The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 07, 2017
Filed:
Sep. 10, 2007
David John Hawker, Malmesbury, GB;
George Francis Paul Oakham, Malmesbury, GB;
David John Hawker, Malmesbury, GB;
George Francis Paul Oakham, Malmesbury, GB;
Dyson Technology Limited, Malmesbury, Wiltshire, GB;
Abstract
A motor driving apparatus for a cleaning appliance includes a battery source and a power controller. The battery source supplies the power controller with an output having a first voltage which decreases as the battery source is discharged. The power controller modulates the output to produce a drive signal for driving a motor that has a second voltage and a variable duty cycle. The power controller increases the duty cycle of the drive signal as the first voltage decreases in order to maintain the second voltage at a substantially constant average value per unit time. By providing the above arrangement, the motor can be supplied with a constant voltage throughout the available run time of the battery. When forming part of a cleaning appliance having a motor, the above arrangement allows the motor to operate at a substantially constant speed throughout the run time of the battery.