EP0967319A1 - Method and device for determining the laundry residual moisture in a laundry drier - Google Patents

Method and device for determining the laundry residual moisture in a laundry drier Download PDF

Info

Publication number
EP0967319A1
EP0967319A1 EP99112258A EP99112258A EP0967319A1 EP 0967319 A1 EP0967319 A1 EP 0967319A1 EP 99112258 A EP99112258 A EP 99112258A EP 99112258 A EP99112258 A EP 99112258A EP 0967319 A1 EP0967319 A1 EP 0967319A1
Authority
EP
European Patent Office
Prior art keywords
laundry
drum
residual moisture
moisture content
voltage
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP99112258A
Other languages
German (de)
French (fr)
Other versions
EP0967319B1 (en
Inventor
Wenzel Meierfrankenfeld
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Miele und Cie KG
Original Assignee
Miele und Cie KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Miele und Cie KG filed Critical Miele und Cie KG
Publication of EP0967319A1 publication Critical patent/EP0967319A1/en
Application granted granted Critical
Publication of EP0967319B1 publication Critical patent/EP0967319B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F34/00—Details of control systems for washing machines, washer-dryers or laundry dryers
    • D06F34/14—Arrangements for detecting or measuring specific parameters
    • D06F34/18—Condition of the laundry, e.g. nature or weight
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F2103/00—Parameters monitored or detected for the control of domestic laundry washing machines, washer-dryers or laundry dryers
    • D06F2103/02—Characteristics of laundry or load
    • D06F2103/08—Humidity
    • D06F2103/10—Humidity expressed as capacitance or resistance
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F2103/00—Parameters monitored or detected for the control of domestic laundry washing machines, washer-dryers or laundry dryers
    • D06F2103/44—Current or voltage
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F58/00—Domestic laundry dryers
    • D06F58/32—Control of operations performed in domestic laundry dryers 
    • D06F58/34—Control of operations performed in domestic laundry dryers  characterised by the purpose or target of the control
    • D06F58/36—Control of operational steps, e.g. for optimisation or improvement of operational steps depending on the condition of the laundry
    • D06F58/38—Control of operational steps, e.g. for optimisation or improvement of operational steps depending on the condition of the laundry of drying, e.g. to achieve the target humidity

Definitions

  • the invention relates to a method for determining the residual moisture content of the laundry in a tumble dryer with a rotatably mounted drum that receives the laundry, a heating device, a blower, a program control device and one Device for evaluating and recording the residual moisture content in the laundry by means of a capacitor, the components of which by components of the dryer such.
  • B. the Drum are formed and an apparatus for performing the method.
  • DE 196 51 883 C1 describes a method for detecting residual moisture and an arrangement known to carry out the method in which the rotatable drum and fixed door or the housing form the capacitor plates of a capacitor.
  • the Electrostatic charging is caused by the movement and mutual friction of the Laundry generated in the drum.
  • the discharge currents of this capacitor are via a connected to the fixed capacitor plate, formed by a door or housing as well as the resistance connected to the drum by sliding contact.
  • the Discharge currents are measured during specified time intervals. From the measured values of the Individual time intervals mean values are formed, the change in the mean value the Dryness of the laundry determined.
  • This embodiment has the same disadvantages as those previously known Conductivity measurement method in terms of noise generation and wear due to here Loop transformers are also used.
  • the evaluation of the intensity of the discharge current due to the electrostatic charge in the laundry at different Types of laundry such as synthetic or natural fibers are problematic.
  • Another disadvantage is that only residual moisture values below 2% can be measured with this method.
  • DE 43 21 322 A1 describes a method for the contactless determination of the Moisture content of a moving material web, in which an electric field is too high measuring path is generated. Using a high DC voltage A charge signal is influenced locally in the material web, its level and temporal behavior is recorded in charge measuring probes, which is seen in the direction of material travel downstream of the electrode and arranged in geometrically precisely defined positions are. Based on the charge build-up in the field and the subsequent unloading Residual moisture content of the material web recorded. This arrangement is suitable for the moisture content to determine a material web moving at a uniform known speed.
  • the invention thus presents the problem of a method for contactless detection of the Residual moisture content of a laundry item in a rotatably mounted laundry drum execute that the moisture values for different types of laundry and different Load quantities are recorded exactly and for the control of the drying process are to be evaluated.
  • a device for carrying out the method is said to Do not transfer the measured values by means of sliding contact in the previously usual design.
  • the device for carrying out the method is inexpensive to produce overall, because the high demands on the electrical insulation properties of contact tape pads and holder of the carbon loop transmitter are omitted.
  • the sensor electrode for Measured value acquisition is galvanically separated from the measuring arrangement and is also a pure one Alternating current is present as a measuring current, there are galvanic material migration in the Sensor electrode excluded.
  • a particular advantage of the method according to the invention is that the frequency at Input of the first capacitor can be adjusted so that over the entire Laundry resistance range a constant voltage drop across the laundry resistor can be measured is. Residual moisture values can be identified in minute increments via the frequency.
  • Drum ribs (7) are arranged in the laundry drum (1), at least one of which is formed with a measuring electrode (8) of the device for detecting the residual moisture content in the laundry.
  • This drum rib (7) is insulated from the drum jacket with the interposition of insulation (9).
  • the measuring arrangement for determining the voltage across the laundry resistance RW works contactlessly by means of a capacitor plate arrangement on the drum jacket.
  • the capacitor plates C1 and C2 of a first and second capacitor are arranged at a distance from the drum jacket.
  • the drum rib (7) which is insulated from the drum jacket, forms the second capacitor plate for both capacitors C1 and C2, which are connected to the voltage measuring device U via the washing resistor RW.
  • the ground potential M required on the drum jacket is transmitted, for example, by means of a contact spring arranged on the central bearing (10) of the drum (1). As can be seen from FIG.
  • the capacitor plates of the capacitors C1 and C2 only face each other at a certain angle of rotation of the drum (7), so that the residual moisture in the laundry can only be determined once in the course of a drum revolution.
  • the first capacitor plates of the capacitors C1 and C2, viewed in the preferred direction of rotation V of the drum (1), are arranged on a drum jacket line (11), which is measured in an angular range from 0 ° to 30 ° from the bottom dead center position of the drum rib (7).
  • the capacitor plate C1 is an AC voltage generator (12) and the capacitor plate C2 is assigned a voltage measuring device (13).
  • Figure 2 shows the circuit diagram for this arrangement.
  • the oscillator (12) generates, for example, an AC voltage of 30V with a frequency of approximately 50 Hz to 100 kHz at point a.
  • This signal is transmitted via capacitor C1 with a known capacitance to point b at the unknown laundry resistor RW.
  • the voltage that arises at point b can be calculated.
  • Ub Among other things ⁇ RW RW 2nd + XC 1 2nd
  • the voltage at point b is transmitted to the voltage measuring unit U via the capacitor C2 and measured there.
  • the laundry resistance RW can be calculated.
  • RW XC 1 2nd Among other things Ub 2nd - 1
  • the value of the residual moisture in the laundry is to be determined from the laundry resistance.
  • the residual moisture content is determined via the voltage using the method described above.
  • the frequency f is readjusted in such a way that a constant voltage drop can be measured at the laundry resistor RW.
  • RW 1 2 ⁇ f ⁇ C. 1 2nd Among other things Ub 2nd - 1

