Control system for a floor maintenance appliance

• US 20020175648A1
• Filed: 05/21/2002
• Published: 11/28/2002
• Est. Priority Date: 05/21/2001
• Status: Active Grant

• Current Assignee: Tennant Company
• Original Assignee: Tennant Company
• Inventors: Erko, Robert J., Haeg, John Peter
• Granted Patent: US 7,038,416 B2
• Time in Patent Office: Days
• US Class Current: 318/560
• CPC Class Codes: A47L 11/14 with rotating tools
• CPC Class Codes: A47L 11/283 the tools being disc brushes
• CPC Class Codes: A47L 11/4011 Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor
• CPC Class Codes: A47L 11/4069 Driving or transmission means for the cleaning tools

Abstract

A control system for controlling the work output delivered to a floor surface by a work tool associated with a floor maintenance machine, such as a burnisher, is provided. In one embodiment, a voltage regulator regulates the voltage provided to the motor assembly that drives the work tool. A current sensor monitors the motor current drawn by the motor assembly and provides a signal representative thereof to a controller. The controller also receives as an input a work selector signal representative of a desired level of work output. Based on the work selector signal and the sensed motor current, the controller provides a control signal to an actuator. In response to the control signal, the actuator raises or lowers the work tool relative to the floor as need to control the work output delivered to the floor. In another embodiment, the voltage regulator is omitted, and the controller is configured to generate the control signal based on the product of the motor current and the voltage provided to the motor assembly.

Claims

1. A control system for controlling work output delivered to a floor surface by a rotatable work tool associated with a floor maintenance machine, the control system comprising:

a power source;

a motor assembly coupled to the power source and the rotatable work tool, the motor assembly configured to rotatably drive the rotatable work tool;

a voltage regulator circuit coupled between the power source and the motor assembly, the voltage regulator circuit configured to regulate an output voltage provided by the power source and to provide the regulated output voltage to the motor assembly;

an actuator assembly coupled to the rotatable work tool and configured to adjust contact of the rotatable work tool with the floor surface such that the rotatable work tool delivers a work output to the floor surface;

a current monitor circuit in communication with the motor assembly, the current monitor circuit configured to monitor a motor current to the motor assembly; and

a controller circuit in communication with the current monitor circuit and the actuator assembly, the controller circuit configured to cause the actuator assembly to adjust contact of the rotatable work tool with the floor surface based on the monitored load current and the desired work output, such that the work output delivered to the floor surface is controlled.

2. The control system as recited in claim 1, wherein the controller circuit is in communication with the voltage regulator circuit, and wherein the voltage regulator circuit regulates the output voltage from the power source based on a control signal received from the controller circuit.

3. The control system as recited in claim 2, wherein the controller circuit is configured to monitor the output voltage provided by the power source and to generate the control signal based on the monitored output voltage.

4. The control system as recited in claim 3, wherein the controller circuit is configured to cause the actuator assembly to adjust contact of the rotatable work tool with the floor surface based on the monitored output voltage.

5. The control system as recited in claim 1, wherein the power source comprises a rechargeable battery.

6. The control system as recited in claim 1, comprising a work selector circuit in communication with the controller circuit, wherein the work selector circuit is configured to indicate a selected work output to be delivered to the work surface, and the controller circuit is configured to cause the actuator assembly to adjust contact of the rotatable work tool with the floor surface based on the selected work output.

7. The control system as recited in claim 6, wherein the selected work output is selectable by a user of the floor maintenance machine.

8. A control system to control work output delivered to a floor surface by a rotatable work tool associated with a floor maintenance machine, the control system comprising:

a power source;

a motor assembly coupled to the power source and the rotatable work tool, the motor assembly configured to rotatably drive the rotatable work tool;

an actuator assembly coupled to the rotatable work tool and configured to adjust contact of the rotatable work tool with the floor surface such that the rotatable work tool delivers a work output to the floor surface;

a current monitor circuit in communication with the motor assembly, the current monitor circuit configured to monitor a motor current to the motor assembly;

a voltage monitor circuit in communication with the power source, the voltage monitor circuit configured to monitor an output voltage provided by the power source; and

a controller circuit in communication with the current monitor circuit, the voltage monitor circuit, and the actuator assembly, the controller circuit configured to cause the actuator assembly to adjust contact of the rotatable work tool with the floor surface based on the monitored load current and the monitored output voltage to control the work output delivered to the floor surface.

