Expansion valve, motor vehicle and refrigeration circuit with expansion valve and method for reducing a flow cross-section using an expansion valve

Abstract

An expansion valve comprises: a housing (20) having a valve chamber; a first fluid passage (3) from a first port (3.1) of the expansion valve to a first access (3.2) of a connecting section (21) of the valve chamber; a second fluid passage (4) from a second port (4.1) of the expansion valve to a second access (4.2) of the connecting section; a valve element (2) arranged in the valve chamber such that, in an open position, it releases an opening cross-section of the second access and, in at least one regulating position, releases a smaller opening cross-section of the second access; wherein the valve chamber has a control section (6) on a side of the valve member opposite the connecting section; wherein the expansion valve further comprises: a first valve (9) which is configured to, to connect the control section to the first port in a first operating mode and to connect the control section to the second port instead in a second operating mode; a second valve (10) which is configured to to connect a pilot passage, which is set up to drain fluid from the control section, to the second port in the first operating mode and to the first port instead in the second operating mode; a control element (5); and an actuator (1) for adjusting the control element; wherein the control element is configured to reversibly close the pilot passage.

Description

[0001] The present invention relates to an expansion valve, a motor vehicle and a refrigeration circuit with the expansion valve as well as a method for variably reducing a flow cross-section using the expansion valve.

[0002] An object of the present invention is to improve an expansion valve, a motor vehicle or a refrigeration circuit or its operation.

[0003] This object is achieved by an expansion valve having the features of claim 1. Claims 12 and 13 protect a motor vehicle or a refrigeration circuit with at least one expansion valve described herein, or a method for variably reducing a flow cross-section using an expansion valve described herein. The subclaims relate to advantageous developments.

[0004] According to one embodiment of the present invention, an expansion valve comprises: - a single or multi-part housing having a valve chamber; - a first single- or multi-channel fluid passage from a first single- or multi-channel connection, preferably an external connection, of the expansion valve to a first single- or multi-channel access of a connecting section of the valve chamber; and - a second single- or multi-channel fluid passage from a second single- or multi-channel connection, preferably external connection, of the expansion valve to a second single- or multi-channel access of the connecting section.

[0005] According to one embodiment of the present invention, the expansion valve has a valve member which is preferably arranged movably in the valve chamber in such a way that it - in an open position, releases a (first) opening cross-section of the second access, in particular is spaced apart from the second access, so that the first and second connection or first and second access communicate fluidically with each other via the connecting section; and - in at least one regulating position, releases an opening cross-section of the second access which is smaller than the (first) opening cross-section of the second access which the valve member releases in the open position, in particular is spaced less from the second connection than in the open position, so that the first and second connection or first and second access communicate with each other fluidically via the connecting section and in the process a flow cross-section, which in one embodiment is minimal, between the first and second connection or first and second access or this connecting section or this fluidic connection or communication is or is reduced compared to the open position, preferably - in a closed position, closes the second access or blocks fluidic communication between the first and second connection or first and second access via the connecting section; and / or in two or more different regulating positions, releases (in each case) different opening cross-sections of the second access, which are (in each case) smaller than the (first) opening cross-section of the second access that the valve member releases in the open position, in particular different and (in each case) closer to the second connection, so that the first and second connection or first and second access communicate with each other fluidic via the connecting section and in doing so a flow cross-section, which in one embodiment is minimal, is maintained between the first and second connection or first and second access or this connecting section or this fluidic connection orCommunication is reduced to different degrees compared to disclosure.

[0006] As a result, in one embodiment, with the aid of the expansion valve, a flow cross-section - in one embodiment minimal - between the first and second connection can be variably, preferably controlled or regulated, reduced, preferably (also) closed or blocked. By means of this local constriction of the flow cross-section, the expansion valve in one embodiment can (variably) reduce the pressure of the fluid flowing through and thus preferably bring about an increase in volume or expansion, wherein the pressure reduction can preferably take place, at least substantially, without dissipating work and, ideally, also without dissipating heat or, thermodynamically, at least approximately, isenthalpically. In general, an expansion valve described here can be a throttle valve.

[0007] According to one embodiment of the present invention, the valve chamber has a control section on a side of the valve member opposite the connecting section.

