Humidification of respiratory gases

Abstract

A tub is configured to contain a supply of water and be inserted into a chamber of a humidifier. The tub includes a tub base configured to contain a supply of water and a tub lid connected to the tub base. The tub lid includes an inlet configured to receive a flow of breathable gas to be humidified and an outlet for the humidified flow of breathable gas. The tub further includes a water level indicator configured to indicate a level of the supply of water in the tub base. The water level indicator includes an inclined portion configured to direct the flow of breathable gas from the inlet away from the outlet. The water level indicator may be visible through the inlet.

What is claimed is: 
     
         1 . A tub configured to contain a supply of water and to be coupled to a humidifier, comprising:
 a tub base configured to contain the supply of water;   a tub lid connected to the tub base, the tub lid including an inlet configured to receive a flow of breathable gas to be humidified;   an outlet for the humidified flow of breathable gas; and   a water level indicator configured to indicate a level of the supply of water in the tub base, the water level indicator comprising an inclined portion configured to direct the flow of breathable gas from the inlet away from the outlet.   
     
     
         2 . A tub configured to contain a supply of water and to be coupled to a humidifier, comprising:
 a tub base configured to contain the supply of water;   a tub lid connected to the tub base, the tub lid including an inlet configured to receive a flow of breathable gas to be humidified;   an outlet for the humidified flow of breathable gas; and   a water level indicator configured to indicate a level of the supply of water in the tub base, wherein the water level indicator is visible through the inlet.   
     
     
         3 . A tub according to  claim 2 , wherein the water level indicator comprises an inclined portion. 
     
     
         4 . A tub according to  claim 1 , wherein the water level indicator further comprises a base portion. 
     
     
         5 . A tub according  claim 4 , wherein the inclined portion extends from the base portion. 
     
     
         6 . A tub according to  claim 1 , wherein the water level indicator is coupled to the inlet. 
     
     
         7 . A tub according to  claim 1 , wherein the water level indicator comprises indicia and/or a marking configured to indicate at least a maximum water fill level in the tub base. 
     
     
         8 . A tub according to  claim 7 , wherein the indicia and/or marking is provided on the inclined portion. 
     
     
         9 . A tub according to  claim 1 , wherein the tub lid comprises a channel configured to receive the flow of breathable gas and direct the flow of breathable gas to the inlet, the channel comprising a channel inlet and a channel outlet. 
     
     
         10 . A tub according to  claim 9 , wherein the tub lid comprises a cover portion that covers the channel from the channel inlet to the channel outlet. 
     
     
         11 . A tub according to  claim 9 , wherein the channel is angled upward from the channel inlet to the channel outlet. 
     
     
         12 . A tub according to  claim 9 , wherein the channel outlet is provided in a sump region of the tub lid. 
     
     
         13 . A tub according to  claim 12 , wherein the inlet is provided in the sump region below the channel outlet. 
     
     
         14 . A tub according to  claim 13 , wherein the inlet is provided at a bottom of the sump region and is configured to direct water poured into the sump region into the tub base. 
     
     
         15 . A tub according to  claim 13 , wherein the base portion of the water level indicator is connected to the sump region of the tub lid. 
     
     
         16 . A tub according to  claim 15 , wherein the base portion extends at least partially around the inlet. 
     
     
         17 . A tub according to  claim 16 , wherein the base portion extends half way around the inlet. 
     
     
         18 . A tub according to  claim 1 , wherein the water level indicator is integrally formed with the tub lid. 
     
     
         19 . A tub according to  claim 1 , wherein the tub lid comprises a wall extending from a region adjacent the inlet in a direction away from the outlet to direct the flow of breathable gas away from the outlet. 
     
     
         20 . A tub according to  claim 1 , wherein the inclined portion is angled with respect to a bottom plane of the tub lid at just over 90° to just under 180°.