Patent Publication Number: US-2022228784-A1

Title: Electronic Expansion Valve

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present disclosure claims priority to Chinese patent application No. 201910508067.9, titled “Electronic Expansion Valve”, and filed to China National Intellectual Property Administration on Jun. 12, 2019. 
     TECHNICAL FIELD 
     The present disclosure relates to the technical field of electronic expansion valves, and in particular, to an electronic expansion valve. 
     BACKGROUND 
     At present, an electronic expansion valve includes a housing and a valve core assembly, the valve core assembly is disposed in a valve body. The housing includes an accommodating cavity and a valve cavity, wherein the valve cavity is used for communicating with a pipeline, and the valve core assembly moves in the housing, so as to adjust the communication situation between the valve cavity and the pipeline, thereby achieving opening and closing of the electronic expansion valve. 
     However, in the art known to inventors, the accommodating cavity is not in communication with the valve cavity, and when the valve core assembly is used to open or close the electronic expansion valve, a pressure difference exists between the accommodating cavity and the valve cavity, thereby affecting the action performance of the valve core assembly. Therefore, there is a problem in the art known to inventors that it is difficult to achieve rapid pressure balance. 
     SUMMARY 
     Some embodiments of the present disclosure provide an electronic expansion valve, to solve the problem in the art known to inventors that it is difficult to achieve rapid pressure balance. 
     Some embodiments of the present disclosure provide an electronic expansion valve, the electronic expansion valve includes: a housing, wherein the housing is provided with an accommodating cavity and a valve cavity, the accommodating cavity is spaced apart from the valve cavity, the valve cavity is used for, communicating with a pipeline, the housing includes a valve seat, and the valve cavity is disposed in the valve seat; a valve core assembly, movably disposed in the housing, wherein the valve core assembly has an open position and a blocking position, when the valve core assembly is located in the open position, the valve cavity is in a communication state, and when the valve core assembly is located in the blocking position, the valve cavity is in an isolation state; and a guide seat, disposed in the housing, wherein the guide seat is located between the accommodating cavity and the valve cavity, the valve core assembly partially penetrates into the guide seat, a balance channel is provided between the guide seat and the valve seat, one end of the balance channel is in communication with the accommodating cavity, and the other end of the balance channel is in communication with the valve cavity. 
     In some embodiments, the housing further includes a sleeve, the valve seat is connected with the sleeve, a mounting hole is disposed at an end, close to the sleeve, of the valve seat, the mounting hole is in communication with the interior of the sleeve to form the accommodating cavity, the valve cavity is disposed at the other end of the valve seat, and one end of the guide seat is fixedly connected with the valve seat through the mounting hole. 
     In some embodiments, the valve core assembly includes a nut seat and a screw penetrating into the nut seat, the other end of the guide seat is connected with the nut seat, and an outer wall of the guide seat is in transition fit or interference fit with an inner hole of the nut seat, thereby guiding the nut seat, and improving a coaxiality of the nut seat, the screw and the valve seat. 
     In some embodiments, the mounting hole is a stepped hole, the mounting hole includes a first hole and a second hole which are sequentially provided and have sequentially decreasing hole diameters, and the second hole is in communication with the valve cavity. 
     In some embodiments, a limiting boss is disposed on the outer wall of the guide seat, the limiting boss is in interference fit with the first hole, the limiting boss is used for limiting a relative position between the guide seat and the valve seat, and the guide seat penetrates into the first hole and the second hole. 
     In some embodiments, the balance channel includes a notch, the notch is disposed on a side wall of the limiting boss, and the accommodating cavity is in communication with the valve cavity by means of the notch. 
     In some embodiments, the limiting boss includes a first boss and a second boss which are disposed in a stepped manner, the first boss is disposed corresponding to the first hole, the second boss is disposed corresponding to the second hole, and the notch penetrates through the first boss and the second boss. 
     In some embodiments, a plurality of notches are disposed on the side wall of the guide seat, and the plurality of notches are disposed at intervals along a circumferential direction of the limiting boss. 