Abstract

A divider is supplied with a known alternating current and frequency of an AC generator (12). The value of the residual moisture content is determined through the voltage reduction. The dryer has condenser plates (C1,C2) of a first and a second condenser. The plates are located at a distance from the drum surface. A drum rib (7), which is insulated in respect of the drum surface, forms the second condenser plate for both condensers.

Description

Die Erfindung betrifft ein Verfahren zur Ermittlung des Restfeuchtegehaltes der Wäsche in einem Wäschetrockner mit einer die Wäsche aufnehmenden drehbar gelagerten Trommel, einer Heizungsvorrichtung, einem Gebläse, einer Programmsteuereinrichtung sowie einer Einrichtung zur Auswertung und Erfassung des Restfeuchtegehaltes in der Wäsche mittels eines Kondensators, dessen Komponenten durch Bauteile des Trockners wie z. B. die Trommel gebildet werden sowie eine Vorrichtung zur Durchführung des Verfahrens.The invention relates to a method for determining the residual moisture content of the laundry in a tumble dryer with a rotatably mounted drum that receives the laundry, a heating device, a blower, a program control device and one Device for evaluating and recording the residual moisture content in the laundry by means of a capacitor, the components of which by components of the dryer such. B. the Drum are formed and an apparatus for performing the method.

Aus der DE 196 51 883 C1 ist ein Verfahren zur Restfeuchteerfassung sowie eine Anordnung zur Durchführung des Verfahrens bekannt, bei der die drehbare Trommel und die feststehende Tür oder das Gehäuse die Kondensatorplatten eines Kondensators bilden. Die elektrostatische Aufladung wird dabei durch die Bewegung und die gegenseitige Reibung der Wäsche in der Trommel erzeugt. Die Entladeströme dieses Kondensators werden über einen mit der feststehenden Kondensatorplatte, gebildet durch Tür oder Gehäuse, verbundenen sowie mit der Trommel durch Schleifkontakt verbundenenen Widerstand gemessen. Die Entladeströme werden während festgelegter Zeitintervalle gemessen. Aus den Meßwerten der einzelnen Zeitintervalle werden Mittelwerte gebildet, wobei die Änderung des Mittelwertes den Trockengrad der Wäsche bestimmt.DE 196 51 883 C1 describes a method for detecting residual moisture and an arrangement known to carry out the method in which the rotatable drum and fixed door or the housing form the capacitor plates of a capacitor. The Electrostatic charging is caused by the movement and mutual friction of the Laundry generated in the drum. The discharge currents of this capacitor are via a connected to the fixed capacitor plate, formed by a door or housing as well as the resistance connected to the drum by sliding contact. The Discharge currents are measured during specified time intervals. From the measured values of the Individual time intervals mean values are formed, the change in the mean value the Dryness of the laundry determined.

Bei dieser Ausführung treten die gleichen Nachteile wie bei den bisher bekannten Leitfähigkeitsmeßverfahren in Bezug auf Geräuscherzeugung und Verschleiß auf, da hier ebenfalls Schleifübertrager zum Einsatz kommen. Außerdem ist die Auswertung der Intensität des Entladestromes bedingt durch die elektrostatische Aufladung in der Wäsche bei unterschiedlichen Wäschearten wie z.B Kunst- oder Naturfaser problematisch. Ein weiterer Nachteil liegt darin, daß mit diesem Verfahren nur Restfeuchtewerte kleiner als 2% meßbar sind.This embodiment has the same disadvantages as those previously known Conductivity measurement method in terms of noise generation and wear due to here Loop transformers are also used. In addition, the evaluation of the intensity of the discharge current due to the electrostatic charge in the laundry at different Types of laundry such as synthetic or natural fibers are problematic. Another disadvantage is that only residual moisture values below 2% can be measured with this method.

