shot which controls a switching device. Similar circuitry is employed for the digital transmitting and the analog transmitter and receiver. A socket input unit for tapping into the single cable in parallel to other input units by employing a piercing plug is disclosed.

Claims

1. A vehicle multiplex system for communicating control and power to vehicle components and/or for monitoring certain conditions of vehicle components, comprising:

a two conductor cable traveling about the vehicle and having a power conductor for carrying DC power and a signal conductor;

a clock pulse source coupled to said signal conductor;

a plurality of transmitters for transmitting in definite time channels defined in relation to the pulses of said clock pulse source, coupled to said signal conductor, and each controlled to produce a signal in response to a condition of the vehicle;

a plurality of receivers also coupled to said signal conductor, at different locations thereof, each for receiving signals in one of the definite channels, and associated with a component of the vehicLe for controlling its condition.

2. The system defined in claim 1 wherein one of said plurality of receivers comprises:

a delay one-shot response to the clock pulses to produce an output signal which is time delayed therefrom by an amount of time;

a +Nt, wherein '"'"''"'"''"'"''"'"'a'"'"''"'"''"'"''"'"' is a constant and '"'"''"'"''"'"''"'"'N'"'"''"'"''"'"''"'"' is a positive whole integer and '"'"''"'"''"'"''"'"'t'"'"''"'"''"'"''"'"' is the time allocated for one channel, an AND gate coupled to said signal line and said delay one-shot to produce an output signal which is coupled to said signal line.

3. The system defined in claim 1 wherein one of said transmitters comprises:

a delay one-shot responsive to the clock pulses to produce an output which is time delayed therefrom by an amount of time;

+Nt wherein '"'"''"'"''"'"''"'"'N'"'"''"'"''"'"''"'"' is Zero or a positive whole integer and '"'"''"'"''"'"''"'"'t'"'"''"'"''"'"''"'"' is the time allocated for one channel, means for coupling said output to selectively produce or not produce a signal on said signal line.

4. The system of claim 1, wherein:

said clock pulse source and said signals are pulses of opposite polarity to one another from a normal-no signal potential level to aid in discrimination therebetween.

5. The system of claim 1, wherein:

at least one of said plurality of transmitters puts out a pulse signal whose width in its assigned time channel is varied in proportion to a sensed monitored condition of a component of the automobile.

6. A vehicle multiplex system for communicating control and power between components such as dash switches and lamps and/or for monitoring certain conditions of components and communicating information thereon to other components, such as between fuel level sensors and indicating meters, comprising:

a conductor cable (60) traveling about the vehicle and having a separate power conductor (60P) and signal conductor (60S);

a DC power source connected to the power conductor;

a clock signal source (101) coupled to said signal conductor for generating a clock signal thereon;

a plurality of transmitters (73,

     102) having delay means responsive only to said clock signal for transmitting in different definite time channels defined in relation to the clock signals determined by the delay of said delay means; and

a plurality of receivers (75,

     103) having delay means responsive only to said clock signal also coupled to said signal conductor for receiving signals from said transmitters in definite time channels determined by the delay of said receiver delay means;

said transmitters and receivers being associated with different vehicle components for respectively activation thereby and control thereof.

7. The invention as defined in claim 6 wherein:

at least one of said plurality of transmitters (130) are coupled to an analog output vehicle component (137) and produces a pulse whose width is modulated in response thereto;

at least one of said plurality of receivers (140) receives signals in the same channel in which said at least one transmitter (130) transmits and has its output coupled to an analog display device (138).