Active balance valve adapted to be actuated by stepper motor and adapted for refrigeration and / or air conditioning applications

Abstract

The invention relates to a stepper motor actuated active balance valve for refrigeration and / or air conditioning applications. The valve includes a valve housing having an inlet orifice, an outlet orifice, and a mounting portion, a main valve element having a main pressure balancing orifice, and a control element at least partially defining a pressure balancing passage. Each element is slidable within the valve housing and includes a control surface for controlling fluid flow between the inlet orifice and the outlet orifice and / or pressure propagation between the outlet orifice and an interior of the main valve element. The control element closes the primary pressure balancing orifice of the primary valve element in a closed state of the valve.

Description

[0001] The present invention relates to a stepper motor actuated active balancing valve for refrigeration and / or air conditioning applications. The valve comprises a valve housing having an inlet orifice, an outlet orifice and a mounting portion, a main valve element having a main pressure balancing orifice, and a control element actuated by a stepper motor and at least partially defining a pressure balancing channel. Each element is slidable within the valve housing and comprises a control surface for controlling fluid flow between the inlet orifice and the outlet orifice and / or pressure propagation between the outlet orifice and the interior of the main valve element. The control element closes the main pressure balancing orifice of the main valve element in the closed state of the valve.

[0002] Balancing valves known from the prior art are typically used as expansion valves of medium to large capacities. Here, a control element in the form of a cone or a piston is provided to control the aperture of the valve. Due to the pressure difference between the inlet and the outlet of the valve, a considerable resultant force may act on the control element, thereby deteriorating the movement of the control element and thus the function of the valve. In order to reduce the forces acting on the control element, the pressures acting on the control element are balanced. Thus, the pressure balancing reduces or eliminates the forces required to operate the control element under high pressure differences.

[0003] However, a problem with known balancing valves is that balancing the control element in the manner described introduces a secondary leakage path. In order to avoid excessive leakage in the closed position of the valve, a secondary seal is typically introduced. This is usually a dynamic seal, located between the control element and the valve housing, causing friction when the control element moves up and down. In some cases, the friction from this seal may be the main force required by the actuator to move the control element. Therefore, the seal increases the overall force requirement, thereby increasing the size and cost of the overall solution. In addition, friction may introduce opening and control hysteresis, thereby limiting the control accuracy of the valve.

[0004] The object of the present invention is to provide an improved balancing valve which overcomes the above-mentioned problems. This object is achieved by an active balancing valve comprising the features of claim 1. Advantageous embodiments of the invention are the subject matter of the dependent claims.

[0005] According to the present invention, a stepper motor actuated active balancing valve for refrigeration and / or air conditioning applications is provided. The active balancing valve comprises a valve housing having an inlet orifice, an outlet orifice and a mounting portion, a main valve element having a main pressure balancing orifice, and a control element actuated by a stepper motor and at least partially defining a pressure balancing channel. Each element can slide in the valve housing and include a control surface for controlling the fluid flow between the inlet orifice and the outlet orifice and / or the pressure propagation between the outlet orifice and the interior of the main valve element. In the context of the present invention, the term "control surface" refers to a part of a component that is or can be in direct contact with a fluid to control the amount of corresponding fluid flow and / or pressure propagation. Fluid flow and / or pressure propagation can be controlled by spacing the control surface relative to another surface or by contacting the control surface with the other surface. The space or lack of space between the control surface and the other surface controls fluid flow and pressure propagation. The stepper motor can be considered as the main actuator for actuating the valve.

[0006] The main valve element comprises a primary control surface which may be spaced apart from or in contact with the valve seat for controlling the fluid flow between the inlet orifice and the outlet orifice. The control element comprises a secondary control surface which may be spaced apart from or in contact with the main pressure balancing orifice for controlling the pressure propagation between the inlet orifice, the outlet orifice and the fluid chamber. Contacting the main pressure balancing orifice may be understood as contacting the edge of the main pressure balancing orifice and thus closing the main pressure balancing orifice by the secondary control surface. The control element closes the main pressure balancing orifice of the main valve element in the closed state of the valve.

[0007] The valve according to the invention makes it possible to use a secondary seal which provides sealing only in the closed valve position. Furthermore, balancing of the valve only takes place when the valve should be open. Thus, an actively balanced valve is provided which removes the friction contribution of the secondary seal, resulting in a significant reduction in the actuator force requirement. At the same time, control hysteresis is eliminated.

[0008] In a preferred embodiment of the invention, the control element is at least partially arranged inside the main valve element. The two elements can be cylindrical in form, so that the control element can slide at least partially into the main valve element through the cylindrical surface of the main valve element. The cylindrical form described can be understood in a broad sense and can refer to a partially cylindrical or cylindrical shape.

[0009] In another preferred embodiment of the present invention, the control element can slide relative to the main valve element, wherein preferably, the sliding distance corresponds to the distance between the position where the secondary control surface of the control element contacts the main pressure balance orifice and the position where the secondary stop portion of the control element contacts the main stop portion of the main valve element.

[0010] In another preferred embodiment of the present invention, the secondary stop and the primary stop can contact to block the passage of fluid from the inlet orifice to the outlet orifice. By providing such a perfect or near-perfect fluid barrier, up to 100% perfect or near-perfect pressure balance can be achieved. In addition, the stop can combine two functions at the same part of the valve: blocking the passage of fluid from the inlet orifice to the outlet orifice and limiting the relative movement of the two related parts. This combination of two functions simplifies the manufacture of the valve, so that the tolerance requirements can be simplified.