Die DE 43 21 322 A1 beschreibt ein Verfahren zur berührungslosen Bestimmung des Feuchtegehaltes einer bewegten Materialbahn, bei dem ein elektrisches Feld über der zu messenden Bahn erzeugt wird. Mittels einer mit hoher Gleichspannung beaufschlagten Elektrode wird lokal in der Materialbahn ein Ladungssignal influenziert, dessen Höhe und zeitliches Verhalten in Ladungsmeßsonden erfaßt wird, welche in Materiallaufrichtung gesehen der Elektrode nachgeschaltet und in geometrisch genau festgelegten Positionen angeordnet sind. Anhand des Ladungsaufbaus im Feld und der nachfolgenden Entladung wird der Restfeuchtegehalt der Materialbahn erfaßt. Diese Anordnung ist geeignet, den Feuchtegehalt einer mit gleichmäßiger bekannter Geschwindigkeit bewegten Materialbahn zu bestimmen. DE 43 21 322 A1 describes a method for the contactless determination of the Moisture content of a moving material web, in which an electric field is too high measuring path is generated. Using a high DC voltage A charge signal is influenced locally in the material web, its level and temporal behavior is recorded in charge measuring probes, which is seen in the direction of material travel downstream of the electrode and arranged in geometrically precisely defined positions are. Based on the charge build-up in the field and the subsequent unloading Residual moisture content of the material web recorded. This arrangement is suitable for the moisture content to determine a material web moving at a uniform known speed.

In einem Wäschetrockner, bei dem die Bewegung des Wäschepostens in der Trommel von der Trommeldrehzahl und Trommeldrehrichtung, der eingefüllten Wäschemenge sowie der Größe der einzelnen Wäschestücke und der Wäscheart abhängig ist, wäre eine solche Anordnung nicht einzusetzen.In a tumble dryer where the movement of the laundry item in the drum of the drum speed and direction of rotation, the amount of laundry and the Size of the individual items of laundry and the type of laundry is dependent, would be one Do not use the arrangement.

Der Erfindung stellt sich somit das Problem, ein Verfahren zur berührungslosen Erfassung des Restfeuchtegehaltes eines Wäschepostens in einer drehbar gelagerten Wäschetrommel derart auszuführen, daß die Feuchtewerte bei unterschiedlichen Wäschearten und unterschiedlichen Beladungsmengen exakt erfaßt werden und für die Steuerung des Trockenprozesses auszuwerten sind. Eine Vorrichtung zur Durchführung des Verfahrens soll auf eine Übertragung der Meßwerte mittels Schleifkontakt in der bisher üblichen Bauart verzichten.The invention thus presents the problem of a method for contactless detection of the Residual moisture content of a laundry item in a rotatably mounted laundry drum execute that the moisture values for different types of laundry and different Load quantities are recorded exactly and for the control of the drying process are to be evaluated. A device for carrying out the method is said to Do not transfer the measured values by means of sliding contact in the previously usual design.

Erfindungsgemäß wird dieses Problem durch ein Verfahren mit den im Patentanspruch 1 oder 3 angegebenen Merkmalen gelöst. Vorteilhafte Ausgestaltungen und Weiterbildungen des erfindungsgemäßen Verfahrens ergeben sich aus den jeweils nachfolgenden Unteransprüchen. Eine Vorrichtung zur Durchführung des erfindungsgemäßen Verfahrens ist in Anspruch 5 beschrieben. Vorteilhafte Ausgestaltungen und Weiterbildungen der erfindungsgemäßen Vorrichtung ergeben sich aus den nachfolgenden Unteransprüchen.According to the invention this problem is solved by a method with the in claim 1 or 3 specified features solved. Advantageous refinements and developments of the The inventive method result from the following subclaims. A device for carrying out the method according to the invention is shown in Claim 5 described. Advantageous refinements and developments of the invention Device result from the following subclaims.

Die mit der Erfindung erreichbaren Vorteile bestehen darin, daß auf die für die bisher bekannten Leitfähigkeitsmeßverfahren üblichen Kohleschleifübertrager verzichtet werden kann. Dadurch wird eine Geräuschminderung gegenüber den bekannten Leiffähigkeitsmeßverfahren und gegenüber dem aus der DE 196 51 883 C1 bekannten Stand der Technik erzielt. Außerdem ist die berührungslos arbeitende Meßanordnung verschleißfrei.The advantages that can be achieved with the invention are that for the previously Known conductivity measuring methods conventional carbon loop transmitters are dispensed with can. This results in a noise reduction compared to the known conductivity measurement methods and compared to the prior art known from DE 196 51 883 C1 achieved. In addition, the non-contact measuring arrangement is wear-free.

Die Vorrichtung zur Durchführung des Verfahrens ist insgesamt kostengünstig herstellbar, da die hohen Anforderungen an die elektrischen Isolationseigenschaften von Kontaktbandunterlagen und Halterung des Kohleschleifübertragers entfallen. Die Fühlerelektrode zur Meßwerterfassung ist galvanisch von der Meßanordnung getrennt und da außerdem ein reiner Wechselstrom als Meßstrom vorliegt, sind galvanische Materialwanderungen bei der Fühlerelektrode ausgeschlossen.The device for carrying out the method is inexpensive to produce overall, because the high demands on the electrical insulation properties of contact tape pads and holder of the carbon loop transmitter are omitted. The sensor electrode for Measured value acquisition is galvanically separated from the measuring arrangement and is also a pure one Alternating current is present as a measuring current, there are galvanic material migration in the Sensor electrode excluded.

