Drainage trapping cartridge and a drainage trapping device for preventing backflow of gas

Abstract

The present invention provides a drainage trapping device which can prevent waste gas or poisonous gas containing bacteria from flowing backwards. The drainage trapping device comprises a water inlet pipe, a drainage trapping cartridge, a water outlet pipe, a float valve and a retaining component. The drainage trapping cartridge is provided with a water outlet which is connected to the water outlet pipe. A lower end of the drainage trapping cartridge is connected with the water inlet pipe. The float valve is disposed inside the drainage trapping cartridge and hermetically engages with a lower part of the drainage trapping cartridge when the drainage trapping cartridge is devoid of water. The retaining component is disposed at the water outlet of the drainage trapping cartridge or in the water outlet pipe, for preventing the float valve from running out.

1 . A drainage trapping device for preventing backflow of gas, the device comprising:
 a water inlet pipe;   a water outlet pipe;   a drainage trapping cartridge defining a water outlet connected to the water outlet pipe, a lower end of the drainage trapping cartridge being connected with the water inlet pipe;   a float valve disposed inside the drainage trapping cartridge, the float valve being configured for hermetically engaging with a lower part of the drainage trapping cartridge when the drainage trapping cartridge is devoid of water, the float valve defining a diameter higher than that of the lower part of the drainage trapping cartridge; and   a retaining component disposed at the water outlet of the drainage trapping cartridge or in the water outlet pipe, the retaining component being configured for preventing the float valve from running out, the retaining component being a block-shaped or rod-shaped component radially projected from inner circumference of the water outlet of the drainage trapping cartridge or the water outlet pipe or being an integral form of an annular component engaged to the drainage trapping cartridge and a block-shaped or rod-shaped component projected from inner circumference of the annular component.   
     
     
         2 . The drainage trapping device of  claim 1 , wherein a gap between an inner tip of the retaining component and a wall of the water outlet of the drainage trapping cartridge and/or between the inner tip of the retaining component and a wall of the water outlet pipe is less than the diameter of the float valve. 
     
     
         3 . The drainage trapping device of  claim 1 , wherein the retaining component is a tapered rod. 
     
     
         4 . The drainage trapping device of  claim 1 , wherein an inner wall of the lower part of the drainage trapping cartridge is provided with a rubber ring. 
     
     
         5 . The drainage trapping device of  claim 1 , wherein the retaining component is disposed at the middle of an upper part of the water outlet of the drainage trapping cartridge or the water outlet pipe. 
     
     
         6 . The drainage trapping device of  claim 1 , wherein a gap is defined between the retaining component and a sidewall of an upper part of the water outlet of the drainage trapping cartridge. 
     
     
         7 . The drainage trapping device of  claim 1 , wherein the lower part of the drainage trapping cartridge is in a funnel shape. 
     
     
         8 . The drainage trapping device of  claim 1 , wherein the float valve is a round ball. 
     
     
         9 . The drainage trapping device of  claim 1 , wherein the water outlet pipe, with the opening tilting up, is mounted on the wall around the water outlet of the drainage trapping cartridge. 
     
     
         10 . A drainage trapping cartridge, comprising:
 a water inlet;   a water outlet, the water outlet being connected to a water outlet pipe;   a float valve disposed inside the drainage trapping cartridge, the float valve being configured for hermetically engaging with a lower part of the drainage trapping cartridge when the drainage trapping cartridge is devoid of water, the float valve defining a diameter higher than that of the lower part of the drainage trapping cartridge; and   a retaining component disposed at the water outlet of the drainage trapping cartridge or in the water outlet pipe, the retaining component being configured for preventing the float valve from running out, the retaining component being a block-shaped or rod-shaped component radially projected from inner circumference of the water outlet of the drainage trapping cartridge or the water outlet pipe or being an integral form of an annular component engaged to the drainage trapping cartridge and a block-shaped or rod-shaped component projected from inner circumference of the annular component.   
     
     
         11 . The drainage trapping cartridge of  claim 10 , wherein a gap between an inner tip of the retaining component and a wall of the water outlet of the drainage trapping cartridge is less than the diameter of the float valve. 
     
     
         12 . The drainage trapping cartridge of  claim 10 , wherein the retaining component is a tapered rod. 
     
     
         13 . The drainage trapping cartridge of  claim 10 , wherein an inner wall of the lower part of the drainage trapping cartridge is provided with a rubber ring. 
     
     
         14 . The drainage trapping cartridge of  claim 10 , wherein the retaining component is disposed at the middle of an upper part of the water outlet of the drainage trapping cartridge or the water outlet pipe. 
     
     
         15 . The drainage trapping cartridge of  claim 10 , wherein a gap is defined between the retaining component and a sidewall of an upper part of the water outlet of the drainage trapping cartridge. 
     
     
         16 . The drainage trapping cartridge of  claim 10 , wherein the lower part of the drainage trapping cartridge is in a funnel shape. 
     
     
         17 . The drainage trapping cartridge of  claim 10 , wherein the float valve is a round ball. 
     
     
         18 . The drainage trapping cartridge of  claim 10 , wherein the water outlet pipe, with the opening tilting up, is mounted on the wall around the water outlet of the drainage trapping cartridge.