DOSING APPARATUS

Abstract

A metering device for metering and supplying media via a fluid line to at least one target apparatus, in particular to an industrial textile washing machine, wherein the metering device is connected to at least one container which is filled with a medium. The metering device has a control unit which, in order to carry out a metering process with the aid of at least one pump, causes a specific volume of medium to be removed from the container and a conveyance of this volume towards the target apparatus. The fluid line has at least one heating element and at least one temperature sensor connected to a measuring device, wherein, by way of the measuring device, with the aid of a measurement value output by the temperature sensor, information about a performed conveyance of the medium through the fluid line can be determined and transmitted to the control unit.

Claims

1-40. (canceled)

41. A metering device for metering and supplying media via a fluid line to at least one target apparatus, wherein the metering device is connected to at least one container which is filled with a medium, and wherein the metering device has a control unit which, in order to carry out a metering process with at least one pump, causes a specific volume of the medium to be removed from the container and a conveyance of the volume towards the target apparatus, wherein the fluid line has at least one heating element and at least one temperature sensor connected to a measuring device, wherein the measuring device, with aid of a measurement value output by the temperature sensor, determines information about a performed conveyance of the medium through the fluid line and transmits the information to the control unit.

42. The metering device according to claim 41, wherein the measurement value is based on a measured temperature or change thereof or takes into account a measured temperature or change thereof.

43. The metering device according to claim 41, wherein the fluid line comprises a pair of temperature sensors.

44. The metering device according to claim 43, wherein the two temperature sensors are arranged symmetrically or substantially symmetrically relative to the heating element.

45. The metering device according to claim 43, wherein a first of the temperature sensors is arranged upstream of the heating element and a second of the temperature sensors is arranged downstream of the heating element.

46. The metering device according to claim 43, wherein a comparison of the values output by the two temperature sensors is carried out by the measuring device, wherein the measuring device is configured to determine from the comparison information about an effected conveyance of the medium through the fluid line and to transmit the information to the control unit.

47. The metering device according to claim 41, wherein the heating element and the temperature sensor are combined to form an assembly unit.

48. The metering device according to claim 47, wherein the assembly unit comprises an analogue output or a digital interface for a signal output.

49. The metering device according to claim 47, wherein the assembly unit has a computer unit.

50. The metering device according to claim 49, wherein the computer unit is connected to the control unit.

51. The metering device according to claim 41, wherein the heating element is arranged between the pump and the target apparatus.

52. The metering device according to claim 41, wherein the heating element is arranged upstream of the pump.

53. The metering device according to claim 41, wherein at least one heating element is assigned to the target apparatus and/or at least one heating element is assigned to the metering device.

54. The metering device according to claim 47, wherein a first assembly unit is assigned to the metering device, and at least one second assembly unit is assigned to the target apparatus.

55. The metering device according to claim 54, wherein the first assembly unit and the second assembly unit are connected to the control unit.

56. The metering device according to claim 47, wherein a plurality of target apparatuses are connected to the metering device, and each target apparatus is assigned an assembly unit.

57. The metering device according to claim 47, wherein at least one assembly unit is configured to provide a POD (proof of delivery) signal.

58. The metering device according to claim 41, wherein the heating element and the temperature sensor are an integral part of the metering device and/or are fixedly connected to the metering device.

59. A method for metering and supplying media via a fluid line to at least one target apparatus, wherein the metering device is connected to at least one container which is filled with a medium, wherein the metering device has a control unit which, in order to carry out a metering process with at least one pump, causes a specific volume of the medium to be removed from the container and the volume to be conveyed towards the target apparatus, the method comprising the steps of: a) arranging at least one heating element and at least one temperature sensor connected to a measuring device in or on the fluid line; b) conveying medium from the container to the target apparatus; c) detecting a measurement value of the temperature sensor, said value changing as a result of the conveyance of the medium, by means of measurement electronics; and d) determining by the measurement electronics, from the measurement value or taking the measurement value into account, information about a performed conveyance of the medium through the fluid line.

60. A metering device for metering and supplying media via a fluid line to at least one target apparatus, wherein the metering device is connected to at least one container which is filled with a medium, and wherein the metering device has a control unit which, in order to carry out a metering process with at least one pump, causes a specific volume of the medium to be removed from the container and a conveyance of the volume towards the target apparatus, wherein the metering device has a temperature measuring device with which a temperature of at least one medium or a temperature of an environment of the metering device is measured, wherein temperature information about the measured temperature is transmitted to the control unit, and wherein the control unit is configured to take the temperature information obtained into account when actuating the pump for carrying out a metering process or when calibrating the pump.

