TRAFFIC VOLUME COMPUTER

• US 3,711,686 A
• Filed: 06/08/1971
• Issued: 01/16/1973
• Est. Priority Date: 06/08/1971
• Status: Expired due to Term

• Current Assignee: Peter F. Apitz
• Original Assignee: Peter F. Apitz
• Inventors: Apitz, Peter F.
• Primary Examiner(s): Morrison, Malcolm A.
• Assistant Examiner(s): Smith, Jerry
• Application Number:
  US05/151,093
• Time in Patent Office: 588 Days
• Field of Search: 235/150.2,150.24,92TC 340/31R,31A,38R,39 343/8,112TC 307/226,220
• US Class Current: 701/118
• CPC Class Codes: G06F 7/68 using pulse rate multipliers or dividers pulse rate multipliers or dividers per seG06F7/70 takes precedence ; frequency division in electronic watches G04G3/02; frequency multiplication or division in oscillators H03B19/00; frequency dividing counters per se H03K23/00 - H03K29/00
• CPC Class Codes: G08G 1/0104 Measuring and analyzing of parameters relative to traffic conditions

Abstract

The output of a vehicle detector which provides an indication for each vehicle passing a point on a roadway is multiplied by an appropriate scaling factor. This scaled signal is then divided by factors in accordance with a predetermined sample cycle length and the number of sampling cycles used to form a complete sampling period. The signal so derived is then divided by a selected scale factor which represents a standard or reference vehicle volume per unit of time. A signal is thus derived which represents the volume of traffic per unit of time as a percentage of the selected standard or reference volume, this information being digitally accumulated during each sampling period and read out for display or use in computing circuits.

Claims

1. In a system for computing the volume of traffic at a location along a roadway, said system including detector means for generating a digital signal for each vehicle passing said location and means responsive to said detector means for generating a digital signal in accordance with the volume of vehicles passing said location during a predetermined sampling period, the improvement comprising:

selector switch means for selecting a factor representing reference volume, means for dividing the volume signal by the selected reference volume factor to produce a digital signal in accordance with the ratio therebetween, and means for providing a readout of said ratio signal.

2. The system of claim 1 wherein said means for providing a readout signal comprises a predetermined count accumulator for accumulating said digital signal in accordance with ratio, the output of said accumulator representing said ratio as a percentage.

3. The system of claim 2 and further comprising means for terminating the digital input to said accumulator when said predetermined count has been reached.

4. The system of claim 2 wherein said means for providing a readout signal further includes an output register for receiving the output of said accumulator, and gating means for gating out the signal on said register.

5. The system of claim 1 wherein said means for dividing the volume signal comprises a units and tens divider and means for decoding the outputs of said dividers to decimal form.

6. The system of claim 5 wherein said selector switch means comprises a selector switch connected to each of said decoding means for selecting desired outputs thereof.

7. The system of claim 1 wherein is included clock pulse generator means for generating a series of clock pulses for controlling the functions of said system in an ordered sequence and defining the end of each sampling period, predetermined ones of said clock pulses being respectively fed to said selecting means, said dividing means and said readout providing means.

8. A system for providing continuous successive reaDouts of the vehicle traffic volume at a location along a roadway comprising:

detector means for providing a digital signal in accordance with the number of vehicles passing said location;

means for multiplying said signal in accordance with the number of vehicles by a predetermined factor;

cycle length divider means for dividing the multiplied signal by a factor in accordance with a predetermined sample cycle length;

cycles/sample divider means for dividing the output of said cycle length divider means by a factor in accordance with the predetermined number of cycles in each sampling period;

selectable scale factor divider means for dividing the output of said cycles/sample divider means by a preselected scale factor which represents a standard of reference vehicle volume per unit of time, the output of said scale factor divider means indicating the volume of traffic per unit of time as a proportion of the selected reference volume;

accumulator means for digitally accumulating the output of said scale factor divider means; and

means for reading out the signal accumulated in said accumulator means during successive predetermined sampling periods.

9. The system of claim 8 wherein said pre-determined multiplying factor is 1440.

10. The system of claim 8 wherein said scale factor divider comprises a units counter and a tens counter, means for decoding the outputs of each of said counters to decimal form, switch means for selecting decoded outputs of said counters, and means responsive to the output of said switch means for resetting said counters when the selected count has been reached.

11. The system of claim 8 wherein said accumulator means has a predetermined count, the output thereof representing the vehicle volume as a percentage of the reference volume.

12. The system of claim 11 and further comprising means for terminating the digital input to said accumulator when said predetermined count has been reached.

13. The system of claim 8 wherein is included clock pulse generator means for generating a series of clock pulses for controlling the functions of said system in an ordered sequence and signaling the end of each sampling period, predetermined ones of said clock pulses being respectively fed to said multiplying means, said cycle length divider means, said cycles/sample divider means, said scale factor divider means and said accumulator means.