[0008] As a result, in one embodiment, the valve member can (likewise) be subjected to fluid (pressure) on a side opposite the first and second access or connecting section, which counteracts an opening force as a result of pressure applied to the first and second connection or first and second access or causes a corresponding closing force.

[0009] According to one embodiment of the present invention, the expansion valve further comprises: a single- or multi-channel pilot passage arranged to discharge fluid from the control section; an actuator; and an actuator for adjusting the actuator; wherein the actuator is adapted to reversibly close the pilot passage.

[0010] This allows a pilot-operated expansion valve to be implemented in one embodiment, thereby advantageously improving installation space requirements and / or energy consumption and / or precision, reliability, and / or service life, particularly through a smaller actuator. In general, the expansion valve in one embodiment is a pilot-operated expansion valve.

[0011] If the first port of the expansion valve is subject to a higher pressure (compared to the second port), this pressure can be used in one embodiment in the control section to reduce the flow or opening cross-section or to close it, and fluid can be selectively discharged to the second port via the pilot passage. However, if the second port of the expansion valve is subject to a higher pressure (compared to the first port), this is not possible.

[0012] In particular, the expansion valve according to an embodiment of the present invention comprises: a first valve that in a first operating mode, connects the control section, in particular fluidically, to the first connection and preferably fluidically separates the control section and the second connection; and in a second operating mode, instead, the control section, in particular fluidically, connects to the second connection and preferably fluidically separates the control section and the first connection; or is set up or used for this purpose; and a second valve that in the first operating mode, the pilot passage connects, in particular fluidically, to the second connection and preferably fluidically separates the first connection and the pilot passage; and in the second operating mode, the pilot passage instead connects, in particular fluidically, to the first connection and preferably fluidically separates the second connection and the pilot passage; or is set up or used for this purpose.

[0013] If, in the first operating mode, the higher pressure is present at the first connection of the expansion valve (compared to the second connection), in one embodiment the first valve connects the first connection to the control section and the second valve connects the pilot passage to the second connection, so that - when the pilot passage is opened by the actuator - fluid (pressure) can escape from the control section to the second connection, so that the closing force caused by fluid (pressure) in the control section is reduced and the expansion valve opens (increasingly).

[0014] Conversely, if in the second operating mode the higher pressure is present at the second connection of the expansion valve (compared to the first connection), in one embodiment the first valve connects the second connection to the control section instead and the second valve connects the pilot passage to the first connection instead of the second connection, so that - when the pilot passage is opened by the actuator - fluid (pressure) can escape from the control section to the first connection, so that in turn the closing force caused by fluid (pressure) in the control section is reduced and the expansion valve opens (increasingly).

[0015] Thus, in one embodiment, a bidirectional pilot-operated expansion valve can advantageously be provided. Accordingly, in one embodiment, a flow direction of the expansion valve in the first operating mode and a flow direction of the expansion valve in the second operating mode are opposite. Preferably, in the first operating mode, the higher (fluid) pressure is present at the first port or in the first fluid passage (compared to the second port or the second fluid passage), and conversely, in the second operating mode, the higher (fluid) pressure is present at the second port or in the second fluid passage (compared to the first port or the first fluid passage).

[0016] In one embodiment, the valve member has a movable, preferably movably mounted or guided, piston, which in a further development is arranged, in particular mounted or guided, in the valve chamber in such a way that a movement of the piston - in a closing direction, a volume of the control section is increased and a volume of the connecting section is reduced and - in an opening direction, a volume of the control section is reduced and a volume of the connecting section is increased, can in particular be such a piston.

[0017] This allows a particularly advantageous design, sealing, actuation and / or adjustment kinematics to be realized in one version.

[0018] In a further development, the piston has a tapered section, preferably on the connecting section side, preferably a front section, in a preferred development a control cone, so that with decreasing distance of the piston to the second access, a free or opening cross section of the second access through the piston or its tapered section or control cone is increasingly reduced, or the piston or tapered section or control cone is configured for this purpose.

[0019] Additionally or alternatively, in a further development, the piston has the pilot passage, which has or connects a single- or multi-channel inlet and a single- or multi-channel outlet, wherein the actuator is designed to reversibly close this inlet.

[0020] This allows a particularly advantageous design, sealing, actuation and / or adjustment kinematics to be realized in one version.