     In some embodiments, the guide seat and/or the valve seat are provided with communicating holes, one end of each communicating hole is in communication with the accommodating cavity, the other end of the each communicating hole is in communication with the valve cavity, and the communicating holes form the balance channel. 
     In some embodiments, the communicating hole is disposed on the limiting boss, one end of the communicating hole is in communication with the accommodating cavity, and the other end of the communicating hole is in communication with the second hole. 
     In some embodiments, the guide seat is provided with a plurality of communicating holes, and the plurality of communicating holes are disposed on the limiting boss at intervals along a circumferential direction of the guide seat. 
     By applying the technical solutions in some embodiments of the present disclosure, the electronic expansion valve includes a housing, a valve core assembly and a guide seat. The housing is provided with an accommodating cavity and a valve cavity, the valve cavity is used for communicating with a pipeline. By moving the valve core assembly between an open position and a blocking position, the valve cavity can switch between a communication state and an isolation state. In some embodiments, the guide seat is disposed between the accommodating cavity and the valve cavity, the balance channel is disposed between the guide seat and the valve seat, one end of the balance channel is in communication with the accommodating cavity, and the other end of the balance channel is in communication with the valve cavity, thereby achieving communication between the accommodating cavity and the valve cavity. When the electronic expansion valve is opened or closed, rapid pressure balance between the accommodating cavity and the valve cavity can be achieved by means of the balance channel, avoiding affecting the action performance of the valve core assembly in the expansion valve. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings of the description, constituting a part of some embodiments of the present disclosure, are used for providing further understanding to some embodiments of the present disclosure, and illustrative embodiments of the present disclosure and descriptions thereof are used for explaining some embodiments of the present disclosure, rather than constituting inappropriate limitation on some embodiments to the present disclosure. In the drawings: 
         FIG. 1  is a schematic structural diagram of an electronic expansion valve according to Embodiment 1 of the present disclosure; 
         FIG. 2  is a partially enlarged view of A in  FIG. 1 ; 
         FIG. 3  is a schematic structural diagram of a guide seat in  FIG. 1 ; 
         FIG. 4  is another schematic structural diagram of the guide seat in  FIG. 1 ; 
         FIG. 5  is a schematic structural diagram of an electronic expansion valve according to Embodiment 2 of the present disclosure; 
         FIG. 6  is a partially enlarged view of B in  FIG. 5 ; 
         FIG. 7  is a schematic structural diagram of a guide seat in  FIG. 5 ; 
         FIG. 8  is another schematic structural diagram of the electronic expansion valve according to Embodiment 2 of the present disclosure; 
         FIG. 9  is a partially enlarged view of C in  FIG. 8 ; and 
         FIG. 10  is a schematic structural diagram of the guide seat in  FIG. 8 . 
     
    
    
     Herein, the described accompanying drawings include the following reference signs: 
       10 : housing;  11 : accommodating cavity;  12 : valve cavity;  13 : sleeve;  14 : valve seat;  141 : first hole;  142 : second hole; 
       20 : valve core assembly;  21 : rotor;  22 : nut seat;  23 : screw;  24 : valve needle assembly; 
       30 : guide seat;  31 : limiting boss;  311 : first boss;  312 : second boss;  40 : balance channel;  41 : notch;  42 : communicating hole. 
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, the technical solutions in the embodiments of the present disclosure will be described clearly and thoroughly with reference to the accompanying drawings of the embodiments of the present disclosure. Obviously, the embodiments as described are only part of the embodiments of the present disclosure, and are not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit some embodiments of the present disclosure and any applications or uses thereof. On the basis of the embodiments in the present disclosure, all other embodiments obtained by a person of ordinary skill in the art without inventive effort shall all belong to the scope of protection of the present disclosure. 
