Electricity meter for accumulator batteries

• US 3,898,548 A
• Filed: 12/05/1973
• Issued: 08/05/1975
• Est. Priority Date: 12/06/1972
• Status: Expired due to Term

• Current Assignee: Michel Perelle, Paul Schott
• Original Assignee: Michel Perelle, Paul Schott
• Inventors: Perelle, Michel, Schott, Paul
• Primary Examiner(s): Miller, J. D.
• Assistant Examiner(s): Hickey, Robert J.
• Application Number:
  US05/421,754
• Time in Patent Office: 608 Days
• Field of Search: 320/39,40,43-45,48 307/125 324/29.5,76A 235/150.51
• US Class Current: 320/134
• CPC Class Codes: G01R 21/133 by using digital technique
• CPC Class Codes: G01R 31/3832 without measurement of battery voltage
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: Y10S 320/21 State of charge of battery

Abstract

The present invention relates to an electricity meter, especially for an accumulator battery, operative in a forward direction (adding) or in the reverse direction (deducting) corresponding to the discharging and charging phases of the battery. The meter comprises an amplification circuit, an impulse generator having a frequency proportional to the intensity of the discharge or charging current passing through a shunt, and a device for counting and indicating the impulses. The meter further includes threshold devices and logic units permitting the counting of the impulses in a first direction only when the discharge current has an absolute value greater than a first predetermined threshold value, and permitting the counting of the the impulses in the opposite direction only when the charging current has an absolute value greater than a second predetermined threshold value.

Claims

1. An electricity meter for an accumulator battery having an adding direction of operation corresponding to charging current flowing into the battery and a deducting direction of operation corresponding to discharging current flowing out of the battery comprising:

a shunt, an amplification circuit connected to said shunt, an impulse generator connected to said amplification circuit for generating impulses having a frequency proportional to the current intensity on discharge or charge passing through said shunt, a device for counting and indicating the counted number of impulses, and threshold means and logic means coacting together for enabling the counting of said impulses in the adding direction only when the discharge current has an absolute value greater than a first pre-determined threshold value and enabling the counting of said impulses in the deducting direction only when the charging current has an absoLute value greater than a second pre-determined threshold value, a rectifier circuit connected between said impulse generator and amplification circuit and supplying at its output a voltage having the same polarity irrespective of the direction of the current in said shunt, an input circuit connected to the input of said amplification circuit and comprising two voltage dividers supplied with a stabilized voltage derived from said accumulator battery, a tapping on one of said voltage dividers being connected to an amplifier for producing a reference voltage under practically zero impedance, and the other of said voltage dividers having two arms in the lower arm of which is inserted said shunt.

2. An electricity meter as claimed in claim 1, in which said one voltage divider includes a resistance for regulating the zero setting of said meter, said resistance being connected to the stabilized voltage source.

3. An electricity meter for an accumulator battery having an adding direction of operation corresponding to charging current flowing into the battery and a deducting direction of operation corresponding to discharging current flowing out of the battery comprising:

a shunt, an amplification circuit connected to said shunt, an impulse generator connected to said amplification circuit for generating impulses having a frequency proportional to the current intensity on discharge or charge passing through said shunt, a device for counting and indicating the counted number of impulses, and threshold means and logic means coacting together for enabling the counting of said impulses in the adding direction only when the discharge current has an absolute value greater than a first pre-determined threshold value and enabling the counting of said impulses in the deducting direction only when the charging current has an absolute value greater than a second pre-determined threshold value, said device for counting and indicating comprises a device of the electronic type having an input receptive of impulses for the forward counting direction and an input receptive of impulses for the deduction direction, wherein said threshold means and logic means comprises two AND gates connected to two threshold devices giving said first and second threshold values, said threshold devices being coupled to each of said inputs respectively, and an AND gate serving as an inhibitor in cooperation with a decoding device for the zero condition of said counting and indicating device.