The present application relates to the technical field of refrigerant fluid control components, and particularly to a thermal expansion valve. Moreover, the present application further relates to a refrigerating system including the thermal expansion valve.
A thermal expansion valve is one of the important components composing a refrigerating system, and is one of the four essential components with the other three including an evaporator, a compressor, and a condenser in a refrigerating system. The thermal expansion valve mainly functions to control the size of opening of the valve by sensing the degree of superheating at the outlet end of the evaporator or the intake end of the compressor in the refrigerating system so as to regulate the flow of the refrigerant in the system, throttle and reduce the pressure.
Referring to
The thermal expansion valve includes a valve body V. The upper end of the valve body 1′ is connected with an air box including an air box base 2′4 and an air box cover 2′5. The inner chamber of the air box is partitioned into an upper chamber 2′2 and a lower chamber 2′3 by a diaphragm 2′1. As shown in
Furthermore, as shown in
Taking the valve core 3′1 and the transmission rod 3′2 as objects for force analysis, the valve core 3′1 and the transmission rod 3′2 are subjected to both an upward elastic force Pt and a downward pushing force applied by the transmission piece 3′3. The diaphragm 2′1 pushes the transmission piece 3′3 so as to generate this pushing force, so the pushing force is just the force driving the diaphragm 2′1 to move downwards, i.e., Pb−Po. When the valve core 3′1 is in a balanced state, Pb−Po=Pt, i.e., Pb=Po+Pt. When the temperature at the outlet end of the evaporator is too high, the Pb increases, so that the valve core 3′1 is pushed to move downwards, thereby increasing the flow of the refrigerant. When the temperature at the outlet end of the evaporator is too low, the Pb decreases, so that the valve core 3′1 is pushed to move upwards, thereby decreasing the flow of the refrigerant.
However, as shown in
In view of this, as shown in
Though the thermal expansion valve shown in
It is to be noted that, when the transmission piece 3′3 and the transmission rod 3′2 are connected in a completely sealed manner without any clearance therebetween, taking the transmission piece 3′3, the transmission rod 3′2 and the valve core 3′1 as a whole as an object for force analysis, the top surface of the transmission piece 3′3 may be still subjected to a downward force generated from the pressure of the refrigerant in the lower chamber 2′3, and the area subjected to this applied force is just the sealing area between the transmission rod 3′2 and the transmission piece 3′3, i.e., the area of the upper end surface of the transmission rod 3′2. Therefore, the valve core 3′1 may be still subjected to an applied downward force. Due to the resulting force, the systematic pressure difference cannot be absolutely zero, and therefore, the accuracy of the regulation of the valve core 3′1 may yet be influenced.
Furthermore, the following deficiencies still exist in the thermal expansion valve shown in
First, the transmission rod 3′2, the valve core 3′1 and the guide ball 3′4 are provided separately. Thus, the number of the parts is huge, resulting in a relatively big accumulated dimension tolerance in the axial direction, a reduced accuracy of the regulation and a reduced performance of the thermal expansion valve, and a cumbersome assembly.
Second, the balance chamber 1′4 communicates with the first interface chamber 1′2, and when the first interface chamber 1′2 is a high pressure end, pressure in the balance chamber 1′4 is high, which imposes high requirement on the sealing and increases the risk of leakage.
Third, providing the through hole 3′11 in the relatively small valve core 3′1 causes a difficult processing.
One technical problem to be solved by the present application is to provide a thermal expansion valve, which is structured to reduce the systematic pressure difference applied to the valve core component, so that the accuracy of the regulation of the valve core component may be improved. Furthermore, another technical problem to be solved by the present application is to provide a refrigerating system including the thermal expansion valve.
To solve the above technical problem, the present application provides a thermal expansion valve, including a valve body. An air box is provided at the upper end of the valve body. The inner chamber of the air box is partitioned into an upper chamber and a lower camber by a diaphragm. A valve core component and a valve port fitted with the valve core component are provided in the inner chamber of the valve body. The lower end portion of the valve body is further provided with a balance chamber configured to balance the valve core component. The upper end portion of the valve core component is arranged in the lower chamber, and the lower end portion of the valve core component is arranged in the balance chamber of the valve body. The balance chamber communicates with the lower chamber, and is sealed to be isolated from the inner chamber of the valve body.