     As shown in  FIGS. 1-4 , Embodiment 1 of the present disclosure provides an electronic expansion valve, the electronic expansion valve includes a housing  10 , a valve core assembly  20  and a guide seat  30 . The housing  10  is provided with an accommodating cavity  11  and a valve cavity  12 , the accommodating cavity  11  is spaced apart from the valve cavity  12 , the valve cavity  12  is used for communicating with a pipeline, the housing  10  includes a valve seat  14 , and the valve cavity  12  is disposed in the valve seat  14 . The valve core assembly  20  is movably disposed in the housing  10 , and the valve core assembly  20  has an open position and a blocking position, when the valve core assembly  20  is located in the open position, the valve cavity  12  is in a communication state, and when the valve core assembly  20  is located in the blocking position, the valve cavity  12  is in an isolation state. In this embodiment, the valve cavity  12  is connected with two pipelines; when the valve core assembly  20  is located in the open position, the two pipelines may be in communication via the valve cavity  12 ; and when the valve core assembly is located in the blocking position, the two pipelines are isolated by the valve cavity  12 . In some embodiments, the guide seat  30  is disposed in the housing  10 , and the guide seat  30  is located between the accommodating cavity  11  and the valve cavity  12 . A balance channel  40  is provided between the guide seat  30  and the valve seat  14 , one end of the balance channel  40  is in communication with the accommodating cavity  11 , and the other end of the balance channel  40  is in communication with the valve cavity  12 , thereby achieving communication between the accommodating cavity  11  and the valve cavity  12 . 
     By applying the electronic expansion valve provided in the present embodiment, the communication between the accommodating cavity  11  and the valve cavity  12  can be achieved by providing the balance channel  40  between the accommodating cavity  11  and the valve cavity  12 . When the valve core assembly  20  moves in the housing  10 , so that the valve cavity  12  is switched between the communication state and the isolation state, the accommodating cavity  11  and the valve cavity  12  achieves rapid pressure balance through the balance channel  40 , so that the valve core assembly  20  will not be damaged, avoiding affecting the action performance of the valve core assembly, and further improving the service life and reliability of the expansion valve. 
     In the present embodiment, the housing  10  further includes a sleeve  13 , the valve seat  14  is partially located in the sleeve  13 , and the valve seat  14  is fixedly connected with the sleeve  13 . A mounting hole is disposed at the end, close to the sleeve  13 , of the valve seat  14 , and the guide seat  30  is fixedly connected with the valve seat  14  through the mounting hole. In some embodiments, the mounting hole is in communication with the sleeve  13  to form the accommodating cavity  11 , the valve cavity  12  is disposed at the other end of the valve seat  14 , the valve cavity  12  is used for communicating with pipelines, a valve port is disposed in the valve cavity  12 , and the valve port is disposed at a pipe orifice of one of the pipelines. 
     In some embodiments, the mounting hole is a stepped hole. In the present embodiment, the mounting hole includes a first hole  141  and a second hole  142  which are sequentially provided and have sequentially decreasing hole diameters, and the second hole  142  is in communication with the valve cavity  12 . 
     A limiting boss  31  is disposed on an outer wall of the guide seat  30 . In the present embodiment, the limiting boss  31  is in interference fit with the first hole  141 , so as to achieve fixed connection between the guide seat  30  and the valve seat  14 , and thus a relative position between the guide seat  30  and the valve seat  14  can be limited by using the limiting boss  31 . In some embodiments, the guide seat  30  penetrates into the first hole  141  and the second hole  142 . In the present embodiment, the limiting boss  31  is in interference fit with at least one position of the first hole  141  and the second hole  142 . 
     As shown in  FIGS. 3 and 4 , the balance channel  40  includes a notch  41 , the notch  41  is disposed on a side wall of the limiting boss  31 . In some embodiments, one end of the notch  41  is in communication with the accommodating cavity  11 , and the other end of the notch  41  is in communication with the valve cavity  12 , so that the accommodating cavity  11  is in communication with the valve cavity  12  through the notch  41 . In the present embodiment, the notch  41  is of cutting surface, the cutting surface is disposed on the limiting boss  31  in a penetrating manner, and a gap exists between the cutting surface and the mounting hole to form the balance channel. In some embodiments, the extension directions of the cutting surface are the same as an axial direction of the guide seat  30 , that is, the balance channel  40  extend in a vertical direction, so as to better balance the pressure between the accommodating cavity  11  and the valve cavity  12 . 