Ein besonderer Vorteil des erfindungsgemäßen Verfahrens liegt darin, daß die Frequenz am Eingang des ersten Kondensators derart nachgeregelt werden kann, daß über den gesamten Wäschewiderstandsbereich ein konstanter Spannungsabfall am Wäschewiderstand meßbar ist. Über die Frequenz sind dadurch Restfeuchtewerte in kleinsten Abstufungen erkennbar.A particular advantage of the method according to the invention is that the frequency at Input of the first capacitor can be adjusted so that over the entire Laundry resistance range a constant voltage drop across the laundry resistor can be measured is. Residual moisture values can be identified in minute increments via the frequency.

Ein Ausführungsbeispiel der Erfindung ist in den Zeichnungen rein schematisch dargestellt und wird nachfolgend näher beschrieben. Es zeigt:

Figur 1
Einen Wäschetrockner mit einer schematischen Darstellung der Vorrichtung zur Ermittlung des Restfeuchtegehaltes in der Wäsche,
Figur 2
eine Schaltungsskizze zur Vorrichtung nach Figur 1,
Figur 3
die Anordnung der Kondensatorplatten der Vorrichtung zur Ermittlung des Restfeuchtegehaltes gegenüber dem Trommelmantel.
An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows:
Figure 1
A tumble dryer with a schematic representation of the device for determining the residual moisture content in the laundry,
Figure 2
2 shows a circuit diagram for the device according to FIG. 1,
Figure 3
the arrangement of the capacitor plates of the device for determining the residual moisture content compared to the drum shell.

In der Figur 1 ist ein Wäschetrockner mit einer die Wäsche aufnehmenden drehbar gelagerten Trommel (1), einem Gebläse (2) und einer Heizungsvorrichtung (3) in einem Prozeßluftkanal (4), einer Programmsteuereinrichtung (5) sowie einer Einrichtung (6) zur Auswertung und Erfassung des Restfeuchtegehaltes in der Wäsche dargestellt. In der Wäschetrommel (1) sind Trommelrippen (7) angeordnet, von denen mindestens eine mit einer Meßelektrode (8) der Vorrichtung zur Erfassung des Restfeuchtegehaltes in der Wäsche ausgebildet ist. Diese Trommelrippe (7) ist unter Zwischenlage einer Isolierung (9) isoliert gegenüber dem Trommelmantel angeordnet. Beim Trocknungsvorgang wird die Wäsche in der Trommel (1) bewegt und mit der warmen Prozeßluft beaufschlagt. Der Restfeuchtegehalt in der Wäsche wird über die vom Wäschewiderstand RW abhängige Spannung über den gesamten Trocknungsprozeß ermittelt. Mit zunehmender Trocknung der Wäsche nimmt der Restfeuchtegehalt ab und der Wäschewiderstand RW erhöht sich. Die Meßanordnung zur Ermittlung der Spannung über dem Wäschewiderstand RW arbeitet berührungslos mittels einer Kondensatorplattenanordnung am Trommelmantel. Dazu sind die Kondensatorplatten C1 und C2 eines ersten und zweiten Kondensators auf Abstand zum Trommelmantel angeordnet. Die isoliert gegenüber dem Trommelmantel befestigte Trommelrippe (7) bildet die zweite Kondensatorplatte für beide Kondensatoren C1 und C2, die über den Wäschewiderstand RW mit der Spannungsmeßeinrichtung U verbunden sind. Das am Trommelmantel erforderliche Massepotential M wird zum Beispiel mittels einer am Zentrallager (10) der Trommel (1) angeordneten Kontaktfeder übertragen. Wie aus der Figur 3 zu erkennen ist, stehen sich die Kondensatorplatten der Kondensatoren C1 und C2 nur in einem bestimmten Drehwinkel der Trommel (7) gegenüber, so daß die Ermittlung der Restfeuchte in der Wäsche im Verlauf einer Trommelumdrehung nur einmal erfolgen kann. Die ersten Kondensatorplatten der Kondensatoren C1 und C2 sind in Vorzugsdrehrichtung V der Trommel (1) gesehen auf einer Trommelmantellinie (11) angeordnet, die in einem Winkelbereich von 0° bis 30° gemessen von der unteren Totpunktlage der Trommelrippe (7) liegt. Der Kondensatorplatte C1 ist ein Wechselspannungserzeuger (12) und der Kondensatorplatte C2 ist eine Spannungsmeßeinrichtung (13) zugeordnet. Figur 2 zeigt die Schaltungsskizze zu dieser Anordnung. Der Oszillator (12) erzeugt beispielsweise eine Wechselspannung von 30V mit einer Frequenz von ca. 50 Hz bis 100kHz am Punkt a. Dieses Signal wird über den Kondensator C1 mit einer bekannten Kapazität auf den Punkt b am unbekannten Wäschewiderstand RW übertragen. Die am Punkt b sich einstellende Spannung läßt sich rechnerisch ermitteln. Ub = Ua · RW RW 2 + XC12 1 shows a tumble dryer with a rotatably mounted drum (1) that receives the laundry, a blower (2) and a heating device (3) in a process air duct (4), a program control device (5) and a device (6) for evaluation and detection of the residual moisture content in the laundry. Drum ribs (7) are arranged in the laundry drum (1), at least one of which is formed with a measuring electrode (8) of the device for detecting the residual moisture content in the laundry. This drum rib (7) is insulated from the drum jacket with the interposition of insulation (9). During the drying process, the laundry is moved in the drum (1) and the warm process air is applied. The residual moisture content in the laundry is determined via the voltage dependent on the laundry resistance RW over the entire drying process. As the laundry dries, the residual moisture content decreases and the laundry resistance RW increases. The measuring arrangement for determining the voltage across the laundry resistance RW works contactlessly by means of a capacitor plate arrangement on the drum jacket. For this purpose, the capacitor plates C1 and C2 of a first and second capacitor are arranged at a distance from the drum jacket. The drum rib (7), which is insulated from the drum jacket, forms the second capacitor plate for both capacitors C1 and C2, which are connected to the voltage measuring device U via the washing resistor RW. The ground potential M required on the drum jacket is transmitted, for example, by means of a contact spring arranged on the central bearing (10) of the drum (1). As can be seen from FIG. 3, the capacitor plates of the capacitors C1 and C2 only face each other at a certain angle of rotation of the drum (7), so that the residual moisture in the laundry can only be determined once in the course of a drum revolution. The first capacitor plates of the capacitors C1 and C2, viewed in the preferred direction of rotation V of the drum (1), are arranged on a drum jacket line (11), which is measured in an angular range from 0 ° to 30 ° from the bottom dead center position of the drum rib (7). The capacitor plate C1 is an AC voltage generator (12) and the capacitor plate C2 is assigned a voltage measuring device (13). Figure 2 shows the circuit diagram for this arrangement. The oscillator (12) generates, for example, an AC voltage of 30V with a frequency of approximately 50 Hz to 100 kHz at point a. This signal is transmitted via capacitor C1 with a known capacitance to point b at the unknown laundry resistor RW. The voltage that arises at point b can be calculated. Ub = Among other things · RW RW 2nd + XC 1 2nd

