Nickel-cadmium battery monitor

• US 3,940,679 A
• Filed: 06/18/1974
• Issued: 02/24/1976
• Est. Priority Date: 06/18/1974
• Status: Expired due to Term

• Current Assignee: Textron Inc
• Original Assignee: Textron Inc
• Inventors: Brandwein, Rowland, Gupta, Mohan L.
• Primary Examiner(s): Miller, J. D.
• Assistant Examiner(s): Hickey, Robert J.
• Application Number:
  US05/480,479
• Time in Patent Office: 616 Days
• Field of Search: 320/48, 320/2, 320/35, 320/36, 324/29.5, 340/248 B, 340/249
• US Class Current: 320/134
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: G01R 31/378 specially adapted for the type of battery or accumulator
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: Y10S 320/21 State of charge of battery
• CPC Class Codes: Y10S 320/33 Aircraft or spacecraft application

Abstract

The nickel-cadmium battery monitor is provided with sensors for measuring the battery temperature, the battery voltage and the magnitude of the current being charged to the battery, each of the sensors generating a sensor signal voltage that varies directly with the magnitude of the parameter being measured. The sensor signal voltages from the temperature sensor and the voltage sensor are conditioned and then converted to an analog signal voltage increment the magnitude of which corresponds approximately to the actual magnitude of the battery temperature and battery voltage as measured. The analog signal voltage increments thus obtained cause an analog visual display means to indicate visually the approximate magnitude of the battery temperature and battery voltage as measured. The conditioned analog signal voltages from the temperature sensor and the voltage sensor are also converted to a multibit digital signal which causes a digital visual display means to display in numeric form the actual magnitude of the battery temperature or battery voltage as measured. Charge rate sampling means continuously measures the magnitude of successive samples of the charge current and transmits an alarm signal to a flash alarm means when the rate of increase in the charge current exceeds a predetermined value. The flash alarm means transmits flash alarm signal to the digital visual display means when the temperature of the battery exceeds a predetermined value or when the voltage of the battery falls below or exceeds a predetermined value or when the charge rate sampling means transmits an alarm signal to the flash alarm means.

Claims

1. Device for monitoring nickel-cadmium battery which comprises:

a sensor for measuring the temperature of the battery, a sensor for measuring the voltage at the terminals of the battery and a sensor for measuring the magnitude of the current being discharged by and being charged to the battery, each of said sensors generating a sensor signal voltage that varies directly with the magnitude of the parameter being measured;

a temperature sensor signal voltage conditioning and calibrating means electrically connected to the temperature sensor, and a voltage sensor signal voltage conditioning and calibrating means electrically connected to the voltage sensor, each of said conditioning and calibrating means transforming the sensor signal voltage from the sensor connected thereto to a conditioned analog signal voltage the magnitude of which is in the same relative proportion to a predetermined reference voltage as the actual magnitude of the battery temperature is to a predetermined reference battery temperature and as the actual magnitude of the battery voltage is to a predetermined reference battery voltage;

continuous voltage gradient to incremental voltage gradient converter means electrically connected to each of said signal voltage conditioning and calibrating means, said converter means dividing the continuous voltage gradient of the conditioned analog signal voltage into a predetermined number of incrementally increasing analog signal voltage increments, whereby the actual signal voltage from each said signal voltage conditioning and calibrating means is converted to an analog signal voltage increment the magnitude of which corresponds approximately to the actual magnitude of the battery temperature and battery voltage as measured;

analog signal voltage increment indicator means electrically connected to each of the continuous to incremental voltage gradient converter means, each of said indicator means having a plurality of electrically energized visual display means, each of said display means corresponding to and being energized by one of said analog signal voltage increments, whereby said indicator means visually indicates the approximate magnitude of the battery temperature and battery voltage as measured;

selector switch means also electrically connected to each of the signal voltage conditioning and calibrating means, said selector switch being adapted to select and transmit the conditioned analog signal from the temperature signal or the voltage signal conditioning and calibrating means to an analog to digital converter means;

analog to digital converter means electrically connected to said selector switch means, said converter means converting the selected conditioned analog signal to a corresponding multibit digital signal;

an array of numeric visual display units electrically connected to said analog to digital converter means, said display units displaying in numeric form the actual magnitude of the battery temperature or the battery voltage, as selected by said selector switch means;

charge rate sampling means electrically connected to the battery charge sensor, said sampling means continuously measuring the magnitude of successive samples of the charge current and transmitting an alarm signal to a flash alarm means when the rate of increase of the charge current exceeds a predetermined values; and

flash alarm means electrically connected to each of said continuous to incremental voltage gradient converter means and to said charge rate sampling means, said alarm means transmitting a flash alarm signal to the analog to digital converter means when the temperature of the battery exceeds a predetermined value or when the voltage of the battery falls below or exceeds a predetermined value or when an alarm signal is received from the charge rate sampling means.