     In some embodiments, the limiting boss  31  includes a first boss  311  and a second boss  312  which are disposed in a stepped manner, the first boss  311  is disposed corresponding to the first hole  141 , and the second boss  312  is disposed corresponding to the second hole  142 . The first boss  311  is in interference fit with the first hole  141 , and the second boss  312  is in interference fit or transition fit, clearance fit with the second hole  142 . In some embodiments, the notch  41  penetrates through the first boss  311  and the second boss  312 , so that a gap exists between the limiting boss  31  and the mounting hole, thereby forming the balance channel. 
     In the present embodiment, a plurality of notches  41  are disposed on a side wall of the guide seat  30 , and the plurality of notches  41  are disposed at intervals along a circumferential direction of the limiting boss  31 . In some embodiments, two cutting surfaces are disposed on the side wall of the guide seat  30 , the two cutting surfaces are disposed on the first boss  311  and the second boss  312  in a penetrating manner, and the cutting surface at two sides are symmetrically disposed at an interval along the circumferential direction of the limiting boss  31 . In other embodiments, the number of the notches  41  may vary depending on a use situation, and the number of the notches  41  may be three, four, and five, etc. 
     As shown in  FIGS. 5-10 , Embodiment 2 of the present disclosure provides an electronic expansion valve. Embodiment 2 differs from Embodiment 1 in that in Embodiment 2, the guide seat  30  and/or the valve seat  14  have communicating holes  42 , one end of each communicating hole  42  is in communication with the accommodating cavity  11 , the other end of the each communicating hole  42  is in communication with the valve cavity  12 , and the communicating holes  42  form the balance channel  40 . In the present embodiment, the communicating hole  42  is disposed on the guide seat  30 . In other embodiments, the communicating hole  42  may be disposed on the valve seat  14 . In some embodiments, by disposing a cutting groove on an inner wall of the valve seat, the cutting groove can be used to form the balance channel. 
     As shown in  FIG. 7 , the communicating hole  42  is disposed on the limiting boss  31 , one end of the communicating hole  42  is in communication with the accommodating cavity  11 , and the other end of the communicating hole  42  is in communication with the second hole  142 , so that the communicating hole  42  can be in communication with the valve cavity  12  through the second hole  142 . In the present embodiment, an outer diameter size of the second boss  312  is smaller than a hole diameter of the second hole  142 , so that a gap exists between the second boss  312  and the second hole  142 . In some embodiments, one end of the communicating hole  42  is in communication with the accommodating cavity  11 , and the other end of the communicating hole  42  is in communication with the valve cavity  12  through the gap between the second boss  312  and the second hole  142 . 
     As shown in  FIG. 10 , the communicating hole  42  are disposed on the inner wall of the valve seat  14 , and the communicating hole  42  is disposed in the mounting hole in a penetrating manner, so that one end of the communicating hole  42  is in communication with the accommodating cavity  11 , and the other end of the communicating hole  42  is in communication with the second hole  142 , thereby enabling the communicating hole  42  to be in communication with the valve cavity  12  through the second hole  142 . 
     In the present embodiment, the guide seat  30  has a plurality of communicating holes  42 , and the plurality of communicating holes  42  are provided on the limiting boss  31  at intervals along a circumferential direction of the guide seat  30 . In some embodiments, the guide seat  30  has two communicating holes  42 , and the two communicating holes  42  are symmetrically disposed at an interval along the circumferential direction of the guide seat  30 . In other embodiments, the number of the communicating hole  42  may vary depending on an use condition, and the number of the communicating hole  42  may be three, four, and five, etc. 
