BATTERY ADAPTER

• US 3,783,378 A
• Filed: 07/31/1972
• Issued: 01/01/1974
• Est. Priority Date: 07/31/1972
• Status: Expired due to Term

• Current Assignee: Walfrid Mildner
• Original Assignee: Walfrid Mildner
• Inventors: Mildner, Walfrid
• Primary Examiner(s): Smith, Alfred E.
• Application Number:
  US05/276,690
• Time in Patent Office: 519 Days
• Field of Search: 324/73,51,15
• US Class Current: 324/430
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00

Abstract

An adapter may be quickly and easily connected between a vehicle battery and the vehicle battery terminals. A digital computer may then be connected to the adapter and may monitor the vehicle electrical system. Means are provided whereby the computer may automatically insert any one of a series of measuring resistors in series with the battery current flow so as to allow a wide variety of measurements to be made with a single adapter. Means are also provided whereby the computer may shunt the measuring resistors when excessive current levels are encountered so as to protect them from destruction.

Claims

1. A battery adapter for use in testing out a vehicle electrical system in conjunction with a computer, said adapter comprising:

a pair of clamps one of which is suitable for connection to the terminal of a vehicle battery and the other of which is suitable for connection to a vehicle battery cable;

a plurality of different-valued measuring resistors each having first and second terminals and each having an ohmic value that is selected to be suitable for use in measuring the battery current that flows to a given set of one or more electrical appliances in a motor vehicle;

connecting means attached to said measuring resistors and to said clamps for electrically connecting said clamps to the terminals of any desired one of said resistors under the control of signals generated by said computer;

an analog-to-digital converter having a pair of analog input terminals and having a digital signal output for generating a digital signal at its output representing the magnitude of an analog potential developed across its input terminals; and

means for electrically connecting the analog input terminals of said converter to the respective terminals of any measuring resistor that is electrically connected to said clamps by said connecting means.

2. A battery adapter in accordance with claim 1 wherein said connecting means comprise a plurality of relays, one corresponding to each of said measuring resistors, each having contacts arranged to electrically connect the terminals of the corresponding measuring resistors to said clamps when energized, and each having an energizing winding which can be selectively energized by the computer.

3. A battery adapter in accordance with claim 1 wherein the means for electrically connecting comprise a first circuit path connecting one of said analog input terminals to one of said clamps and a second circuit path connecting the other of said analog input terminals to the other of said clamps.

4. A battery adapter in accordance with claim 3 wherein one of said circuit paths includes resistance and which further includes a capacitor connected in parallel with said analog input terminals.

5. A battery adapter in accordance with claim 3 wherein at least one of said first and second circuit paths includes a diode which prevents reverse potentials from reaching said analog-to-digital converter.

6. A battery adapter in accordance with claim 3 which includes a relay, and wherein the contacts of said relay connect said analog input terminals to said first and second circuit paths, and wherein the contacts of said relay reverse the connection of said input terminals to said circuit paths when said relay is actuated, and wherein said relay includes an energizing winding which can be selectively energized by the computer.

7. A battery adapter in accordance with claim 1 which includes means controlled by said computer for electrically short-circuiting together said pair of clamps wherever necessary to protect said measuring resistors from excessively high currents.

8. A battery adapter in accordance with claim 1 wherein fuses are connected in series with at least some of said measuring resistors to protect the resistors from excessively high currents.

9. A battery adapter in accordance with claim 1 wherein signalling means are connected in parallel with the measurIng resistors for signalling when one of said resistors is open-circuited.

10. A battery adapter in accordance with claim 1 to which is added means connecting to a vehicle ignition coil primary circuit for bypassing the ignition coil under the selective control of said computer to facilitate the measurement of small battery currents.