2. The device according to claim 1 in which the charge rate sampling means continuously measures successive samples of the charge current and records in a memory element each time the magnitude of the charge current of a given current sample exceeds by a predetermined amount the magnitude of the charge current of the immediately preceeding current sample, said sampling means transmitting an alarm signal to a flash alarm means when the number of current samples recorded in the memory element of the sampling means during a predetermined period of time exceeds a predetermined number.

3. Device for monitoring a nickel-cadmium battery which comprises:

a sensor for measuring the temperature of the battery, a sensor for measuring the voltage at the terminals of the battery and a sensor for measuring the magnitude of the current being discharged by and being charged to the battery, each of said sensors generating a sensor analog signal voltage that varies directly with the magnitude of the parameter being measured;

analog signal voltage indicator means for said temperature analog signal and for said voltage analog signal, each of said indicator means having a plurality of electrically energized visual display means, each of said display means corresponding to an analog signal voltage increment, whereby said indicator means visually indicates the approximate magnitude of the battery temperature and battery voltage is measured;

selector switch means adapted to select and transmit either the temperature analog signal or the voltage analog signal to a digital display means;

digital display means comprising an array of visual display units displaying in numeric form the actual magnitude of the battery temperature or the battery voltage, as selected by said selector switch means;

charge rate sampling means electrically connected to the battery charge sensor, said sampling means continuously measuring the magnitude of successive samples of the charge current and transmitting an alarm signal to a flash alarm means when the rate of increase of the charge current exceeds a predetermined values; and

flash alarm means transmitting a flash alarm signal to the digital display means when the temperature of the battery exceeds a predetermined value or when the voltage of the battery falls below or exceeds a predetermined value or when an alarm signal is received from the charge rate sampling means.

4. The device according to claim 3 in which:

a temperature sensor signal voltage conditioning and calibrating means is electrically connected to the temperature sensor and a voltage sensor signal voltage conditioning and calibrating means is electrically connected to the voltage sensor, each of said conditioning and calibrating means transforming the sensor signal voltage from the sensor connected thereto to a conditioned analog signal voltage the magnitude of which is in the same relative proportion to a predetermined reference voltage as the actual magnitude of the battery temperature is to a predetermined reference battery temperature and as the actual magnitude of the battery voltage is to a predetermined reference battery voltage;

a continuous voltage gradient to incremental voltage gradient converter means is electrically connected to each of said signal voltage conditioning and calibrating means, said converter means dividing the continuous voltage gradient of the conditioned analog signal voltage into a predetermined number of incrementally increasing analog signal voltage increments, whereby the actual signal voltage from each said signal voltage conditioning and calibrating means is converted to an analog signal voltage increment the magnitude of which corresponds approximately to the actual magnitude of the battery temperature and battery voltage as measured; and

an analog signal voltage increment indicator means is electrically connected to each of the continuous to incremental voltage gradient converter means, each of said indicator means having a plurality of electrically energized visual display means, each of said display means corresponding to and being energized by one of said analog signal voltage increments, whereby said indicator means visually indicates the approximate magnitude of the battery temperature and battery voltage as measured.

5. The device according to claim 3 in which

the selector switch means selects and transmits either the temperature analog signal or the voltage analog signal to an analog to digital converter means;

analog to digital converter means are electrically connected to said selector switch means, said converter means converting the selected conditioned analog signal to a corresponding multibit digital signal; and

an array of digital visual display units are electrically connected to said analog to digital converter means, said display units displaying in numeric form the actual magnitude of the battery temperature or the battery voltage, as selected by said selector switch means.

6. The device according to claim 3 in which

the charge rate sampling means continuously measures successive samples of the charge current and records in a memory element each time the magnitude of the charge current of a given current sample exceeds by a predetermined amount the magnitude of the charge current of the immediately preceding current sample, said sampling means transmitting an alarm signal to a flash alarm means when the number of current samples recorded in the memory element of the sampling means during a predetermined period of time exceeds a predetermined number.