Pressure boosting device and gas water heater

Abstract

A housing having a water inlet and a water outlet, a plurality of impellers located between the water inlet and the water outlet, and a driver disposed at the housing and engaged with the plurality of impellers. The plurality of impellers are arranged at intervals along an axis direction of each impeller. The driver is configured to drive the plurality of impellers to rotate.

What is claimed is: 
     
         1 . A pressure boosting device comprising:
 a housing having a water inlet and a water outlet;   a plurality of impellers located between the water inlet and the water outlet, the plurality of impellers being arranged at intervals along an axis direction of each impeller; and   a driver disposed at the housing and engaged with the plurality of impellers, the driver being configured to drive the plurality of impellers to rotate.   
     
     
         2 . The pressure boosting device according to  claim 1 , further comprising:
 a water guide component disposed between two adjacent impellers of the plurality of impellers, the water guide component being configured to guide water from an outlet of an upstream one of the two adjacent impellers to an inlet of a downstream one of the two adjacent impellers in a water flowing direction.   
     
     
         3 . The pressure boosting device according to  claim 2 , wherein:
 each of the plurality of impellers has an impeller inlet located at a central part of the impeller and an impeller outlet located at a periphery of the impeller;   the water guide component has a water guide inlet and a water guide outlet; and   in a radial direction of the impeller, the water guide inlet is located outside the impeller outlet, and the water guide outlet is located inside the water guide inlet and corresponds to the impeller inlet.   
     
     
         4 . The pressure boosting device according to  claim 1 , wherein each of the plurality of impellers has an axis perpendicular to a centerline of the water inlet. 
     
     
         5 . The pressure boosting device according to  claim 4 , wherein:
 the centerline of the water inlet extends vertically; and   the axis of the impeller extends horizontally.   
     
     
         6 . The pressure boosting device according to  claim 1 , wherein:
 the water inlet is located below the water outlet; and   a centerline of the water inlet is parallel to a centerline of the water outlet.   
     
     
         7 . The pressure boosting device according to  claim 1 , wherein the housing has a water inflow passage between the water inlet and the plurality of impellers, and a flow cross-sectional area of at least a portion of the water inflow passage gradually increases in a direction towards the plurality of impellers. 
     
     
         8 . The pressure boosting device according to  claim 7 , wherein the housing has a water outflow passage between the plurality of impellers and the water outlet, and a flow cross-sectional area of at least a portion of the water outflow passage gradually increases in a direction towards the water outflowing opening. 
     
     
         9 . The pressure boosting device according to  claim 1 , wherein each of the plurality of impellers includes:
 a first cover plate having an opening at a central part of the first cover plate;   a second cover plate including a connection part at a central part of the second cover plate, the connection part cooperating with the driver; and   a blade between the first cover plate and the second cover plate.   
     
     
         10 . The pressure boosting device according to  claim 9 , wherein:
 at least part of the connection part protrudes beyond a side of the second cover plate facing towards the first cover plate; and   a part of the connection part extends into the opening, an impeller inlet being formed between the part of the connection part and an inner peripheral surface of the first cover plate.   
     
     
         11 . The pressure boosting device according to  claim 9 , wherein:
 the connection part has an annular shape, and has an engagement groove at an inner peripheral surface of the connection part, the engagement groove penetrating the connection part along the axis direction of the impeller; and   the driver includes a drive shaft with a key, the key being inserted in and engaged with the engagement groove.   
     
     
         12 . The pressure boosting device according to  claim 9 , wherein:
 the second cover plate has a blade groove engaged with the blade, the blade being configured to be inserted in the blade groove;   the blade groove has a slot at a bottom wall of the blade groove;   the blade includes a protrusion protruding towards the second cover plate and configured to be inserted in the first slot;   the blade and the first cover plate are integrally formed; and   the second cover plate is an integrated member.   
     
     
         13 . The pressure boosting device according to  claim 9 , wherein the blade is one of a plurality of blades that include first blades and second blades that are alternately arranged in a circumferential direction of the impeller, a length of each of the first blades being different from a length of each of the second blades. 
     
     
         14 . The pressure boosting device according to  claim 13 , wherein:
 in a radial direction of the impeller, an outer end of one first blade of the first blades extends to an outer peripheral edge of the first cover plate, and an inner end of the one first blade extends to a position inside an inner peripheral edge of the first cover plate and abuts against the connection part; and   two ends of one of the second blade are located between the outer circumferential edge and the inner peripheral edge of the first cover plate.   
     
     
         15 . The pressure boosting device according to  claim 13 , wherein:
 in a radial direction of the impeller, outer ends of the first blades and outer ends of the second blades are arranged at equal intervals in the circumferential direction of the impeller; and   an inner end of one second blade of the second blades is offset from a center between two of the first blades adjacent to the one second blade.   
     
     
         16 . The pressure boosting device according to  claim 1 , further comprising:
 a water guide component disposed between two adjacent impellers of the plurality of impellers and including:
 a water guide vane; 
 a water guide hood having a water guide inlet; and 
 a water guide base having a water guide outlet; 
   wherein:
 the water guide hood is disposed at a side of the water guide base adjacent to an upstream one of the two adjacent impellers in a water flowing direction, and the water guide vane is disposed between the water guide hood and the water guide base; 
 the housing has a chamber, one of the water guide hood and the water guide base being fixedly connected to the housing, and an outer peripheral wall of another one of the water guide hood and the water guide base outer abutting against a wall surface of the chamber. 
   
     
     
         17 . The pressure boosting device according to  claim 16 , wherein:
 the water guide vane is formed at the water guide hood, and includes a protrusion protruding towards the water guide base;   the water guide base has a water guide vane groove;   the water guide vane is configured to be inserted in the water guide vane groove;   the water guide vane groove has a slot at a bottom wall of the water guide vane groove; and   the protrusion is configured to be inserted in the slot.   
     
     
         18 . The pressure boosting device according to  claim 16 , wherein the water guide hood includes:
 a water guide hood plate having an avoidance opening at a central part of the water guide hood plate;   a retaining ring disposed at a side of the water guide hood plate adjacent to the water guide base and abutting against the wall surface of the chamber;   one end of the water guide vane is connected to the retaining ring and another end of the water guide vane extends to the central part of the water guide hood plate; and   the water guide inlet is located between the water guide vane and the retaining ring.   
     
     
         19 . The pressure boosting device according to  claim 18 , wherein a dimension of the water guide inlet gradually increases in a water guide direction of the water guide component. 
     
     
         20 . A gas water heater comprising:
 a pressure boosting device including;
 a housing having a water inlet and a water outlet; 
 a plurality of impellers located between the water inlet and the water outlet, the plurality of impellers being arranged at intervals along an axis direction of each impeller; and 
 a driver disposed at the housing and engaged with the plurality of impellers, the driver being configured to drive the plurality of impellers to rotate.