Preferably, a projected area of an upper pressure-bearing surface, subjected to pressure in the lower chamber, of the upper end portion of the valve core component on a plane perpendicular to an axis of the valve core component is substantially equal to a projected area of a lower pressure-bearing surface, subjected to pressure in the balance chamber, of the lower end portion of the valve core component on a plane perpendicular to the axis of the valve core component.
Preferably, when the valve core component and the valve port are closed, a sealing line or a sealing surface between the valve port and the valve core component partitions the inner chamber of the valve body into a first interface chamber and a second interface chamber. A first pressure-bearing surface and a second pressure-bearing surface subjected to opposite forces are provided on the side wall of the valve core component in the first interface chamber.
Preferably, the projected area of the first pressure-bearing surface on the plane perpendicular to the axis of the valve core component is substantially equal to the projected area of the second pressure-bearing surface on the plane perpendicular to the axis of the valve core component.
Preferably, a third pressure-bearing surface and a fourth pressure-bearing surface subjected to opposite forces are provided on the side wall of the valve core component in the second interface chamber.
Preferably, the projected area of the third pressure-bearing surface on the plane perpendicular to the axis of the valve core component is substantially equal to the projected area of the fourth pressure-bearing surface on the plane perpendicular to the axis of the valve core component.
Preferably, the valve core component is provided with an inclined sealing surface for sealing the valve port. When the valve core component and the valve port are closed, a sealing line between the valve core component and the valve port partitions the inclined sealing surface into the second pressure-bearing surface in the first interface chamber and the third pressure-bearing surface in the second interface chamber.
Preferably, the balance chamber communicates with the outlet end of the evaporator.
Preferably, the valve body is provided therein with a communicating hole communicating with the lower chamber. The communicating hole communicates with the balance chamber via first capillary arranged outside the valve body.
Preferably, the side wall of the valve body is provided with a first mounting hole communicating with the communicating hole, and a second mounting hole communicating with the balance chamber. One end of the first capillary is arranged in the first mounting hole, and the other end of the first capillary is arranged in the second mounting hole.
Preferably, the air box includes an air box base connected to the valve body. Each of the first mounting hole and the second mounting hole is arranged obliquely such as to have a downward inner end and an upward outer end, no matter whether the air box base is positioned upwards or downwards.
Preferably, the angle between the axis of the first mounting hole and the axis of the valve body is equal to the angle between the axis of the second mounting hole and the axis of the valve body.
Preferably, the air box includes an air box base connected to the valve body. No matter whether the air box base is positioned upwards or downwards, the side wall of the valve body is provided thereon with an inclined surface having an inward upper end and an outward lower end, so that the first capillary rests against the inclined surface.
Preferably, a capillary groove is provided in the side wall of the valve body, and the first capillary is arranged in the capillary groove.
Preferably, a connecting hole is integrally formed and communicates with the communicating hole and is located below the communicating hole. The connecting hole directly communicates with the balance chamber.
Preferably, the upper pressure-bearing surface of the valve core component is connected to a transmission piece with a clearance between the upper pressure-bearing surface and the transmission piece. The valve core component is provided with a valve core component through hole in an axial direction, and the lower chamber communicates with the balance chamber via the valve core component through hole.
Preferably, the upper end portion of the valve body is provided with an annular chamber, and an elastic component is provided in the annular chamber. The bottom end of the elastic component is supported on the bottom wall of the annular chamber or on a first spring seat, and the top end of the elastic component supports a transmission piece connected to the valve core component.
Preferably, the annular chamber further communicates with the balance chamber via the first capillary.