Description

[0164] Further advantages of the invention will become apparent from the dependent claims, not cited, and from the following description of the embodiments shown in the drawings. In the drawings:

[0165] FIG. 1 shows, in a partially sectional, block-diagram-like, schematic principle representation, a first exemplary embodiment of a metering device according to the invention with three containers connected on the input side and a target apparatus,

[0166] FIG. 2a shows, in an enlarged schematic, partially sectional view, a first exemplary embodiment of an assembly unit arranged in a fluid line of the metering device of FIG. 1, said assembly unit comprising a heating element and two temperature sensors,

[0167] FIG. 2b shows, in a representation according to FIG. 2a, a second exemplary embodiment of an assembly unit for use in a metering device according to the invention, in which the heating element is arranged on a wall opposite the wall on which the two temperature sensors are arranged,

[0168] FIG. 2c shows a further exemplary embodiment of an assembly unit to be used in a metering device according to the invention in a representation according to FIG. 2a, wherein here the heating element and the two temperature sensors are recessed in the wall of the assembly unit,

[0169] FIG. 3 shows a representation of a temporal behavior of a measurement value or a signal, which is to be understood as a differential signal of the measurement values detected by the two temperature sensors, in a first exemplary embodiment, wherein a first signal behavior is shown in solid lines and a second signal behavior of different amplitude and different time duration is shown in dashed lines,

[0170] FIG. 4 shows, for another application situation in a representation according to FIG. 3, a changed temporal signal behavior,

[0171] FIG. 5 shows, in a representation according to FIG. 3 for a changed application situation, a different temporal signal behavior,

[0172] FIG. 6 shows another exemplary embodiment of a metering device according to the invention in a representation according to FIG. 1, wherein only a single container is connected on the input side of the metering device,

[0173] FIG. 7a shows a schematic representation of a measured signal behavior in a first application situation,

[0174] FIG. 7b shows, in a representation according to FIG. 7a, a second signal behavior corresponding to a second application situation,

[0175] FIG. 7c shows, in a representation according to FIG. 7a, a third signal behavior in a third application situation,

[0176] FIG. 7d shows, in a representation according to FIG. 7a, a fourth signal behavior in a fourth application situation,

[0177] FIG. 8a shows, in a representation according to FIG. 7a, a fifth signal behavior in a fifth application situation,

[0178] FIG. 8b shows, in a representation according to FIG. 7a, a sixth signal behavior in a sixth application situation,

[0179] FIG. 8c shows, in a representation according to FIG. 7a, a seventh signal behavior in a seventh application situation,

[0180] FIG. 8d shows, in a representation according to FIG. 7a, an eighth signal behavior in an eighth application situation,

[0181] FIG. 9 shows, in a representation according to FIG. 1, a further exemplary embodiment of a metering device according to the invention, to which three target apparatus are connected on the output side, wherein a second mixture distribution device is provided, which switches the communication paths to the different target apparatus,

[0182] FIG. 10 shows another exemplary embodiment of a metering device according to the invention in a representation according to FIG. 9,

[0183] FIG. 11 shows, in a representation similar to FIG. 2a, a further exemplary embodiment of an assembly unit arranged on a metering device, with a heating element and a temperature sensor, wherein the heating element and the temperature sensor are of integrated configuration and are activated by a constant current source,

[0184] FIG. 12 shows another exemplary embodiment of an assembly unit with a heating element and two temperature sensors,

[0185] FIG. 13 shows an exemplary embodiment of a metering device according to the invention in a representation similar to FIG. 1, in which the control unit is configured to take temperature information into account when carrying out a metering process or when calibrating the pump, and

[0186] FIG. 14 shows a further exemplary embodiment of a metering device according to the invention, in which a temperature measuring device transmits temperature information about the medium to the control unit, wherein information about a performed conveyance of the medium which can be determined at the same time from the measurement values obtained from the temperature measuring device.

[0187] Exemplary embodiments of the invention are described by way of example in the following figure description, also with reference to the drawings. For the sake of clarity, like or comparable parts or elements or areas are denoted by like reference signs, sometimes with the addition of small letters—even where different exemplary embodiments are concerned.

[0188] Features described only in relation to one exemplary embodiment may also be provided in any other exemplary embodiment of the invention within the scope of the invention. Such modified exemplary embodiments—even if not shown in the drawings—are included in the invention.

[0189] All disclosed features are essential to the invention in themselves. The disclosure of the application hereby also includes the full disclosure content of the associated priority documents (copy of the prior application) as well as the cited publications and the described prior art devices, also for the purpose of including individual or several features of these documents in one or more claims of the present application.

[0190] A first exemplary embodiment of a metering device according to the invention is denoted in its entirety by 10 in FIG. 1.

[0191] Three containers 11a, 11b, 11c are connected to the metering device 10 on the input side and are each filled with a medium 12a, 12b, 12c. A suction lance 42a, 42b, 42c is immersed in each of the containers 11a, 11b, 11c and is connected to an input 20a, 20b, 20c of a mixture distribution device 17 via a supply line 54a, 54b, 54c. The mixture distribution device 17 comprises an input disc 18 and an output disc 19 rotatable about an axis of rotation 53. A motor 22 is provided to rotate the output disc 19, which acts as an actuator or actuating element 41. The motor 22 can be activated by a control unit 15 of the metering device 10 via a signal line 23b.

