REMOTE METER READ-OUT APPARATUS

• US 3,806,904 A
• Filed: 01/21/1972
• Issued: 04/23/1974
• Est. Priority Date: 01/21/1972
• Status: Expired due to Term

• Current Assignee: M&FC Holding, LLC
• Original Assignee: Bernard Last, Eugene M. Weinberger, Thomas M. Kirby
• Inventors: Weinberger, Eugene M., Last, Bernard, Kirby, Thomas M.
• Primary Examiner(s): Habecker, Thomas B.
• Application Number:
  US05/219,748
• Time in Patent Office: 823 Days
• Field of Search: 340/188R,186,203
• US Class Current: 340/870.02
• CPC Class Codes: G01F 15/063 using electrical means
• CPC Class Codes: G06M 1/276 using mechanically-actuated contacts

Abstract

A remote meter reading apparatus for reading the decimal digit positions in a multi-digit number that is registered by a meter register. According to the disclosed embodiment, the meter reading apparatus includes a circuit at the meter for encoding the registration of the register counter wheels or other meter driven elements, and a portable read-out unit that is adapted to be connected to the encoding circuit by a transmission line for indicating the meter register reading. Various features include, among other things, a circuit arrangement that requires only a three-conductor transmission line for transmitting coded signals for reading up to four different orders of digits in the meter registration, an unbalanced bridge technique for detecting the position of each meter register counter wheel, an arrangement whereby the portable read-out unit has a meter reading register and a recorder for recording the registration on the remote meter reading register, a remote meter reading circuit that is responsive to a selectively developed command signal for first resetting the remote meter reading register, then advancing the remote meter reading register to read-out the meter reading, and then activating the recorder to record the registration of the remote meter reading register, a selector for selectively setting a desired number into the remote meter reading register and a circuit arrangement for recording the desired number, a circuit arrangement for detecting and signalling electrical defects in the encoding circuit at the meter register, and a circuit arrangement providing a source of identification for recordation by the recorder in the remote meter reading unit.

Claims

1. In combination with a meter having at least one element that is displaced to different positions to indicate different metered quantities, a remote meter reading apparatus comprising a resIstance bridge circuit having a pair of output terminals, means for energizing said bridge circuit with a d.c. potential, means unbalancing said bridge circuit at its output terminals, means sensing the position of said element by effecting a reversal of the polarity of the potential measured across said output terminals, indicating means, and means under the control of the polarity of the potential at said output terminals for causing said indicating means to indicate the quantity that is indicated by the position of said element.

2. The combination defined in claim 1 wherein said indicating means comprises counter means, and wherein said means under the control of said polarity at said output terminals comprises a circuit for advancing said counter means as long as the potential across said output terminals is of one polarity, said circuit for advancing said counter means being responsive to said reversal of polarity for terminating advancement of said counter means.

3. In combination with a meter having at least one rotatable element whose rotation to different positions is indicative of different metered quantities, a remote meter reading apparatus comprising a resistance bridge circuit having a pair of output terminals and first and second legs connected to said output terminals, means for energizing said bridge circuit with a d.c. potential, means under the control of said element for providing said first leg with a different position-indicating resistance value for each of said positions of said element, means for incrementally varying the resistance in said second leg in a pre-selected direction to sequentially provide said second leg with different pre-selected values of resistance which each differ from each position-indicating resistance value for said first leg to prevent said bridge circuit from being balanced by the resistances in said first and second legs, there being a different one of said second leg resistance values for each position indicating resistance value that causes a reversal of polarity at said output terminals, means connected to said output terminals for detecting said reversal of polarity, and means under the control of said detecting means for providing an indication of the quantity that is indicated by the position of said element.

4. In combination with a meter having at least one rotatable element whose rotation to different positions is indicative of different metered quantities, a remote meter reading apparatus comprising a bridge circuit having a pair of output terminals and first and second legs connected to said output terminals, means for energizing said bridge circuit with a d.c. potential, means under the control of said element for providing said first leg with a different position-indicating resistance value for each of said positions of said element, means for sequentially providing said second leg with a series of different resistance values, said second leg resistance values being pre-selected to unbalance said bridge circuit at its output terminals for any position-indicating resistance value in said first leg, there being a different one of said second leg resistance values for each position-indicating resistance value that effects a reversal of the polarity of the potential measured across said output terminals from one polarity to the opposite polarity, means connected to said output terminals for developing a signal that is indicative of the polarity of the potential across said output terminals, and means under the control of said signal for providing an indication of the quantity that is indicated by the position of said element.

5. The combination defined in claim 4 wherein said indication-providing means comprises a recorder for recording the quantity that is indicated by the position of said element.

6. The combination defined in claim 4 wherein said bridge circuit is a four-legged bridge, and wherein said first and second legs are connected in series between said output terminals. 7. In combination with a meter having at least one rotatable element whose rotation to different positions is indicative of different metered quantities, a remote meter reading apparatus comprising a bridge circuit having a pair of output terminals and first and second legs connected to said output terminals, means for energizing said bridge circuit with a d.c. potential, means under the control of said element for providing said first leg with a different position-indicating resistance value for each of said positions of said element, pulse generator means for developing electrical pulses, means operated by said pulses for sequentially providing said second leg with a series of different resistance values to incrementally vary the resistance in said second leg in a preselected direction, said second leg resistance values being pre-selected to unbalance said bridge circuit at its output terminals for any position-indicating resistance value in said first leg, there being a different one of said second leg resistance values for each position-indicating resistance value that reverses the polarity of the potential measured across said output terminals, means connected to said output terminals for detecting the polarity of the potential across said output terminals, pulse counting means for counting pulses transmitted thereto, means under the control of said detecting means for transmitting a train of said pulses to said pulse counting means in which the number of pulses in said train is a function of the quantity indicated by the position of said element, and means under the control of said pulse counting means for providing an indication of the quantity that is indicated by the position of said element, said detecting means being effective to cause said pulse transmitting means to transmit pulses to said pulse counting means as long as the potential across said output terminals is of one pre-selected polarity, and said detecting means being responsive to the reversal of polarity of the potential across said output terminals to cause said transmitting means to terminate the transmittal of pulses to said counting means.

8. In combination with a meter having at least one rotatable element whose rotation to different positions is indicative of different metered quantities, a remote meter reading apparatus comprising a resistance bridge having a pair of output terminals, means for energizing said bridge with a d.c. potential, means for unbalancing said bridge, one side relative to the other, by a pre-selected magnitude that is peculiar to the quantity-indicating position of said element, means for changing the unbalance of said bridge in a pre-selected direction by a series of successive, descrete, pre-selected incremental steps, the magnitudes of two successive predetermined ones of said steps in said series being respectively greater than and smaller than said pre-selected magnitude to effect a reversal in the polarity of the potential at said output terminals upon changing the unbalance by the succeeding one of said two predetermined ones of said steps, means connected to said output terminals for detecting said reversal in the polarity of the potential at said output terminals, means under the control of said detecting means for supplying a train of pulses in which the number of pulses is indicative of the number of said incremental steps required to effect the reversal in polarity at said output terminals, and counter means for counting the number of pulses in said train.