Preferably, a guide component is provided outside of the valve core component and is arranged in the inner chamber of the lower end portion of the valve body. The balance chamber is sealed to be isolated from the second interface chamber by means of the guide component and the sealing member arranged on the guide component. The opening in the lower portion of the balance chamber is threadingly connected with a valve bonnet configured to support the guide component.
Preferably, a clamping depression for being clamped by a clamping tool is provided on an external portion of the lower end portion of the valve core component in the balance chamber.
Furthermore, to solve the above technical problems, the present application further provides a refrigerating system, including an evaporator. The heat exchange device further includes any thermal expansion valve described above. The upper chamber is connected to the outlet end of the evaporator via a temperature sensing component, and the lower chamber communicates with the outlet end of the evaporator via a balance tube.
Based on the above prior art, the thermal expansion valve of the present application is improved in that the lower chamber of the air box communicates with the balance chamber which is sealed to be isolated from the inner chambers of the valve body. Since the lower chamber communicates with the balance chamber, the pressures in the lower chamber and in the balance chamber are equal to each other. Thus, when the projected area of the upper pressure-bearing surface of the valve core component on the plane perpendicular to the axis of the valve core component is equal to the projected area of the lower pressure-bearing surface of the valve core component on the plane perpendicular to the axis of the valve core component, the force applied to the valve core component by the refrigerant in the lower chamber and the force applied to the valve core component by the refrigerant in the balance chamber are equal but opposite to each other and thus counteract each other, so that the systematic pressure difference applied to the valve core component is reduced effectively. It is to be noted that, even when the projected area of the upper pressure-bearing surface of the valve core component on the plane perpendicular to the axis of the valve core component is not equal to the projected area of the lower pressure-bearing surface of the valve core component on the plane perpendicular to the axis of the valve core component, since the pressures in the two chambers are equal to each other, the structural design may reduce the systematic pressure difference applied to the valve core component as compared with the prior art.
In summary, the thermal expansion valve according to the present application is capable of reducing the systematic pressure difference applied to the valve core component, so that the accuracy of the regulation of the valve core component is improved.
Furthermore, the refrigerating system including the above thermal expansion valve according to the present application has the same technical effects as those of the above thermal expansion valve, which is therefore omitted for simplicity.
Specifically, the correspondence between reference numerals in
Specifically, the correspondence between the reference numerals in
An aspect of the present application is to provide a thermal expansion valve, which has a structural design capable of reducing the systematic pressure difference across the valve core component, so as to improve the accuracy of the regulation of the valve core component. Furthermore, another aspect of the present application is to provide a refrigerating system including the thermal expansion valve.
For those skilled in the art to understand better the technical solutions of the present application, the present application will be further explained in detail in conjunction with the accompanying drawings and the specific embodiments.
It is to be noted that all of the term “above, under, left and right” as used herein take the location shown in the accompanying drawings for reference, and therefore cannot be construed as limiting the scope of protection of the present application.
Referring to
In the fundamental technical solution of the present application, as shown in
Furthermore, as shown in
Taking the valve core component 3 as an object for force analysis, the valve core component 3 is subjected to both an upward elastic pressure Pt, and a downward pushing force applied by the transmission piece 32. The diaphragm 21 pushes the transmission piece 32 to form the pushing force, and the pushing force therefore is just the force driving the diaphragm 21 to move downwards, i.e., Pb−Po. When the valve core component 3 is in a balanced state, Pb−Po=Pt, i.e., Pb=Po+Pt. When the temperature of the outlet end of the evaporator is too high, the Pb increases, so that the valve core component 3 is pushed to move downwards, thereby increasing the flow of the refrigerant. When the temperature of the outlet end of the evaporator is too low, the Pb decreases, so that the valve core component 3 is pushed to move upwards, thereby decreasing the flow of the refrigerant.