[0192] The mixture distribution device 17 has an output 21 to which a fluid line 13 is connected. The fluid line 13 leads to a target apparatus 14 (see for example FIG. 1). In the exemplary embodiment of FIG. 1, the target apparatus is a commercial washing machine or a household washing machine 14.

[0193] In different rotational positions of the actuator 41, a particular one of the inputs 20a, 20b, 20c is connected to the output 21, and the remaining inputs 20a, 20b, 20c are closed. In this way, the mixture distribution device 17 switches the communication paths between the containers 11a, 11b, 11c and the fluid line 13.

[0194] The washing machine 14 comprises a program selector switch 47, which is connected to a control apparatus 55 on the target apparatus 14. The control apparatus 55 of the target apparatus 14 is connected to the control unit 15 on the metering device 10 via a signal line 23a shown in dashed lines.

[0195] The metering device 10 additionally comprises a pump 16, which is also connected to the control unit 15 via a signal line 23c.

[0196] When a washing program is set by an operator at the target apparatus 14 via the program selector switch 47, the control apparatus 55 can send a request for a specific medium to the control unit 15 via the signal line 23a. In particular, the control unit 15 receives a request to deliver a predetermined amount of a predetermined medium to the target apparatus 14 at a specific time. For this purpose, the control unit 15 can first activate the motor 22 to actuate the actuating element 41 to switch the desired communication path so that the corresponding medium 12a, 12b, 12c can be conveyed. Next, the control unit 15 can activate the pump 16 to operate for a predetermined period of time or for a predetermined number of revolutions to thereby deliver a predetermined amount of medium. Subsequently, the fluid line 13 can be rinsed.

[0197] For the purpose of rinsing, the control unit can again activate the motor 22 so that the actuator 41 is shifted to another rotational position and can connect an input 20a, 20b, 20c, connected to a container with rinsing medium, to the output 21. The pump 16 can then be activated again by the control unit 15 to deliver rinsing medium.

[0198] According to the invention, in the metering device 10 according to FIG. 1, an assembly unit 30a is provided which, as shown in FIG. 2a, comprises in accordance with the invention a heating element 24 and at least one temperature sensor 25, preferably a pair 27 of temperature sensors 25a, 25b. In addition, the assembly unit 30, 30a comprises a measuring device 26.

[0199] According to FIG. 1, the assembly unit is denoted by 30a and is arranged in the flow path between the mixture distribution device 17 and the pump 16. The assembly unit 30a is therefore arranged upstream of the pump 16.

[0200] FIG. 1 additionally shows an alternative embodiment in dashed lines, according to which an assembly unit 30b with the same or identical construction can be arranged downstream of the pump 16. However, also in this alternative embodiment, the assembly unit 30b is assigned to the metering device 10. In particular, the assembly unit is part of the metering device 10.

[0201] In the following, the structural design and architecture of such an assembly unit 30, 30a, 30b will be explained with reference to the exemplary embodiment of FIG. 2a:

[0202] FIG. 2a shows a schematic diagram of an assembly unit 30 comprising a heating element 24, a first temperature sensor 25a, and a second temperature sensor 25b. The heating element 24 projects into the interior of the fluid line 13.

[0203] It should be noted that the assembly unit 30 provides a pipe section 57 which has two hose connection ends 48a, 48b for connecting corresponding portions 13a, 13b of the fluid line. For example, a circumferential rib may be provided on the pipe section 57 for this purpose. This allows the hose ends 13a, 13b to be clamped and mechanically fixed in a simple manner.

[0204] Of course, other types of fastening are also comprised by the invention.

[0205] It should be noted that, in the exemplary embodiments according to FIGS. 2a and 2b, the heating element 24 and the temperature sensors 25a, 25b partially protrude into the fluid flow; however, this geometry is only to be understood schematically.

[0206] In fact, in some exemplary embodiments, the invention will seek to arrange both the heating element and the temperature sensors flush or substantially flush with a wall of the pipe section 57, or even recessed with respect thereto, so as in any event not to interfere with the fluid flow.

[0207] On the other hand, projecting these elements 24, 25a, 25b into the fluid flow may well be desired in other exemplary embodiments, for example in order to ensure turbulence in the region of the temperature measurements and also for equalization of the fluid flow over the entire cross-section of the fluid line 13.

[0208] FIG. 2a shows that the two temperature sensors 25a, 25b are arranged symmetrically with respect to the heating element 24. The distance 29a between the temperature sensor 25a arranged upstream of the heating element 24 and the heating element 24 is the same as the distance 29b of the heating element 24 from the temperature sensor 25b arranged downstream.

[0209] The symmetrical geometry has the effect that when the medium is at a standstill, i.e. when no medium is being conveyed, the heat flow generated by the heating coil 49 or other heating apparatus is distributed evenly over the two temperature sensors 25a, 25b, so that, due to the identical distance 29a, 29b from the two sensors 25a, 25b, the same or substantially the same heat input is also measured by each of the two sensors 25a, 25b.

