EP2162580B1

EP2162580B1 - A washer/dryer

Info

Publication number: EP2162580B1
Application number: EP08760478A
Authority: EP
Inventors: Hakan Ozkahraman; Namik Yilmaz; Bulent Efecik
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2007-06-05
Filing date: 2008-06-04
Publication date: 2010-07-28
Anticipated expiration: 2028-06-04
Also published as: ES2348274T3; ATE475739T1; EP2162580A2; WO2008148788A2; WO2008148788A3; DE602008001988D1

Abstract

The present invention relates to a washer/dryer (1) wherein user safety is maintained by ensuring that the electric motor (2) rotating the drum is halted when the door is opened or an opening command is transmitted. The washer/dryer (1) comprises a microprocessor (6) that allows the door lock (4) to be opened only after ensuring that the electric motor (2) has halted before the door is opened, and an extra control circuit (7) that cuts off the energy of the relay (3) operating the electric motor (2) in the case the microprocessor (6) is in error.

Description

The present invention relates to a washer/dryer wherein the drum is not rotated when the door is opened.
The doors of washer/dryers, for example of the washing machines, are automatically locked during the washing process for the safety of the user. When the rotation of the drum containing the laundry stops after the washing process, the door is allowed to be opened by the user. In known implementations, various types of door safety circuits are used that permit the door lock to be opened or closed and the operation of the circuits are controlled by an electronic control system. A microprocessor is provided in the electronic control system, and the open -closed status of the door and the operation of the motor rotating the drum are controlled by a software in the microprocessor. Some problems arise due to the electronic control systems being software based like the microprocessor. The microprocessors can be affected by noise, irregularity in the mains voltage or the electromagnetic field in the air and unexpected errors may occur. Some defects, such as "bugs" in the software can cause the safety algorithm not to function properly and the machine to change to the error mode.
In documents EP-A1-0 702 103 and GB-A-1167720 , a safety circuit is disclosed that keeps the washing machine door locked while the drum of the washing machine is rotating. The voltage generated in the tacho-generator at the washing or spinning speeds of the washing machine drum is converted to an electric signal whereby the switching device that energizes the door lock is controlled.
The aim of the present invention is the realization of a washer/dryer wherein user safety is provided by stopping the rotation of the drum when an error is detected in the circuit energizing the door lock.
The washer/dryer realized in order to attain the aim of the present invention is explicated in the claims.
The washer/dryer comprises a relay that operates, halts or changes the operating direction of the motor that rotates the drum, a door lock that is locked up during washing preventing the opening of the door and allows the door to be opened at the end of the washing process, a triac that energizes the door lock and a micro processor that regulates the functioning of the electric motor and the door lock. In the washer/dryer of the present invention, when the door opens as a result of an error in the microprocessor, if the motor cannot be halted, the control circuit guarantees that the electric motor is halted.
One end of the control circuit is connected to the line between the triac and the door lock, and the other end to the relay of the electric motor and the control circuit measures the voltage on the triac or the door lock by taking the mains voltage as reference. The control circuit decides whether or not the triac is in error depending on the measured voltage and if the triac is decided to be in error, then cuts off the feed current of the relay and halts the electric motor.
In an embodiment of the present invention, if the control circuit detects a low voltage on the triac by detecting the voltage difference between the neutral line (0 Volt) of the mains voltage and the triac outlet, decides that the triac is in transmission and delivers energy to the relay. When the control circuit detects a voltage close to the mains voltage on the triac, decides that the triac is open circuit, that is in error, and cuts off the energy that feeds the relay.
In another embodiment of the present invention, the control circuit detects the voltage difference between the door lock inlet and the door lock outlet in the phase side (220 - 230 V) of the mains voltage, and if a voltage is detected on the door lock, decides that the triac is in transmission and delivers energy to the relay. When the control circuit does not detect a voltage on the door lock, decides that a triac error is causing the door lock not to be driven and cuts off the energy that feeds the relay.
The washer/dryer realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
Figure 1 - is the schematic view of a control circuit in a washer/dryer.
The elements illustrated in the figures are numbered as follows:

1. Washer/dryer
2. Electric motor
3. Relay
4. Door lock
5. Triac
6. Microprocessor
7. Control circuit
8. Voltage divider
9. Rectifier
10. Opto-isolator

The washer/dryer (1) comprises an electric motor (2) that moves the drum wherein the laundry is emplaced, one or more relays (3) that changes to the active - passive mode by being energized with the control signals received and maintains the electric motor (2) to be operated, halted or the operational direction changed, a door for accessing the drum, a door lock (4), for example the electromagnetic type, that prevents the door to be opened by being locked during the washing and allows the door to be opened after the washing process, a triac (5) connected to the main power supply that energizes the door lock (4) by functioning as a switching device and a microprocessor (6) that regulates the operation of the electric motor (2) and the door lock (4) for maintaining user safety, for example before the door is opened by the user after the washing process, gives the command for opening the door lock (4) after the completion of inertial rotation of the electric motor (2).
The washer/dryer (1) of the present invention comprises a control circuit (7),

comprising a first end (T1) that is connected to the line between the triac (5) and the door lock (4), and a second end (T2) connected to the relay (3),
that measures the voltages on the triac (5) or the door lock (4) by taking the mains voltage as reference,
that decides whether or not the triac (5) is open circuit (faulty) depending on the measured voltage value, and
if the triac (5) is decided to be in error, cuts off the feed current of the relay (3) for halting the electric motor (2).

