Circuit Arrangement and Method to Control at Least One Valve, Valve, Valve Arrangement and Seat Comfort System

Abstract

A circuit arrangement to control at least one valve includes at least one actuator with at least one positioning element adjustable between at least one first position and a second position. At least one driver unit activates the actuator and a control unit operates the driver unit. At least one air mass measuring device measures an air mass flowing through the valve. The control unit processes an output signal of the air mass measuring device. Valves, valve arrangements, seat comfort systems, and methods all use such circuit arrangements.

Claims

1. A circuit arrangement to control at least one valve including at least one actuator with at least one positioning element adjustable between at least one first position and a second position, the circuit arrangement comprising: at least one driver unit to activate the actuator and a control unit to operate the driver unit at least one air mass measuring device to measure an air mass flowing through the valve, the control unit being configured for processing an output signal of the air mass measuring device.

2. The circuit arrangement according to claim 1, the air mass measuring device includes including at least one measuring wire and one measuring device, the measuring device including at least one of: a. A resistance measuring device for measuring the a resistance of the measuring wire, b. At least one of a temperature sensor and a temperature measuring device for measuring at least one of a temperature of the measuring wire ambient temperature of the measuring wire, c. A current measuring device for measuring a heating current of the measuring wire, and d. A power measuring device for measuring an input power of the measuring wire.

3. The circuit arrangement according to claim 2, wherein at least one of the air mass measuring device the control unit is configured to determine the air mass from at least one of: a. the temperature of the measuring wire and of the heating current, b. the temperature of the measuring wire and of the input power, c. the resistance of the measuring wire and of the heating current, d. the resistance of the measuring wire and of the input power.

4. The circuit arrangement according to claim 1, wherein the actuator includes one SMA element.

5. The circuit arrangement according to claim 4, wherein the SMA element is an SMA wire, wherein the air mass measuring device includes at least one measuring wire, and wherein the SMA wire is the measuring wire or one of the measuring wires of the air mass measuring device.

6. The circuit arrangement according to claim 5, wherein the air mass measuring device includes one measuring device, and wherein the circuit arrangement is configured so that the measuring device and the driver unit are operatively connected in an alternative way to the SMA element.

7. The circuit arrangement according to claim 4, wherein the air mass measuring device includes at least one measuring wire, wherein at least a separate wire is provided in addition to the SMA element, and wherein the separate wire is the measuring wire or one of the measuring wires of the air mass measuring device.

8. The circuit arrangement according to claim 1, further including an ASIC having at least one of: the driver unit, one measuring device of the air mass measuring device and the control unit.

9. A process for controlling a valve by means of a circuit arrangement according to claim 1, the process comprising the steps of: a. Measuring an air mass, b. After the measuring step, controlling the actuator using the driver unit depending on the measured air mass, and c. Cyclically repeating the measuring and controlling steps until an end condition is reached.

10. The process according to claim 9, wherein the air mass measuring device includes at least one measuring wire, and the process additionally comprises at least one of the following steps: a. Measuring a resistance of the measuring wire, b. Measuring a temperature and an ambient temperature of the measuring wire, c. Measuring a heating current of the measuring wire, and d. Measuring an input power of the measuring wire.

11. The process according to claim 9, wherein at least two valves are assigned to the circuit arrangement and at least two actuators are provided, each actuator including one SMA element, are accordingly provided, wherein the process additionally comprises the following steps: measuring a resistance of all of the SMA elements, wherein the measuring step includes one of measuring the resistance of all of the SMA elements during a joint control downtime, or measuring the resistance of each SMA element is measured in each case between controlling one SMA element and controlling another SMA element.

12. A valve with a valve housing defining at least one first opening and one second opening, wherein the valve housing encloses one valve chamber, wherein the valve includes one actuator with one positioning element, the positioning element is configured for opening or closing the valve, and wherein the valve has one circuit arrangement for control purposes according to claim 1.

13. The valve according to claim 12, wherein one measuring wire of the air mass measuring device of the circuit arrangement is arranged in the valve chamber of the valve.

14. A valve arrangement with several valves to claim 12, wherein the circuit arrangement is integrated into a joint circuit arrangement to control each valve.

15. A seat comfort system including at least one valve according to claim 12, further including at least one air cushion, a filling level of each at least one air cushion being controllable through the at least one valve.

16. A seat comfort system including a valve arrangement according to claim 14, further including at least one air cushion, a filling level of each at least one air cushion being controllable through the at least one valve.

