Patent Publication Number: US-2023146497-A1

Title: Safety-reinforced water-ring vacuum pump including built-in hogging flow path

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a water-ring vacuum pump, and more particularly to a safety-reinforced water-ring vacuum pump including a built-in hogging flow path configured to change an external hogging flow path of the related art to a built-in hogging flow path, thereby making it possible to prevent gas leakage due to pipe breakage and improve the stability and durability of the pump. 
     Description of the Related Art 
     In general, a water-ring vacuum pump includes an eccentrically disposed impeller configured to generate centrifugal force that rotates liquid filled therein using rotational force of the impeller, thereby compressing gas and transporting the same. There are two types of water-ring vacuum pumps, namely a low-pressure vacuum pump in the pressure range near atmospheric pressure such as a vane pump and a Roots pump, and a high-pressure vacuum pump configured to form a gradually higher vacuum from atmospheric pressure through low vacuum pressure to high vacuum pressure. 
     Meanwhile, in consideration of the characteristics of the high-pressure vacuum pump, when a high-pressure vacuum is formed, only a small amount of air can be suctioned compared to a low-pressure vacuum. Accordingly, during low-pressure vacuum operation, the high-pressure vacuum pump performs the function of the low-pressure vacuum pump through a hogging booster pipe in order to bypass a two-stage area in which the high-pressure vacuum is possible. When a certain high vacuum pressure is reached, the high-pressure vacuum pump is passed through the two-stage area rather than bypassing the same by closing a check valve installed in the pipe, thereby performing operation as a high-pressure vacuum pump. 
     However, in the case of a water-ring vacuum pump  100  of the related art, since a hogging pipe  110  is formed as an external type as shown in  FIGS.  1  and  2   , leakage of used gas and pipe interference due to an accident in which the hogging pipe  110  burns may occur during transportation, installation, and operation. 
     Related Art Document 
     Patent Document 
     
         
         (Patent Document 1) KR 2027219 (Registered on Sep. 25, 2019) 
         (Patent Document 2) KR 1694397 (Registered on Jan. 3, 2017) 
         (Patent Document 3) KR 433185 (Registered on May 17, 2004) 
       
