Vacuum Cleaner, Controller, and a Method Therefor

Abstract

A method of determining an airflow parameter in a vacuum cleaner comprising a motor-fan assembly comprises receiving one or more signals relating to one or more operational parameters of the motor. The method further comprises determining a torque of a rotatable shaft of the motor based on the one or more operational parameters. The method also comprises determining an airflow parameter based on the determined torque of the rotatable shaft of the motor.

1 . A method of determining an airflow parameter in a vacuum cleaner comprising a motor-fan assembly comprising:
 receiving one or more signals relating to one or more operational parameters of the motor;   determining a torque of a rotatable shaft of the motor based on the one or more operational parameters; and   determining an airflow parameter based on the determined torque of the rotatable shaft of the motor.   
     
     
         2 . The method of  claim 1 , wherein the receiving one or more signals relating to one or more operational parameters comprises receiving one or more signals relating to one or more operational electrical parameters of the motor-fan assembly during operation of the motor-fan assembly. 
     
     
         3 . The method of  claim 2 , wherein the receiving one or more signals comprises receiving a signal relating to the voltage. 
     
     
         4 . The method of  claim 3 , wherein the receiving one or more signals comprises receiving a signal relating to the current. 
     
     
         5 . The method of  claim 4 , wherein the method comprises determining the power based on the received signals relating to the current and the voltage. 
     
     
         6 . The method of  claim 5 , wherein the determining the torque is based on the determined power. 
     
     
         7 . The method of  claim 1 , wherein the method comprises determining the rotational speed of the motor. 
     
     
         8 . The method of  claim 7 , wherein the determining the speed is based on a received signal from a motor rotational speed sensor and/or the motor. 
     
     
         9 . The method of  claim 1 , wherein the method comprises determining one or more other operational parameters of the motor-fan assembly in dependence of the received one or more signals and/or stored parameter information of the motor-fan assembly. 
     
     
         10 . The method of  claim 9 , wherein the determining one or more other operational parameters of the motor-fan assembly comprises determining an efficiency of the motor-fan assembly. 
     
     
         11 . The method of  claim 10 , wherein the determining the efficiency of the motor-fan assembly comprises receiving a stored efficiency parameter for the motor-fan assembly. 
     
     
         12 . The method of  claim 11 , wherein the determining the efficiency of the motor-fan assembly comprises determining the efficiency parameter for one or more actuating variables of the motor-fan assembly. 
     
     
         13 . The method of  claim 10 , wherein the determining the airflow parameter is based on the determined torque and the determined efficiency of the motor-fan assembly. 
     
     
         14 . The method of  claim 13 , wherein the functional relationship between the airflow and the torque is predetermined. 
     
     
         15 . The method of  claim 1 , wherein the method comprises determining that the airflow parameter is below a first threshold value. 
     
     
         16 . The method of  claim 15 , wherein the method comprises issuing an alert to a user in dependence of the determining that the airflow parameter is below the first threshold value. 
     
     
         17 . The method of  claim 15 , wherein the method comprises initiating a filter cleaning procedure in dependence of the determining that the airflow parameter is below the first threshold value. 
     
     
         18 . The method of  claim 17 , wherein the filter cleaning procedure comprises reversing the motor-fan assembly such that the direction of airflow reverses through a filter. 
     
     
         19 . The method of  claim 15 , wherein the method comprises that the airflow parameter is above a second threshold value. 
     
     
         20 . The method of  claim 19 , wherein the method comprises modifying the operational electrical parameters to reduce the airflow flow parameter below the second threshold value. 
     
     
         21 . The method of  claim 1 , wherein the airflow parameter is air velocity. 
     
     
         22 . A vacuum cleaner comprising:
 a motor-fan assembly;   at least one sensor for measuring one or more operational parameters of the motor during operation of the motor-fan assembly;   a controller configured to receiving signals from the at least one sensors, wherein the controller is configured to:
 determine a torque of a rotatable shaft of the motor based on the one or more operational parameters; and 
 determine an airflow parameter based on the determined torque of the rotatable shaft of the motor. 
   
     
     
         23 . A controller for a vacuum cleaner, the controller comprising:
 at least one communication port configured to receiving signals from the at least one sensors, wherein the controller is configured to:
 determine a torque of a rotatable shaft of the motor based on the one or more operational parameters; and 
 determine an airflow parameter based on the determined torque of the rotatable shaft of the motor. 
   
     
     
         24 . A method of controlling a power tool comprising a motor comprising:
 receiving one or more signals relating to one or more operational parameters of the motor;   determining a torque of a rotatable shaft of the motor based on the one or more operational parameters;   determining that the torque of the rotatable shaft of the motor exceeds or drops below a threshold value; and   issuing a control signal to the power tool in dependence of the determined torque exceeding or dropping below the threshold value.