Die Spannung am Punkt b wird über den Kondensator C2 zur Spannungsmeßeinheit U übertragen und dort gemessen. Der Wäschewiderstand RW läßt sich rechnerisch ermitteln. RW = XC12 Ua Ub 2 - 1 The voltage at point b is transmitted to the voltage measuring unit U via the capacitor C2 and measured there. The laundry resistance RW can be calculated. RW = XC 1 2nd Among other things Ub 2nd - 1

Aus dem Wäschewiderstand ist der Wert der Restfeuchte in der Wäsche zu ermitteln.The value of the residual moisture in the laundry is to be determined from the laundry resistance.

Nach dem zuvor beschriebenen Verfahren wird der Restfeuchtegehalt über die Spannung ermittelt. In einer weiteren Ausführung ist es aber auch möglich bei gleichem Schaltungsaufbau den Wert der Restfeuchte über die Oszillatorfrequenz zu ermitteln. Dazu wird die Frequenz f derart nachgeregelt, daß am Wäschewiderstand RW ein konstanter Spannungsabfall meßbar ist. RW = 12π · f · C1 2 Ua Ub 2 - 1 The residual moisture content is determined via the voltage using the method described above. In a further embodiment, it is also possible to determine the value of the residual moisture using the oscillator frequency with the same circuit structure. For this purpose, the frequency f is readjusted in such a way that a constant voltage drop can be measured at the laundry resistor RW. RW = 1 2π f · C. 1 2nd Among other things Ub 2nd - 1

Claims (7)