[0210] As soon as the pump 16 conveys medium, a medium flow indicated by the arrow P is created within the assembly unit 30. This results in the temperature sensor 25a arranged upstream no longer being able to measure any thermal energy generated by the heating element 24 due to the heat entrainment, or at least being able to measure only a considerably lower thermal energy than the temperature sensor 25b arranged downstream.

[0211] Under consideration of a differential signal, therefore no signal or almost no signal can be measured when the medium is at a standstill, and a clear signal can be measured after the pump drive has been switched on.

[0212] The exemplary embodiment of FIG. 2b has a modified symmetrical arrangement in which the heating element 24 is arranged on one wall of the assembly unit 30 and the two temperature sensors 25a, 25b are arranged on the opposite wall.

[0213] The exemplary embodiment of FIG. 2c is intended to illustrate that the temperature sensors 25a, 25b and/or also the heating element 24 can also be integrated directly into the wall of the pipe section 57 and, for example, can also arranged flush therewith.

[0214] For this purpose, the pipe section can have window-like openings in its wall area, although these are not shown in FIG. 2c.

[0215] According to FIG. 2a (—but also according to FIGS. 2b and 2c—), the assembly unit 30 comprises a heating controller 56, which ensures that the heating element 24 is activated continuously or in a clocked fashion or irregularly or, as the case may be, according to specific specifications and causes a corresponding heat input into the medium present or conveyed within the fluid line 13. The heating controller 56 is connected to a measuring device 26 via a signal line 23f. The measuring device 26 is additionally connected to the temperature sensors 25a, 25b via corresponding signal lines 23g and 23h and can receive corresponding measurement values from there.

[0216] The measuring device 26 can have a computer unit 31 or can be connected to a computer unit 31 via a signal line 23i.

[0217] The measuring device 26 is capable of signal processing or signal pre-processing the values output by or obtained from the two temperature sensors 25a, 25b.

[0218] In particular, the measuring device 26 can determine a difference between the values output by the two temperature sensors 25a, 25b. This difference value contains, in particular, information about whether medium has been conveyed through the assembly unit 30, and, in particular, also provides information about the volume of medium conveyed and the type of medium conveyed.

[0219] FIG. 3 is intended to illustrate an exemplary embodiment of a measurement in a first application situation:

[0220] The temporal course (time t) is plotted on the X-axis.

[0221] A measurement value ΔV corresponding to a result of a differential measurement is plotted on the Y-axis. This is only an example of a differential measurement value, assuming that temperature measurement values are output in volts.

[0222] This measurement value ΔV is therefore only intended as an example of an arbitrary differential measurement value.

[0223] Only the basic temporal behavior of the signal is decisive.

[0224] It is assumed that a pump 16 of a metering device 10 is switched on at a time t.sub.0. Then, differential values ΔV of zero or approximately zero are to be measured at time periods before this time t.sub.0. This is a differential measurement signal which takes into account that the same temperatures are measured at both temperature sensors 25a, 25b of the exemplary embodiment of FIG. 2a due to the symmetrical embodiment of the assembly unit 30.

[0225] Consequently, the waveform of the differential measurement value ΔV of FIG. 3 for time periods t<t.sub.0 shows a differential measurement value V.sub.0, i.e. a kind of offset value.

[0226] This can be zero or approximately zero—depending on the actual scale to be used—or in any case can be a small, substantially constant value. The value can also be subject to a certain amount of noise, as will be made clear later with the help of other actual measured values.

[0227] If, at the time to, the pump 16 is activated to deliver a predetermined amount of medium, this causes the differential signal ΔV according to FIG. 3 to rise sharply in accordance with a signal edge 51, up to a value V.sub.1. The difference between V.sub.1 and V.sub.0 is referred to as the amplitude A.sub.1.

[0228] If, at a time t=t.sub.1, the pump 16 is then switched off and thus stopped, some medium still flows. The signal ΔV corresponding to the signal falling edge 52 then drops, for example until a time t.sub.3, at which the starting value V.sub.0 is reached again.

[0229] The waveform shown in the figures is to be understood as merely schematic and illustrative.

[0230] An actually measured signal can also deviate in its signal form from the waveforms shown in the drawings.

[0231] The signal can include a statement about the amount of medium conveyed. In particular, the signal can be integrated. The area under the curve in FIG. 3 should be proportional to the flow rate, or should at least be in relation to the flow rate.

[0232] On the other hand, a statement about the duty cycle of the pump and the type of medium can be deduced from the signal form, which can be data-analyzed

[0233] In dashed lines, FIG. 3 shows a second waveform 33b, which is used for example for a different medium, for example one with a different viscosity.

[0234] However, the dashed line 33b in FIG. 3 can also represent a waveform for a conveyance of the same medium with a different pump delivery capacity.

[0235] It is assumed that the pump was switched on again at the time t=t.sub.0 for this medium as well. In this case, a changed signal rising edge 51b can be recognized in the curve of the signal 33b according to FIG. 3, either because a different medium was conveyed or because the pump provides a different delivery capacity.

[0236] When looking at FIG. 3 and the waveform of the signal 33b, it is clear that a changed maximum differential measurement value V.sub.2 is achieved, and thus a greater amplitude A.sub.2=V.sub.2−V.sub.0 is achieved than with the first medium.