[0011] In another preferred embodiment of the present invention, the secondary pressure balancing orifice is arranged in the control element, between the secondary control surface of the control element and the secondary stop. The arrangement of the secondary pressure balancing orifice between the secondary control surface and the secondary stop ensures that a pressure balancing path through the control element can be provided, even in a state where the stop of the control element and the stop of the main valve element are engaged to block the fluid passage from the inlet orifice to the outlet orifice.

[0012] In another preferred embodiment of the invention, the main valve element comprises two main valve element parts, wherein the inner main valve element part is insertable into the outer main valve element part and comprises the main stop. The two different parts of the main valve element facilitate its manufacture and provide a varying inner diameter of the main valve element, which serves as a stop, as a control surface and / or as a guide surface.

[0013] In another preferred embodiment of the present invention, the two main valve element parts include a fluid conduit for connecting the inlet orifice fluid to the interior of the inner main valve element part. The fluid conduit of the main valve element part can be arranged at a position corresponding to the middle diameter portion of the control element so as to facilitate the fluid flow between the inlet orifice and the outlet orifice.

[0014] In another preferred embodiment of the present invention, the stepper motor or a part of the stepper motor is provided at the mounting portion.

[0015] In another preferred embodiment of the present invention, a fluid chamber is arranged between the stepper motor on one side and the control element and the main valve element on the other side, the fluid chamber being fluidically connected to the pressure balancing channel. The positioning and geometry of the fluid chamber ensure that the pressure of the fluid inside the chamber can act on one side of the main valve element and / or the control element to balance the pressure acting on the other side of the main valve element. In particular, the area over which the pressure inside the fluid chamber acts in the axial direction towards the main valve element and / or the control element can be equal to the area exposed to the pressure acting on the main valve element and / or the control element at the outlet orifice of the valve.

[0016] In another preferred embodiment of the invention, a spring is provided for pressing the control element and / or the main valve element in the direction of the outlet opening. The spring can ensure that the valve remains closed in a default state in which the actuator does not apply a force to the main valve element.

[0017] In another preferred embodiment of the present invention, the control element includes a check valve and / or the main valve element includes a seal toward the valve housing. The check valve can ensure that the fluid chamber is connected to the inlet orifice and / or the outlet orifice only when the pressure at both ends of the check valve exceeds a certain threshold. Alternatively or additionally, the check valve can ensure that pressure balancing can be performed under reverse flow conditions, in which the fluid pressure is higher at the outlet orifice than at the inlet orifice. Under these conditions, the check valve can ensure that the valve is pressure-balanced by opening a fluid path between the high-pressure outlet orifice and the fluid chamber, so that the high pressure acting on the control element and / or the main valve element at the outlet orifice is balanced by the same high pressure acting on the control element and / or the main valve element at the fluid chamber.

[0018] In another preferred embodiment of the present invention, the control element is slidable relative to the main valve element and / or the control element comprises a large diameter cylindrical portion and a small diameter cylindrical portion, wherein the large diameter cylindrical portion extends over a greater distance in the axial direction of the valve than the small diameter cylindrical portion.

[0019] In another preferred embodiment of the present invention, the secondary pressure balance orifice is arranged at the small diameter cylindrical or conical part or between the large diameter cylindrical part and the small diameter cylindrical or conical part, and / or the pressure balance channel is connected to the secondary pressure balance orifice. The conical part can be arranged between the large diameter cylindrical part and the small diameter cylindrical or conical part. The secondary pressure balance orifice can be aligned perpendicular to the pressure balance channel.

[0020] In another preferred embodiment of the present invention, the control element can slide relative to the main valve element and / or the control element includes a large diameter cylindrical part, a small diameter cylindrical part, a medium diameter cylindrical part, and a short large diameter cylindrical part, wherein the large diameter cylindrical part extends over a greater distance in the axial direction of the valve than the small diameter cylindrical or conical part, and / or wherein the medium diameter cylindrical part is located between the large diameter cylindrical part and the short large diameter cylindrical part.

[0021] In another preferred embodiment of the present invention, another secondary pressure balancing orifice is provided at the short large-diameter cylindrical portion, and preferably, the pressure balancing passage is connected to the another secondary pressure balancing orifice.

[0022] In another preferred embodiment of the present invention, the large-diameter cylindrical portion and the short large-diameter cylindrical portion have the same diameter.

[0023] In another preferred embodiment of the present invention, the interior of the main valve element comprises an inner small diameter cylindrical portion and an inner large diameter cylindrical portion, wherein the inner small diameter cylindrical portion is longer than the inner large diameter cylindrical portion in the axial direction of the main valve element.

[0024] In another preferred embodiment of the present invention, a secondary stop of the control element is arranged opposite to the small diameter cylindrical or conical portion for contacting a primary stop of the main valve element, and / or a fluid conduit is arranged for connecting the inlet orifice fluid to the interior of the main valve element.

[0025] In another preferred embodiment of the present invention, the distance between the inner small diameter cylindrical portion and the short large diameter cylindrical portion at least partially defines a fluid passage from the inlet orifice to the outlet orifice.