     In some embodiments, a nominal diameter of a balance channel at a single side is 0.5 to 3 mm. When the notch  41  is disposed on the side wall of the guide seat  30  provided in Embodiment 1, so that the plurality of notches form the balance channel, an area of a notch at a single side is measured and calculated, and this notch is converted into a round hole having the same area, and at this time, a diameter of the round hole is the nominal diameter of the balance channel at the single side. When the communicating holes  42  are disposed on the guide seat  30  and/or the valve seat  14  provided in Embodiment 2, so that the communicating holes  42  form the balance channel, a diameter of a communicating hole  42  at a single side is the nominal diameter of the balance channel at the single side. 
     In the present embodiment, the valve core assembly  20  includes a rotor  21 , a nut seat  22 , a screw  23 , and a valve needle assembly  24 . The rotor  21  is rotatably disposed in the accommodating cavity, and the nut seat  22  is fixedly disposed in the accommodating cavity. In some embodiments, the rotor  21  is drivingly connected with one end of the screw  23 , the valve needle assembly  24  is connected with the other end of the screw  23 , the screw  23  is disposed in the nut seat  22  in a penetrating manner, and the screw  23  is in threaded fit with the nut seat  22 . When the electronic expansion valve is opened or closed, the rotor  21  rotates in the accommodating cavity, and the rotor  21  drives the screw  23  to rotate relative to the nut seat  22 , such that the screw  23  adjusts the relative position between the valve needle assembly  24  and the valve port, thereby achieving the opening or closing of the electronic expansion valve. 
     One end of the guide seat  30  is connected with the valve seat  14 , the other end of the guide seat  30  is connected with the nut seat  22 , and an outer circumference of the guide seat  30  is in transition fit or interference fit with an inner hole of the nut seat  22 , thereby guiding the nut seat  22 , and improving a coaxiality of the nut seat  22  and the valve seat  14 . In some embodiments, the guide seat  30  has a connecting segment and a limiting segment that are disposed opposite to each other, and the limiting boss  31  is disposed on the limiting segment. The connecting segment is inserted into the nut seat  22  in an interference fit manner, so as to achieve fixed connection between the guide seat  30  and the nut seat  22 . In some embodiments, the guide seat  30  has a guide hole, the guide hole is disposed in the connecting segment, an extension direction of the guide hole is the same as the axial direction of the guide seat  30 , and the valve needle assembly  24  is movably disposed in the guide hole. By means of the described structure, the guide seat  30  is disposed between the nut seat  22  and the valve seat  14 , and the guide seat  30  can be used to guide the valve needle assembly  24 , thereby ensuring a coaxiality between the nut seat  22 , the valve needle assembly  24  and the valve seat  14 . 
     The valve needle assembly  24  includes a valve needle and a pretightening spring. A first end of the valve needle is disposed towards the valve port, a second end of the valve needle is connected with the screw  23 , the pretightening spring is disposed between the valve needle and the screw  23 , and the pretightening spring is used for providing a pretightening force to the valve needle. In some embodiments, when the valve needle abuts against the valve port, the pretightening spring can reduce an impact force between the valve needle and the valve port, and the valve port can be opened under a certain pressure difference when flowing reversely, thereby protecting the valve needle, the valve port and a system. 
     The notch  41  is disposed on the side wall of the guide seat  30 , or the communicating holes  42  are disposed on the guide seat  30  and/or the valve seat  14 , so that balance channel  40  is disposed between the accommodating cavity  11  and the valve cavity  12 . When the electronic expansion valve is opened or closed, rapid pressure balance between the accommodating cavity  11  and the valve cavity  12  can be achieved by means of the balance channel  40 , so that components inside the housing  10  are not damaged, further prolonging the service life of the expansion valve. 
     The content above only relates to some embodiments of the present disclosure, and is not intended to limit some embodiments of the present disclosure. For a person skilled in the art, some embodiments of the present disclosure can have various modifications and changes. Any modifications, equivalent replacements, improvements and the like made within the principle of the present disclosure shall fall within the scope of protection of the present disclosure.