DE102016200576A1 - Expansion element and method for controlling or controlling a refrigerant mass flow, use for a refrigeration circuit of a motor vehicle, and motor vehicle - Google Patents

Abstract

The present application discloses an expansion device for controlling a mass flow of a refrigerant. The expansion member (20) comprises: a housing (21); a flow channel (23) and a return channel (24) formed in the housing (21); a throttle valve (25) having a spring biased throttle body (253) for narrowing a cross section of the flow channel (23); a valve control device (22) configured to control the throttle valve (25) in response to a temperature in the return passage (24), the valve control device (22) including a sealed gas filled expansion chamber thermally coupled to the return passage (24) and the throttle body (253) whose spring bias is counteracting mechanically coupled; and a temperature control device (27) thermally coupled to the valve control device (22). The application also discloses a method for controlling a mass flow of a refrigerant. The method has a temperature control of the expansion chamber of the valve control device (22) on the basis of a predetermined control strategy for changing the cross section of the flow channel (23) by means of the throttle valve (25). The application further discloses a use of an expansion element (20) in the refrigeration circuit (1) of a motor vehicle, as well as a motor vehicle with the expansion element (20).

Description

The present invention relates to an expansion device and a method for controlling or controlling a refrigerant mass flow, a use of the expansion device for a refrigeration circuit of a motor vehicle, as well as a motor vehicle with the expansion element.

STATE OF THE ART

To control the refrigerant mass flow and thus the cooling capacity of an evaporator as a function of the refrigerant temperature at the outlet of the evaporator expansion valves are used. These reduce or enlarge the flow cross-section locally and thus the pressure of the fluid flowing through.

By the pressure drop or by the expansion also decreases the temperature of the refrigerant, so that there is a temperature difference between the component to be cooled and the refrigerant. This is the basic requirement for heat transfer. The liquid refrigerant absorbs the heat from the component to be cooled and evaporates, while the temperature of the refrigerant remains constant due to the evaporation. If only gaseous refrigerant is present during sustained heat absorption, the absorbed heat can no longer be converted into a phase transition. As a result, the refrigerant heats up suddenly and overheats.

The cooling capacity and thus the maximum dissipatable heat is obtained according to the following equation (1) from the multiplication of the mass flow with the difference from the enthalpy after the evaporator h _{v_out} and the enthalpy before the expansion _element h _e or before the evaporator h _{v_in} .

As a result of friction effects occur pressure losses p _v in the evaporator, which have a negative effect on the available cooling capacity. These are proportional to the square of the flow velocity c, as expressed in equation (2) below. p _v ~ c ² (2)

Consequently, it is important to adjust the mass flow so that the required cooling capacity is available with minimal pressure loss.

Furthermore, in the event that multiple evaporators are present, the mass flow must be divided so that the above requirements that the required cooling capacity is available with minimal pressure loss, are met for each evaporator. To illustrate such a case shows 1 a schematic schematic diagram of a section of a refrigerant circuit 1 with two evaporators 10-1 . 10-2 , Every evaporator 10-1 . 10-2 is an organ of expansion 20-1 . 20-2 assigned. A total mass flow of a refrigerant feed 30 is through a distributor 35 in two branches 40-1 . 40-2 Branched with individual mass flows. Each individual mass flow m. ₁ and m. ₂ in the branches 40-1 . 40-2 becomes through the respective expansion organ 20-1 . 20-2 regulated or controlled and the respective evaporator 10-1 . 10-2 as evaporator flow 11-1 . 11-2 fed. From the respective evaporator 10-1 . 10-2 out leads the evaporator return 12-1 . 12-2 again via the expansion organ 20-1 . 20-2 and from there back to the refrigerant circuit 1 , In the illustrated cycle section, for example, the mass flows m. ₁ and m. _{2 are} adapted so that in the evaporator 10-1 the heat q. ₁ and in the evaporator 10-2 the heat q. ₂ can be dissipated.

Currently, two types of expansion devices are used as standard, namely the thermostatic expansion valve (TXV) and the electrical expansion valve (EXV).