17. A seat comfort system including at least one circuit arrangement according to claim 1, further including at least one air cushion, a filling level of each at least one air cushion being controllable through the at least one valve.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0077] The invention will be explained in more detail below—also with regard to further characteristics and advantages—by describing the embodiments and with reference to the attached drawings, which show in each case in a schematic diagram:

[0078] FIG. 1A shows a circuit arrangement according to the state of the art,

[0079] FIG. 1B shows an SMA valve with an actuator according to the state of the art,

[0080] FIG. 10 shows an alternative design of an actuator of a valve according to the state of the art that was shown in FIG. 1B,

[0081] FIG. 2 shows a first embodiment of a circuit arrangement according to the invention,

[0082] FIG. 3 shows an embodiment of a valve according to the invention that includes an actuator with an SMA element,

[0083] FIG. 4 shows a second embodiment of a circuit arrangement according to the invention,

[0084] FIG. 5 shows a third embodiment of a circuit arrangement according to the invention,

[0085] FIG. 6 shows an example of an ASIC for a circuit arrangement according to the invention,

[0086] FIG. 7 shows an embodiment of a valve arrangement according to the invention for a seat comfort system according to the invention with several valves, and

[0087] FIG. 8 shows an embodiment of a seat comfort system according to the invention.

DETAILED DESCRIPTION

[0088] FIG. 1A, FIG. 1B and FIG. 1C show the state of the art and were already described at the beginning.

[0089] FIG. 2 shows a first embodiment of a circuit arrangement 1. The circuit arrangement 1 is designed together with several SMA elements 100-1 to 100-N, in particular SMA wires, which are shown especially as in FIG. 1B and FIG. 10, in each case as part of an actuator 103 and therefore of a valve 120, for controlling several valves 120 of a seat comfort system 2.

[0090] The circuit arrangement 1 includes one measuring device 5 and one control unit 30. The measuring device 5 can be or is connected to each one of the SMA elements 100-1 to 100-N. The measuring device 5 forms an air mass measuring device 305-1 to 305-N with every one of the SMA elements 100-1 to 100-N. The measuring device 5 can be designed as resistance measuring device, temperature measuring device, current measuring device and/or power measuring device. The SMA elements 100-1 to 100-N are connected to a voltage source U indicated by the arrow. The control unit 30 can be or is permanently connected to each one of the SMA elements 100-1 to 100-N via an SMA driver 20. The SMA drivers 20 are arranged in a driver unit 6. The measuring device 5 generates an output signal that is transmitted to the control unit 30 via a cable or wirelessly and used there as input signal for controlling or regulating the SMA drivers 20.

[0091] The measuring device 5 includes optionally one multiplexer 12 which can be or is connected to each one of the SMA elements 100-1 to 100-N, so that a resistance of one of the SMA elements 100-1 to 100-N can be especially measured by applying a measuring current by means of a power source 13. Moreover, a signal amplifier 14 is expediently provided in the measuring device 5, which can have an offset correction. The measuring signal received can now be evaluated in an evaluation unit 8 to determine the air mass. In the example shown, the evaluation unit 8 is arranged in the measuring device 5. Alternately, it can be arranged as a separate part between measuring device 5 and control unit 30.

[0092] The control unit 30 of the circuit arrangement 1 shown in FIG. 2 can be designed for activating the SMA elements 100-1 to 100-N by means of pulse width modulation.

[0093] FIG. 3 shows an alternative embodiment of a valve 120. In contrast to the valve 120 according to FIG. 1B, a wire 140 separate from the SMA element 100 is arranged in this valve 120 as measuring wire in various positions in valve 120. FIG. 3 shows exemplarily three different positions, in which the wire 140 can be arranged. For example, the wire 140 can be arranged as wire 141 in the second opening 106 and/or as wire 142 in the first opening 105 of the valve 120. Alternately or additionally, the wire 140 can be arranged in a valve chamber, such as in a flow chamber of the valve, as wire 143. In this embodiment of the valve 120 shown in FIG. 3, the wire 140 can or is also alternately or additionally connected to the measuring device 5, especially as wire 141 and/or wire 142 and/or wire 143 (see FIG. 4, for example) and form in each case an air mass measuring device together with the measuring device 5.

