Premixer and gas device

Abstract

A premixer includes a housing having an inner cavity and an air inlet and a gas inlet in communication with the inner cavity, a liner arranged in the inner cavity and having an air flow channel and a gas flow channel in communication with the air inlet and the gas inlet, respectively, and a modulation plate arranged in the inner cavity and coaxially arranged with the liner. The modulation plate has an air outlet in communication with the air flow channel and a gas outlet in communication with the gas flow channel. One of the liner and the modulation plate is configured to rotate coaxially relative to another one of the liner and the modulation plate to modulate a first communication area between the air outlet and the air flow channel and a second communication area between the gas outlet and the gas flow channel.

What is claimed is: 
     
         1 . A premixer comprising:
 a housing having an inner cavity, an air inlet, and a gas inlet, each of the air inlet and the gas inlet being in communication with the inner cavity;   a liner arranged in the inner cavity, the liner having an air flow channel in communication with the air inlet and a gas flow channel in communication with the gas inlet; and   a modulation plate arranged in the inner cavity and coaxially arranged with the liner, the modulation plate having an air outlet in communication with the air flow channel and a gas outlet in communication with the gas flow channel;   wherein one of the liner and the modulation plate is configured to rotate coaxially relative to another one of the liner and the modulation plate to modulate a first communication area between the air outlet and the air flow channel and a second communication area between the gas outlet and the gas flow channel.   
     
     
         2 . The premixer according to  claim 1 , wherein the first communication area is positively correlated with the second communication area. 
     
     
         3 . The premixer according to  claim 2 , wherein the first communication area is greater than the second communication area. 
     
     
         4 . The premixer according to  claim 3 , wherein:
 at least one of the air flow channel or the air outlet has a cross-section with a semi-annular shape; and/or   at least one of the gas flow channel or the gas outlet has a cross-section with a semi-annular shape.   
     
     
         5 . The premixer according to  claim 4 , wherein:
 the air flow channel includes a high-load air flow channel and a low-load air flow channel spaced apart from each other in a circumferential direction of the liner, the cross-section of the air outlet being of a semi-annular shape; and/or   the gas flow channel includes a high-load gas flow channel and a low-load gas flow channel spaced apart from each other in the circumferential direction of the liner, the cross-section of the gas outlet being of a semi-annular shape.   
     
     
         6 . The premixer according to  claim 5 , wherein:
 a circumferential angle of the high-load air flow channel is same as a circumferential angle of the high-load gas flow channel; and/or   the low-load air flow channel and the low-load gas flow channel are spaced apart from each other in a radial direction of the liner.   
     
     
         7 . The premixer according to  claim 5 , wherein the high-load gas flow channel includes at least two gas flow sub-channels arranged at intervals in the circumferential direction of the liner. 
     
     
         8 . The premixer according to  claim 5 , wherein:
 the high-load air flow channel is one of at least two high-load air flow channels of the air flow channel, the low-load air flow channel is one of at least two low-load air flow channels of the air flow channel, and the at least two high-load air flow channels and the at least two low-load air flow channels are arranged in an annular array along a central axis of the liner; and/or   the high-load gas flow channel is one of at least two high-load gas flow channels of the gas flow channel, the low-load gas flow channel is one of at least two low-load gas flow channels of the gas flow channel, and the at least two high-load gas flow channels and the at least two low-load gas flow channels are arranged in an annular array along the central axis of the liner.   
     
     
         9 . The premixer according to  claim 4 , wherein in a radial direction of the liner, the gas flow channel is located outside the air flow channel with respect to a central axis of the liner. 
     
     
         10 . The premixer according to  claim 1 , further comprising:
 a drive assembly connected in a power transmission manner to the modulation plate;   wherein:
 the liner is fixed to the housing; and 
 the drive assembly is configured to drive the modulation plate to rotate relative to the liner. 
   
     
     
         11 . The premixer according to  claim 10 , wherein the drive assembly includes:
 a drive motor arranged at the housing, the drive motor including an output shaft extending into the inner cavity; and   a transmission shaft having an end connected to the output shaft and another end connected to the modulation plate in a power transmission manner.   
     
     
         12 . The premixer according to  claim 11 , wherein:
 the output shaft extends in a radial direction of the liner;   the transmission shaft extends in an axial direction of the liner; and   the output shaft is engaged with the transmission shaft.   
     
     
         13 . The premixer according to  claim 12 , wherein the liner has an avoidance channel extending along a central axis, the transmission shaft passing through the avoidance channel and being in fit with and spaced from the liner. 
     
     
         14 . The premixer according to  claim 13 , wherein a sealing ring is arranged between an outer wall of the transmission shaft and an inner wall of the avoidance channel. 
     
     
         15 . The premixer according to  claim 13 , wherein:
 the liner includes a front liner segment and a rear liner segment that are arranged in an axial direction;   the modulation plate is located at a side of the rear liner segment away from the front liner segment;   the avoidance channel and the gas flow channel are formed at the rear liner segment; and   the front liner segment is engaged with the rear liner segment to form an avoidance groove in communication with the avoidance channel, an end of the output shaft extending into the avoidance groove to be engaged with the transmission shaft.   
     
     
         16 . The premixer according to  claim 15 , wherein a gas retention chamber is formed between an outer side of the rear liner segment and a wall of the inner cavity, the gas inlet being in communication with the gas flow channel through the gas retention chamber. 
     
     
         17 . The premixer according to  claim 1 , wherein one of the liner and the modulation plate has a limit groove, and another one of the liner and the modulation plate is provided with a limit post, the limit post being configured to be engaged with the limit groove to limit a relative rotation angle between the liner and the modulation plate. 
     
     
         18 . A gas device comprising the premixer according to  claim 1 .