2 shows a schematic schematic diagram of a portion of a refrigerant circuit 1 with a thermostatic expansion valve (TXV) 120 according to the prior art as an expansion organ. The TXV 120 indicates as shown in 2 a housing 21 , a head 22 , a flow channel 23 with a flow input 231 and a feed-out 232 , a return channel 24 with a return input 241 and a return outlet 242 and a throttle valve 25 on. The throttle valve 25 has a valve chamber 251 in which a spring 252 and a throttle body 253 are arranged, and a push rod 254 that with your head 22 of the expansion valve 20 and the throttle body 253 is connected. The valve room 251 also has an annular bearing surface as a valve seat for the throttle body 253 on.

The head 22 of the TXV 120 has a filled with a gas and through a membrane (not shown) limited expansion chamber (not shown), wherein the gas through the from the evaporator 10 in the cycle 1 Returning refrigerant is heated and therefore approximately the refrigerant temperature of the return 12 has. Heating causes the gas in the head to expand 22 off and pushes the push rod 254 down, which in turn on the throttle body 253 pushes, causing the spring located underneath 252 is compressed, which causes the throttle body 253 wanders down and thereby the cross section of the inlet channel 23 is increased. This increases the mass flow and thus the cooling capacity. As a result, the temperature in the evaporator 10 and thus the refrigerant temperature of the return 12 drops, allowing the gas in the head of the expansion valve 20 cools. This reduces the load on the spring 252 so that the cross section of the flow channel 23 is reduced again. By selecting the spring stiffness of the spring 252 Thus, a desired temperature window can be in the evaporator 10 establish. The temperature is dependent on the temperature of the return 12 self-sufficient regulated.

However, the spring stiffness of the thermostatic expansion valve, depending on the design of the evaporator 10 as well as the design of the cooling circuit 1 be adapted, so that a cross-project solution can hardly be realized. Experiences and experiments have also shown that the thermostatic expansion valve by the spring used 252 can begin to oscillate, so that the mass flow control is not guaranteed. Due to the autonomous structure of a diagnostic function is not given. In addition, no external control of the mass flow control can take place if a critical state has been reached.

3 shows a schematic schematic diagram of a portion of a refrigerant circuit 1 with an electric expansion valve (EXV) 121 according to the prior art as an expansion organ. The EXV 121 indicates as shown in 3 a housing 21 , a flow channel 23 and a throttle valve 25 on. The throttle valve 25 has a valve chamber 251 in which a throttle body 253 is arranged, and a servomotor 256 that with the throttle body 253 is connected. A temperature sensor 51 and a pressure sensor 52 are at the return 12 of the refrigeration circuit 1 provided and with a signaling unit 53 connected, which detection signals of the temperature sensor 51 and the pressure sensor 52 receives and to a control unit 54 signaled. The control unit 54 is signal technology with the servomotor 256 of the throttle valve 25 connected and provides this control signals on the basis of the measured state variables (p and T) of the return 12 ,

If the temperature T exceeds an upper threshold, the control unit controls 54 the servomotor 256 so on, that the servomotor 256 the throttle body 253 in the opening direction (in the figure down) moves and thus the cross section of the flow channel 23 increased. If the refrigerant temperature T of the return falls below 12 a lower threshold controls the control unit 54 the servomotor 256 so on, that the servomotor 256 the throttle body 253 in the closing direction (in the figure up) moves and thus the cross section of the flow channel 23 reduced. With the control system described can thus be a desired temperature window in the evaporator 10 establish.

4 shows a schematic schematic diagram of a portion of a refrigerant circuit 1 with another electric expansion valve (EXV) 122 according to the prior art as an expansion organ. The EXV 122 is different from the one in 3 in that there is one in the case 21 integrated return channel 24 having. The temperature sensor 51 and the pressure sensor 52 are directly in the housing 21 of the expansion valve 20 in the area of the return channel 24 appropriate. The further structure and functioning of the EXV 122 correspond with the related 3 described EXV 121 so that reference is made to avoid repetition in this regard.