Based on the above prior art, the thermal expansion valve of the present application is improved in that the lower chamber 23 of the air box communicates with the balance chamber 14 which is sealed to be isolated from both the first interface chamber 12 and the second interface chamber 13. Since the lower chamber 23 communicates with the balance chamber 14, the pressures in the lower chamber 23 and in the balance chamber 14 are equal to each other. Thus, as shown in
It is to be noted that, first, in the present fundamental technical solution, the present application focuses on whether the lower chamber 23 communicates with the balance chamber 14 or not, rather than by which structure the lower chamber 23 communicates with the balance chamber 14, and therefore, any structural design, so long as it enables the lower chamber 23 to communicate with the balance chamber 14, should fall into the scope of protection of the present application; second, in the fundamental technical solution, the structure of the valve core component 3 is not limited in the present application, for example, the valve core component 3 may be of a structure having separated parts (i.e., including the valve core 3′1 and the transmission rod 3′2) in the prior art as described above, or may be an integrated part in
The above fundamental technical solution may further be improved. For example, referring to
In the prior art as shown in
However, in the present application, each of the first pressure-bearing surface S1 and the second pressure-bearing surface S2 is provided in the first interface chamber 12, so there is no necessary to provide a through hole in the valve core component 3, and further no necessary to provide a guide ball and a transmission rod. Thus, the valve core component 3 may adopt an integrated structure with only one part, so as to ensure the axial dimension tolerance and improve the accuracy of the regulation. Second, since there is no necessary to provide a through hole in the valve core component 3, so that the balance chamber 14 does not communicate with the first interface chamber 12, when the first interface chamber 12 is a high pressure end, the pressure in the balance chamber 14 is relatively low, which has low sealing requirement and thus reduces the risk of leakage. Third, the processing of providing a through hole in the valve core component 3 is omitted, so that the processing becomes easy and the processing cost is reduced.
The above fundamental technical solution may further be improved. For example, as shown in
Specifically, in the above fundamental technical solution, when the valve core component 3 is closed, if the refrigerant flows from the first interface chamber 12 to the second interface chamber 13, the pressures applied to the first pressure-bearing surface S1 and the second pressure-bearing surface S2 are equal but opposite to each other, and the third pressure-bearing surface S3 and the fourth pressure-bearing surface S4 are not subjected to the pressures from the refrigerant. Also, the upper pressure-bearing surface S5 and the lower pressure-bearing surface S6 of the valve core component 3 are not subjected to the pressures from the refrigerant as well. Further, since the force area of the first pressure-bearing surface S1 is equal to the force area of the second pressure-bearing surface S2, the pressures applied to the valve core component 3 by the refrigerant in the system are balanced, and thus the valve core component 3 is not affected by the fluctuation of the pressure of the refrigerant in the system. Similarly, when the valve core component 3 is closed, if the refrigerant flows from the second interface chamber 13 to the first interface chamber 12, with the analysis process substantially opposite to the above process, the pressures applied to the valve core component 3 by the refrigerant in the system are balanced, and thus the valve core component 3 is not affected by the fluctuation of the pressure of the refrigerant in the system.
After the valve core component 3 is opened, if the refrigerant flows from the first interface chamber 12 to the second interface chamber 13, pressures from high-pressure fluid are applied to the first pressure-bearing surface 51 and the second pressure-bearing surface S2 in opposite directions; pressures from low pressure fluid after being throttled are applied to the third pressure-bearing surface S3 and the fourth pressure-bearing surface S4 in opposite directions; and pressures from fluid at the outlet end of the evaporator are applied to the upper pressure-bearing surface S5 and the lower pressure-bearing surface S6 of the valve core component 3 in opposite directions. Since the force area of the first pressure-bearing surface S1 is equal to the force area of the second pressure-bearing surface S2, and the force area of the third pressure-bearing surface S3 is equal to the force area of the fourth pressure-bearing surface S4, and the force area of the upper pressure-bearing surface S5 of the valve core component 3 is equal to the force area of the lower pressure-bearing surface S6 of the valve core component 3, the pressures applied to the valve core component 3 by the refrigerant in the system are balanced, and thus the valve core component 3 is not affected by the fluctuation of the pressure of the refrigerant in the system. Similarly, when the valve core component 3 is opened, if the refrigerant flows from the second interface chamber 13 to the first interface chamber 12, with the analysis process substantially opposite to the above process, the pressures applied to the valve core component 3 by the refrigerant in the system are balanced, and thus the valve core component 3 is not affected by the fluctuation of the pressure of the refrigerant in the system.