[0094] FIG. 4 shows a second embodiment of the circuit arrangement 1, in which in addition separate wires 140-1 to 140-M are arranged in the respective valves 120, as shown for example in FIG. 3, that just like the SMA elements 100-1 to 100-N form an air mass measuring device 305-X in each case with the measuring device 5, so that the air mass measurement can also be performed in wires 140-1 to 140-M and the control of the respective SMA element 100-1 to 100-N of the respective valve 120 takes place via the SMA driver 20 by means of this measurement. In the embodiment shown in FIG. 4, the separate wires 140-1 to 140-M are connected in parallel to the SMA elements 100-1 to 100-N, but the separate wires 140-1 to 140-M can be controlled in each case separately for performing the respective measurement. However, alternately or additionally to this control, a resistance in the SMA elements 100-1 to 100-N can also be measured, for example, by means of the circuit arrangement 1. The number M of separate wires 140-1 to 140-M and the number N of SMA elements 100-1 to 100-N can be the same or different. When alternately to an SMA element, the actuator 103 of the valve 120 controls the positioning element 104 with a piezoelectric element or a magnetic, especially electromagnetic element, this piezoelectric or magnetic element can be controlled—analogously to the SMA elements 100-1 to 100-N shown in FIG. 4—based on the respective measured values of the air mass measurement with the respective wire 140-1 to 140-M.

[0095] FIG. 5 shows a third embodiment of a circuit arrangement 1. The circuit arrangement 1 differs from the circuit arrangement 1 shown in FIG. 2 in the series resistors 21-1 to 21-N, which are in each case connected before the SMA elements 100-1 to 100-N. Optionally, as shown in FIG. 4, separate wires 140-1 to 140-M (as shown in FIG. 5) are also arranged here in addition to the SMA elements 100-1 to 100-N, before one series resistor 23-1 to 23-M is likewise connected in each case. Thus, the series resistors 21-1 to 21-N and the series resistors 23-1 to 23-M supplement in each case the respective air mass measuring device 305-X.

[0096] Furthermore, the circuit arrangement 1 according to FIG. 5 differs from the circuit arrangement 1 according to FIG. 2 in that a filter 16 is arranged in the measuring device 5 in addition to the amplifier 14. Here, several filter and amplifier levels and/or integration elements that serve to improve the signal can also be used in principle.

[0097] In the embodiment shown according to FIG. 5, the evaluation unit 8 includes a memory 36. An external memory that the evaluation unit 8 can access is also possible as an alternative or addition.

[0098] The control unit 30 includes—apart from the input 31 shown in FIG. 5, which can also be present in the other embodiments and can be executed, for example, to receive a control signal that can be transmitted wirelessly or via cable—a pulse width modulation device 60 connected to the driver unit 6 and thereby to the SMA drivers 20-1 to 20-N. Optionally, the control unit 30 can be designed for controlling the measuring device 5. As already described by means of FIG. 4, separate wires 140-1 to 140-M can also be easily integrated here into the circuit arrangement 1.

[0099] FIG. 6 shows an ASIC 4 that can be used to put into practice the circuit arrangement 1 according to the invention. This ASIC 4 can include the components of the measuring device 5, such as the evaluation unit 8 and/or the memory 36 and/or the amplifier 14 and/or the filter 16. Furthermore, the ASIC 4 can include the control unit 30 with the pulse width modulation device 60, for example. In addition, if the ASIC 4 includes the control unit 30, the ASIC especially also the input 31, designed for example to receive a control signal that can be transmitted wirelessly or via cable. Optionally, the ASIC 4 can also include the driver unit 6 with the SMA drivers 20.

[0100] FIG. 7 shows a valve arrangement 200 of a seat comfort system 2 with several valves, specifically first valves 120a and second valves 120b, controlled with a circuit arrangement 1 according to the invention. The view shows a section of an intermediate housing 208 of the seat comfort system 2. Air (indicated by dotted arrows) is supplied to a first flow area 282 assigned to the first valves 120a, in this case four valves 120a, through an air channel 276 executed from the intermediate housing 208, via a joint pressure connection 270 that can be connected to a pneumatic pump. A check valve 272 is arranged inside the air channel 276 between the pressure connection 270 and the first flow area 282. Second valves 120b, in this case four second valves 120b, are connected via a second flow area 274 to a joint opening to the atmosphere (not shown). A valve 120a and a valve 120b are in each case connected with one another through an air channel 278a, 278b, 278c, 278d on the sides fluidically opposite to the first flow area 282 or the second flow area 274 of the valves 120a, 120b.

[0101] Air cushions can be connected to the consumer connections 230a, 230b, 230c, 230d. If an air cushion is vented, the air contained therein flows in each case initially through the respective consumer connection 230a, 230b, 230c, 230d into the assigned air channel 278a, 278b, 278c, 278d and then through the assigned opened second valve 120b into the second flow area 274 and from there into the atmosphere. The corresponding first valve 120a, which is connected to the same air channel 278a, 278b, 278c, 278d, is closed in this case. When an air cushion is filled with compressed air, air from the pressure connection 270 flows into the air cushion through the first flow area 282 and the assigned opened first valve 270a and the respective air channel 278a, 278b, 278c, 278d and the respective consumer connection 230a, 230b, 230c, 230d. The corresponding second valve 120b is in this case closed.