Even if specific problems of the thermostatic expansion valve with the electric expansion valve can be eliminated, the use of a servomotor and the sensors significantly increases the cost compared to the thermostatic expansion valve.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an improved expansion device and method for controlling a refrigerant flow, in particular for use in a motor vehicle. In particular, an object of the present invention is to reduce the disadvantages of the thermostatic expansion valve by adapting its structure without using a servomotor.

The above object is achieved at least in part by an expansion device having the features of claim 1 and a method having the features of claim 9, a method having the features of claim 18 and a vehicle having the features of claim 19. Advantageous developments and preferred embodiments form the subject of the dependent claims. Here are features and details that are described and / or claimed in connection with the expansion device according to the invention, also in connection with the method according to the invention and in each case reversed and read alternately, so that with respect to the disclosure of the individual aspects of the invention is always reciprocal reference or can be.

The invention is based on the idea of influencing the temperature in the Expansion chamber directly on the opening or closing of the expansion valve influence.

Accordingly, a first aspect of the invention relates to an expansion device for controlling a mass flow of a refrigerant, wherein the expansion element comprises:
a housing;
a flow channel and a return channel formed in the housing;
a throttle valve with a spring biased throttle body for narrowing a cross section of the flow channel;
a valve control device configured to control the throttle valve in response to a temperature in the return passage, the valve control device having a sealed gas-filled expansion chamber thermally coupled to the return passage and mechanically coupled to the throttle body whose spring bias is counteracting; and
a tempering device, which is thermally coupled to the valve control device.

In other words, the above-described structure of the expansion device with a housing, flow and return passage, throttle valve and valve control device in the form of an expansion chamber describes a basic structure of a thermostatic expansion valve. The completed expansion chamber is preferably housed in a head of the expansion valve. The thermal coupling of the expansion chamber to the return passage causes a temperature of a gas in the expansion chamber to follow a temperature of the refrigerant in the return passage. A spring preload is understood in the context of the invention as a resilient bias in the direction of narrowing the flow channel, wherein the bias in any conceivable manner, be realized by a resilient (screw, plate spring, etc.), pneumatic, hydropneumatic or other manner generated force can. The mechanical coupling of the expansion chamber with the throttle body causes expansion of the gas in the expansion chamber, the throttle body is moved against the spring bias, whereby the cross section of the flow channel is increased. The mechanical coupling can be realized, for example, but not limited to, by means of a membrane provided in the expansion chamber or delimiting it and a pressure rod connected between the membrane and the throttle body. The throttle body may be, for example, but not limited to, a ball body, cone body or the like. Since the temperature control device is thermally coupled to the valve control device, the temperature of the expansion chamber can be increased with the attached temperature control device, so that the cross section at the inlet of the throttle valve is increased and more cooling capacity is available. A swinging of the expansion valve can be attenuated or suppressed by the design of the cross section. The need for a higher refrigeration capacity or plugging of the valve as well as the swinging of the expansion valve can be diagnosed by means of a temperature sensor at the outlet of the evaporator or on the component to be cooled.

By means of the attached tempering the temperature of the expansion chamber in the valve head and thus the cross section at the inlet of the throttle valve, d. H. in the flow channel, as well as the available cooling capacity are regulated. Due to the tempering device, the spring stiffness of the expansion device, which is designed as a thermostatic expansion valve, not be adapted for each project, since the opening of the inlet cross section can be additionally influenced by means of the temperature control device. This allows a modular solution across projects, which can reduce manufacturing costs as well as hedging and development costs. In addition, if the expansion valve begins to vibrate, the vibration can be damped by introducing heat into the valve head.

In a preferred embodiment, the tempering device may have a resistance wire heating.

In another preferred embodiment, the tempering device may comprise a PTC element, in particular a non-linear PTC heating element. The resistance of a non-linear PTC heating element, which may be, for example, but not limited to, ceramic or polymer based, is temperature dependent so that at a defined temperature (maximum allowable operating temperature), the performance of the heating element itself is reduced. This property offers high advantages in the field of operational safety.