Verfahren zur Ermittlung des Restfeuchtegehaltes der Wäsche in einem Wäschetrockner mit einer die Wäsche aufnehmenden drehbar gelagerten Trommel, einer Heizungsvorrichtung, einem Gebläse, einer Programmsteuereinrichtung sowie einer Einrichtung zur Auswertung und Erfassung des Restfeuchtegehaltes in der Wäsche mittels eines Kondensators, dessen Komponenten durch Bauteile des Trockners wie z. B. die Trommel gebildet werden,
dadurch gekennzeichnet, daß ein Spannungsteiler bestehend aus einer bekannten Kapazität C1 und dem zu messenden unbekannten Wäschewiderstand RW aus einem Wechselspannungsgenerator (12) mit bekannter Wechselspannung und Frequenz beaufschlagt wird und über den Spannungsabfall am Wäschewiderstand RW der Wert des Restfeuchtegehaltes ermittelt wird. Method for determining the residual moisture content of the laundry in a tumble dryer with a rotatably mounted drum that receives the laundry, a heating device, a blower, a program control device and a device for evaluating and recording the residual moisture content in the laundry by means of a capacitor, the components of which are produced by components of the dryer such as e.g. B. the drum is formed,
characterized, that a voltage divider consisting of a known capacitance C1 and the unknown laundry resistance RW to be measured is acted upon by an AC voltage generator (12) with a known AC voltage and frequency, and the value of the residual moisture content is determined via the voltage drop across the laundry resistor RW. Verfahren zur Ermittlung des Restfeuchtegehaltes der Wäsche in einem Wäschetrockner nach Anspruch 1,
dadurch gekennzeichnet, daß eine Wechselspannung von beispielsweise 30 V mit einer Frequenz im Bereich zwischen 50 Hz bis 100 kHZ erzeugt wird. Method for determining the residual moisture content of the laundry in a clothes dryer according to claim 1,
characterized, that an alternating voltage of, for example, 30 V is generated with a frequency in the range between 50 Hz to 100 kHz. Verfahren zur Ermittlung des Restfeuchtegehaltes der Wäsche in einem Wäschetrockner mit einer die Wäsche aufnehmenden drehbar gelagerten Trommel, einer Heizungsvorrichtung, einem Gebläse, einer Programmsteuereinrichtung sowie einer Einrichtung zur Auswertung und Erfassung des Restfeuchtegehaltes in der Wäsche mittels eines Kondensators, dessen Komponenten durch Bauteile des Trockners wie z. B. die Trommel gebildet werden,
dadurch gekennzeichnet, daß ein Spannungsteiler bestehend aus einer bekannten Kapazität C1 und dem zu messenden unbekannten Wäschewiderstand RW aus einem Wechselspannungsgenerator (12) mit bekannter Wechselspannung und Frequenz beaufschlagt wird, wobei die Frequenz im Verlauf des Trockenprozesses derart nachregelbar ist, daß am Wäschewiderstand RW ein konstanter Spannungsabfall über den gesamten Trockenprozeß meßbar ist und der Wert des Restfeuchtegehaltes über die durch den Wechselspannungsgenerator (12) vorgegebene Frequenz ermittelt wird. Method for determining the residual moisture content of the laundry in a tumble dryer with a rotatably mounted drum that receives the laundry, a heating device, a blower, a program control device and a device for evaluating and recording the residual moisture content in the laundry by means of a capacitor, the components of which are produced by components of the dryer such as e.g. B. the drum is formed,
characterized, that a voltage divider consisting of a known capacitance C1 and the unknown laundry resistance RW to be measured is acted upon by an AC voltage generator (12) with a known AC voltage and frequency, the frequency being readjustable in the course of the drying process in such a way that a constant voltage drop across the laundry resistor RW entire drying process is measurable and the value of the residual moisture content is determined via the frequency predetermined by the AC voltage generator (12). Verfahren zur Ermittlung des Restfeuchtegehaltes der Wäsche in einem Wäschetrockner nach Anspruch 3,
dadurch gekennzeichnet, daß die Frequenz in Bereichen derart nachregelbar ist, daß ein konstanter Spannungsabfall in einem Bereich von beispielsweise 15V bis 20V meßbar ist. Method for determining the residual moisture content of the laundry in a clothes dryer according to claim 3,
characterized, that the frequency can be adjusted in such a way that a constant voltage drop can be measured in a range of, for example, 15V to 20V. Vorrichtung zur Durchführung eines Verfahrens zur Ermittlung des Restfeuchtegehaltes der Wäsche in einem Wäschetrockner mit einer die Wäsche aufnehmenden drehbar gelagerten Trommel, einer Heizungsvorrichtung, einem Gebläse, einer Programmsteuereinrichtung sowie einer Einrichtung zur Auswertung und Erfassung des Restfeuchtegehaltes in der Wäsche mittels eines Kondensators, dessen Komponenten durch Bauteile des Trockners wie z.B. die Trommel gebildet werden,
dadurch gekennzeichnet, daß die Kondensatorplatten C1 und C2 eines ersten und zweiten Kondensators auf Abstand zum Trommelmantel angeordnet sind und die isoliert gegenüber dem Trommelmantel befestigte Trommelrippe (7) die zweite Kondensatorplatte für beide Kondensatoren bildet, die über den Wäschewiderstand RW mit der Spannungsmeßeinrichtung U verbunden sind, wobei der Kondensatorplatte C1 ein Wechselspannungserzeuger (12) zugeordnet ist und der Kondensatorplatte C2 eine Spannungsmeßeinrichtung (13) zugeordnet ist und der am Wäschewiderstand RW anliegende Spannungsabfall ein Maß für den Restfeuchtegehalt darstellt. Device for carrying out a method for determining the residual moisture content of the laundry in a tumble dryer with a rotatably mounted drum receiving the laundry, a heating device, a blower, a program control device and a device for evaluating and detecting the residual moisture content in the laundry by means of a capacitor, the components of which Components of the dryer such as the drum are formed,
characterized, that the capacitor plates C1 and C2 of a first and second capacitor are arranged at a distance from the drum shell and the drum rib (7), which is insulated from the drum shell, forms the second capacitor plate for both capacitors, which are connected to the voltage measuring device U via the laundry resistor RW, the Capacitor plate C1 is assigned an AC voltage generator (12) and capacitor plate C2 is assigned a voltage measuring device (13) and the voltage drop across the laundry resistor RW represents a measure of the residual moisture content. Vorrichtung nach Anspruch 5,
dadurch gekennzeichnet, daß die ersten Kondensatorplatten der Kondensatoren C1 und C2 in Vorzugsdrehrichtung V der Trommel (1) gesehen auf einer Trommelmantellinie (11) in einem Winkelbereich von beispielsweise 0° bis 30° gemessen von der unteren Totpunktlage der Trommelrippe (7) angeordnet sind, so daß die Restfeuchtemessung bei einer Trommelumdrehung nur jeweils einmal in der durch Anordnung der Kondensatorplatten C1 und C2 vorgegebenen Position der Trommelrippe (7) erfolgt. Device according to claim 5,
characterized, that the first capacitor plates of the capacitors C1 and C2 viewed in the preferred direction of rotation V of the drum (1) on a drum surface line (11) in an angular range of, for example, 0 ° to 30 ° from the bottom dead center position of the drum rib (7), so that the Residual moisture measurement in one drum revolution is carried out only once in the position of the drum rib (7) specified by the arrangement of the capacitor plates C1 and C2. Vorrichtung nach Anspruch 5,
dadurch gekennzeichnet, daß das am Trommelmantel erforderliche elektrische Massepotential M zur Erfassung des Spannungsabfalls am Wäschewiderstand RW über eine im Zentrallager (10) der Trommel angeordnete Kontaktfeder übertragen wird. Device according to claim 5,
characterized, that the electrical ground potential M required on the drum jacket for detecting the voltage drop across the laundry resistor RW is transmitted via a contact spring arranged in the central bearing (10) of the drum.
EP99112258A 1998-06-25 1999-06-25 Method and device for determining the laundry residual moisture in a laundry drier Expired - Lifetime EP0967319B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19828207A DE19828207A1 (en) 1998-06-25 1998-06-25 Method for determining the residual moisture content of the laundry in a tumble dryer and device for carrying out the method
DE19828207 1998-06-25

