Temperature responsive battery tester

• US 5,825,174 A
• Filed: 12/19/1996
• Issued: 10/20/1998
• Est. Priority Date: 05/07/1993
• Status: Expired due to Fees

• Current Assignee: Jack Brass
• Original Assignee: Jack Brass, Robert M Parker
• Inventors: Parker, Robert
• Primary Examiner(s): Karlsen, Ernest F.
• Application Number:
  US08/769,648
• Time in Patent Office: 670 Days
• Field of Search: 324/106, 324/104, 324/96, 324/429, 324/433, 324/435, 324/438, 359/44, 429/90, 429/92, 429/93
• US Class Current: 324/106
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: G01R 19/225 by means of thermocouples or other heat sensitive elements
• CPC Class Codes: G01R 31/374 with means for correcting the measurement for temperature or ageing
• CPC Class Codes: G01R 31/386 using test-loads
• CPC Class Codes: G01R 31/388 involving voltage measurements
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 6/505 Cells combined with indicating means for external visualization of the condition, e.g. by change of colour or of light intensity
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A device for measuring the voltage of a voltage source includes a number of temperature responsive displays and a circuit including a number of heating circuits, each heating circuit for heating one of the temperature responsive displays when a threshold voltage of the heating circuit is exceeded, and a printed resistor, each heating circuit being connected to a length of the printed resistor such that the voltage of the voltage source at which each heating circuit heats a temperature responsive display is a function of the ratio of the lengths of the printed resistor to which the heating circuits are connected.

Claims

1. A device for measuring the voltage of a voltage source comprising a plurality of temperature responsive displays and a circuit including plural heating circuits, each heating circuit for heating one of said plurality of temperature responsive displays when a threshold voltage of the heating circuit is exceeded, and a printed resistor, each heating circuit being connected to a length of said printed resistor such that the voltage of the voltage source at which each heating circuit heats a temperature responsive display is a function of the ratio of the lengths of said printed resistor to which said heating circuits are connected.

2. The device of claim 1, wherein each heating circuit includes a diode.

3. The device of claim 2, wherein said diode is a zener diode.

4. The device of claim 1, wherein said zener diodes in said plural heating circuits have the same threshold conducting voltage.

5. The device of claim 3, wherein said temperature responsive displays include a thermochromic material.

6. The device of claim 1, wherein the voltage source is connected across said printed resistor in parallel.

7. The device of claim 1, wherein at least one of said plural heating circuits is connected to a length of said printed resistor in series and to a different length of said printed resistor in parallel.

8. The device of claim 6, including a shunt switch for selectively determining the length of said printed resistor to which the voltage source is connected.

9. A device for measuring the voltage of a voltage source comprising a plurality of temperature responsive displays and a circuit including plural heating circuits, each heating circuit for heating one of said plurality of temperature responsive displays when a threshold voltage of the heating circuit is exceeded, and at least one printed resistor, each heating circuit being connected to a printed resistor such that the voltage of the voltage source at which each heating circuit heats a temperature responsive display is a function of the ratio of the resistances of said printed resistors to which said heating circuits are connected.