[0021] In one embodiment, the outlet is arranged on a circumferential surface of the piston. Additionally or alternatively, in one embodiment, the inlet is arranged on an end face of the piston, preferably on the control section side.

[0022] This allows a particularly advantageous design, sealing, actuation and / or adjustment kinematics to be realized in one version.

[0023] In one embodiment, the piston is (reversibly) axially displaceable in the valve chamber, in particular in the closing and opening direction.

[0024] This allows an advantageous design and / or adjustment kinematics to be realized in one version.

[0025] Additionally or alternatively, in one embodiment, the piston has a first control section-side section with a first, in particular maximum, outer circumference and a second connection section-side section with a smaller second outer circumference.

[0026] This allows an advantageous design, sealing and / or adjustment kinematics to be realized in one version.

[0027] In one embodiment, the actuator is (reversibly) axially displaceable in the valve chamber.

[0028] This allows an advantageous design, sealing, actuation and / or adjustment kinematics to be realized in one version.

[0029] In one embodiment, the first access is arranged on a peripheral surface of the connecting section. Additionally or alternatively, in one embodiment, the second access is arranged on an end face of the connecting section.

[0030] As a result, an advantageous, in particular more compact, design and / or advantageous sealing, actuation and / or adjustment kinematics can be realized in one embodiment.

[0031] In one embodiment, the first valve has a single- or multi-channel outlet passage to the control section. Additionally or alternatively, in one embodiment, the first valve has a single- or multi-channel first inlet passage from the connecting section, preferably a circumferential surface of the connecting section, or from the first fluid passage. Additionally or alternatively, in one embodiment, the first valve has a single- or multi-channel second inlet passage from the second fluid passage.

[0032] Additionally or alternatively, in one embodiment, the second valve has a single- or multi-channel inlet passage from the valve chamber, preferably its peripheral surface, wherein this inlet passage preferably communicates fluidically with the outlet of the piston or the pilot passage, in a further development via a single- or multi-channel annular groove of the valve chamber. Additionally or alternatively, in one embodiment, the second valve has a single- or multi-channel first outlet passage to the second fluid passage. Additionally or alternatively, in one embodiment, the second valve has a single- or multi-channel second outlet passage to the first fluid passage.

[0033] As a result, an advantageous, in particular more compact, design and / or advantageous sealing, actuation and / or adjustment kinematics can be realized in one embodiment.

[0034] In one embodiment, one or more of the inlet and / or outlet passages of the first and / or second valve are formed at least partially or sectionally in or through the housing, preferably formed integrally with the housing. Additionally or alternatively, in one embodiment, the first valve has a separate valve body which is fastened to, preferably in, the housing and / or in which the first and / or second inlet passage and / or the outlet passage of the first valve is formed at least partially or sectionally. Additionally or alternatively, in one embodiment, the second valve has a separate valve body which is fastened to, preferably in, the housing and / or in which the inlet passage and / or the first and / or second outlet passage of the second valve is formed at least partially or sectionally.

[0035] As a result, an advantageous, in particular more compact, design and / or advantageous sealing, actuation and / or adjustment kinematics can be realized in one embodiment.

[0036] In one embodiment, one or more orifices are arranged in the outlet passage of the first valve or between the first valve and the control section.

[0037] In one embodiment, this allows an advantageous pressurization to be set in the control section and, in particular, the function of the expansion valve to be improved.

[0038] In one embodiment, the first valve is a preferably automatic, pressure-controlled valve and / or shuttle valve with a switching function. In a particularly preferred embodiment, it is controlled or adjusted by the pressure applied to the first and / or second connection of the expansion valve, in a further development the pressure in its first and / or second inlet passage, preferably a pressure difference between the first and second connection of the expansion valve or first and second inlet passage, preferably at higher pressure at the first connection of the expansion valve in such a way that it connects the first connection of the expansion valve to the control section (fluidically) and at higher pressure at the second connection of the expansion valve in such a way that it connects the second connection of the expansion valve to the control section (fluidically) or is designed to do so.