In another preferred embodiment, the temperature control device may comprise a Peltier element. A Peltier element is an electrochemical converter that generates a temperature difference due to the so-called Peltier effect when current flows through. Depending on the current direction, the Peltier element can be used for cooling or heating. If a temperature difference is present at the Peltier element, a current flow is generated due to the Seebeck effect, so that the Peltier element can be used as a sensor. The valve head can be heated or cooled by the Peltier element so that the cross section at the inlet of the expansion valve and thus the available cooling capacity can be set as required, depending on the control strategy. Analogous to the embodiment described above with the temperature control device on the valve head, the spring stiffness does not need to be adjusted so that a cross-project planning solution can be realized and costs can be saved. The ability to reduce the cross-section of the expansion valve targeted, the mass flow can be reduced if the total cooling capacity is not needed. On the one hand, this increases the efficiency and, on the other hand, in the case of several evaporators connected in parallel, the cooling capacity can be relocated. The sensor function of the Peltier element also enables a diagnostic function. It can be detected, for example, based on the temperature measurement, whether the valve remains open despite being controlled by, for example, contamination in the valve seat. By introducing a phase-shifted vibration using the Peltier element, for example, the vibration can be eradicated.

The temperature control device can be attached to the valve control device or the expansion chamber in a force, shape or material fit manner. It would be conceivable gluing, clamping, welding or screwing of the element, which must be paid to a good thermal conductivity and a short heat conduction path between the temperature control and the expansion chamber of the valve control device.

In one embodiment variant, the tempering device can also be attached elsewhere on the housing. Preferably, the temperature control device is provided between the flow channel and the return channel, in particular between a flow outlet and a return inlet of the expansion element. On the one hand, by means of this positioning, the expansion chamber can also be indirectly tempered by the tempering device. On the other hand, the temperature control device, if it has a Peltier element, by means of this positioning convert a temperature difference between the flow and return of the refrigerant into an electric current. In other words, the Peltier element or the temperature control device with the Peltier element can also be used in this embodiment as a sensor for detecting a temperature difference between the refrigerant flow and return. The detected temperature difference can in turn be used to control the expansion organ.

As in previous embodiments, the temperature control device of this embodiment variant can be force-fit, positive-fit or material-fit in the housing. It would be conceivable gluing, clamping, welding or screwing of the element, which must be paid to a good thermal conductivity and a short heat conduction path between the temperature control and the flow and return channel.

Additional temperature sensors can be added to the diagnostics function.

The expansion devices according to the invention described here have a temperature device with an element, by means of which the cross-section at the inlet of the throttle valve and the available cooling capacity can be regulated. These expansion devices also have lower manufacturing costs than the above-mentioned electric expansion valve. Depending on the structure and positioning, a sensing of the return temperature or a temperature difference between flow and return is possible, which in turn can be controlled as an input variable for the control or regulation of the temperature.

A second aspect of the present invention relates to a method of controlling a refrigerant flow by means of an expansion device, the expansion device comprising: a housing; a flow channel and a return channel formed in the housing; a throttle valve with a spring biased throttle body for narrowing a cross section of the flow channel; and a valve control device having a sealed gas-filled expansion chamber thermally coupled to the return passage and mechanically coupled to the throttle body whose spring bias is counteracting, and the method comprises the step of:
Temperature control of the expansion chamber based on a predetermined control or control strategy for changing the cross section of the flow channel by means of the throttle valve.

As in the above-described aspect of the invention, the structure described above with a housing, supply and return passage, throttle valve and expansion chamber defines an expansion member in the form of a thermostatic expansion valve. By the inventive, controlled temperature control of the expansion chamber based on the predetermined control or control strategy for changing the cross section of the flow channel by means of the throttle valve, the cross section at the inlet of the throttle valve, for example, be increased specifically to provide more cooling capacity available. Since the method according to the invention of a controlled temperature control of the expansion chamber has the same or corresponding characteristics as the expansion element of the preceding aspect of the invention, the method achieves the same or corresponding advantages.

The tempering can be done, for example, but not only, by activating a temperature control device, which is thermally coupled to the expansion chamber. The tempering device may comprise a resistance wire heating element, a PTC element, in particular a non-linear PTC heating element, or a Peltier element.

In particular, the tempering may include heating and / or cooling.

