Haircare appliance

Abstract

A haircare appliance includes a pressure sensor for generating a pressure signal indicative of air pressure within an airflow path, the pressure sensor being upstream of an airflow generator. A controller is configured to estimate, based at least partly on the pressure signal, a blockage factor corresponding to an amount by which the airflow path is blocked. When the estimated blockage factor exceeds a blockage warning threshold, a warning indicative of a partial blockage is output. When the estimated blockage factor exceeds a critical threshold, the critical threshold being higher than the blockage warning threshold, a power output of at least one component of the haircare appliance is turned off or reduced.

1 . A haircare appliance comprising:
 an airflow path, the airflow path having disposed within it:   an airflow generator for moving air downstream through the airflow path; and   a pressure sensor for generating a pressure signal indicative of air pressure within the airflow path, the pressure sensor being upstream of the airflow generator; and   a controller configured to:   receive the pressure signal;   estimate, based at least partly on the pressure signal, a blockage factor corresponding to an amount by which the airflow path is blocked;   when the estimated blockage factor exceeds a blockage warning threshold, output a warning indicative of a partial blockage; and   when the estimated blockage factor exceeds a critical threshold, the critical threshold being higher than the blockage warning threshold, turn off or reduce a power output of at least one component of the haircare appliance.   
     
     
         2 . The haircare appliance of  claim 1 , including an air filter for filtering air entering the airflow path, the amount by which the airflow path is blocked at least partly comprising an amount by which the filter is blocked. 
     
     
         3 . The haircare appliance of  claim 1 , wherein the controller is configured to:
 based on the pressure signal, determine an ambient air pressure prior to the airflow generator reaching an operating speed   based on the pressure signal, determine a dynamic air pressure after the airflow generator reaches the operating speed; and   estimate the blockage factor at least partly based on a difference between the ambient pressure and the dynamic air pressure.   
     
     
         4 . The haircare appliance of  claim 3 , wherein the controller is configured to determine the ambient air pressure prior to a drive signal being supplied to the airflow generator. 
     
     
         5 . The haircare appliance of  claim 1 , wherein:
 the haircare appliance has at least two selectable settings that control at least a rate at which the airflow generator moves air through the airflow path; and   the controller is configured to:   receive information indicative of a currently selected setting; and   estimate the blockage factor at least partly based on the received information indicative of a currently selected setting.   
     
     
         6 . The haircare appliance of  claim 5 , wherein turning off or reducing a power output of at least one component of the haircare appliance comprises turning off or reducing a power output of the airflow generator. 
     
     
         7 . The haircare appliance of  claim 1 , including an accessory capable of being removably attached at or adjacent to an outlet of the airflow path, attachment of the accessory causing a change in characteristic of the airflow as it exits the airflow path, wherein the controller is configured to estimate the blockage factor at least partly taking into account an impact of the change in airflow characteristic caused when the airflow accessory is attached. 
     
     
         8 . The haircare appliance of  claim 7 , wherein the controller is configured to:
 identify an airflow accessory that is attached; and   determine, based the identified airflow accessory, a correction factor for use in estimating the blockage factor.   
     
     
         9 . The haircare appliance of  claim 8 , wherein the controller is configured to look up, in a memory, the correction factor, based on the identified accessory. 
     
     
         10 . The haircare appliance of  claim 7 , comprising a sensor for identifying the airflow accessory that is attached. 
     
     
         11 . The haircare appliance of  claim 7 , wherein the correction factor is stored by the accessory, and the controller is configured to read the correction factor from the accessory. 
     
     
         12 . A method comprising:
 generating a pressure signal indicative of air pressure within an airflow path of a haircare appliance upstream of an airflow generator;   estimating, based at least partly on the pressure signal, a blockage factor corresponding to an amount by which the airflow path is blocked;   when the estimated blockage factor exceeds a blockage warning threshold, outputting a warning indicative of a partial blockage; and   when the estimated blockage factor exceeds a critical threshold, the critical threshold being higher than the blockage warning threshold, turning off or reducing a power output of at least one component of the haircare appliance.   
     
     
         13 . The method of  claim 12 , the amount by which the airflow path is blocked at least partly comprising an amount by which an air filter in the airflow path is blocked. 
     
     
         14 . The method of  claim 12 , comprising:
 based on the pressure signal, determining an ambient air pressure prior to the airflow generator reaching an operating speed;   based on the pressure signal, determining a dynamic air pressure after the airflow generator reaches the operating speed; and   estimating the blockage factor at least partly based on a difference between the ambient pressure and the dynamic air pressure.   
     
     
         15 . The method of  claim 14 , comprising determining the ambient air pressure prior to a drive signal being supplied to the airflow generator. 
     
     
         16 . The method of  claim 12 , wherein the haircare appliance has at least two selectable settings that control at least a rate at which the airflow generator moves air through the airflow path, the method comprising:
 receiving information indicative of a currently selected setting; and   estimating the blockage factor at least partly based on the received information indicative of a currently selected setting.   
     
     
         17 . The method of  claim 16 , wherein turning off or reducing a power output of at least one component of the haircare appliance comprises turning off or reducing a power output of the airflow generator. 
     
     
         18 . The method of  claim 12 , wherein the haircare appliance includes an accessory capable of being removably attached at or adjacent to an outlet of the airflow path, attachment of the accessory causing a change in characteristic of the airflow as it exits the airflow path, the method comprising estimating the blockage factor at least partly taking into account an impact of the change in airflow characteristic caused when the airflow accessory is attached. 
     