[0026] Further details and advantages of the invention are disclosed in the claims and in the following description of embodiments shown in the accompanying drawings. The drawings show:

[0027] Figure 1 : A cross-sectional view of a first embodiment of the present invention;

[0028] Figure 2 : An enlarged cross-sectional view of a first embodiment of the present invention;

[0029] Figures 3a to 3d : A cross-sectional view of the first embodiment of the present invention at various valve positions;

[0030] Figure 4 : An enlarged cross-sectional view of a second embodiment of the present invention;

[0031] Figure 5a to Figure 5c : A cross-sectional view of the second embodiment of the present invention at various valve positions;

[0032] Figure 6 : An enlarged cross-sectional view of a third embodiment of the present invention;

[0033] Figures 7a to 7d : A cross-sectional view of a third embodiment of the present invention at various valve positions;

[0034] Figure 8 : A cross-sectional view of a fourth embodiment of the present invention;

[0035] Figures 9a to 9c : A cross-sectional view of a fourth embodiment of the present invention at various valve positions;

[0036] Fig.10 : Flow curves describing the flow characteristics of various embodiments;

[0037] Fig.11: A system diagram showing possible applications of the valve according to the invention;

[0038] Fig.12 : A cross-sectional view of a fifth embodiment of the present invention;

[0039] Figures 13a to 13c : A cross-sectional view of a fifth embodiment of the present invention at various valve positions; and

[0040] Figures 14a to 14c : Cross-sectional views of the sixth embodiment of the present invention at various valve positions.

[0041] Figure 1 A cross-sectional view of a first embodiment of an active balancing valve according to the present invention is shown. The valve comprises a valve housing 1 having an inlet orifice 11, an outlet orifice 12 and a mounting portion 13. The inlet orifice 11 and the outlet orifice 12 can provide a fluid connection between the inside and the outside of the valve, so that the fluid can flow between the orifices 11, 12 in the open state of the valve. The valve can be configured to allow the fluid to flow in any direction between the two orifices 11, 12. The term orifice can be understood broadly and can include a plurality of orifices. For example, the inlet orifice 11 comprises two or more separate orifices, which can be arranged in a circumferential direction around the central axis of the valve. The inlet orifice 11 can be oriented perpendicular to the outlet orifice 12. The mounting portion 13 can include a circular opening for inserting a component of the valve and / or some mounting geometry for mounting an actuator (such as a stepper motor 4). The valve can include a complete stepper motor 4 or a portion of a stepper motor 4 for actuating a control element 2.

[0042] A fluid chamber 5 and / or a spring 7 may be provided between the stepper motor 4 and the housing 1. The spring 7 and / or the fluid in the fluid chamber 5 may exert a force on other components of the valve.

[0043] Figure 2 yes Figure 1 1. An enlarged cross-sectional view of a first embodiment of the present invention is shown. Throughout the description and drawings, for the sake of clarity, the same reference numerals are used for the same features. Here, the components that can be inserted into the valve housing 1 are shown enlarged and include a main valve element 3 with a main pressure balance orifice 31, and a control element 2. The control element 2 is at least partially arranged inside the main valve element 3. The upper part of the control element 2 can be retained outside the main valve element 3 to facilitate the connection of the control element to the stepper motor 4.

[0044] The main pressure balancing orifice 31 of the main valve element 3 is shown as being closed by the control element 2 in the closed state of the valve. Inserting the secondary control surface 22 of the control element 2 into the main pressure balancing orifice 31 limits the fluid connection between the outlet orifice 12 and the fluid chamber 5 and thus at least partially defines the pressure balancing passage 21 between the outlet orifice 12 and the fluid chamber 5. In other words, the position of the control element 2 inside the main valve element 3 changes the extent to which pressure can propagate between the fluid chamber 5 and the orifices 11, 12, with the result that pressure balancing of the control element 2 and / or the main valve element 3 is provided.

[0045] The pressure balance channel 21 can be understood as Figure 1 A partial or complete fluid passage between the fluid chamber 5 and the main pressure balance orifice 31 is shown.

[0046] The control element 2 and the main valve element 3 may be slidably arranged inside the valve housing 1. Each of these elements 2, 3 may include at least one control surface 22, 32 for controlling the fluid flow between the inlet orifice 11 and the outlet orifice 12 and / or the pressure propagation between the outlet orifice 12 and the interior of the main valve element 3.

[0047] The control element 2 is slidable relative to the main valve element 3. The sliding distance may correspond to the distance between the position where the secondary control surface 22 of the control element 2 contacts the main pressure balance orifice 31 and the position where the secondary stop 23 of the control element 2 contacts the main stop 33 of the main valve element 3. The secondary stop 23 of the control element 2 may include an at least partially circular edge that may abut a corresponding portion of the main stop 33 of the main valve element 3.

[0048] The secondary stop 23 and the main stop 33 may contact to block the fluid passage from the inlet orifice 11 to the outlet orifice 12. In this case, the two stops 23, 33 may include contact planes arranged respectively in the circumferential direction of the control element 2 and the main valve element 3. When the contact planes approach and eventually contact each other, the gap between these planes is minimized so that eventually no fluid flow or only negligible fluid flow can pass through the stops 23, 33 when in contact.

[0049] The pressure can then propagate from the outlet orifice 12 to the fluid chamber 5 via a secondary pressure balancing orifice 24 which is arranged in the control element 2 between the secondary control surface 22 and the secondary stop 23 of the control element 2. Figure 2 In the case shown, the outlet orifice 12 is fluidically closed by closing the control surface 22 of the main pressure-balancing orifice 31 and the main control surface 32 of the closing valve seat 14 .

[0050] The main valve element 3 may comprise two main valve element parts 34, 35. Here, the inner main valve element part 35 is insertable into the outer main valve element part 34. The inner main valve element part 35 comprises a main stop 33. Both main valve element parts comprise fluid conduits 36, 37 for fluidly connecting the inlet orifice 11 to the interior of the inner main valve element part 35. The inner main valve element part 35 may comprise at least one inner fluid conduit 37, and the outer main valve element part 34 may comprise at least one outer fluid conduit 36. Between the fluid conduits 36, 37, a circumferential gap may be provided to facilitate the fluid connection between said fluid conduits 36, 37.

