Premixing device for water heater and water heater having same

Abstract

A premixing device for a water heater and the water heater having the same are provided. The premixing device for the water heater has a housing and a turning plate. A first airflow passage, a second airflow passage, a first gas passage and a second gas passage are formed in the housing. The turning plate is rotatably disposed on the housing to adjust an opening degree of the first gas passage and an opening degree of the first airflow passage. An air guide hole directly opposite to the first airflow passage is formed on the turning plate.

What is claimed is: 
     
         1 . A premixing device for a water heater, the premixing device comprising:
 a housing, in which a first airflow passage, a second airflow passage, a first gas passage, and a second gas passage are formed; and   a turning plate rotatably disposed on the housing to adjust an opening degree of the first gas passage and an opening degree of the first airflow passage, an air guide hole directly opposite to the first airflow passage being formed on the turning plate.   
     
     
         2 . The premixing device for the water heater according to  claim 1 , wherein the first gas passage is surrounded by the first airflow passage. 
     
     
         3 . The premixing device for the water heater according to  claim 2 , wherein:
 a first support portion is disposed in the housing, the first airflow passage being formed in the first support portion; and   a second support portion is disposed in the first airflow passage, the first gas passage being formed in the second support portion.   
     
     
         4 . The premixing device for the water heater according to  claim 3 , wherein:
 an end surface of a free end of the second support portion and an end surface of a free end of the first support portion are disposed obliquely; and   the turning plate is rotatable to abut against the end surface of the second support portion and/or the end surface of the first support portion.   
     
     
         5 . The premixing device for the water heater according to  claim 4 , wherein the first support portion is inclined in an air flow direction from top to bottom. 
     
     
         6 . The premixing device for the water heater according to  claim 4 , wherein:
 a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion;   a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion; and   an end surface of the third support portion protrudes relative to the end surface of the first support portion.   
     
     
         7 . The premixing device for the water heater according to  claim 6 , wherein:
 a first support rib is disposed between the first support portion and the second support portion; and   a second support rib is disposed between the third support portion and the fourth support portion.   
     
     
         8 . The premixing device for the water heater according to  claim 5 , wherein:
 a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion;   a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion; and   an end surface of the third support portion protrudes relative to the end surface of the first support portion.   
     
     
         9 . The premixing device for the water heater according to  claim 8 , wherein:
 a first support rib is disposed between the first support portion and the second support portion; and   a second support rib is disposed between the third support portion and the fourth support portion.   
     
     
         10 . The premixing device for the water heater according to  claim 1 , further comprising a deflector rib directly opposite to the first gas passage, wherein the deflector rib is disposed on the turning plate. 
     
     
         11 . The premixing device for the water heater according to  claim 1 , wherein a sectional area of the second gas passage is smaller than a sectional area of the first gas passage. 
     
     
         12 . A water heater, comprising a premixing device, the premixing device comprising:
 a housing, in which a first airflow passage, a second airflow passage, a first gas passage, and a second gas passage are formed; and   a turning plate rotatably disposed on the housing to adjust an opening degree of the first gas passage and an opening degree of the first airflow passage, an air guide hole directly opposite to the first airflow passage being formed on the turning plate.   
     
     
         13 . The water heater according to  claim 12 , wherein the first gas passage is surrounded by the first airflow passage. 
     
     
         14 . The water heater according to  claim 13 , wherein:
 a first support portion is disposed in the housing, the first airflow passage being formed in the first support portion; and   a second support portion is disposed in the first airflow passage, the first gas passage being formed in the second support portion.   
     
     
         15 . The water heater according to  claim 14 , wherein:
 an end surface of a free end of the second support portion and an end surface of a free end of the first support portion are disposed obliquely; and   the turning plate is rotatable to abut against the end surface of the second support portion and/or the end surface of the first support portion.   
     
     
         16 . The water heater according to  claim 15 , wherein the first support portion is inclined in an air flow direction from top to bottom. 
     
     
         17 . The water heater according to  claim 15 , wherein:
 a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion;   a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion; and   an end surface of the third support portion protrudes relative to the end surface of the first support portion.   
     
     
         18 . The water heater according to  claim 17 , wherein:
 a first support rib is disposed between the first support portion and the second support portion; and   a second support rib is disposed between the third support portion and the fourth support portion.   
     
     
         19 . The water heater according to  claim 16 , wherein:
 a third support portion is disposed in the housing, a second airflow passage being formed in the third support portion;   a fourth support portion is disposed in the second airflow passage, a second gas passage being formed in the fourth support portion; and   an end surface of the third support portion protrudes relative to the end surface of the first support portion.   
     
     
         20 . The water heater according to  claim 19 , wherein:
 a first support rib is disposed between the first support portion and the second support portion; and   a second support rib is disposed between the third support portion and the fourth support portion.