[0237] Lastly, the pump is switched off at a different time, namely at the time t=t.sub.2. Another signal falling edge 52b is generated, which is denoted 52b in FIG. 3.

[0238] From these different waveforms, different signal edges 51, 51b, 52, 52b and the different amplitudes A.sub.1, A.sub.2, conclusions can be drawn about the viscosity of the conveyed medium or the type of medium. Information about the conveyed fluid volume can also be obtained from the different waveforms 33a, 33b.

[0239] FIG. 4 shows, in another application situation, a waveform 33c corresponding to FIG. 3 and a further waveform 33d, which takes into account a longer switch-on time of the pump 16 with the same medium. While in the case of waveform 33c the pump is switched off at the time t=t.sub.1, in the application situation according to waveform 33d the pump is only switched off at the time t=t.sub.2.

[0240] The flow rate can also be deduced from this signal shape. Again, by integration, i.e. by determining the area under the waveform, a statement about the conveyed volume can be obtained.

[0241] FIG. 5 again shows two different signal shapes, wherein the signal shape 33e corresponds to the signal shape 33a, and wherein a different signal shape 33f is obtained for a different medium. The signal rising edges 51, 51f and the signal falling edges 52, 52f differ significantly due to the different viscosities and the different media, possibly also due to the different heat capacities and/or the different heat conduction properties of the media used.

[0242] It remains to be noted that information can be derived on the basis of the measured waveforms of measurement values, in particular of differential measurement values, which originate from temperature sensors and can be subjected to signal processing: Thus, on the basis of signal shapes or signal contours, signal rising edges, signal falling edges, signal amplitudes, signal lengths, and signal swept areas, as well as on the basis of later periodicities or pulsations in the waveform, which are yet to be explained, a variety of information can be obtained about the conveyed volume and the type of conveyed medium.

[0243] The control unit can also relate this information to information that is already available in the control unit, for example regarding the type of medium being conveyed or the target flow rate. This allows verifications, checks and determinations of various kinds to be carried out.

[0244] FIGS. 7a to 8b show different signal patterns for different media, with different viscosities or with different heat capacities and different pump capacities. Different periodicities, different amplitudes and different signal shapes can be seen, including different waveforms, such as signal rising edges and signal falling edges.

[0245] The measurement values, in particular the measured signals, allow information to be determined. The determination of information can be carried out by the measuring device 26 or by the control unit 15 of the metering device 10. In any case, information, as far as it is determined by the measuring device 26, can be transmitted to the control unit of the metering device.

[0246] In the following, the measured waveforms of FIGS. 7a to 8d will be explained in more detail:

[0247] The schematically represented waveforms 58a, 58b, 58c, 58d, 58e, 58f, 58g, 58h of FIGS. 7a to 8d correspond to the representations which are visible on an oscilloscope when a differential measurement value is measured at an assembly unit 30, 30a, 30b, 32a, 32b, 32c.

[0248] FIGS. 7a to 7d correspond to the differential measurement values of measurements of a first medium, wherein the same pump is used in each case, but different pump delivery capacities have been set. For example, FIGS. 7a to 7d illustrate different rotational speeds or rotational rates of a peristaltic pump. Thus, FIG. 7a can be regarded as an example of a waveform 58a of a pump with a delivery capacity of only 25%, FIG. 7b for a delivery capacity of 40%, FIG. 7c for a delivery capacity of 85%, and FIG. 7d for a delivery capacity of 95%.

[0249] FIGS. 8a to 8d in turn illustrate the signal behavior for comparable different delivery capacities for a medium with a different viscosity compared to FIGS. 7a to 7d.

[0250] In any case, the following can be seen when comparing the waveforms: On the one hand, the waveforms are all or almost all periodic: The period duration is marked as T.sub.1, T.sub.2, T.sub.3, T.sub.4 etc., respectively.

[0251] The waveform of FIG. 7a has a periodicity T.sub.1. The time interval between the times t.sub.1 and to is exactly the same as the time interval between the waveform minima at the points in time t.sub.2 and t.sub.1 or t.sub.3 and t.sub.2.

[0252] It can also be seen that the period duration is shortened due to higher pump speeds—and thus is associated with a greater delivery capacity of the pump. Assuming that the time axis in FIGS. 7a to 7d is constant, the transition from FIG. 7a via FIG. 7b to FIG. 7c and to FIG. 7d shows an increasing shortening of the period duration with increasing speed of the pump 16.

[0253] The waveform with minima and maxima can be explained by the press behavior of the rolls or rollers of a peristaltic pump, which has a pair of press rollers arranged oppositely over 180°. This results in a certain pulsation 37, which is imposed on the fluid flow during operation of the peristaltic pump and which is also shown in the signal pattern of FIGS. 7a to 7d.

[0254] It should be noted that a differential measurement value is entered on the Y-axis in FIGS. 7a to 8d and is plotted in the unit of millivolts, for example. It is clear to a person skilled in the art that this can be an arbitrary variable, but one that is related to a differential measurement value and proportional thereto.

