Air convective warmer with noise reduction filter

Abstract

To reduce the noise level of an air convective warmer, the air filter of the warmer is fitted with an air intercept mechanism to disrupt the flow of air that traverses inside the interior cavity of the air filter. By thus disrupting the air flow, the noise that otherwise would have been generated due to a non-interrupted air stream flow is lowered. The air intercept mechanism may be in the form of at least one partition positioned inside the interior cavity of the air filter. Alternatively, double-ended open tubes may be used, so long as the interior cavity of the filter is sealed, with only the tubes providing the passages for air to output from the air filter. Yet a third embodiment of the air reduction filter has an air impermeable material covering at least one portion of the surface area of the filtering material to prevent the inflow air from directly entering into the interior cavity of the air filter through the covered surface area.

1 - 20 . (canceled) 
     
     
         21 . In combination,
 a housing having an air inlet and an air outlet;   a plenum positioned within the housing where air from the inlet flows;   a fan to effect an airflow between the air inlet and the air outlet through the plenum;   an air filter interposed between the air inlet and air outlet for filtering the air input to the plenum due to the movement of the fan; and   an air intercept mechanism within the housing for disrupting the air flow of filtered air in the plenum to reduce the noise level generated by the movement of the fan and the flow of air between the air inlet and the air outlet.   
     
     
         22 . The combination of  claim 21 , wherein the air intercept mechanism comprises at least one partition that disrupts the air flow from the air inlet to the plenum. 
     
     
         23 . The combination of  claim 22 , wherein the air filter has an interior, and wherein the at least one partition is positioned in the interior of the air filter. 
     
     
         24 . The combination of  claim 21 , wherein the air intercept mechanism comprises a plurality of partitions working cooperatively with the air filter to disrupt the air flow into the plenum. 
     
     
         25 . The combination of  claim 21 , wherein the intercept mechanism outputs at least one channeled air flow in the plenum. 
     
     
         26 . The combination of  claim 21 , wherein the intercept mechanism comprises an air impermeable material positioned to disrupt the air flow that passes through the air filter. 
     
     
         27 . The combination of  claim 21 , wherein the fan is positioned within the plenum and is adapted to route the air sucked in from the air inlet to the air outlet to inflate a convective blanket fluidly connected to the air outlet when in operation. 
     
     
         28 . The combination of  claim 21 , further comprising a heater positioned in the housing relative to the plenum to heat the air input from the air inlet. 
     
     
         29 . An air warmer comprising:
 a housing having an air inlet and an air outlet;   a plenum inside the housing in fluid communication with the air inlet and the air outlet;   a fan in the housing when in operation adapted to drawn air from the environment into the plenum via the air inlet and output the air in the plenum as an air stream to the air outlet;   an air filter for filtering input air drawn into the plenum from the environment; and   air intercept means positioned in the path of the input air for disrupting the flow of the air stream traveling in the plenum from the air inlet to the air outlet to reduce the level of nosie resulting from at least the operation of the fan.   
     
     
         30 . The air warmer of  claim 29 , wherein the air intercept means comprises at least one partition that disrupts the flow of air drawn in from the environment through the air filter. 
     
     
         31 . The air warmer of  claim 29 , wherein the air filter comprises an interior, and wherein the at least one partition is positioned in the interior of the air filter. 
     
     
         32 . The air warmer of  claim 29 , wherein the air intercept means comprises a plurality of partitions working cooperatively with the air filter to disrupt the flow of the air stream in the plenum. 
     
     
         33 . The air warmer of  claim 29 , wherein the air intercept means channels at least one air stream of filtered air into the plenum from the filtered air drawn in from the environment. 
     
     
         34 . The air warmer of  claim 29 , wherein the air intercept means comprises an air impermeable material positioned to disrupt the air flow passing through the air filter. 
     
     
         35 . The air warmer of  claim 29 , wherein the fan is positioned within the plenum to route the air drawn in from the air inlet as an air stream to the air outlet for output when the fan is in operation. 
     
     
         36 . In an air warmer having a housing including an air inlet and an air outlet, a plenum within the housing, a fan positioned in the housing adapted to effect an air flow of the air drawn in from the air inlet to the air outlet, a method of reducing at least noise generated by the fan when it is in operation, comprising the steps of:
 a) interposing an air filter in the housing between the air inlet and the air outlet to filter input air drawn through the air inlet from the environment;   b) positioning air intercept means in the path of the input air for disrupting the flow of the air stream in the plenum when the fan is in operation;   whereby the level of nosie resulting from at least the operation of the fan is reduced.   
     
     
         37 . The method of  claim 36 , wherein the step (b) comprising the step of providing at least one partition to disrupt the air flow in the plenum. 
     
     
         38 . The method of  claim 36 , wherein the step (b) comprises channeling at least one air flow from the air filter to the plenum. 
     
     
         39 . The method of  claim 36 , further comprising the steps of:
 positioning the fan within the plenum;   operating the fan to route the air drawn in from the air inlet to the air outlet as an air stream to inflate a convective blanket fluidly connected to the air outlet.   
     
     
         40 . The method of  claim 36 , further comprising the step of:
 positioning a heater in the housing relative to the plenum to heat the air drawn in from the air inlet.