The method may include simulating a change in a characteristic of the spring bias of the throttle valve. The method may also include defining a predetermined simulated characteristic of the spring bias based on a use case of the expansion member. The use case can be determined for example by a construction of an evaporator and the other design of the refrigerant circuit.

The method may include adjusting a cross section at the inlet of the throttle valve according to a predefined or determined cooling power requirement. The method may also include determining a need for a higher cooling capacity based on detection signals of a temperature sensor. The temperature sensor can be provided, for example, but not only, at the outlet of an evaporator or on a component to be cooled.

The method may include determining a swing of the expansion device based on detection signals of a temperature sensor. The temperature sensor can be provided, for example, but not only, at the outlet of an evaporator or on a component to be cooled. The control strategy may include a strategy for damping oscillations of the expansion device.

In a further development, the method comprises the step of detecting a temperature by means of a Peltier element used for temperature control. If a temperature difference is present at the Peltier element, a current flow is generated due to the Seebeck effect, so that the Peltier element can be used as a sensor. The sensor function of the Peltier element also allows the above-described determination of a swing of the expansion valve. For example, a strategy for damping oscillations of the expansion device may include, but not limited to, introducing a phase-shifted vibration using the Peltier element.

Additional temperature sensors can be added to the diagnostic function.

A third aspect of the present invention relates to the use of the above-described expansion element in the refrigeration circuit of a motor vehicle, in particular a car, truck or motorcycle. It is known to install expansion valves in the refrigerant circuit, in particular in the supply and return of an air conditioner. Instead of conventionally used expansion valves, the expansion device described above is used according to the invention. Since this aspect of the invention makes use of the features of the expansion element according to the invention, the same or corresponding advantages are achieved by the use.

A fourth aspect of the present invention relates to a motor vehicle, in particular a car, truck or motorcycle, with the expansion device described above, wherein the expansion element is installed in particular in the cooling circuit of the motor vehicle. Since this aspect of the invention makes use of the features of the expansion element according to the invention, the same or corresponding advantages are achieved by the vehicle with the expansion element.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features, objects and effects of the invention will become apparent from the description and the accompanying drawings.

In the drawings:

1 a schematic schematic diagram of a section of a refrigerant circuit with two evaporators;

2 a schematic schematic diagram of a refrigerant circuit section with a thermostatic expansion valve according to the prior art;

3 a schematic schematic diagram of a refrigerant circuit section with an electrical expansion valve according to the prior art;

4 a schematic diagram of a refrigerant circuit section with another electrical expansion valve according to the prior art;

5 a schematic schematic diagram of a refrigerant circuit section with a thermostatic expansion valve according to an embodiment of the present invention;

6 a schematic diagram of an RT characteristic of a heating element in the expansion valve of 5 ;

7 a schematic schematic diagram of a refrigeration circuit section with a thermostatic Expansion valve according to another embodiment of the present invention;

8th a schematic schematic diagram of a refrigerant circuit section with a thermostatic expansion valve according to another embodiment of the present invention; and

9 a schematic block diagram of a motor vehicle with a thermostatic expansion valve according to another embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A first embodiment of the present invention will now be described with reference to FIGS 5 . 6 described. It is 5 a schematic schematic diagram of a portion of a refrigerant circuit 1 with a thermostatic expansion valve 20 according to an embodiment of the present invention, and is 6 a schematic diagram of an RT characteristic of a heating element 27 in the expansion valve 20 , The thermostatic expansion valve (TXV) 20 is an expansion organ in the sense of the present invention.

The thermostatic expansion valve 20 indicates as shown in 5 a housing 21 , a head 22 , a flow channel 23 , a return channel 24 and a throttle valve 25 on. Structure and function of the thermostatic expansion valve 20 correspond to the thermostatic expansion valve 120 in the prior art (see. 2 ), so that reference can be made in this regard to the description in this regard. The head 22 or the expansion chamber with membrane, not shown, which is contained therein, can be understood as a valve control device according to the invention. It should be noted that the head 22 or the expansion chamber thermally with the return channel 24 is coupled and by means of the membrane via the push rod 254 mechanically with the throttle body 253 whose biasing direction is oppositely coupled.

