Remote meter reading arrangement

• US 4,361,838 A
• Filed: 07/25/1979
• Issued: 11/30/1982
• Est. Priority Date: 07/29/1978
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Mizuta, Toshiaki
• Primary Examiner(s): Groody, James J.
• Application Number:
  US06/060,461
• Time in Patent Office: 1,224 Days
• Field of Search: 340/870.02, 340/870.03, 340/870.14, 340/870.39, 340/870.19, 340/150, 340/151, 340/310 A, 340/870.01, 179/2 AM
• US Class Current: 340/870.02
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A remote meter reading arrangement in which power for the remote terminal is supplied from the data collection terminal by transmission lines. At the moment power is applied to the remote terminal, a clock pulse generator in the remote terminal is supplied with power and begins to generate clock pulses to a counter, which successively couples each stage of the meter to the data collection terminal so that pulses of greater or lesser amplitude are generated in sequence, corresponding to each significant digit of the remote meter, to indicate the meter reading.

Claims

1. A remote meter reading arrangement, comprising:

(a) a plurality of remote terminals each comprising;

a clock pulse generator for providing a periodic train of clock pulses;

a bit counter for sequentially and repetitively enabling a series of output lines in response to successive ones of said clock pulses;

a digit counter for sequentially enabling a group of output lines, said digit counter being incremented by one each time said bit counter completes a cycle enabling said series of output lines thereof;

a remote meter having a plurality of digit value contacts coupled to respective output lines of said bit counter, and a number of digit position contacts coupled to corresponding output lines of said digit counter, each digit position contact being connected by said meter to a digit value contact indicative of the value of the digit to be read at the corresponding digit position,

whereby upon application of power to said remote terminal, each of said corresponding output lines of said digit counter is enabled for a time interval corresponding to the duration of said bit counter cycle, current flowing through said meter at a time from the beginning of each said time interval which is indicative of the value of the digit to be read at the corresponding digit position;

(b) a data collection terminal comprising;

driver circuit means for selectively supplying power to each of said remote terminals at a given time;

data signal generating means for providing a signal corresponding to the current flowing through said meter; and

a sampling pulse generator coupled to said data signal generating means for providing sampling pulses having the same period as and in synchronism with said remote terminal clock pulses;

a data collection circuit coupled to said sampling pulse generator and said data signal generating means for providing an output signal indicative of the reading of said meter; and

(c) transmission line means for connecting each of said remote terminals to said data collection terminal for providing power to said remote terminals and for coupling variations in current flow through said meter to said data signal generating means.

2. A remote meter reading arrangement as set forth in claim 1, wherein said transmission line means comprises a power supply line, a signal line and a common line.

3. A remote meter reading arrangement as set forth in claim 2, wherein power to said remote terminals and current variations indicative of said meter reading are coupled between said remote terminal and said data collection terminal by the same lines.

4. A remote meter reading arrangement as set forth in claim 1, wherein said sampling pulse generator comprises an oscillator capable of providing pulses at a frequency higher than that of said clock pulse generator in said remote terminal, during the time interval during which said clock pulse generator generates a predetermined number of clock pulses, frequency dividing means for dividing the number of pulses delivered by said oscillator by a number corresponding to said predetermined number of clock pulses, means for counting and storing a number corresponding to the output of said frequency dividing means, and preset counter means coupled to said counting and storing means and responsive to said oscillator pulses and a gating signal via a gating means for generating an output pulse every time the number of pulses delivered to said preset counter by said oscillator via said gating means reaches the counted and stored number.

5. A remote meter reading arrangement, comprising:

(a) a plurality of remote terminals each comprising;

a clock pulse generator for providing a train of pulses;

a meter having contacts interconnected in a manner indicative of the reading thereof;

a bit counter which is scanned by said clock pulses delivered from said clock pulse generator;

a digit counter which is incremented by one whenever said bit counter has counted a specified number of clock pulses;

current modulating means responsive to said clock pulses and to the logical product of an output bit of said bit counter, a position of a contact in each digit position of said meter and a bit position of said digit counter, for varying the current drawn by said remote terminal when power is supplied thereto;

(b) a data collection terminal for supplying power to said remote terminals and processing the variations in current drawn thereby to provide an output signal indicative of each corresponding meter reading, by determining the time current flows through said meter contacts after each corresponding time said digit counter is incremented, said data collection terminal including oscillator means for providing a periodic signal synchronous with said clock pulses; and

(c) transmission line means for connecting each of said remote terminals to said data collection terminal.