     
         19 . The method of  claim 18 , comprising:
 identifying an airflow accessory that is attached; and   determining, based the identified airflow accessory, a correction factor for use in estimating the blockage factor.   
     
     
         20 . The method of  claim 19 , comprising looking up, in a memory, the correction factor, based on the identified accessory. 
     
     
         21 . The method of  claim 18 , comprising using a sensor to identify the airflow accessory that is attached. 
     
     
         22 . The method of  claim 18 , wherein the correction factor is stored by the accessory, and the method comprising reading the correction factor from the accessory. 
     
     
         23 . A haircare appliance comprising:
 an airflow path, the airflow path having disposed within it:   an airflow generator for moving air downstream through the airflow path; and   a pressure sensor for generating a pressure signal indicative of air pressure within the airflow path, the pressure sensor being upstream of the airflow generator; and   a controller configured to:   receive the pressure signal;   determine, based at least partly on the pressure signal, that the airflow generator is operating incorrectly to cause the air to move upstream; and   upon determining that the airflow generator is operating incorrectly to cause the air to move upstream, stop the airflow generator.   
     
     
         24 . A method comprising:
 generating a pressure signal indicative of air pressure within an airflow path of a haircare appliance upstream of an airflow generator;   determining, based at least partly on the pressure signal, that the airflow generator is operating incorrectly to cause the air to move upstream; and   upon determining that the airflow generator is operating incorrectly to cause the air to move upstream, stopping the airflow generator.   
     
     
         25 . A haircare appliance comprising:
 an airflow path, the airflow path having disposed within it:   an airflow generator for moving air downstream through the airflow path; and   a pressure sensor for generating a pressure signal indicative of air pressure within the airflow path, the pressure sensor being disposed upstream of the airflow generator; and   a controller configured to, while the airflow generator is active to move the air downstream through the airflow path:   receive the pressure signal;   identify, based at least partly on the pressure signal, a drop in air pressure within the airflow path;   determine, based at least partly on the identified drop in air pressure, that there is an at least partial blockage of an outlet of the airflow path; and   upon determining that there is an at least partial blockage of an outlet:   turning off or reducing a power output of at least one component of the haircare appliance; or   outputting a warning indicative of the at least partial blockage of the outlet.   
     
     
         26 . A method performed by a haircare appliance, the method comprising:
 generating a pressure signal indicative of air pressure within an airflow path of the haircare appliance upstream of an airflow generator;   identifying, based at least partly on the pressure signal, a drop in air pressure within the airflow path;   determining, based at least partly on the identified drop in air pressure, that there is an at least partial blockage of an outlet of the airflow path; and   upon determining that there is an at least partial blockage of an outlet:   turning off or reducing a power output of at least one component of the haircare appliance; or   outputting a warning indicative of the at least partial blockage of the outlet.   
     
     
         27 . A haircare appliance comprising:
 an airflow path, the airflow path having disposed within it:   an airflow generator for moving air downstream through the airflow path; and   a pressure sensor for generating a pressure signal indicative of air pressure within the airflow path; and   an accessory capable of being removably attached at or adjacent to an outlet of the airflow path, attachment of the accessory causing a change in a characteristic of the airflow as it exits the airflow path;   a controller configured to:   receive the pressure signal;   identify, based at least partly on the pressure signal, a change in air pressure within the airflow path; and   determine, based at least partly on the identified change in air pressure, that the accessory has been detached.   
     
     
         28 . A method performed by a haircare appliance, the haircare appliance comprising an accessory capable of being removably attached at or adjacent to an outlet of the airflow path, attachment of the accessory causing a change in a characteristic of the airflow as it exits the airflow path the method comprising:
 generating a pressure signal indicative of air pressure within an airflow path of the haircare appliance upstream of an airflow generator;   identifying, based at least partly on the pressure signal, a change in air pressure within the airflow path;   determining, based at least partly on the identified change in air pressure, that the accessory has been detached.   
     
     
         29 . A haircare appliance comprising an airflow path, the airflow path having disposed within it:
 a pressure sensor for generating a pressure signal indicative of air pressure within the airflow path;   an airflow generator for moving air downstream through the airflow path;   a heater for heating the air; and   a temperature sensor for generating a temperature signal indicative of a temperature of air heated by the heater;   the haircare appliance including a controller configured to receive at least the pressure signal and the temperature signal, and configured to:   estimate, based at least partly on the pressure signal, a blockage factor corresponding to an amount by which the airflow path is blocked;   calculate a temperature correction factor to apply to the temperature signal, based on at least the blockage factor.   
     
     
         30 . A method of determining a temperature correction factor to apply to a temperature signal generated by a temperature sensor downstream of a heater within an airflow path of a haircare appliance, the temperature signal being indicative of a temperature of air heated by the heater, the method comprising:
 estimating, based at least partly on a pressure signal indicative of air pressure within the airflow path, a blockage factor corresponding to an amount by which the airflow path is blocked; and   calculating a temperature correction factor to apply to the temperature signal, based on at least the blockage factor.   
     
     
         31 . A haircare appliance comprising a barometer chip for measuring air pressure, the barometer chip having a power supply input and an enable input, the power supply input and the enable input being electrically coupled to a signal line, such that a control signal appearing on the signal line both powers up and enables the barometer chip.