[0102] In other words, a first valve 120a and a second valve 120b are in each case assigned to an air cushion or generally to an air cell and connected to it, whereby the first valve 120a serves to fill the air cushion with air and the second valve 120b to empty the air cushion.

[0103] In one such system shown in an unlimited way in FIG. 7, the SMA elements, especially the SMA wires of the valves 120a, 120b can firstly be used as measuring wire of the air mass measuring device and secondly separate wires 140 as measuring wire of the air mass measuring device. Regarding the separate wires 140, it is possible to arrange them in a section exclusively assigned to the respective valve 120a, 120b, as shown exemplarily in FIG. 3. Alternately or additionally, a wire 140 can also be arranged in a joint air channel 176, in FIG. 7 additionally indicated by reference character 144, and/or in the joint pressure connection 270, in FIG. 7 additionally indicated by reference character 145, and/or in the second flow area 174, in FIG. 7 additionally marked by reference character 146.

[0104] FIG. 8 shows a seat comfort system 2. In the diagram shown, the seat comfort system 2 includes a valve 120 having a first valve opening 310, a second valve opening 311, and a third valve opening 312. The first valve opening 310 is connected to a pump 300 via a fluid line 320. The second valve opening 311 is connected to an air cushion 330 via a fluid line 321. The third valve opening 312 is connected to an opening to the atmosphere 340 via an additional fluid line 322. Components of one or several air mass measuring devices, especially the measuring wires of the air mass measuring devices, can be arranged in one or several of the fluid lines 320, 321, 322. Symbolically, the air mass measuring device assigned to fluid line 320 is indicated with reference character 305a in FIG. 8, the air mass measuring device assigned to fluid line 322 with reference character 305b, and the air mass measuring device assigned to fluid line 321 with reference character 305d. Alternately or additionally, the measuring wire of an air mass measuring device can also be arranged in the valve 120 itself. In FIG. 8, this air mass measuring device is symbolically indicated with reference character 305c. In a seat comfort system 2 with several air cushions 330, the several air cushions 330 can be connected to one or several valves 120. In particular, several air cushions 330 are connected to a valve arrangement 200, whereby a valve arrangement 200 such as a valve arrangement according to FIG. 7, would essentially replace the valve 120 shown in FIG. 8, and instead the one air cushion 330 shown, several air cushions 330 would be connected in parallel to the valve arrangement 200. The air mass measuring devices, especially the measuring wires of the air mass measuring devices, can then be arranged accordingly in the valve arrangement 200 and/or in the respective air channels and/or flow areas and/or fluid lines.

LIST OF REFERENCE CHARACTERS

[0105] 1 Circuit arrangement [0106] 2 Seat comfort system [0107] 3 ASIC [0108] 4 Measuring device [0109] 5 Driver unit [0110] 8 Evaluation unit [0111] 12 Multiplexer [0112] 13 Power source [0113] 14 Signal amplifier [0114] 16 Filter [0115] 20, 20-1 to 20-N SMA driver [0116] 21-1 to 21-N Series resistor [0117] 23-1 to 23-M Series resistor [0118] 30 Control unit [0119] 31 Input [0120] 36 Memory [0121] 38 Feedback device [0122] 60 Pulse width modulation device [0123] 70 Temperature sensor [0124] 71 Voltage sensor [0125] 100, 100-1 to 100-N SMA element, e.g. SMA wire [0126] 101 Crimp [0127] 102 Valve housing [0128] 103 Actuator [0129] 104 Positioning element [0130] 104a Through-hole [0131] 105 First opening [0132] 106 Second opening [0133] 107 Limit switch [0134] 108 Sealing element [0135] 109 Valve chamber [0136] 110 Circuit board [0137] 111 Baseplate [0138] 120, 120a, 120b Valve [0139] 140, 140-1 to 140-M Wire [0140] 141 to 146 Wire [0141] 200 Valve arrangement [0142] 208 Intermediate housing [0143] 230a to 230d Consumer connection [0144] 270 Pressure connection [0145] 272 Check valve [0146] 274 Second flow area [0147] 276 Air channel [0148] 278a to 278d Air channel [0149] 282 First flow area [0150] 300 Pump [0151] 305-1 to 205-N, 305-X Air mass measuring device [0152] 305a to 305d Air mass measuring device [0153] 310 First valve opening [0154] 311 Second valve opening [0155] 312 Third valve opening [0156] 320 Fluid line [0157] 321 Fluid line [0158] 322 Fluid line [0159] 330 Air cushion [0160] 340 Opening to the atmosphere [0161] U Voltage source