[0039] Additionally or alternatively, in one embodiment, the second valve is a preferably automatic, pressure-controlled valve and / or shuttle valve with a switching function or negation. In a particularly preferred embodiment, it is controlled or adjusted by the pressure applied to the first and / or second connection of the expansion valve, in a further development the pressure in its first and / or second outlet passage, preferably a pressure difference between the first and second connection of the expansion valve or first and second outlet passage, preferably at higher pressure at the first connection in such a way that it connects the pilot passage to the second connection of the expansion valve (fluidically) and at higher pressure at the second connection of the expansion valve in such a way that it connects the pilot passage to the first connection of the expansion valve (fluidically), or is designed to do so.

[0040] In one embodiment, this allows an advantageous, particularly reliable and / or low-energy, adjustment of the first or second valve to be realized.

[0041] In one embodiment, the actuator can be adjusted continuously or in several, preferably at least three, stages, or the actuator is configured for this purpose. In one embodiment, the actuator comprises a stepper motor.

[0042] In this way, an advantageous, particularly precise and / or rapid, actuation can be realized in one embodiment.

[0043] An expansion valve described here can, in particular due to the operating conditions, structural, thermodynamic and / or control-related requirements or boundary conditions, be used with particular advantage in motor vehicles and / or refrigeration circuits, in particular in refrigeration circuits of motor vehicles and / or for the variable, in particular controlled or regulated, (reversible) reduction of a flow cross-section of a refrigerant (flow).

[0044] According to one embodiment of the present invention, in or after a method for variably reducing a flow cross-section, in a preferred development of a refrigerant (flow), using an expansion valve described here to enlarge a flow cross-section or opening cross-section of the second access, the actuator removes the control element from the pilot passage or its inlet, in one development for different lengths of time and / or different distances. Additionally or alternatively, according to one embodiment of the present invention, to reduce a flow cross-section or opening cross-section of the second access, in a development to close the expansion valve, the actuator adjusts the control element to close the pilot passage or close its inlet.

[0045] In one embodiment, the expansion valve is operated temporarily in the first operating mode and temporarily in the second operating mode, wherein a flow direction of the expansion valve in the first operating mode and a flow direction of the expansion valve in the second operating mode are opposite, preferably in the first operating mode the higher (fluid) pressure is applied to the first connection or in the first fluid passage (compared to the second connection or the second fluid passage) and conversely in the second operating mode the higher (fluid) pressure is applied to the second connection or in the second fluid passage (compared to the first connection or the first fluid passage).

[0046] Further advantages and features emerge from the subclaims and the exemplary embodiments. The following shows, partly schematically: Fig. 1: a closed expansion valve of a motor vehicle and / or refrigeration circuit according to an embodiment of the present invention in a first operating mode; Fig. 2: the partially open expansion valve in the first operating mode; Fig. 3: the closed expansion valve in a second operating mode; Fig. 4: the partially opened expansion valve in the second operating mode; and Fig. 5: a method for selectively influencing a fluid flow using the expansion valve according to an embodiment of the present invention.

[0047] Fig. 1 shows a closed expansion valve of a motor vehicle and / or refrigeration circuit, in particular a refrigeration circuit of a motor vehicle, indicated only schematically by the reference numeral 100, according to an embodiment of the present invention in a first operating mode in which a higher pressure is present at a first connection 3.1 of the expansion valve than at a second connection 4.1 of the expansion valve.

[0048] The expansion valve has a housing 20 with a valve chamber in which a valve member in the form of a piston 2 is arranged to be axially displaceable.

[0049] The expansion valve or housing has a first fluid passage 3 from the first connection 3.1 of the expansion valve to a first access 3.2 on a peripheral surface of a connecting section 21 of the valve chamber and a second fluid passage 4 from the second connection 4.1 of the expansion valve to a second access 4.2 on an end face of the connecting section.

[0050] The expansion valve further comprises a first valve 9 which, in the first operating mode, fluidically connects the connecting section 21 and thus the first connection 3.1 with the control section 6.

[0051] The expansion valve further comprises a second valve 10 which, in the first operating mode, fluidically connects an outlet 2.2 of a pilot passage 8, which is arranged on a circumferential surface of the piston 2, to the second fluid passage 4 and thus to the second connection 4.1.

[0052] The expansion valve further comprises an actuator in the form of a pin 5, which is axially displaceable in the control section of the valve chamber in the closing and opening direction, and an actuator in the form of a stepper motor 1 for adjusting this actuator.