In further development to the described prior art according to 2 has the thermostatic expansion valve 20 this embodiment, a heating element 27 on that at the head 22 attached and thermally coupled with this or with its expansion chamber. The heating element 27 is a tempering in the context of the present invention. The heating element 27 is a non-linear PTC heating element in this embodiment.

The resistance of a non-linear PTC heating element, which can be made for example on a ceramic or polymer basis, is temperature-dependent. In 6 is a possible curve of the RT characteristic of the heating element 27 exemplified. It turns out that from a temperature of z. B. + 20 ° C, an increased internal resistance is present. This means that at a defined temperature (for example a maximum permissible operating temperature), the power of the heating element itself is reduced. This property offers high advantages in the field of operational safety.

The heating element 27 can be force, form, or cohesive on the head 22 of the expansion valve 20 to be appropriate. It would be conceivable gluing, clamping, welding or screwing of the heating element 27 , where good thermal conductivity and a short heat conduction path between heating element 27 and head 22 must be respected. By means of the attached heating element 27 can the temperature of the head 22 of the expansion valve 20 be increased so that the cross section at the inlet of the throttle valve 25 is increased, thereby also the mass flow of the refrigerant is increased and more cooling capacity is available. Also, vibrations in the expansion valve 20 by targeted enlargement of the cross section of the flow channel 23 be dampened or suppressed.

The need for a higher cooling capacity and the swinging of the expansion valve 20 can be measured using a temperature sensor (not shown) at the outlet of the evaporator 10 or be diagnosed on the component to be cooled.

For controlling the heating element 27 For example, a control and regulation unit, which relies on detection signals from sensors, may be provided, which are not shown in greater detail for the sake of simplicity.

In an embodiment variant, not shown, the heating element 27 be a resistance wire heater.

Another embodiment of the present invention will now be described with reference to FIGS 7 described, wherein 7 a schematic schematic diagram of a portion of a refrigerant circuit 1 with a thermostatic expansion valve 20 according to the present embodiment shows. The thermostatic expansion valve (TXV) 20 is an expansion organ in the sense of the present invention.

The expansion valve 20 This embodiment is similar to the expansion valve of the previous embodiment, so that reference can be made to the relevant description with regard to the basic mode of operation. The expansion valve 20 this Embodiment has, in contrast to the previous embodiment, instead of the heating element ( 27 in 5 ) a Peltier element 28 on, on the head 22 of the expansion valve 20 is attached and therefore thermally coupled with this. The Peltier element 28 is a tempering in the context of the present invention.

The Peltier element 28 can be force, form, or cohesive on the head 22 of the expansion valve 20 to be appropriate. It would be conceivable gluing, clamping, welding or screwing of the element, with good thermal conductivity and a short heat conduction path between Peltier element 28 and head 22 must be respected.

Through the Peltier element 28 can the head 22 the expansion valve is heated or cooled and thus the cross section at the inlet of the throttle valve 25 , Thus, the mass flow of the refrigerant can be controlled or regulated and the available cooling capacity can be regulated. The sensor function of the Peltier element 28 also allows a diagnostic function if the expansion valve 20 swings. By introducing a phase-shifted vibration across the Peltier element 28 For example, the vibration can be damped or even eradicated.

By additional temperature sensors (not shown in detail), the diagnostic function can be extended.

Another embodiment of the present invention will now be described with reference to FIGS 8th described, wherein 8th a schematic schematic diagram of a portion of a refrigerant circuit 1 with a thermostatic expansion valve 20 according to the present embodiment shows. The thermostatic expansion valve (TXV) 20 is an expansion organ in the sense of the present invention.

The expansion valve 20 This embodiment is similar to the expansion valve of the previous embodiment, so that reference can be made to the relevant description with regard to the basic mode of operation. The expansion valve 20 This embodiment also has a Peltier element 29 on, but in contrast to the previous embodiment between the flow output 232 and the return input 241 on the housing 21 is appropriate. The Peltier element 29 is thermal with the flow outlet 232 and the return input 241 coupled. Further, the Peltier element 29 over the housing 21 also indirectly with the head 22 coupled. The Peltier element 29 is thus also a tempering in the context of the present invention. In addition, a temperature difference between the flow output 232 and the return input 241 determined and for controlling or regulating the temperature of the head 22 be exploited.

