Method and arrangement for testing the operation of an actuating circuit of a DC motor

Patent metadata

Field	Value
Publication number	US-10014816-B2
Application number	US-201715452468-A
Country	US
Kind code	B2
Filing date	Mar 7, 2017
Priority date	Mar 7, 2016
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

A method for testing the operation of an actuating circuit of a DC motor is disclosed, wherein electrical voltage connections of the DC motor are connected to a voltage source via the actuating circuit. An operating switch is arranged between the actuating circuit and the voltage source for starting up the DC motor via the actuating circuit. When the operating switch is switched on, the actuating circuit is initialized. Initialization prompts the potential on a voltage connection of the DC motor to be checked, and an indicator is actuated if, during the check, a potential on the voltage connection of the DC motor is determined that is above a prescribed limit value.

First claim

What is claimed is:

1. A method for testing the operation of an actuating circuit for a DC motor; the actuating circuit including electronic switching elements; the DC motor having electrical voltage connections configured to connect to the actuating circuit; the actuating circuit being connected to a voltage source having a supply voltage U v ; the actuating circuit being configured to apply an operating voltage U B to the electrical voltage connections of the DC motor for the operation thereof; the supply voltage U v being greater than the operating voltage U B ; the electrical voltage connections further being connected to an operating switch arranged between the actuating circuit and the voltage source; and, the operating switch being configured to start the actuating circuit as well as the DC motor; the method comprising:
switching on the operating switch at a first point in time t 1 ;
initializing the electronic switching elements of the actuating circuit with said switching on of the operating switch;
detecting a potential on one of the voltage connections of the DC motor within a time window ΔT after the first point in time t 1 of the initialization of the actuating circuit and prior to an electrical start-up of the DC motor; and,
actuating an indicator when, within said time window ΔT after the first point in time t 1 , the potential detected at the voltage connection of the DC motor is greater than a predetermined limit value.

2. The method of claim 1 , wherein said detecting the potential at the voltage connection is performed within the time window ΔT of said initialization.

3. The method of claim 1 , wherein the time window ΔT lies in a range from 5 to 500 milliseconds.

4. The method of claim 1 , wherein a testing device configured to detect the potential at the voltage connection is started when the operating switch is switched on.

5. The method of claim 1 , wherein the limit value is derived from an allowable potential course at a starting of the DC motor.

6. The method of claim 1 , wherein the indicator is an optical indicator.

7. A motor arrangement comprising:
a DC motor having electrical voltage connections;
an actuating circuit including electronic switching elements;
said electrical voltage connections being configured to connect to a supply voltage U v of a voltage source via said actuating circuit;
said actuating circuit being configured to set an operating voltage U B for operating said DC motor;
said supply voltage U v being greater than said operating voltage U B ;
an operating switch arranged between said actuating circuit and the voltage source and configured to start up said actuating circuit and said DC motor;
a testing device configured to detect a potential at said voltage connections of said DC motor within a time window Δt after an initialization of said actuating circuit begins at a point in time t 1 and prior to said DC motor starting up;
a measurement line connecting said testing device to one of said voltage connections;
an indicator; and,
said testing device being configured to actuate said indicator when the potential applied to said measurement line, within the time window ΔT starting at the first point in time t 1 of the initialization of the actuating circuit and prior to a start-up of said DC motor, is above a predetermined limit value.

8. The motor arrangement of claim 7 further comprising:
a housing; and,
said testing device and said actuating circuit being arranged in said housing.

9. The motor arrangement of claim 7 further comprising:
a housing;
a circuit board disposed in said housing; and,
said testing device and said actuating circuit being arranged on said circuit board.

10. The motor arrangement of claim 7 , wherein:
the voltage source is configured to supply the supply voltage U v ; and,
the supply voltage U v is greater than a permissible operating voltage U B of said DC motor.

11. The motor arrangement of claim 7 , wherein said indicator is an optical indicator.

12. The motor arrangement of claim 7 , wherein said indicator is a light emitting diode.

13. The motor arrangement of claim 7 , wherein the voltage source is a battery pack.

14. The motor arrangement of claim 7 , wherein the voltage source is a battery pack having a plurality of lithium based individual cells.

15. An arrangement for checking the operation of an actuating circuit of a motor arrangement; the actuating circuit including electronic switching elements, the motor arrangement including a DC motor having electrical voltage connections, an actuating circuit, the electrical voltage connections being configured to connect to a supply voltage U v of a voltage source via the actuating circuit, the actuating circuit being configured to set an operating voltage U B for operating the DC motor, the supply voltage U v being greater than the operating voltage U B , an operating switch arranged between the actuating circuit and the voltage source and configured to start up the actuating circuit and the DC motor, and an indicator; the arrangement comprising:
a testing device configured to detect a potential at said voltage connections of said DC motor within a time window Δt after an initialization of said actuating circuit begins at a first point in time t 1 and prior to said DC motor starting up;
a measurement line connecting said testing device to one of the voltage connections;
said testing device being configured to actuate the indicator when, within the time window ΔT starting at the first point in time t 1 of the initialization of the control circuit and prior to said DC motor starting up, the potential applied to said measurement line is above a predetermined limit value.

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Gurr Kay-Steffen
• Liebhard Gernot

Classifications

• H02P29/024

  Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load · CPC title

• H02P29/0241 Primary

  the fault being an overvoltage · CPC title

• H02P7/285

  controlling armature supply only · CPC title

• G05B23/0259 Primary

  characterized by the response to fault detection · CPC title