[0051] Figures 3a to 3d A cross-sectional view of a first embodiment of the present invention is shown at various valve locations. Figure 3a The valve is shown in a fully closed position. Here, the stepper motor 4 has pushed the control element 2 to its lowest position, effectively pushing the main valve element 3 against the valve seat 14, so that the primary control surface 32 closes the fluid path between the inlet orifice 11 and the outlet orifice 12. At the same time, the secondary control surface 22 contacts the primary pressure balance orifice 31 to close the outlet orifice 12 and another fluid path between the inlet orifice 11 and the fluid chamber 5. The secondary pressure balance orifice 24 and the pressure balance channel 21 fluidly connect the fluid chamber 5 to the inlet orifice 11.

[0052] Figure 3b The valve is shown in a partially pressure balanced position. Here, the stepper motor 4 has moved the control element 2 upwards so that the secondary control surface 22 no longer contacts the main pressure balanced orifice 31. Both the inlet orifice 11 and the outlet orifice 12 are in communication with the fluid chamber 5 via the secondary pressure balanced orifice 24 and the pressure balanced channel 21. The pressure inside the fluid chamber 5 is determined by the difference between the pressure difference occurring between the inlet orifice 11 and the secondary balanced orifice 24 on one side and the pressure difference occurring between the outlet orifice 12 and the secondary balanced orifice 24 on the other side. Since, depending on the position of the control element 2 in the main valve element 3, the pressure difference between the inlet orifice 11 and the secondary balanced orifice 24 can be greater than the pressure difference between the outlet orifice 12 and the secondary balanced orifice 24, the pressure inside the fluid chamber 5 can be closer to the pressure at the outlet orifice 12 than the pressure at the inlet orifice 11.

[0053] Figure 3cThe valve is shown in a fully pressure balanced position. The stepper motor 4 has moved the control element 2 further upwards so that the secondary stop 23 contacts the primary stop 33. Since the stops 23, 33 can contact each other, no fluid flow or only a negligible fluid flow can pass through the stops 23, 33, so that only the outlet orifice 12 is in communication with the fluid chamber 5 via the secondary pressure balanced orifice 24 and the pressure balanced channel 21. The pressure inside the fluid chamber 5 is determined by the pressure difference occurring between the outlet orifice 12 and the secondary balanced orifice 24. The pressure inside the fluid chamber 5 can be close to or equal to the pressure at the outlet orifice 12. The valve is now fully pressure balanced, so that the force required to lift the main valve element 3 from the valve seat 14 is minimized. In order to obtain a fully balanced state, the area on which the pressure on the fluid chamber 5 side of the main valve element 3 and / or the control element 2 and the area on which the pressure on the outlet orifice 12 side acts can be selected to be equal.

[0054] Figure 3d The valve is shown in a fully open position. The control element 2 has lifted the main valve element 3 so that the main control surface 32 no longer contacts the valve seat 14. In this position, fluid flow between the inlet orifice 11 and the outlet orifice 12 encounters minimal resistance.

[0055] Figure 4 An enlarged cross-sectional view of a second embodiment of the invention is shown. Here, as in the previous examples, the control element 2 is slidable relative to the main valve element 3. The control element 2 comprises a large diameter cylindrical portion 25 and a small diameter cylindrical or conical portion 26. The two sections 25, 26 may extend over almost the entire length of the control element 2. As an example, the two cylindrical portions may extend over 80% or 90% or more of the length of the control element 2. The term "cylindrical" is to be understood broadly throughout the specification, unless otherwise stated, such that the cylindrical portions 25, 26 may contain fluid channels and / or grooves or other features, which may represent some deviation from the perfect cylindrical form. Although in Figure 4 It is not clearly visible in the enlarged view of the valve, but the large diameter cylindrical portion 25 extends over a greater distance in the axial direction of the valve than the small diameter cylindrical or conical portion 26. The axial direction of the valve may correspond to Figure 4 vertical direction.

[0056] As in the previous embodiment, a secondary pressure balancing orifice 24 is provided. The pressure balancing orifice 24 is located between the large diameter cylindrical portion 25 and the small diameter cylindrical or conical portion 26. Alternatively or additionally, the secondary pressure balancing orifice 24 may be located at the small diameter cylindrical or conical portion 26. In any case, the pressure balancing passage 21 is connected to the secondary pressure balancing orifice 24 to be connected as follows: Figure 5a to Figure 5cA fluid connection is shown between the fluid chamber 5 at the top of the control element 2 and the bottom of the control element 2 (corresponding to the secondary control surface 22 of the control element 2). A fluid conduit 36 ​​is provided for fluidly connecting the inlet aperture 11 to the interior of the main valve element 3.

[0057] Figure 5a to Figure 5c A second embodiment of the present invention is shown in cross-sectional views at various valve locations. Figure 5a The valve is shown in a fully closed position. Here, the stepper motor 4 has pushed the control element 2 to its lowest position, effectively pushing the main valve element 3 against the valve seat 14, so that the primary control surface 32 closes the fluid path between the inlet orifice 11 and the outlet orifice 12. At the same time, the secondary control surface 22 contacts the primary pressure balance orifice 31 to close the outlet orifice 12 and another fluid path between the inlet orifice 11 and the fluid chamber 5. The secondary pressure balance orifice 24 and the pressure balance channel 21 fluidly connect the fluid chamber 5 to the inlet orifice 11.

