ELAPSED TIME AND TERMINAL SPEED COMPUTER FOR AUTOMOTIVE VEHICLES

• US 3,748,580 A
• Filed: 11/13/1970
• Issued: 07/24/1973
• Est. Priority Date: 11/13/1970
• Status: Expired due to Term

• Current Assignee: Harmon Industries, Inc. (GE Aerospace)
• Original Assignee: Dennis D. Miller, Forrest H. Ballinger, Harry S. Stevens, Jerry W. Karr
• Inventors: Stevens, Harry S., Ballinger, Forrest H., Karr, Jerry W., Miller, Dennis D.
• Primary Examiner(s): Lynch, Michael J.
• Application Number:
  US05/089,263
• Time in Patent Office: 984 Days
• Field of Search: 324/160,162,178-180,186,166,168,171,173-175,158MG 235/92A,92T,104,105.2,151.32 58/39.5,152E,145 73/514,518,519 340/262,263
• US Class Current: 324/178
• CPC Class Codes: G01P 3/487 delivered by rotating magnets
• CPC Class Codes: G01P 3/489 Digital circuits therefor
• CPC Class Codes: G01P 3/66 using electric or magnetic means G01P3/80 takes precedence; measuring short time intervals G04F8/00, G04F10/00
• CPC Class Codes: G04F 10/04 by counting pulses or half-cycles of an ac G04F10/005 takes precedence

Abstract

A speed and elapsed time computer has a digital display in view of the driver of an automotive vehicle. A row of selector switches permits the driver to select one of several modes of operation, including '"'"''"'"''"'"''"'"'speedometer,'"'"''"'"''"'"''"'"' '"'"''"'"''"'"''"'"'terminal speed,'"'"''"'"''"'"''"'"' and '"'"''"'"''"'"''"'"'elapsed time.'"'"''"'"''"'"''"'"' A magnetic pickup senses the rotation of an undriven wheel, and wheel pulses are produced in response to the sensed rotation. In the elapsed time mode, timing signals from a time base oscillator are counted from the time the vehicle leaves a standing start until a number of wheel pulses have been produced corresponding to a predetermined distance, such as a quarter mile. At the end of the run, the elapsed time is displayed; the driver may then operate the terminal speed switch and the speed reached at the end of the quarter is displayed. Speed is computed from the period of a wheel revolution obtained from the wheel pulses, and from the number of pulses produced by the vehicle in traversing a given distance, which may also be a quarter mile. In the speedometer mode, the speed computer operates continuously and its output is continuously displayed. Calibration of the apparatus is readily accomplished by a calibration mode which is also selectable by the operator, in which mode the vehicle is driven over a measured course to determine the number of wheel pulses produced, in order that this characteristic of the particular vehicle may be preset into the computer.

Claims

1. Apparatus for computing the time required for a vehicle to travel over a course of predetermined length and the terminal speed thereof, said apparatus comprising:

a time base oscillator for producing a series of timing signals occurring at predetermined time intervals;

an elapsed time counter for receiving said signals;

means responsive to movement of said vehicle for producing a train of pulses, the number of which is indicative of the distance traveled by the vehicle and which occur at intervals dependent upon the speed of the vehicle;

control means operably associated with said counter and said movement responsive means for rendering the counter operational at the outset of said course, whereby said timing signals are received and counted by the counter, and for terminating operation of the counter when the number of said pulses thereafter occurring corresponds to the length of said course; and

speed computing means coupled with said control means for determining the terminal speed of the vehicle when said number of pulses occurs corresponding to the length of said course.

2. The apparatus as claimed in claim 1, said control means including means responsive to said pulses for counting the latter and for delivering an output command to effect said termination of counter operation when the number of pulses counted corresponds to the length of said course.

3. The apparatus as claimed in claim 2, said control means further including gating means for effecting delivery of said timing signals to said elapsed time counter at the outset of said course, said gating means terminating delivery of said signals in response to said command.

4. The apparatus as claimed in claim 1, said control means including a pulse counter, count presetting means operable prior to operation of said elapsed time counter for causing the pulse counter to store a number representing the number of said pulses corresponding to the length of said course, and means for delivering said pulses to said pulse counter to cause the latter to count from said stored number, said pulse counter delivering an output command to effect said termination of operation of the elapsed time counter after counting to a state eliminating said stored number.