The Peltier element 29 can force, form, or cohesively in the housing 21 to be appropriate. Conceivable would be gluing, clamping, welding or screwing the Peltier element 29 , taking care of a good thermal conductivity as well as a short heat conduction path between Peltier element 29 and flow and return must be respected.

Another embodiment will now be described with reference to the illustration in FIG 9 described. As in 9 shown has a motor vehicle 9 a cooling circuit 1 on. The refrigeration circuit 1 has a compressor 13 , a condenser (vulgo cooler) 14 , a filter dryer 15 and an air conditioner 16 with an evaporator 10 on. In the lead 11 and return 12 of the evaporator 10 is an organ of expansion 20 incorporated, which is formed according to one of the preceding embodiments.

The invention has been described above with reference to preferred embodiments, variants, alternatives and modifications and illustrated in the figures. These descriptions and illustrations are purely schematic and do not limit the scope of the claims, but are merely illustrative of them. It is understood that the invention can be embodied and modified in many ways without departing from the scope of the claims.

It should be understood that features described in various embodiments, variations, alternatives, and modifications may also be applied in other embodiments, variations, alternatives, and modifications, and that such combinations also include embodiments, alternatives, alternatives and can form modifications of the invention. For example, it is conceivable that in addition to a heating element 27 or a first Peltier element 28 at the head 22 of the expansion valve 20 a second Peltier element 29 between flow and return of the expansion valve 20 is appropriate. Thus, an output signal of the working as a sensor Peltier element 29 as drive signal for the first Peltier element 28 or the heating element 27 be used.

As far as the preceding embodiments also describe method steps, these can, as far as they control the mass flow of the refrigerant in the refrigerant circuit 1 in various combinations are understood as independent embodiments of the present invention.

Also, the use of the expansion organ 20 according to one of the preceding embodiments in the refrigeration circuit of a motor vehicle can be understood as an embodiment of the present invention.

Further modifications, combinations, etc., which are apparent to those skilled in the art without inventive step, are fully within the scope of the appended claims.

LIST OF REFERENCE NUMBERS

1

cooling circuit

9

motor vehicle

10, 10-1, 10-2

Evaporator

11, 11-1, 11-2

Refrigerant flow to the evaporator

12, 12-1, 12-2

Refrigerant return at the evaporator

13

compressor

14

capacitor

15

dry filter

16

air conditioning

20, 20-1, 20-2

Expansion valve (expansion organ)

21

casing

22

Head (valve control device)

23

forward channel

231

Forward channel input

232

Flow channel output

24

Return channel

241

Return channel input

242

Return channel output

25

throttle valve

251

valve chamber

252

feather

253

throttle body

254

pushrod

27

heating element

28, 29

Peltier element

30

Refrigerant inlet

35

Refrigerant branch

40-1, 40-2

Refrigerant flow to the expansion valve

51

temperature sensor

52

pressure sensor

53

signaling device

54

Control and regulating device

120

Thermostatic expansion valve (prior art)

121, 122

electric expansion valve (prior art)

The above list of reference numbers and abbreviations is an integral part of the description.

Claims (19)