[0058] Figure 5b shows the valve in the pressure balanced position. Figure 5a Compared to the situation shown in FIG. 1 , the stepper motor 4 has moved the control element 2 upward. The secondary control surface 22 no longer contacts the primary pressure balancing orifice 31. Both the inlet orifice 11 and the outlet orifice 12 are in communication with the fluid chamber 5 via the secondary pressure balancing orifice 24 and the pressure balancing channel 21. The pressure inside the fluid chamber 5 is determined by the difference between the pressure difference occurring between the inlet orifice 11 and the secondary balancing orifice 24 on one side and the pressure difference occurring between the outlet orifice 12 and the secondary balancing orifice 24 on the other side. Since the pressure difference between the inlet orifice 11 and the secondary balancing orifice 24 can be greater than the pressure difference between the outlet orifice 12 and the secondary balancing orifice 24, the pressure inside the fluid chamber 5 can be closer to the pressure at the outlet orifice 12 than the pressure at the inlet orifice 11. Since the areas over which the pressure at the fluid chamber 5 side and the pressure at the outlet orifice 12 side act on the control element 2 and / or the main valve element 3 can be selected to be equal, the resultant forces on the control element 2 and / or the main valve element 3 are balanced, so that at least partial pressure balance can occur.

[0059] Figure 5c The valve is shown in a fully open position. The stepper motor 4 has moved the control element 2 further upwards so that the primary control surface 32 no longer contacts the valve seat 14. In this position, fluid flow between the inlet orifice 11 and the outlet orifice 12 encounters minimal resistance.

[0060] As a main difference between the first embodiment and the second embodiment, in the second embodiment, the stoppers 23, 33 are located close to the end positions of the main valve element 3 and the control element 2 opposite to the secondary control surface 22. Figure 5aThe stops 23, 33 are shown as being spaced apart, and in Figure 5b and Figure 5c The middle secondary stop 23 contacts the main stop 33. By contacting the stops 23, 33 of the control element 2 and the main valve element 3, the control element 2 can exert a force on the main valve element 3 to move both elements 2, 3 towards the stepper motor 4.

[0061] Figure 6 An enlarged cross-sectional view of a third embodiment of the present invention is shown. Again, as in the previous embodiment, the control element 2 is slidable relative to the main valve element 3. In the third embodiment, the control element 2 includes a large diameter cylindrical portion 25, a small diameter cylindrical or conical portion 26, a medium diameter cylindrical portion 27, and a short large diameter cylindrical portion 28. The large diameter cylindrical portion 25 extends over a greater distance in the axial direction of the valve than the small diameter cylindrical or conical portion 26, and can represent the longest portion of the control element 2. The medium diameter cylindrical portion 27 is located between the large diameter cylindrical portion 25 and the short large diameter cylindrical portion 28. The large diameter cylindrical portion 25 and the short large diameter cylindrical portion 28 can have equal diameters. The diameters mentioned refer to the outer diameter of a given portion, as the inner diameters of the portions can be the same.

[0062] Another secondary pressure balancing orifice 24' is provided at the short large diameter cylindrical portion 28, and the pressure balancing passage 21 is connected to the other secondary pressure balancing orifice 24'. Alternatively or additionally, the other secondary pressure balancing orifice 24' may be located at the small diameter cylindrical or conical portion 26.

[0063] The interior of the main valve element 3 includes an inner small diameter cylindrical portion 38 and an inner large diameter cylindrical portion 39. The inner small diameter cylindrical portion 38 may be longer than the inner large diameter cylindrical portion 39 in the axial direction of the main valve element. The axial distance between the inner small diameter cylindrical portion 38 of the main valve element 3 and the short large diameter cylindrical portion 28 of the control element 2 defines a fluid flow path between the inlet orifice 11 and the other secondary pressure balance orifice 24' and / or the outlet orifice 12. The closer the edge of the inner small diameter cylindrical portion 38 is to the edge of the short large diameter cylindrical portion 28, the greater the flow resistance to the fluid flow between the inlet orifice 11 and the other secondary pressure balance orifice 24' and / or the outlet orifice.

[0064] In the second and third embodiments, the secondary stopper 23 of the control element 2 is arranged opposite to the small-diameter cylindrical or conical portion 26 for contacting the primary stopper 33 of the main valve element 3 .

[0065] Figures 7a to 7d A third embodiment of the present invention is shown in cross-sectional views at various valve positions. Figure 7aThe valve is shown in a fully closed position. Here, the stepper motor 4 has pushed the control element 2 to its lowest position, thereby pushing the main valve element 3 against the valve seat 14, so that the primary control surface 32 closes the fluid path between the inlet orifice 11 and the outlet orifice 12. At the same time, the secondary control surface 22 contacts the primary pressure balance orifice 31 to close the outlet orifice 12 and another fluid path between the inlet orifice 11 and the fluid chamber 5. Another secondary pressure balance orifice 24' and the pressure balance channel 21 fluidly connect the fluid chamber 5 to the inlet orifice 11.

[0066] In the case of the third embodiment, the distance A between the inner small diameter cylindrical portion 38 and the short large diameter cylindrical portion 28 at least partially defines the fluid passage from the inlet orifice 11 to the outlet orifice 12. Figure 7a In the situation shown, the distance A is at its maximum, with the secondary control surface 22 contacting the primary pressure balance orifice 31. The outlet 12 is not in communication with the fluid chamber 5.

[0067] Figure 7b The valve is shown in a partially pressure balanced position. Here, the stepper motor 4 has moved the control element 2 upwards so that the secondary control surface 22 no longer contacts the primary pressure balanced orifice 31. Both the inlet orifice 11 and the outlet orifice 12 are in communication with the fluid chamber 5 via the secondary pressure balanced orifice 24' and the pressure balanced channel 21. The pressure inside the fluid chamber 5 is determined by the difference between the pressure difference occurring between the inlet orifice 11 and the secondary balanced orifice 24 on one side and the pressure difference occurring between the outlet orifice 12 and the secondary balanced orifice 24 on the other side. Since the pressure difference between the inlet orifice 11 and the secondary balanced orifice 24 can be greater than the pressure difference between the outlet orifice 12 and the secondary balanced orifice 24, the pressure inside the fluid chamber 5 can be closer to the pressure at the outlet orifice 12 than the pressure at the inlet orifice 11.