[0255] FIGS. 7a to 7d illustrate that the amplitudes can also change. In particular, FIG. 7a illustrates an amplitude A.sub.2 between minimum and maximum and FIG. 7b an amplitude A.sub.1, which is lower in comparison and which is further reduced with respect to FIG. 7c and FIG. 7d, denoted there as A.sub.1 and A.sub.2, respectively.

[0256] Lastly, the contour of the waveform also changes.

[0257] From the waveforms according to FIGS. 8a to 8d it can also be seen that both changed periodicities T.sub.5, T.sub.6, T.sub.7 and different amplitudes A.sub.3, A.sub.4, A.sub.5, A.sub.6 result at different delivery capacities of the pump for this second medium used in the measurements according to FIGS. 8a to 8d.

[0258] The metering device 10 has a memory 39 which is part of the control unit 15 or is connected thereto via a signal line 23j. Various values can be stored in the memory 39. The values can include waveforms or signal patterns or signal properties for different delivery capacities of the pumps and/or for different types of media and/or for different viscosities and/or for different delivery quantities.

[0259] The control unit 15 can determine what quantity of medium was conveyed, whether the correct quantity of medium has been conveyed, what medium has been conveyed, or whether the correct medium has been conveyed by comparison with waveforms 33a, 33b, 33c, 33d, 33e, 33f, 33g, 33h measured at the assembly unit 30 and the stored values, in particular signal patterns or waveforms.

[0260] The exemplary embodiment of FIG. 6 corresponds to the exemplary embodiment of FIG. 1, wherein only one container 11 is connected on the input side to the metering device 10 of FIG. 6.

[0261] Again, the exemplary embodiment of FIG. 6 illustrates two different positions for the assembly unit 30a, 30b, wherein these can be arranged either upstream of the pump 16 or downstream of the pump 16.

[0262] The exemplary embodiment of FIG. 9 illustrates a metering device 10 according to the invention, to which three target apparatuses 14a, 14b, 14c are connected on the output side, wherein the metering device 10 has a second mixture distribution device 43, with an input disc 44 acting as an actuating element 46 and with an output disc 45. Here, the input disc 44 can be rotationally driven by a motor 22b and can optionally establish different communication paths between the input 20 and the three outputs 21a, 21b, 21c of the output disc 45.

[0263] To avoid repetition, reference is also made to patent application EP 2 783 142 A2 with regard to this exemplary embodiment.

[0264] In the exemplary embodiment of FIG. 9, each target apparatus 14a, 14b, 14c is assigned to an assembly unit 30a, 30b, 30c. Each of the assembly units 30a, 30b, 30c is connected either to the control unit 15 of the metering device 10 and/or to a control apparatus 55 of the corresponding target apparatus 14a, 14b, 14c.

[0265] Here, the assembly unit 30a, 30b, 30c serves to provide a POD signal. This is important, for example, for certain washing or cleaning programs. It can also be used for documentation purposes in order to permanently ensure that proper metering has been performed at certain times.

[0266] FIG. 10 shows a further exemplary embodiment of a metering device according to the invention, following the exemplary embodiment of FIG. 9: Here, in addition to the assembly units 30, an additional assembly unit 32a, 32b, 32c is provided on the metering device 10 directly upstream of each of the target apparatuses 14a, 14b, 14c.

[0267] In one exemplary embodiment, assembly units 32a, 32b, 32c are configured to generate a POD (proof-of-delivery) signal. This signal can either be transmitted to the relevant control apparatus 55a, 55b, 55c of the corresponding target apparatus 14a, 14b, 14c or to the control unit 15 of the metering device 10 via the connection line shown in solid lines in FIG. 10.

[0268] In the following, a series of exemplary embodiments of methods according to the invention will be explained:

[0269] In a first exemplary embodiment, it is assumed with regard to the metering device of FIG. 1 that the assembly unit 30a measures a differential measurement value with a waveform approximately according to FIG. 7c for a predetermined period of time t after the pump 16 has been operated. From this information, the measuring device 26, possibly with the computer unit 31 connected thereto or in cooperation with the control unit 15, can determine what flow rate was pumped through the fluid line 13 by the pump 16. Such a determination can be performed, for example, by signal processing, in particular by integrating the signal according to FIG. 7c.

[0270] After determining this flow rate, this information can be used further by the control unit. For example, the delivered quantity of medium can be reported to the target apparatus or documented. It can also be compared with a request signal and the target flow rate. In this way, the control unit can check whether the metering process has been carried out properly. In the event of a discrepancy between the target flow rate and the determined or calculated flow rate, a warning signal can be emitted or a malfunction message can be triggered, for example.