In summary, the thermal expansion valve according to the present application may achieve a balanced flowing in double directions, and the balance in the present application is a perfect balance which is different from only a rough balance in the prior art.
In the above fundamental technical solution, a structure for communicating the lower chamber 23 with the balance chamber 14 may be specifically configured. Specifically, referring to
As shown in
Specifically, as shown in
Furthermore, based on the communicating hole 15, another communicating structure may further be adopted. For example, as shown in
Further improvement may be made based on the above communicating structure. Referring to
Specifically, the side wall of the valve body 1 is provided with a first mounting hole 17 communicating with the connecting hole 151, and a second mounting hole 18 communicating with the balance chamber 14. One end of the first capillary 41 is arranged in the first mounting hole 17, with the other end thereof being arranged in the second mounting hole 18.
Further, as shown in
Furthermore, as shown in
Further, as shown in
Referring to
In this embodiment, the upper pressure-bearing surface S5 of the valve core component 3 is connected to the transmission piece 32 with a clearance therebetween. Based on this, the valve core component 3 is provided with a valve core component through hole 33 in an axial direction so that the lower chamber 23 communicates with the balance chamber 14 via the valve core component through hole 33. Apparently, such a structure may be used to communicate the lower chamber 23 and the balance chamber 14 as well.
Referring to
Further improvements may be made as well based on any of the above technical solutions. For example, the elastic component 6 may be arranged at the upper end portion of the valve body 1. Specifically, as shown in
Further, in the above embodiments, the annular chamber 5 further communicates with the balance chamber 14 via the first capillary 41, so that the lower chamber 23 and the balance chamber 14 communicates with each other. The structural design of the connecting hole 151 is omitted in such a structure, thereby simplifying the communicating structure.
Furthermore, as shown in
As shown in
Furthermore, as shown in
Referring to
This embodiment is substantially similar to the technical solutions shown in
However, in the technical solution shown in
Referring to
In this embodiment, as shown in
It is to be noted that, in any one of the above embodiments, the upper pressure-bearing surface S5 is a cross section of the valve core component 3 perpendicular to the axis of the valve core component 3 at the position where the sealing member 35 is located, and the lower pressure-bearing surface S6 is a cross section of the valve core component 3 perpendicular to the axis of the valve core component 3 at the position where the sealing member 71 is located. As shown in
Furthermore, it is to be noted that, as shown in
Furthermore, the present application further provides a refrigerating system, including a compressor, a thermal expansion valve, an evaporator and a condenser. The thermal expansion valve is the one in any of the embodiments described above. An upper chamber 22 is connected to the outlet end of the evaporator via a temperature sensing component, and a lower chamber 23 communicates with the outlet end of the evaporator via a balance tube. Specifically, the refrigerating system may be a thermal pump or an air conditioner. The other portions of the refrigerating system may refer to the prior art, which will not be described herein.
The refrigerating system and the thermal expansion valve thereof according to the present invention are described above in detail. In the description, specific examples are used to illustrate the principle and implementation of the present invention. The description of the embodiments is used only to help better understanding the method and concept of the present invention. It should be noted that, various improvements and modifications can be made to the invention by those skilled in the art without departing from the principle of the present invention, and these improvements and modifications also fall within the scope of protection defined by the claims.
Number | Date | Country | Kind |
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201110007936.3 | Jan 2011 | CN | national |
The present application is the US national phase of International Application No. PCT/CN2012/070276, filed on Jan. 12, 2012, which claims the priority from Chinese Patent Application No. 201110007936.3 titled “REFRIGERATING SYSTEM AND THERMAL EXPANSION VALVE THEREOF” and filed with the State Intellectual Property Office on Jan. 14, 2011, the entire disclosure of which is incorporated herein by reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CN12/70276 | 1/12/2012 | WO | 00 | 7/12/2013 |