    
     SUMMARY OF THE INVENTION 
     Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to change an external hogging booster line of the related art to a built-in hogging booster line, thereby meeting technical requirements according to the characteristics of a check valve and preventing gas leakage due to pipe breakage. 
     In accordance with the present invention, the above and other objects can be accomplished by the provision of a water-ring vacuum pump including a first-stage body including a gas inlet port through which gas is suctioned and a seal water supply port through which seal water is supplied, wherein each of the gas inlet port and the seal water supply port is provided on one side of the first-stage body, a second-stage body including a mixed fluid outlet port through which a mixed fluid of the introduced gas and seal water is discharged, wherein the second-stage body is coupled to the other side of the first-stage body, and an impeller configured to be rotated at high speed by an internal drive shaft penetrating the first-stage body and the second-stage body, wherein the first-stage body has a fluid-mixing space provided therein, wherein the fluid-mixing space has a mixed flow of the gas and the seal water therein, wherein the mixed flow is performed by driving the impeller, and wherein the second-stage body has a fluid guide space and an internal hogging flow path provided therein, wherein the fluid guide space guides a fluid supplied from the fluid-mixing space and the internal hogging flow path communicates with the fluid guide space to guide the mixed fluid to the mixed fluid outlet port. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other objects, features, and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    is an external structural view of a water-ring vacuum pump including an external hogging pipe of the related art; 
         FIG.  2    is a front structural view of the water-ring vacuum pump including the external hogging pipe of the related art; 
         FIG.  3    is an external structural view of a water-ring vacuum pump including a built-in hogging flow path according to an embodiment of the present invention; 
         FIG.  4    is a front structural view of the water-ring vacuum pump of the present invention; 
         FIG.  5    is a plan view of the water-ring vacuum pump of the present invention; 
         FIG.  6    is a side structural view of the water-ring vacuum pump of the present invention; 
         FIG.  7    is a cross-sectional view of the inside of the water-ring vacuum pump of the present invention; 
         FIG.  8    is a view showing mixed fluids being discharged from the water-ring vacuum pump of the present invention; 
         FIG.  9    is an enlarged view of a portion A in  FIG.  8   ; and 
         FIG.  10    is a cross-sectional structural view of a coating state of a hogging flow path according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. 
     Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited to the embodiments described in detail below. The embodiments are provided to more completely describe the present invention to those of ordinary skill in the art. 
     Accordingly, the shapes of components shown in the drawings may be exaggerated to promote a clearer description thereof. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In addition, detailed descriptions of functions and configurations of the known technology determined to unnecessarily obscure the gist of the present invention may be omitted. 
     First, the configuration of a safety-reinforced water-ring vacuum pump including a built-in hogging flow path according to an embodiment of the present invention will be described with reference to the drawings shown in  FIGS.  3  to  9    as follows. 
     The water-ring vacuum pump of the embodiment includes a first-stage body  10  including a gas inlet port  11  through which gas is suctioned and a seal water supply port  12  through which seal water is supplied, wherein each of the gas inlet port  11  and the seal water supply port  12  is provided on one side of the first-stage body  10 , a second-stage body  20  including a mixed fluid outlet port  23  through which a mixed fluid of the introduced gas and seal water is discharged, wherein the second-stage body  20  is coupled to the other side of the first-stage body  10 , and an impeller  40  configured to be rotated at high speed by an internal drive shaft  30  penetrating the first-stage body  10  and the second-stage body  20 . 
     Particularly, in the present invention, the first-stage body  10  has a fluid-mixing space  13  provided therein. Here, the fluid-mixing space  13  has a mixed flow of the gas and the seal water therein, and the mixed flow is performed by driving the impeller  40 . Further, the second-stage body  20  has a fluid guide space  21  and an internal hogging flow path  22  respectively provided therein. Here, the fluid guide space  21  guides the fluid supplied from the fluid-mixing space  13  and the internal hogging flow path  22  communicates with the fluid guide space  21  to guide the mixed fluid to the mixed fluid outlet port  23 . 
     Additionally, in the second-stage body  20 , any one of a plate check valve  26  made of titanium and a ball check valve  27  made of titanium may be optionally formed between the fluid guide space  21  and the internal hogging flow path  22 , or the plate check valve  26  and the ball check valve  27  may be formed together therebetween. Here, the plate check valve  26  and the ball check valve  27  limit fluid movement therebetween. 
     In this case, the plate check valve  26  forms a plate shape configured to open and close a distribution hole  26   a  formed between the fluid guide space  21  and the internal hogging flow path  22 , and the ball check valve  27  is formed to be movable upwards and downwards with respect to a guide pipe  28  having a plurality of distribution holes  28   a  formed therein. Here, a separation prevention part  29  configured to prevent separation of the ball check valve  27  is coupled to the upper portion of the guide pipe  28 . 
     Meanwhile, in this embodiment, the water-ring vacuum pump has a partition wall  16  formed therein. Here, the partition wall  16  partitions the first-stage body  10  from the second-stage body  20 . Further, a distribution hole  17  configured to connect the fluid-mixing space  13  to the fluid guide space  21  is formed in the lower portion of the partition wall  16 . 
     In the drawings, reference numerals  15  and  25 , which are not described herein, respectively represent a first stage cone and a second stage cone. 
     Action effects according to the operation of the water-ring vacuum pump including the built-in hogging flow path of the present invention having such a configuration will be described. 
     The water-ring vacuum pump in this embodiment has a two-stage structure suitable for high-pressure vacuum operation, and has a characteristic of minimizing the time to reach a vacuum strength required by a customer from atmospheric pressure. 
     Here, in the present invention, since a hogging flow path configured to guide a fluid to the mixed fluid outlet port  23  is formed as the internal hogging flow path  22  instead of the external structure of the related art, the mixed fluid of gas and seal water, which are mixed in the fluid-mixing space  13  in the first-stage body  10 , is guided to the internal hogging flow path  22  through the fluid guide space  21  of the second-stage body  20 . 
     Particularly, since the plate check valve  26  or the ball check valve  27  is formed between the fluid guide space  21  and the internal hogging flow path  22 , it is possible to stably control the flow of the fluid according to the characteristics of each check valve depending on the vacuum strength and the fluid pressure. 
     In addition, it is possible to more smoothly perform internal guidance of the fluid through the distribution hole  17  formed in the lower portion of the partition wall  16 . 
     Therefore, in the safety-reinforced water-ring vacuum pump of the present invention, a flow path having a hogging booster function is formed as a built-in type, thereby having an effect of preventing damage and gas leakage due to the external structure of the related art and thus improving stability and durability. 
     Meanwhile,  FIG.  10    is a view showing the configuration of a water-ring pump according to another embodiment of the present invention. Here, the inner wall surface of the internal hogging flow path  22  is coated with a hogging coating layer  22   a  configured to reduce frictional force with a fluid. 
     In this case, the hogging coating layer  22   a  may preferably form a mixed composition containing 40 to 60 wt% of amino resin, 15 to 30 wt% of polyoxyethylene, 10 to 20 wt% of sodium hydroxide, 1 to 15 wt% of α-benzyl acrylic acid, 1 to 10 wt% of propylene glycol, and 1 to 10 wt% of phenoxyethanol. 
     When the hogging coating layer  22   a  is formed as described above, the frictional force of the fluid discharged to the mixed fluid outlet port  23  through the internal hogging flow path  22  is reduced, thereby making it possible to improve noise reduction and discharge efficiency. 
     Particularly, since a polyoxyethylene component is mixed in the hogging coating layer  22   a , the surface lubricity of the coating layer is improved, sodium hydroxide, which is a strong basic aqueous solution, prevents discoloration and deterioration of the hogging coating layer  22   a , and α-benzyl acrylic acid allows the coating layer according to the catalytic action of amino resin to be formed to a uniform thickness overall. In addition, each of the additionally added propylene glycol and phenoxyethanol has an effect of improving the durability of the hogging coating layer  22   a  and preventing cracks in the coating surface due to changes in the internal pressure in the vacuum atmosphere. 
     As is apparent from the above description, a water-ring vacuum pump of the present invention includes a built-in flow path having a hogging booster function, thereby having an effect of preventing damage and gas leakage due to the external structure of the related art and thus improving stability and durability. 
     Further, a plate check valve system and a ball check valve system are applied to the water-ring vacuum pump, thereby making it possible to secure stability of fluid movement according to the characteristics of a check valve, durability, and selection of appropriate material. 
     Although preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that the water-ring vacuum pump structure of the present invention can be modified in various ways. 
     However, such modifications should not be understood as being separate from the technical spirit or scope of the present invention, and such modifications should be included within the scope of the appended claims of the present invention.