Hair dryer capable of increasing air flow rate based on negative-pressure flow increasing structure

Abstract

A hair dryer capable of increasing an air flow rate based on a negative-pressure flow increasing structure is provided, which belongs to the technical field of hair dryers. The hair dryer includes an air duct part and a handle part docked to the air duct part. The air duct part has an annular cavity and a mixing cavity. A main air outlet is provided in a front end of the mixing cavity; a flow-increasing air inlet is provided in a rear end of the mixing cavity. A main air inlet is provided in a lower end of the handle part. An upper end of the handle part is communicated with the annular cavity, so that a longitudinal fluid flow passage from the main air inlet to the annular cavity is formed inside the handle part. A boosting unit is arranged inside the longitudinal fluid flow passage.

What is claimed is: 
     
         1 . A hair dryer capable of increasing an air flow rate based on a negative-pressure flow increasing structure, comprising an air duct part ( 10 ) and a handle part ( 20 ) docked to the air duct part ( 10 ), wherein the air duct part ( 10 ) has an annular cavity ( 11 ), a mixing cavity ( 12 ), and a plurality of stages of annular rings ( 30 ); a main air outlet ( 13 ) is provided in a front end of the mixing cavity ( 12 ); a flow-increasing air inlet ( 14 ) is provided in a rear end of the mixing cavity ( 12 ); a main air inlet ( 21 ) is provided in a lower end of the handle part ( 20 ); an upper end of the handle part ( 20 ) is communicated with the annular cavity ( 11 ), so that a longitudinal fluid flow passage from the main air inlet ( 21 ) to the annular cavity ( 11 ) is formed inside the handle part ( 20 ); a boosting unit ( 22 ) is arranged inside the longitudinal fluid flow passage; a heating unit ( 15 ) is arranged at a middle section of the mixing cavity ( 12 );
 the plurality of stages of annular rings ( 30 ) are arranged between the annular cavity ( 11 ) and the mixing cavity ( 12 ); two adjacent stages of annular rings ( 30 ) form a ring nozzle ( 31 ) communicated to the annular cavity ( 11 ) and the mixing cavity ( 12 ); the ring nozzle ( 31 ) faces the main air outlet ( 13 ); a curved bulge ( 32 ) inwards extending along the annular cavity ( 11 ) is formed on each annular ring ( 30 ) located in front of each ring nozzle ( 31 ), so that the ring nozzle ( 31 ) forms a curved transition structure from the annular cavity ( 11 ) to the mixing cavity ( 12 ); and   the main air inlet ( 21 ), the longitudinal fluid flow passage, the boosting unit ( 22 ), the annular cavity ( 11 ), and the ring nozzles ( 31 ) form the negative-pressure flow increasing structure to generate, in the mixing cavity ( 12 ), the flow-increasing air flow that enters along the flow-increasing air inlet ( 14 ) and then exits through the main air outlet ( 13 ).   
     
     
         2 . The hair dryer capable of increasing the air flow rate based on the negative-pressure flow increasing structure according to  claim 1 , wherein the annular cavity ( 11 ) has a flow guide cavity ( 111 ) with a tapered outer side and a transition cavity ( 112 ) docked to the flow guide cavity ( 111 ); the outer side of the flow guide cavity ( 111 ) forms an angle of 30° to 45° with a horizontal direction; an inner side of the flow guide cavity ( 111 ) is composed of the plurality of stages of annular rings ( 30 ); the plurality of stages of annular rings ( 30 ) are in a steplike shape from front to back and have inner diameters that gradually decrease; and the transition cavity ( 112 ) is communicated to an inside of the handle part ( 20 ). 
     
     
         3 . The hair dryer capable of increasing the air flow rate based on the negative-pressure flow increasing structure according to  claim 2 , wherein the outer side of the flow guide cavity ( 111 ) and the last stage of annular ring ( 30 ) form a curved transition at a rear end and are set as the flow-increasing air inlet ( 14 ). 
     
     
         4 . The hair dryer capable of increasing the air flow rate based on the negative-pressure flow increasing structure according to  claim 1 , wherein a spacing between two adjacent stages of annular rings ( 30 ) is 0.4 mm to 1 mm. 
     
     
         5 . The hair dryer capable of increasing the air flow rate based on the negative-pressure flow increasing structure according to  claim 2 , wherein the transition cavity ( 112 ) is a horizontally arranged cavity structure; a cross-sectional area S 12  of the transition cavity is set to be larger than a cross-sectional area S 11  of the handle part ( 20 ); and a transverse length L 12  of the transition cavity ( 112 ) is greater than 1.5 times to 2.5 times an inner diameter D 11  of the handle part ( 20 ). 
     
     
         6 . The hair dryer capable of increasing the air flow rate based on the negative-pressure flow increasing structure according to  claim 5 , wherein a cross-sectional area S 21  of the flow-increasing air inlet ( 14 ) is set to be smaller than a cross-sectional area S 24  of the main air outlet ( 13 ). 
     
     
         7 . The hair dryer capable of increasing the air flow rate based on the negative-pressure flow increasing structure according to  claim 1 , wherein the heating unit ( 15 ) is arranged between the main air outlet ( 13 ) and the ring nozzles ( 31 ), and a distance is reserved between the heating unit ( 15 ) and the ring nozzles ( 31 ) to allow fluids entering the mixing cavity ( 12 ) from the ring nozzles ( 31 ) and the flow-increasing air outlet ( 14 ) to be fully mixed. 
     
     
         8 . The hair dryer capable of increasing the air flow rate based on the negative-pressure flow increasing structure according to  claim 1 , wherein a connection point ( 33 ) is arranged between two adjacent stages of annular rings ( 30 ), and the two adjacent stages of annular rings ( 30 ) are connected through the connection point ( 33 ).