[0068] Figure 7c The valve is shown in a fully pressure balanced position. The stepper motor 4 has moved the control element 2 further upwards so that the secondary stop 23 contacts the primary stop 33. The pressure inside the fluid chamber 5 is determined by the pressure difference occurring between the outlet orifice 12 and the secondary balancing orifice 24. The pressure inside the fluid chamber 5 may approach or be equal to the pressure at the outlet orifice 12. The valve is now at least partially pressure balanced, because the flow from the inlet orifice 11 towards the further secondary orifice 24' is minimized, so that the force required to lift the main valve element 3 from the valve seat 14 is minimized.

[0069] Figure 7d The valve is shown in a fully open position. The control element 2 has lifted the main valve element 3 so that the main control surface 32 no longer contacts the valve seat 14. In this position, fluid flow between the inlet orifice 11 and the outlet orifice 12 encounters minimal resistance.

[0070] Figure 8 A cross-sectional view of a fourth embodiment of the invention is shown. The main difference between the fourth embodiment and the previous embodiments is that the fourth embodiment comprises a non-return valve 6 having a spring-loaded spherical valve element within the control element 2. The main valve element 3 comprises a main pressure balancing orifice 31, but without the previously shown fluid conduits 36, 37 for fluidly connecting the inlet orifice 11 to the interior of the main valve element 3. The control element 2 comprises a non-return valve 6.

[0071] Figures 9a to 9c A fourth embodiment of the present invention is shown in cross-sectional views at various valve locations. Figure 9a The valve is shown in a fully closed position. Here, the stepper motor 4 has pushed the control element 2 to its lowest position, effectively pushing the main valve element 3 against the valve seat 14, so that the primary control surface 32 closes the fluid path between the inlet orifice 11 and the outlet orifice 12. At the same time, the secondary control surface 22 contacts the primary pressure balance orifice 31 to close the other fluid path between the outlet orifice 12 and the fluid chamber 5.

[0072] Figure 9b The valve is shown in a reverse flow condition. A high pressure now exists at the outlet orifice 12 and a low pressure exists at the inlet orifice 11. The high pressure acts on the non-return valve 6 so that a pressure balance can occur through the non-return valve 6. The secondary control surface 22 can no longer contact the main pressure balance orifice 31. The outlet orifice 12 is connected to the fluid chamber 5 via the pressure balance channel 21. The pressure balance channel 21 can include a secondary pressure balance orifice 24 of the control element 2 and / or a conduit extending in the axial direction in the control element 2. The spring of the non-return valve 6 can be arranged in the pressure balance channel 21. The pressure inside the fluid chamber 5 can be close to or equal to the pressure at the outlet orifice 12.

[0073] Fig.9c The valve is shown in a fully open position. The stepper motor 4 has moved the control element 2 upward so that the primary control surface 32 no longer contacts the valve seat 14. In this position, fluid flow between the inlet orifice 11 and the outlet orifice 12 encounters minimal resistance. Since the primary pressure balance orifice 31 is not in contact with the secondary control surface 22, the pressure balance channel 21 fluidly connects the fluid chamber 5 to the outlet orifice 12.

[0074] Fig.10 Flow curves describing the flow characteristics of various embodiments are shown. The diagram shows the valve opening given in percentage versus the valve lift given in percentage. Here, the valve lift may refer to the lift of the aforementioned control element 2. The solid line shows the flow curve of the first embodiment, the dashed line shows the flow curve of the second embodiment, the dotted line shows the flow curve of the third embodiment, and the chain line shows the flow curve of the fourth embodiment.

[0075] Fig.11 A system diagram with possible applications of the valve according to the invention is shown. When the valve is used in the context of refrigeration and / or air conditioning applications, position 1) represents the use of the valve as a bypass for reducing pressure drop or as a steam control device for controlling the condenser temperature. When the valve is used in position 2), the valve can be used for the same purpose.

[0076] When the valve is used in position 3), the valve can provide control of the superheat process or provide a boost function for rapid air conditioning cooling. When the valve is used in position 4), the valve can again provide control of the superheat process or provide a rapid charging boost function.

[0077] Fig.12 A cross-sectional view of a fifth embodiment of the invention is shown. The main difference between the fifth embodiment and the previous embodiments is that the fluid passage 21 can be blocked at only one position, namely at the main pressure balancing orifice 31 of the main valve element 3, in a state where the pressure balancing orifice 31 is in contact with the secondary control surface 22 of the control element 2.

[0078] As with all embodiments of the present invention, it is conceivable that the fluid chamber 5 is arranged in direct contact with the uppermost parts of the control element 2 and the main valve element 3. The control element 2 and the main valve element 3 can each be integrally formed so that they represent a single component. Likewise, as with other embodiments of the present invention, the control element 2 can be at least partially hollow or include radial ducts and / or axial ducts to allow pressure equalization through the control element 2.

[0079] In the fifth embodiment, the secondary stop 23 of the control element 2 and the primary stop 33 of the main valve element 3 are arranged at or near the uppermost parts of the control element 2 and the main valve element 3. The two stops 23, 33 are shown in contact with each other so that the control element 2 can exert a force in an upward, i.e., opening direction, at the valve element 3. The valve is shown in a fully open position, with the outlet orifice 12 and the inlet orifice 11 in fluid communication with each other.