5. The apparatus as claimed in claim 4, said control means further including gating means for effecting delivery of said timing signals to said elapsed time counter at the outset of said course, said gating means terminating delivery of said signals in response to said command.

6. The apparatus as claimed in claim 1, said movement responsive means including a pickup device for sensing the rotation of an undriven wheel of said vehicle, and means responsive to said device for delivering a constant number of said pulses during each revolution of said wheel.

7. The apparatus as claimed in claim 1, there being readout means for displaying time and speed information;

and switching means coupled with said counter, said speed computing means, and said readout means for selectively connecting the outputs of the counter and the speed computing means with the readout means.

8. Apparatus for computing the speed of a moving vehicle at the end of a course of predetermined length, said apparatus comprising:

first means responsive to rotation of a wheel of said vehicle for producing a train of wheel pulses which have a repetition rate Indicative of the period of a wheel revolution;

second means responsive to said wheel pulses for deriving a series of speed information signals having a time duration from the beginning to the end of said series governed by the interval between a pair of said wheel pulses, said signals having a characteristic indicative of the number of said wheel pulses that occur when the vehicle travels a predetermined distance, said second means having control means for providing a gate pulse equal in duration to said interval, and means responsive to said gate pulse for delivering said series of speed information signals;

output means coupled with said control means for indicating the speed of the vehicle upon delivery of said signals thereto;

computing means coupled with said first means and responsive to said wheel pulses for determining the instant that the vehicle finishes traveling over said course; and

means responsive to said computing means and coupled with said control means for activating the latter to provide said gate pulse as the vehicle finishes said course, whereby said output means indicates the terminal speed of the vehicle.

9. A method of computing the time consumed by a vehicle in traveling over a course of predetermined length and the terminal speed thereof, said method comprising the steps of:

producing a series of timing signals occurring at predetermined time intervals;

producing a train of pulses in response to movement of the vehicle, the number of which is indicatve of the distance traveled by the vehicle and which occur at intervals dependent upon the speed of the vehicle;

counting said timing signals beginning at the outset of said course and until the number of said pulses thereafter occurring corresponds to the length of said course; and

at the end of said course, deriving the speed of the vehicle from the interval between a pair of said pulses then occurring and said number of pulses corresponding to the length of the course, whereby to compute both the elapsed time in traveling the course and the terminal speed.

10. A method of computing the speed of a moving vehicle at the end of a course of predetermined length, said method comprising the steps of:

producing a train of wheel pulses in response to rotation of a wheel of said vehicle, said pulses having a repetition rate indicative of the period of a wheel revolution;

determining in response to said wheel pulses the instant that the vehicle finishes traveling over said course;

delivering a series of speed information signals at said instant having a time duration from the beginning to the end of said series governed by the interval between a pair of said wheel pulses then occurring, said signals having a characteristic indicative of the number of said wheel pulses that occur when the vehicle travels a predetermined distance; and

mathematically processing said series of signals to derive the terminal speed of the vehicle.

11. The method as claimed in claim 10, said processing of said series of signals including deriving therefrom a number representing the time required for the vehicle to travel said distance, and dividing the last mentioned number into a fixed number having a value depending upon the expression desired for the quotient.

12. Apparatus for computing the time required for a vehicle to travel over a course of predetermined length, said apparatus comprising:

a time base oscillator for producing a series of timing signals occurring at predetermined time intervals;

an elapsed time counter for receiving said signals;

means responsive to movement of said vehicle for producing a train of pulses, the number of which is indicative of the distance traveled by the vehicle and which occur at intervals dependent upon the speed of the vehicle;

control means operably associated with said counter and said movement responsive means for rendering the counter operational at the outset of said course, whereBy said timing signals are received and counted by the counter, and for terminating operation of the counter when the number of said pulses thereafter occurring corresponds to the length of said course, said control means including a pulse counter, count presetting means operable prior to operation of said elapsed time counter for causing the pulse counter to store a number representing the number of said pulses corresponding to the length of said course, and means for delivering said pulses to said pulse counter to cause the latter to count from said stored number, said pulse counter delivering an output command to effect said termination of operation of the elapsed time counter after counting to a state eliminating said stored number;

a calibration switch operable to effect delivery of said pulses to said pulse counter to cause the latter to count from zero as the vehicle travels said course; and

means responsive to said pulse counter for displaying the number counted during calibration operation, said count presetting means being selectively operable to set the count stored by said pulse counter prior to timing a run over said course at a value corresponding to the number displayed during calibration operation after traveling said course.