[0271] In a second exemplary embodiment, a measurement signal is recorded according to FIG. 8b. The periodicity of the signal, or signal shape, or the waveform, for example the amplitudes, the signal rising edges, the signal falling edges, the signal contours, can be checked to see whether the correct medium has been conveyed by comparison with corresponding values arranged in the memory 39. These values are dependent specifically on the medium or viscosity. The control unit 15 may have previously obtained information as to which media have been connected to which inputs 20a, 20b, 20c of the metering device 10. After receiving a request signal from the target apparatus 14 and a response from the motor 22, the control unit knows which media 12a, 12b, 12c should be conveyed. By comparison with the values obtained from the assembly unit 30, 30a, 30b and with recourse to the values stored in the memory 39, it can be determined by the control unit during a verification whether the measured waveform corresponds to an expected waveform or deviates therefrom.

[0272] In the event of deviations, for example, a warning signal, a fault message or similar can be generated or initiated.

[0273] In a third embodiment, it is possible to check whether the pump 16 is still capable of conveying the target delivery quantities by measuring the waveform and determining the delivered quantity of medium on that basis. If necessary, the measured and determined flow rate values can be used to recalibrate the pump.

[0274] According to a further advantageous embodiment of the invention, it is provided that the assembly unit 30, 30a, 30b has an internal computer unit 31 with which signal processing can be performed. The signal processing can be based on the fact that values determined by the different temperature sensors 25a, 25b are subjected to a comparative consideration.

[0275] In a particular exemplary embodiment of the invention, it is provided that these considerations and calculations for optimizing the measurement results are carried out with different parameter sets. In particular, adaptations of the parameter sets to different media are provided according to the invention, wherein the media have, for example, different viscosities or different heat capacities.

[0276] Accordingly, in an exemplary embodiment of the invention, it is provided that the metering device 10, with the aid of the control unit 15, in knowledge of the medium 12a, 12b, 12c to be conveyed and in cooperation with the computer unit 31 of the assembly unit 30, 30a, 30b, transmits parameter sets or calculation parameters adapted to the medium 12a, 12b, 12c conveyed in this individual case.

[0277] Nevertheless, it is comprised by the invention if the assembly unit 30, 30a, 30b only supplies raw values and the corresponding signal processing and calculation is carried out by the control unit 15 or by a computer unit connected to the control unit 15.

[0278] FIG. 11 shows an exemplary embodiment of an assembly unit 30 of a metering device 10 according to the invention in a representation comparable to FIG. 2a, in which only a temperature sensor 25 and a heating element 24 are provided. In this exemplary embodiment, the temperature sensor 25 and the heating element 24 are integrated and combined to form an NTC component. NTC (=Negative Temperature Coefficient) components comprise a heatable resistor which exhibits a temperature-dependent resistance behavior. An NTC component is shown by way of example in the exemplary embodiment in FIG. 11, wherein it could alternatively be a PTC component.

[0279] The component 30 according to FIG. 11 comprises a constant current source 59. This supplies a constant current to the NTC component 60. The circuit, not shown, of the constant current source 59 can comprise a power limiter.

[0280] The current flowing through the component 60 heats the component or the resistor on account of ohmic heat. This causes the component 60 to reach a certain temperature.

[0281] As a measure of the electrical resistance R of the component 60, the voltage U dropping across the resistor can be measured. For this purpose, the input 61a and the output 61b of the component 60 are connected to the measuring device 26, which can carry out a voltage measurement.

[0282] When the medium 12 is stationary in the fluid line 13, the voltage to be measured is constant or almost constant. If the pump 16 responds and the medium 12 is conveyed through the fluid line 13, the medium 12 entrains thermal energy so that the temperature of the component 60 decreases. This leads—depending on whether the component 60 is an NTC element or a PTC element—to an increasing or decreasing resistance of the component 60. The change to the resistance R of the component 60 is expressed in a corresponding voltage change U. The measurement signal received by the measurement electronics 26 can thus in turn comprise information regarding the fluid conveyance through the fluid line 13.

[0283] Further exemplary embodiments, not shown, are comprised by the invention, comprising a plurality of electronic components 60 with NTC or PTC components.

[0284] The invention also comprises a situation when more than two heating elements 24 and/or more than two temperature sensors 25a, 25b are provided along the fluid line 13. For example, when using media of which the flow can easily break away when conveyed, it has proven to be advantageous if a measurement is carried out along a plurality of measurement points, i.e. along a plurality of temperature sensors that are spaced apart from each other, and a mean value formation is performed along different measurement points.

[0285] It is also comprised by the invention if a measuring circuit is used which comprises a plurality of temperature-dependent resistors as temperature sensors, which are connected in series, for example.

[0286] The exemplary embodiment of FIG. 12 shows an assembly unit 30 with a first temperature sensor 25a and with a second temperature sensor 25b.

[0287] The first temperature sensor 25a comprises a heating element 24 which is activated by a heating controller 56.

[0288] The two temperature sensors 25a, 25b can be of any configuration. For example, they can each have a temperature-dependent, measurable resistance. In the exemplary embodiment of FIG. 12, the temperature sensor 25a is connected to a first measuring device 26a via a measuring circuit and the temperature sensor 25b is connected to a measuring device 26b via an analogue measuring circuit. Both measuring devices 26a, 26b are connected to a computer unit 31 of the assembly unit 30.