[0053] The piston 2 has a control cone 11 which in the closed position of the Fig. 1 completely closes the second access 4.2.

[0054] The piston 2 further comprises the pilot or drain passage or bore 8 from a control section-side inlet 2.1 on an end face of the piston to the outlet 2.2.

[0055] In the Fig. In the position shown in Figure 1, the actuator 5 closes this inlet 2.1.

[0056] To gradually open the expansion valve, the actuator or stepper motor 1 slowly moves the actuator 5 away from the inlet 2.1, thus releasing it. This is shown in Fig. 2 illustrated.

[0057] There are also schematically indicated a first, control section-side active surface A1 of the piston 2, the action of which by fluid in the control section 6 causes a load in the closing direction on the piston 2, a second, connection section-side active surface A2 for closing the second access 4.2, the action of which by fluid in the second fluid passage 4 when the second access is closed causes a load in the opening direction on the piston, and a third, connection section-side active surface A3, the action of which by fluid in the connection section 21 when the second access is closed causes a load in the opening direction on the piston 2.

[0058] The piston has a first control section side section 2A with a first outer circumference and a second connection section side section 2B with a smaller second outer circumference.

[0059] The first valve 9 has an outlet passage 9.3 to the control section 6, in which an orifice 7 is arranged, a first inlet passage 9.1 from a peripheral surface of the connecting section 21, and a second inlet passage 9.2 from the second fluid passage 4.

[0060] The second valve 10 has an inlet passage 10.3 from an opening in the peripheral surface of the valve chamber, which communicates with the outlet 2.2 of the pilot passage 8, a first outlet passage 10.1 to the second fluid passage 4 and a second outlet passage 10.2 to the first fluid passage 3.

[0061] Fig. 3, Fig. 4 show in Fig. 1, Fig. 2 correspondingly, the expansion valve in a second operating mode, in which conversely a higher pressure is applied to the second connection 4.1 of the expansion valve than to the first connection 3.1 of the expansion valve, so that a flow direction of the expansion valve in this second operating mode and a flow direction of the expansion valve in the Fig. 1, Fig. 2 illustrated first operating mode are opposite.

[0062] In the second operating mode, the pressure-controlled first shuttle valve 9 with switching function connects the second fluid passage 4 and thus the second connection 4.1 with the control section 6 and the pressure-controlled second shuttle valve 10 with switching function connects the outlet 2.2 of the piston 2 or the pilot passage 8 with the first fluid passage 3 and thus the first connection 3.1.

[0063] When inlet 2.1 is open, fluid (pressure) escapes from control section 6 through pilot passage 8 to second valve 10, which always blocks the passage to the higher pressure level or inlet pressure and opens a passage to the lower pressure level or outlet pressure. The control cone 11 allows the open or opening cross-section and thus also the characteristic curve of the expansion valve to be specifically designed or specified.

[0064] Fig.5 illustrates a method according to an embodiment of the present invention. In a step S10, the system switches to the first operating mode, in a step S20, the expansion valve is successively opened, and in a step S30, it is closed. In a step S40, the system switches to the second operating mode, in a step S50, the expansion valve is successively opened, and in a step S60, it is closed. Of course, other sequences of steps are possible, in particular, multiple opening and closing and / or switching of operating modes.

[0065] In the present disclosure, "has an X" generally does not imply an exhaustive list, but is a shortened form of "has at least one X" and also includes "has two or more Xs" and "has Y in addition to X." Although exemplary embodiments have been explained in the foregoing description, it should be noted that numerous modifications are possible. Furthermore, it should be noted that the exemplary embodiments are merely examples and are not intended to limit the scope, applications, or construction in any way.Rather, the foregoing description provides the person skilled in the art with a guide for the implementation of at least one exemplary embodiment, whereby various changes, in particular with regard to the function and arrangement of the described components, can be made without departing from the scope of protection as it results from the claims and combinations of features equivalent to these. List of reference symbols 1 stepper motor (actuator) 2 pistons (valve member) 2.1 Admission 2.2 Outlet 2A first section 2B second section 3 first fluid passage 3.1 first connection 3.2 First access 4 second fluid passage 4.1 second connection 4.2 second access 5 pin (actuator) 6 Control section of the valve chamber 7 aperture 8 Pilot / drain passage / bore 9 first valve 9.1 first inlet passage of the first valve 9.2 second inlet passage of the first valve 9.3 Drain passage of the first valve 10 second valve 10.1 first drain passage of the second valve 10.2 second drain passage of the second valve 10.3 Inlet passage of the second valve 11 Control cone 20 housings 21 Connecting section of the valve chamber 100 motor vehicles / refrigeration circuit A1 first effective area A2 second effective area A3 third effective area