Publications (2)

Publication Number Publication Date
EP0967319A1 true EP0967319A1 (en) 1999-12-29
EP0967319B1 EP0967319B1 (en) 2003-04-23

Family

ID=7871911

Family Applications (1)

Application Number Title Priority Date Filing Date
EP99112258A Expired - Lifetime EP0967319B1 (en) 1998-06-25 1999-06-25 Method and device for determining the laundry residual moisture in a laundry drier

Country Status (3)

Country Link
EP (1) EP0967319B1 (en)
DE (2) DE19828207A1 (en)
ES (1) ES2193622T3 (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1413664A1 (en) * 2002-10-21 2004-04-28 Bonferraro S.p.A. Method and system for measuring the linen humidity in washing machines, dryers and the like
US8578627B2 (en) 2010-10-21 2013-11-12 Whirlpool Corporation Method and apparatus for moisture sensor noise immunity
EP3162952A1 (en) * 2015-10-26 2017-05-03 Electrolux Appliances Aktiebolag Laundry drying appliance with capacitive laundry drying degree sensing function
WO2019170233A1 (en) * 2018-03-07 2019-09-12 Electrolux Appliances Aktiebolag Appliance with capacitive humidity sensor
DE102018113485A1 (en) 2018-06-06 2019-12-12 Miele & Cie. Kg Dryer with residual moisture measurement system
US11193228B2 (en) 2016-12-28 2021-12-07 Electrolux Appliances Aktiebolag Laundry appliance comprising a humidity sensor
US11686041B2 (en) 2016-12-28 2023-06-27 Electrolux Appliances Aktiebolag Appliance with reliable information of a drying cycle

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19960310A1 (en) * 1999-12-14 2001-06-28 Bsh Bosch Siemens Hausgeraete Device and method for measuring the load in a laundry treatment device
DE10242144A1 (en) * 2002-09-04 2004-03-18 E.G.O. Control Systems Gmbh & Co. Kg Tumble dryer with sensor device
DE102005048890A1 (en) * 2005-10-12 2007-04-19 BSH Bosch und Siemens Hausgeräte GmbH Household laundry drier and method for detecting a rotary motion of a drum
DE102008031774B4 (en) * 2008-07-04 2010-04-15 Ident Technology Ag Sensor device for determining the amount and / or the degree of moisture of laundry in a tumble dryer
DE102008053184B4 (en) * 2008-10-24 2010-12-23 Amrhein Messtechnik Gmbh Measuring device for E-field measurement in the near field

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3765100A (en) * 1971-09-22 1973-10-16 Gen Electric Capacitive sensing dryer control
DE4321322A1 (en) 1992-07-01 1994-01-05 Pleva Gmbh Web moisture content measurement - is contactless through an electrode over material in electrical field with probes to register resistance
DE19651883C1 (en) 1996-12-13 1998-04-02 Telefunken Microelectron Tumble dryer

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2245778C2 (en) * 1972-09-15 1983-01-13 Bosch-Siemens Hausgeräte GmbH, 7000 Stuttgart Device for controlling the drying process in a tumble dryer operating on the drum principle
DE2828704C2 (en) * 1978-06-30 1982-06-09 Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt Control device for a tumble dryer
GB2102928A (en) * 1981-07-22 1983-02-09 Philips Electronic Associated Dryness sensing device for a laundry drier
DE3343179C1 (en) * 1983-11-29 1985-10-10 Bosch-Siemens Hausgeräte GmbH, 7000 Stuttgart Laundry dryer
JP2980737B2 (en) * 1991-05-24 1999-11-22 津田駒工業株式会社 Moisture control method for gluing machine

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3765100A (en) * 1971-09-22 1973-10-16 Gen Electric Capacitive sensing dryer control
DE4321322A1 (en) 1992-07-01 1994-01-05 Pleva Gmbh Web moisture content measurement - is contactless through an electrode over material in electrical field with probes to register resistance
DE19651883C1 (en) 1996-12-13 1998-04-02 Telefunken Microelectron Tumble dryer