[0289] The computer unit 31 is in turn connected to the heating controller 56 via a signal line 23n.

[0290] In this exemplary embodiment, it can be provided that the heating element 24 is actuated in such a way that a constant temperature difference is always measured between the two temperature sensors 25a, 25b.

[0291] For example, a first temperature T1 can be measured at the temperature sensor 25a, said first temperature differing by a constant amount, for example by 5 degrees Celsius, or by 10 degrees Celsius, or by 15 degrees Celsius from a temperature T2 measured in the region of the second temperature sensor 25b.

[0292] The heating controller 56 attempts to keep this temperature difference, which may be adjustable, constant.

[0293] The measuring devices 26a, 26b can report the measured temperature values from the two temperature sensors 25a, 25b to the computer unit 31, and the computer unit can transmit a corresponding feedback signal to the heating controller 56 via the signal lines 23. This feedback signal leads to a readjustment of the heating control and thus to a heating of the heating element 24 in order to bring the possibly out-of-balance temperature difference back to a target value.

[0294] When the medium 12 is in the fluid line 13, the heating element 24 requires a certain supplied power or energy. If the medium 12 is conveyed through the fluid line 13 by the pump 16, in order to maintain a constant temperature difference ΔT between the two temperature sensors 25a, 25b, additional heat energy must be supplied. Thus, under the premise that a heating controller 56 attempts to keep the temperature difference ΔT between the two temperature measurement values constant, the supplied heating power or heat energy for the heating element can be a measure for the conveyance of medium 12 through the fluid line 13. This value can be used as a measurement value according to the invention.

[0295] The computer unit 31 is able to compare the temperatures calculated by the measuring devices 26a, 26b and to transmit a determined signal to the heating controller 56 via the signal line 23n. The measure of this actuation can also be used as a measurement value, for example.

[0296] It is also comprised by the invention if the heating power for the heating element is determined or measured elsewhere.

[0297] The exemplary embodiment of FIG. 12 shows a control of the heating controller 56 in the manner of a digital control. Other, analogue control circuits, not shown, are also comprised by the invention.

[0298] FIG. 13 will now be used to explain an exemplary embodiment of a metering device 10 which has a temperature measuring device 62 with which a temperature of at least one medium 12a, 12b, 12c can be measured, or with which a temperature of an environment of the metering device 10 can be measured. The temperature information about the measured temperature can be transmitted to the control unit 15 of the metering device 10. The control unit 15 is configured to take the information obtained about the temperature into account when actuating the pump 16 to carry out a metering process or when calibrating the pump 16.

[0299] In the exemplary embodiment of FIG. 13, an assembly unit 30 described on the basis of the exemplary embodiments of FIGS. 1 to 12 is not provided. In the exemplary embodiment of FIG. 13, according to a first variant, a temperature measuring device 62a is provided, which is arranged directly on the fluid line 13, or projects into it, or is provided at another, suitable location. The temperature measuring device 62a is configured to measure a temperature of the medium 12a, 12b and/or a temperature of the environment of the metering device 10 and to transmit this temperature information to the control unit 15 of the metering device 10 via a signal line 230.

[0300] The metering device 10 comprises a memory 39, which is connected to the control unit 15 via the signal line 23j. Viscosity information is stored in the memory 39. This viscosity information includes, in particular, information about viscosities of different media 12a, 12b, 12c at different temperatures.

[0301] When information about the measured temperature of the medium 12a has been transmitted to the control unit 15 by the temperature measuring device 62a, the control unit 15 can determine, with recourse to the memory 39, what viscosity the medium 12a to be conveyed has at this temperature. The control unit 15 can then check whether there is cause to adjust or change the metering process, for example in such a way that a running time of the pump 16 is increased or reduced in order to supply the desired proper quantity of medium 12a, 12b, 12c to the target apparatus 14.

[0302] This procedure takes into account that media of which the viscosity increases with increasing temperature may, for example, require a longer delivery time at higher temperatures. The control unit 15 can take this circumstance into account in the sense of a longer response time of the pump 16.

[0303] FIG. 13 also shows that additional or alternative temperature measuring devices 62b, 62c, 62d, each connected via signal lines 23p, 23q, 23r, can also be connected to the control unit 15. Such an arrangement of the temperature measuring devices 62b, 62c, 62d on the containers 11a, 11b, 11c or close to the containers makes sense, for example, if the containers 11a, 11b, 11c for the media 12a, 12b, 12c are located at a distance from the metering device 10, for example in separate rooms.

[0304] The exemplary embodiment of FIG. 14 shows another example of the invention, which comprises a temperature measuring device 62 and an assembly unit described with reference to the exemplary embodiments of FIGS. 1 to 12. Here, at least one of the two temperature sensors 25a, 25b, which is arranged in the assembly unit 30a, is configured in such a way that it simultaneously provides the temperature measuring device 62. With the temperature sensors 25a, 25b, the desired information about a conveyance of medium 12 can be determined and, at the same time, temperature information about the temperature of the medium 12 can be transmitted to the control unit 15.