9. The control system as recited in claim 8, wherein the controller circuit is configured to cause the actuator assembly to adjust contact of the rotatable work tool based on the combination of the monitored load current and the monitored output voltage.

10. The control system as recited in claim 8, comprising a work selector circuit in communication with the controller circuit, wherein the work selector circuit is configured to indicate a selected work output to be delivered to the work surface, and the controller circuit is configured to cause the actuator assembly to adjust contact of the rotatable work tool based on the selected work output.

11. The control system as recited in claim 10, wherein the selected work output is selected by a user of the floor maintenance machine.

12. The control system as recited in claim 8, wherein the power source comprises a rechargeable battery.

14. The method as recited in claim 13, comprising:

selecting a desired work output; and

adjusting contact of the work tool with the floor surface based on the selected desired work output.

15. The method as recited in claim 13, comprising:

monitoring the motor voltage provided by the power source; and

adjusting the regulated motor voltage based on the monitored motor voltage.

16. The method as recited in claim 13, comprising:

monitoring the motor voltage provided by the power source; and

adjusting contact of the work tool with the floor surface based on the selected desired work output.

18. The method as recited in claim 17, comprising:

selecting a desired work output; and

adjusting contact of the work tool with the floor surface based on the selected desired work output.

19. The method as recited in claim 17, comprising:

determining a combination of the provided voltage and the monitored motor current, wherein adjusting contact of the work tool with the floor surface is based on the determined combination.

13. A method of controlling work output delivered to a floor surface by a work tool associated with a floor maintenance machine, the floor maintenance machine including a motor assembly to drive the work tool, the method comprising:

regulating a motor voltage provided by a power source;

providing the regulated motor voltage to the motor assembly;

monitoring a motor current drawn by the motor assembly; and

adjusting contact of the work tool with the floor surface based on the monitored motor current, thereby controlling the work output delivered to the floor surface.

17. A method of controlling work output delivered to a floor surface by a work tool associated with a floor maintenance machine, the floor maintenance machine including a motor assembly to drive the work tool, the method comprising:

providing an input voltage to the motor assembly;

monitoring a motor current drawn by the motor assembly; and

adjusting contact of the work tool with the floor surface based on the input voltage and the monitored motor current, thereby controlling the work output delivered to the floor surface.

20. A method of controlling work output delivered to a floor surface by a work tool associated with a floor maintenance machine, the floor maintenance machine including a motor assembly to drive the work tool, said floor maintenance machine utilizing a rechargeable battery assembly to power the motor assembly, said battery assembly displaying a decreasing output voltage during an operational time frame during which time the machine is powered by a battery charge to perform a floor maintenance operation, the method comprising:

providing an input voltage to the motor assembly from the battery assembly, said input voltage decreasing during the operational time frame;

monitoring a motor current drawn by the motor assembly; and

adjusting contact of the work tool with the floor surface based on the input voltage and the monitored motor current during the operational time frame so that work output delivered to the floor surface by the work tool follows a predetermined curve during the operational time frame.

21. The method as recited in claim 20, comprising:

selecting a desired work output; and

adjusting contact of the work tool with the floor surface based on the selected desired work output.

22. The method as recited in claim 20, comprising:

determining a combination of the provided voltage and the monitored motor current, wherein adjusting contact of the work tool with the floor surface is based on the determined combination.

23. The method as recited in claim 20, wherein the predetermined curve provides for an increasing work output during at least a portion of the operational time frame.

24. The method as recited in claim 20, wherein the predetermined curve provides for a generally constant work output during at least a portion of the operational time frame.

25. The method as recited in claim 20, wherein the predetermined curve provides for a decreasing work output during at least a portion of the operational time frame.