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1413664A1 (en) * 2002-10-21 2004-04-28 Bonferraro S.p.A. Method and system for measuring the linen humidity in washing machines, dryers and the like
US8578627B2 (en) 2010-10-21 2013-11-12 Whirlpool Corporation Method and apparatus for moisture sensor noise immunity
CN108138432B (en) * 2015-10-26 2020-11-17 伊莱克斯家用电器股份公司 Laundry appliance with capacitive laundry dryness sensing function
EP3162952A1 (en) * 2015-10-26 2017-05-03 Electrolux Appliances Aktiebolag Laundry drying appliance with capacitive laundry drying degree sensing function
WO2017072016A1 (en) * 2015-10-26 2017-05-04 Electrolux Appliances Aktiebolag Laundry appliance with capacitive laundry drying degree sensing function
CN108138432A (en) * 2015-10-26 2018-06-08 伊莱克斯家用电器股份公司 Laundry appliance with condenser type cloth drying degree sensing function
US11248334B2 (en) 2015-10-26 2022-02-15 Electrolux Appliances Aktiebolag Laundry appliance with capacitive laundry drying degree sensing function
US10676859B2 (en) 2015-10-26 2020-06-09 Electrolux Appliances Aktiebolog Laundry appliance with capacitive laundry drying degree sensing function
US11193228B2 (en) 2016-12-28 2021-12-07 Electrolux Appliances Aktiebolag Laundry appliance comprising a humidity sensor
US11686041B2 (en) 2016-12-28 2023-06-27 Electrolux Appliances Aktiebolag Appliance with reliable information of a drying cycle
WO2019170233A1 (en) * 2018-03-07 2019-09-12 Electrolux Appliances Aktiebolag Appliance with capacitive humidity sensor
US11920272B2 (en) 2018-03-07 2024-03-05 Electrolux Appliances Aktiebolag Appliance with capacitive humidity sensor
DE102018113485A1 (en) 2018-06-06 2019-12-12 Miele & Cie. Kg Dryer with residual moisture measurement system

Also Published As

Publication number Publication date
ES2193622T3 (en) 2003-11-01
EP0967319B1 (en) 2003-04-23
DE59905142D1 (en) 2003-05-28
DE19828207A1 (en) 1999-12-30

Similar Documents

Publication Publication Date Title
EP0967319B1 (en) Method and device for determining the laundry residual moisture in a laundry drier
EP0767371B1 (en) Process for determining specific material characteristics
DE1928783C3 (en) Process for converting the relative movement of two bodies that are in frictional contact with one another into an electrical quantity
DE102005013441A1 (en) Sensor with capacitive measuring principle
WO2016087231A1 (en) Sensor system for a motor vehicle steering wheel, steering wheel comprising said type of sensor system and method for operating a sensor system of said type
EP2108949A1 (en) Method and device for detecting foreign matter in a moving, solid, elongated test object
EP2324275B1 (en) Contact and proximity detection using capacitive sensors
EP2097564B1 (en) Textile machine and contactless measurement process
DE102012106384A1 (en) Method for determining at least one malfunction of a conductive conductivity sensor
EP0898008B1 (en) Method for determining the loading of a laundry drier
DE19651883C1 (en) Tumble dryer
DE102008031774B4 (en) Sensor device for determining the amount and / or the degree of moisture of laundry in a tumble dryer
EP0898009A1 (en) Method for determining the loading of a laundry drier
EP0818030B1 (en) Method and devices for checking security documents
WO2008128363A1 (en) Device and method for the capacitive analysis of a moving elongate test material
EP0906985B1 (en) Method for detecting unacceptable operating conditions in an electronically controlled laundry drier
EP1108809A1 (en) Device and method for measuring the load in a washing machine
DE19839816A1 (en) Continuous monitoring of coating applied wet onto surface of dielectric e.g. nylon fiber comprises using correlated capacitative difference measurement, eliminating effects of fiber variation at high speed
DE4321322A1 (en) Web moisture content measurement - is contactless through an electrode over material in electrical field with probes to register resistance
DD237706A1 (en) METHOD FOR CONTROLLING THE DRYING PROCESS OF CARRIAGE TRACKS
DE4408312A1 (en) Non contact electrostatic yarn monitor
EP0724140B2 (en) Method and device for signal evaluation of a capacitive filling level sensor
DE2557328A1 (en) Inductive flowmeter with pulsed DC excitation - has measurement tube with electrodes buried in insulating coating of tube for liquids. of any conductivity
DE102018004188B4 (en) Laundry treatment device
DE102008031744A1 (en) Sensor device for use in dryer or washing machine, has evaluation circuit that detects electrical-field interactions using first electrode device, for determining rotational frequency of rotary object e.g. washing drum

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB IT NL SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 20000627

AKX Designation fees paid

Free format text: DE ES FR GB IT NL SE

17Q First examination report despatched

Effective date: 20020409

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): DE ES FR GB IT NL SE

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REF Corresponds to:

Ref document number: 59905142

Country of ref document: DE

Date of ref document: 20030528

Kind code of ref document: P

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: MIELE & CIE. KG

NLT2 Nl: modifications (of names), taken from the european patent patent bulletin

Owner name: MIELE & CIE. KG

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2193622

Country of ref document: ES

Kind code of ref document: T3

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20040126

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 20040617

Year of fee payment: 6

Ref country code: GB

Payment date: 20040617

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20040618

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20040622

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20040623

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20040816

Year of fee payment: 6

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050625

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050625

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050626

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050627

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060101

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060103

EUG Se: european patent has lapsed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20060228

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20050625

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 20060101

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20060228

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20050627