Claims

[1] Expansion valve, comprising: a housing (20) having a valve chamber; a first fluid passage (3) from a first connection (3.1) of the expansion valve to a first access (3.2) of a connecting section (21) of the valve chamber; a second fluid passage (4) from a second port (4.1) of the expansion valve to a second access (4.2) of the connecting section; a valve member (2) which is arranged in the valve chamber such that in an open position it releases an opening cross-section of the second access and in at least one regulating position it releases a smaller opening cross-section of the second access; wherein the valve chamber has a control section (6) on a side of the valve member opposite the connecting section; wherein the expansion valve further comprises: a first valve (9) which is arranged to in a first operating mode, to connect the control section to the first terminal and in a second mode of operation, to connect the control section to the second terminal instead; a second valve (10) arranged to open a pilot passage arranged to discharge fluid from the control section, in the first operating mode to connect to the second port and in the second operating mode, to be connected to the first terminal instead; an actuator (5); and an actuator (1) for adjusting the actuator; wherein the actuator is adapted to reversibly close the pilot passage. [2] Expansion valve according to claim 1, characterized by that the valve member has a movable piston. [3] Expansion valve according to claim 2, characterized by , that the piston has a tapered section for releasing different cross-sections of the second access; and / or the piston has the pilot passage with an inlet (2.1) and an outlet (2.2), wherein the actuator is adapted to reversibly close the inlet. [4] Expansion valve according to claim 3, characterized by that the outlet is arranged on a circumferential surface of the piston; and / or the inlet is arranged on an end face of the piston. [5] Expansion valve according to one of the preceding claims 2-4, characterized by that the piston is axially displaceable in the valve chamber and / or has a first control section-side section (2A) with a first outer circumference and a second connection section-side section (2B) with a smaller second outer circumference. [6] Expansion valve according to one of the preceding claims, characterized bythat the actuator is axially displaceable in the valve chamber. [7] Expansion valve according to one of the preceding claims, characterized by , that the first access is arranged on a peripheral surface of the connecting section; and / or the second access is arranged on an end face of the connecting section. [8] Expansion valve according to one of the preceding claims, characterized by , that the first valve a discharge passage (9.3) to the control section; and / or a first inlet passage (9.1) from the connecting section or the first fluid passage; and / or a second inlet passage (9.2) from the second fluid passage; and / or the second valve an inlet passage (10.3) from the valve chamber; and / or a first drain passage (10.1) to the second fluid passage; and / or a second drain passage (10.2) to the first fluid passage; has. [9] Expansion valve according to the preceding claim, characterized by that at least one orifice (7) is arranged in the outlet passage of the first valve. [10] Expansion valve according to one of the preceding claims, characterized by , that the first valve is a pressure-controlled valve and / or shuttle valve with a switching function; and / or the second valve is a pressure-controlled valve and / or shuttle valve with switching function. [11] Expansion valve according to one of the preceding claims, characterized bythat the actuator can be adjusted continuously or in several stages by the actuator and / or the actuator has a stepper motor and / or the valve member is arranged in the valve chamber such that it closes the second access in a closed position. [12] Motor vehicle or refrigeration circuit with at least one expansion valve according to one of the preceding claims. [13] Method for variably reducing a flow cross-section using an expansion valve according to one of the preceding claims, wherein, in order to enlarge an opening cross-section of the second access, the actuator removes the actuator from the pilot passage; and / or To reduce an opening cross-section of the second access of the actuator, the actuator is adjusted to close the pilot passage. [14] Method according to the preceding claim, characterized bythat the expansion valve is operated temporarily in the first operating mode and temporarily in the second operating mode, wherein a flow direction of the expansion valve in the first operating mode and a flow direction of the expansion valve in the second operating mode are opposite.

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