[0080] Figures 13a to 13c A fifth embodiment of the present invention is shown in cross-sectional views at various valve positions. Fig.13a The valve is shown in a fully closed position. Here, the stepper motor 4 has pushed the control element 2 to its lowest position, effectively pushing the main valve element 3 against the valve seat 14, so that the primary control surface 32 closes the fluid path between the inlet orifice 11 and the outlet orifice 12. At the same time, the secondary control surface 22 contacts the primary pressure balance orifice 31 to close the fluid path between the outlet orifice 12 and the fluid chamber 5.

[0081] Fig.13bThe valve is shown in a state in which a high pressure may exist at the outlet orifice 12 and a low pressure may exist at the inlet orifice 11. The control element 2 has been lifted by the stepper motor 4 so that the primary pressure balancing orifice 31 is no longer closed by the secondary control surface 22. Pressure can propagate freely between the outlet orifice 12 and the fluid chamber 5, effectively balancing the valve.

[0082] The pressure balance channel 21 may include a secondary pressure balance orifice 24 of the control element 2 and / or a conduit extending in the axial direction within the control element 2 .

[0083] The main valve element 3 comprises only an axial conduit in which the control element 2 is slidably arranged. This means that no radial openings are provided in the main valve element 3 .

[0084] Fig.13c The valve is shown in the fully open position. The stepper motor 4 has moved the control element 2 upwards so that the main control surface 32 no longer contacts the valve seat 14.

[0085] The secondary stopper 23 contacts the main stopper 33 to pull the main valve element 3 together with the control element 2 .

[0086] In this position, fluid flow between the inlet orifice 11 and the outlet orifice 12 encounters minimal resistance. Since the primary pressure balance orifice 31 is not in contact with the secondary control surface 22 , the pressure balance passage 21 fluidly connects the fluid chamber 5 to the outlet orifice 12 .

[0087] Figures 14a to 14c is a cross-sectional view of the sixth embodiment of the present invention at various valve positions. The main difference between the sixth embodiment and the first to fifth embodiments is that the pressure balance channel 21 is not located radially inside the control element 2, but between the outer face of the control element 2 and the inner face of the main valve element 3. The control element 2 may include one or more solid parts without any conduits. The main valve element 3 includes a main pressure balance orifice 31. A fluid conduit 36 ​​may be provided for fluidly connecting the interior of the main valve element 3 to the fluid chamber 5.

[0088] Fig.14aThe valve is shown in a fully closed position. Here, the previously shown stepper motor 4 has pushed the control element 2 to its lowest position, thereby effectively pushing the main valve element 3 against the valve seat 14, so that the primary control surface 32 closes the fluid path between the inlet orifice 11 and the outlet orifice 12. At the same time, the secondary control surface 22 contacts the main pressure balance orifice 31 to close the fluid path between the outlet orifice 12 and the fluid chamber 5. The pressure P_in acting at the inlet orifice 11 can be propagated to the fluid chamber 5 through the secondary pressure balance channel 21'. The secondary pressure balance channel 21' can be arranged between the radial outer surface of the main valve element 3 and the inner surface of the valve housing 1. The secondary pressure balance channel 21' can be sized to allow only a slow pressure balance between the fluid chamber 5 and the inlet orifice 11. In particular, the secondary pressure balance channel 21' can be sized so that the pressure balance across the secondary pressure balance channel 21' is at least one order of magnitude or several orders of magnitude slower than the pressure balance across the fully opened main pressure balance channel 21. The valve effectively separates the pressure P_in at the inlet orifice 11 from the pressure P_out at the outlet orifice 12. The main valve element 3 may be considered to be unbalanced.

[0089] Fig.14b The valve is shown in a pressure balanced position. The secondary control surface 22 may no longer contact the primary pressure balanced orifice 31 . The outlet orifice 12 communicates with the fluid chamber 5 via the pressure balanced channel 21 .

[0090] Fig.14c The valve is shown in a fully open position. The stepper motor 4 has moved the control element 2 upwards so that the primary control surface 32 no longer contacts the valve seat 14. In this position, the fluid flow between the inlet orifice 11 and the outlet orifice 12 encounters minimal resistance. Since the primary pressure balance orifice 31 is not in contact with the secondary control surface 22, the pressure balance channel 21 connects the fluid chamber 5 fluid to the outlet orifice 12. The invention is not limited to this embodiment, but can be adapted in various ways. All features disclosed in the claims, the description and the drawings, including construction details and spatial arrangements, can be relevant to the invention individually or in various combinations with each other.

