BATTERY CURRENT SENSOR

• US 20130200903A1
• Filed: 09/23/2011
• Published: 08/08/2013
• Est. Priority Date: 09/28/2010
• Status: Active Grant

• Current Assignee: LEM International SA (LEM Holding SA)
• Original Assignee: Gerard Lepine
• Inventors: Labbe, Arnaud, Lepine, Grard, Pauchet, Erick
• Granted Patent: US 9,535,130 B2
• Time in Patent Office: Days
• US Class Current: 324/437
• CPC Class Codes: G01R 15/183 using transformers with a magnetic core
• CPC Class Codes: G01R 15/20 using galvano-magnetic devices, e.g. Hall-effect devices , i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
• CPC Class Codes: G01R 31/364 Battery terminal connectors with integrated measuring arrangements
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: H01R 11/281 for connections to batteries
• CPC Class Codes: H01R 13/6683 with built-in sensor
• CPC Class Codes: H01R 2201/26 for vehicles

Abstract

Battery current sensor comprising a battery post connection clamp portion (2) comprising a tubular clamping body configured to be clamped around a terminal post (3) of a battery (5), and a current sensing portion (16) comprising a magnetic circuit (16) and a magnetic field sensor (18). The magnetic circuit comprises a magnetic core surrounding the tubular clamping body (6).

Claims

1. Battery current sensor comprising a battery post connection clamp portion comprising a split tubular clamping body configured to be clamped around a terminal post of a battery, flanges extending from free ends of the split tubular clamping body, configured to be biased together for tightening the tubular clamping body on a battery terminal post, a current sensing portion comprising a magnetic circuit, and an insulating and protective housing surrounding the magnetic circuit and at least a portion of the tubular clamping portion, wherein the flanges have a height (H2) that is less than a height (H1) of the tubular clamping body and wherein the magnetic circuit comprises a magnetic core surrounding a portion of the tubular clamping body adjacent the flanges.

2. Battery current sensor according to claim 1, wherein the flanges are positioned at a top end of the tubular clamping body and the magnetic circuit is positioned below the flanges towards a bottom end of the clamping body, said top end of the tubular clamping body having an inner diameter smaller than an inner diameter of said bottom end of the tubular clamping body.

3. Battery current sensor according to claim 1, wherein the magnetic circuit is positioned in the current sensor configured such that when the current sensor is mounted on a battery post the magnetic circuit is proximate and adjacent an upper outer surface of the battery.

4. Battery current sensor according to claim 1, further comprising a connector having a housing portion integrally formed with the current sensor housing and configured for connection to a connector of external circuitry.

5. Battery current sensor according to claim 3 or 4 further comprising a temperature sensor mounted in the housing.

6. Battery current sensor according to claim 1, wherein the current sensor has an overall height and size configured to fit within a terminal post well of an automotive battery of the lead-acid type.

7. Battery current sensor according to claim 1, wherein the magnetic circuit comprises a magnetic core having an air gap, and a magnetic field sensor positioned in the air gap.

8. Battery current sensor according to claim 7, wherein the magnetic circuit and magnetic field sensor are configured to operate as an open-loop current sensor.

9. Battery current sensor according to claim 7 or 8, wherein the magnetic field sensor comprises a circuit board on which a magnetic field detector is mounted.

10. Battery current sensor according to claim 1, wherein the current sensing portion is configure to function in a closed-loop manner and comprises a secondary coil wound around the magnetic circuit that is driven with a current that seeks to cancel the magnetic field generated by the current flowing through the battery post.

11. Battery current sensor according to claim 1 or 10 wherein the magnetic core completely surrounds, without air gap, the tubular clamping body.

12. Battery current sensor according to claim 11 wherein the current sensing portion is configured as a fluxgate sensor and comprises a coil wound around the magnetic core, the magnetic core being made of a soft saturable magnetic material.