Expansion organ ( 20 ) for controlling a mass flow of a refrigerant, wherein the expansion element ( 20 ): - a housing ( 21 ); - a flow channel ( 23 ) and a return channel ( 24 ) in the housing ( 21 ) are formed; - a throttle valve ( 25 ) with a spring-biased throttle body ( 253 ) for narrowing a cross section of the flow channel ( 23 ); A valve control device ( 22 ) used to control the throttle valve ( 25 ) as a function of a temperature in the return channel ( 24 ), wherein the valve control device ( 22 ) a sealed gas-filled expansion chamber, which is connected to the return channel ( 24 ) is thermally coupled and with the throttle body ( 253 ) whose spring bias is counteracting mechanically coupled; and - a tempering device ( 27 ; 28 ; 29 ) connected to the valve control device ( 22 ) is thermally coupled. Expansion organ ( 20 ) according to claim 1, characterized in that the temperature control device has a resistance wire heating. Expansion organ ( 20 ) according to claim 1 or 2, characterized in that the tempering a PTC element ( 27 ), in particular a nonlinear PTC heating element. Expansion organ ( 20 ) according to one of the preceding claims, characterized in that the tempering device is a Peltier element ( 28 ; 29 ) having. Expansion organ ( 20 ) according to claim 4, characterized in that the tempering device is designed so that the Peltier element ( 28 ; 29 ) is effective for cooling and / or heating. Expansion organ ( 20 ) according to claim 4 or 5, characterized in that the tempering device is designed so that an output signal of the Peltier element ( 28 ; 29 ) is used for cooling and / or heating by means of the temperature control device. Expansion organ ( 20 ) according to one of the preceding claims, characterized in that the tempering force, positively, or cohesively on the valve control device ( 22 ), wherein the mounting in view of a good thermal conductivity and a short heat conduction path between the temperature control device and the expansion chamber of the valve control device ( 22 ) is designed. Expansion organ ( 20 ) according to one of the preceding claims, characterized in that the temperature control, force, form, or material fit between the flow channel ( 23 ) and the return channel ( 24 ), in particular between a flow output ( 232 ) and a return input ( 241 ), wherein the attachment with regard to a good thermal conductivity and a short heat conduction path between the temperature control device and the flow channel ( 23 ) and the return channel ( 24 ) is designed. Method for controlling or controlling a refrigerant flow by means of an expansion element ( 20 ), whereby the expansion organ ( 20 ) comprises: a housing ( 21 ); a flow channel ( 23 ) and a return channel ( 24 ) in the housing ( 21 ) are formed; a throttle valve ( 25 ) with a spring-biased throttle body ( 253 ) for narrowing a cross section of the flow channel ( 23 ); and a valve control device ( 22 ) with a sealed gas-filled expansion chamber connected to the return channel ( 24 ) is thermally coupled and with the throttle body ( 253 ) whose spring bias is counteracting mechanically coupled, the method comprising the step of: temperature control of the expansion chamber of the valve control device ( 22 ) based on a predetermined control strategy for changing the cross section of the flow channel ( 23 ) by means of the throttle valve ( 25 ). A method according to claim 9, characterized in that the tempering comprise heating and / or cooling. A method according to claim 9 or 10, characterized in that the tempering comprises driving a tempering device, which is thermally coupled to the expansion chamber, wherein the tempering device is preferably at least one of the a Widerstandsdrahtheizelement, a PTC element ( 27 ), in particular a nonlinear PTC heating element and a Peltier element ( 28 ; 29 Having exhibited group selected element. Method according to one of the preceding claims, further characterized by a step of simulating a change in a characteristic of the spring bias of the throttle valve ( 25 ). A method according to claim 12, further characterized by a step of defining a predetermined simulated characteristic of the spring bias based on a use case of the expansion member ( 20 ). Method according to one of the preceding claims, further characterized by a step of adjusting a cross section of the flow channel ( 23 ) according to a predefined or determined based on detection signals of a temperature sensor cooling power demand. Method according to one of the preceding claims, further characterized by a step of determining a swing of the expansion element ( 20 ) based on detection signals of a temperature sensor. Method according to one of the preceding claims, further characterized by a step of detecting a temperature by means of a Peltier element used for temperature control ( 28 ; 29 ). Method according to one of the preceding claims, characterized in that the control strategy comprises a strategy for damping oscillations of the expansion element ( 20 ), wherein the strategy for damping oscillations of the expansion organ ( 20 ) in particular introducing a phase-shifted oscillation by means of a Peltier element used for temperature control ( 28 ; 29 ) having. Use of an expansion organ ( 20 ) according to one of claims 1 to 8 in the refrigeration circuit ( 1 ) of a motor vehicle, in particular a car, truck or motorcycle. Motor vehicle, in particular a car, truck or motorcycle, with an expansion element ( 20 ) according to one of claims 1 to 8, wherein the expansion organ ( 20 ) especially in the refrigeration circuit ( 1 ) of the motor vehicle is installed.

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