DIGITAL MULTIGAGE FOR MOTOR VEHICLE

• US 3,866,166 A
• Filed: 04/09/1974
• Issued: 02/11/1975
• Est. Priority Date: 04/09/1974
• Status: Expired due to Term

• Current Assignee: Daniel A. Crawford, William J. Kerscher III
• Original Assignee: Daniel A. Crawford, William J. Kerscher III
• Inventors: Kerscher, William J. III, Crawford, Daniel A.
• Primary Examiner(s): Waring, Alvin H.
• Application Number:
  US05/459,390
• Time in Patent Office: 308 Days
• Field of Search: 340/52R,52F,183,412,413,414,415 307/1R
• US Class Current: 340/462
• CPC Class Codes: G07C 5/0825 using optical means

Abstract

A motor vehicle condition monitoring and warning system in which various conditions such as engine temperature, oil pressure, and fuel remaining are sequentially monitored for an out-of-limits condition while fuel remaining is continuously displayed and periodically updated. The status of the other condition may be displayed on a selective basis by closure of individual selectors or the status of each of the conditions may be displayed in sequence by selection of a cycle switch.

Claims

1. Motor vehicle condition monitoring apparatus comprising:

timer means, including a plurality of selectively connectable variable resistance sensor means, for establishing when enabled a time interval related to the status of the sensor selected, oscillator means, including a plurality of selectively connectable calibrating resistor means, for producing an output signal at a frequency dependent on the calibrating resistor means selected, each calibrating resistor means being associated with a sensor means so that a particular calibrating resistor means is selected in conjunction with a particular sensor means, counter means adapted when enabled to be clocked from said oscillator means, display means adapted when enabled to display the digital value of the count stored in said counter means, counter and display control means responsive to selection of each of said sensor means for enabling said timer means and said counter means and for disabling said display means, said control means responsive to the termination of said time interval for enabling said display means and for disabling said counter means, automatic selection means for periodically selecting one of said sensor means and the associated frequency output of said oscillator means, cycle selection means for sequentially selecting each of said sensor means and the associated frequency output of said oscillator means, individual selection means for selecting other than said one of said sensor means and the associated frequency output of said oscillator means.

2. Motor vehicle condition monitoring apparatus comprising:

timer means, including a plurality of selectively connectable sensor means for establishing when enabled a time interval related to the status of the sensor selected, said sensor means including an engine temperature sensor, an engine oil pressure sensor, and a fuel sensor, oscillator means, including a plurality of selectively connectable calibrating resistor means, for producing an outpUt signal at a frequency dependent upon the calibrating resistor means selected, each calibrating resistor means being associated with a sensor means so that a particular calibrating resistor means is selected in conjunction with a particular sensor means, counter means adapted when enabled to be clocked from said oscillator means, display means adapted when enabled to display the digital value of the count stored in said counter means, counter and display control means responsive to selection of each of said sensor means for enabling said timer means and said counter means and for disabling said display means, said control means responsive to the termination of said time interval for enabling said display means and for disabling said counter means, automatic selection means for periodically selecting said fuel sensor and the associated frequency output of said oscillator means, cycle selection means for sequentially selecting each of said sensor means and the associated frequency output of said oscillator means, individual selection means for selecting said engine temperature sensor or said engine oil pressure sensor and the associated frequency output of said oscillator means.

3. In a motor vehicle provided with a source of direct current, a plurality of variable resistance sensor means including an engine temperature sensor, an engine oil pressure sensor and a fuel sensor, a digital multigage comprising a capacitor, means normally connecting said capacitor to said source to maintain said capacitor in a charged state, operator actuable manual selector means for selecting display of engine temperature or engine oil pressure, automatic selector means for periodically selecting display of fuel remaining, oscillator means for producing a pulsating output at one of three predetermined frequencies in response to selection to display engine temperature, engine oil pressure or fuel remaining respectively, logic means responsive to a manual or automatic selection for discharging said capacitor through the sensor corresponding to the display selected to establish a time interval related to the value of the resistance of the sensor, counter means for accumulating the pulses produced by said oscillator during said time interval and display means for displaying the digital value corresponding to the output of said counter means at the end of said time interval and until a manual or automatic selection is subsequently made.

4. Motor vehicle condition warning apparatus comprising:

timer means including a plurality of selectively connectable variable resistance sensor means, for establishing when enabled, a time interval related to the status of the sensors selected, oscillator means including a plurality of selectively connectable calibrating resistor means for producing an output signal at a frequency dependent of the calibrating resistor means selected, each calibrating resistor means being associated with a sensor means so that a particular calibrating resistor means is selected in conjunction with a particular sensor means, counter means adapted when enabled to be clocked from said oscillator means, indicator means, counter control means responsive to selection of each of said sensor means for enabling said counter means, said control means responsive to termination of said time interval for disabling said counter means, selector means for periodically selecting each of said sensor means and the associated frequency output of said oscillator means, means for comparing the counts accumulated in said counter means with a predetermined upper or lower limit and for energizing said indicator means when the count accumulated by said counter means is above said upper limit or below said lower limit, latch means responsive to the output of said comparator means for energizing said indicator means.

5. In a motor vehicle provided with a plurality of variable resistance sensor means including an engine temperaTure sensor, an engine oil pressure sensor, and a fuel sensor, a condition monitoring system comprising:

timer means including said sensors for establishing a time interval related to the status of the sensor selected, oscillator means including a plurality of selectively connectable calibrating resistor means for producing first, second, and third output signals at predetermined frequencies dependent on the sensor selected, first counter means adapted when enabled to be clocked from said oscillator means, display means adapted when enabled to display the digital value of the count stored in said first counter means, selection means for sequentially selecting each of said sensor means, first control means responsive to selection of said fuel sensor means for enabling said timer means and said counter means and for displaying said display means, said first control means responsive to the termination of said time interval for enabling said display means and for disabling said counter means, out-of-limits counter means responsive to the output of said counter means, second control means responsive to the selection of said engine temperature sensor or said oil pressure sensor for enabling said out-of-limits counter means, warning means, latch means for controlling the energization of said warning means, third control means responsive to said out-of-limits counter means reaching an upper limit during selection of said engine temperature sensor of the failure of said counter means to reach a predetermined lower limit during selection of said engine oil pressure for setting said latch means.