[0091] Reference numerals

[0092] 1 Housing

[0093] 2 Control elements

[0094] 3 Main valve element

[0095] 4 Stepper Motors

[0096] 5 Fluid Chamber

[0097] 6 Check valve

[0098] 7 Spring

[0099] 11 Inlet opening

[0100] 12 Outlet orifice

[0101] 13 Installation

[0102] 14 Valve seat

[0103] 21. Pressure balance channel

[0104] 21' Secondary pressure balance channel 22 Secondary control surface

[0105] 23 Secondary stop

[0106] 24 Secondary pressure balance orifice

[0107] 24' Another secondary pressure balance orifice

[0108] 25 Large diameter cylindrical part

[0109] 26 Small diameter cylindrical or conical parts

[0110] 27 Medium diameter cylindrical part

[0111] 28 Short large diameter cylindrical section

[0112] 31 Main pressure balance orifice

[0113] 32 Main Control Surfaces

[0114] 33 Main stopper

[0115] 34 External main valve element part

[0116] 35 Internal main valve component part

[0117] 36, 37 Fluid conduit

[0118] 38 Inner small diameter cylindrical part

[0119] 39 Inner large diameter cylindrical part

Claims

1. An active balancing valve actuated by a stepper motor (4) for refrigeration and / or air conditioning applications, the active balancing valve comprising: A valve housing (1) having an inlet opening (11), an outlet opening (12) and a mounting portion (13), a main valve element (3) having a main pressure balancing orifice (31), and A control element (2) which is actuated by the stepper motor (4) and at least partially defines a pressure balance channel (21), wherein: Each element is slidable within the valve housing (1) and comprises a control surface for controlling the fluid flow between the inlet orifice (11) and the outlet orifice (12) and / or the pressure propagation between the outlet orifice (12) and the interior of the main valve element (3), and wherein, The control element (2) closes the main pressure balance orifice (31) of the main valve element (3) in the closed state of the valve.

2. The active balancing valve according to claim 1, characterized in that: The control element (2) is at least partially arranged inside the main valve element (3).

3. An active balancing valve according to any one of the preceding claims, characterized in that The control element (2) is capable of sliding relative to the main valve element (3), wherein preferably, the sliding distance corresponds to the distance between the position where the secondary control surface (22) of the control element (2) contacts the main pressure balance orifice (31) and the position where the secondary stop portion (23) of the control element (2) contacts the main stop portion (33) of the main valve element (3).

4. The active balancing valve according to claim 3, characterized in that: The secondary stop (23) and the primary stop (33) are contactable to block the passage of fluid from the inlet aperture (11) to the outlet aperture (12).

5. An active balancing valve according to at least claim 3, characterized in that A secondary pressure balance orifice (24) is arranged in the control element (2) between the secondary control surface (22) and the secondary stop (23) of the control element (2).

6. An active balancing valve according to at least claim 3, characterized in that The main valve element (3) comprises two main valve element parts, wherein an inner main valve element part (35) can be inserted into an outer main valve element part (34) and comprises the main stop (33).

7. An active balancing valve according to at least claim 6, characterized in that The two main valve element parts include fluid conduits (36, 37) for fluidly connecting the inlet aperture (11) to the interior of the inner main valve element part (35).

8. An active balancing valve according to any one of the preceding claims, characterized in that The stepper motor (4) or a part of the stepper motor (4) is arranged at the mounting portion (13).

9. An active balancing valve according to any one of the preceding claims, characterized in that A fluid chamber (5) is provided between the stepper motor (4) on one side and the control element (2) and the main valve element (3) on the other side, and the fluid chamber (5) is fluidically connected to the pressure balance channel (21).

10. An active balancing valve according to any one of the preceding claims, characterized in that A spring (7) is provided for pressing the control element (2) and / or the main valve element (3) in the direction of the outlet opening (12).

11. An active balancing valve according to any one of the preceding claims, characterized in that The control element (2) comprises a non-return valve (6) and / or the main valve element (3) comprises a seal towards the valve housing (1).

12. The active balancing valve according to any one of claims 1, 2 or 8 to 10, characterized in that: The control element (2) is capable of sliding relative to the main valve element (3) and / or the control element (2) comprises a large diameter cylindrical portion (25) and a small diameter cylindrical or conical portion (26), wherein the large diameter cylindrical portion (25) extends over a greater distance in the axial direction of the valve than the small diameter cylindrical or conical portion (26).

13. The active balancing valve according to claim 12, characterized in that: The secondary pressure balancing orifice (24) is arranged at the small diameter cylindrical or conical part (26) or between the large diameter cylindrical part (25) and the small diameter cylindrical or conical part (26), and / or the pressure balancing passage (21) is connected to the secondary pressure balancing orifice (24).

14. The active balancing valve according to any one of claims 1, 2 or 8 to 10, characterized in that: The control element (2) is capable of sliding relative to the main valve element (3) and / or the control element (2) includes a large diameter cylindrical portion (25), a small diameter cylindrical or conical portion (26), a medium diameter cylindrical portion (27), and a short large diameter cylindrical portion (28), wherein the large diameter cylindrical portion (25) extends over a greater distance in the axial direction of the valve than the small diameter cylindrical or conical portion (26), and / or wherein the medium diameter cylindrical portion (27) is located between the large diameter cylindrical portion (25) and the short large diameter cylindrical portion (28).

15. The active balancing valve according to claim 14, characterized in that: Another secondary pressure balancing orifice (24') is provided at the short large diameter cylindrical portion (28), and preferably, the pressure balancing passage (21) is connected to the other secondary pressure balancing orifice (24').

16. The active balancing valve according to claim 14 or 15, characterized in that: The large diameter cylindrical portion (25) and the short large diameter cylindrical portion (28) have the same diameter.

17. The active balancing valve according to any one of claims 14 to 16, characterized in that: The interior of the main valve element (3) includes an inner small diameter cylindrical portion (38) and an inner large diameter cylindrical portion (39), wherein the inner small diameter cylindrical portion (38) is longer than the inner large diameter cylindrical portion (39) along the axial direction of the main valve element.

18. The active balancing valve according to any one of claims 12 to 17, characterized in that: The secondary stop (23) of the control element (2) is arranged opposite to the small diameter cylindrical or conical portion (26) for contacting the main stop (33) of the main valve element (3), and / or a fluid conduit (36) is arranged for fluidly connecting the inlet opening (11) to the interior of the main valve element (3).

19. An active balancing valve according to at least claims 14 and 17, characterized in that The distance between the inner small diameter cylindrical portion (38) and the short large diameter cylindrical portion (28) at least partially defines a fluid passage from the inlet orifice (11) to the outlet orifice (12).

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