If the control circuit (7), decides that the triac (5) is in transmission (normal) after evaluating the voltage measured on the triac (5) or the door lock (4), then the operation control of the relay (3) is maintained by the microprocessor (6) and the control circuit (7) does not interfere in the operation of the microprocessor (6).
When the control circuit (7) detects that the triac (5) is open circuit and not functioning, cuts off the energy feeding the relay (3) maintaining thereof to change to passive mode and halts the electric motor (2) without taking notice of the microprocessor (6) commands.
In the washer/dryer (1), the triac (5) is controlled by the microprocessor (6) under normal work conditions and the control circuit (7) is activated when the triac (5) does not operate as a result of a microprocessor (6) error, providing an additional security.
The control circuit (7) comprises a voltage divider (8) that measures and evaluates the voltage on the triac (5) or the door lock (4), a rectifier (9) that converts AC voltage to DC voltage and furthermore transistors are provided in the control circuit (7) that function as switches for delivering energy to the relay (3) or cut off the energy to the relay (3) as a result of evaluating the measured voltage.
In an embodiment of the present invention, the control circuit (7) detects the voltage difference between the triac (5) inlet and triac (5) outlet on the side of the mains voltage (L1), for example when a low voltage like 1 - 2 V close to the voltage generated by the triac (5) is detected, decides that the triac (5) is in transmission (not in error) and delivers energy to the relay (3) , and if a voltage like the 220 - 230 V close to the mains voltage is detected on the triac (5), then cuts off the energy feeding the relay (3) by deciding that the triac (5) is in error.
The transistors are selected such that energy is delivered to the relay (3) when a low voltage that has to be generated at the triac (5) is detected, and to cut off the energy delivered to the relay (3) when a voltage close to mains voltage is measured. In the condition that the triac (5) functions normally, the voltage difference between the triac (5) outlet and the neutral line (zero voltage) of the mains voltage is reduced by means of the voltage divider (8) and is converted to DC voltage by means of the rectifier (9). The DC voltage is then delivered to the relay (3) by means of the transistors.
In the condition that the triac (5) is in error (open circuit), an approximate mains voltage is detected on the triac (5), the mains voltage is transmitted to the transistors through the voltage divider (8) and the rectifier (9), the DC voltage causes the transistors to interrupt transmission and energy is not delivered to the relay (3) from the transistors.
In another embodiment of the present invention, the control circuit (7) detects the voltage difference between the door lock (4) inlet and door lock (4) outlet in the phase side (220 - 230 V) (L2) of the mains voltage, and if a voltage is detected on the door lock (4), decides that the triac (5) is in transmission and delivers energy to the relay (3). When the control circuit (7) does not detect a voltage on the door lock (4), then decides that a triac (5) error is causing the door lock (4) not to be energized and cuts off the energy that feeds the relay (3).
In this embodiment, the control circuit (7) comprises an opto-isolator (10) that transmits the voltage in suitable values since the reference of the door lock (4) is the phase line (L2) of the mains voltage having 220 - 230 V voltage and the reference of the control circuit (7) is the neutral line (0 Volt) (L1) of the mains voltage. When the triac (5) is activated and the transistors are transmitting energy to the relay (3), the opto-isolator (10) is in the passive mode. When the triac (5) is open circuit (in error), the opto-isolator (10) is in the active mode since mains voltage is measured on the triac (5) and by the voltage it delivers, maintains the transistors to cut off the energy transmitted to the relay (3).
The control circuit (7) of the present invention is activated when the microprocessor (6) controlling operation of the door lock (4) and the electric motor (2) is in error thereby maintaining to halt the electric motor (2) when the door of the washer/dryer (1) is opened.

Claims

A washer/dryer (1) comprising electric motor (2) that moves the drum wherein the laundry is emplaced, one or more relays (3) that changes to the active - passive mode by being energized with the control signals received and maintains the electric motor (2) to be operated, halted or the operational direction changed, a door lock (4) that prevents the door to be opened during the washing by being locked and allows the door to be opened after the washing process, a triac (5) that energizes the door lock (4) by functioning as a switching device and a microprocessor (6) that regulates the operation of the electric motor (2) and the door lock (4), and characterized by a control circuit (7) - comprising a first end (T1) that is connected to the line between the triac (5) and the door lock (4), and a second end (T2) connected to the relay (3), - that measures the voltages on the triac (5) or the door lock (4) by taking the mains voltage as reference, - that decides whether or not the triac (5) is in error depending on the measured voltage value, and - if the triac (5) is decided to be in error, cuts off the feed current of the relay (3) for halting the electric motor (2).
A washer/dryer (1) as in Claim 1, characterized by the control circuit (7) comprising a voltage divider (8) that measures and evaluates the voltage on the triac (5) or the door lock (4), and a rectifier (9) that converts AC voltage to DC voltage.
A washer/dryer (1) as in Claim 1 or 2, characterized by the control circuit (7) that detects the voltage difference between the triac (5) inlet and triac (5) outlet on the side of the mains voltage (L1), and if a low voltage on the triac (5) is detected, decides that the triac (5) is in transmission and delivers energy to the relay (3) , and if a voltage close to the mains voltage is detected on the triac (5), then cuts off the energy feeding the relay (3) by deciding that the triac (5) is in error.
A washer/dryer (1) as in Claim 1 or 2, characterized by the control circuit (7) that detects the voltage difference between the door lock (4) inlet and door lock (4) outlet on the side of the mains voltage (L2), and if a voltage is detected on the door lock (4), decides that the triac (5) is in transmission and delivers energy to the relay (3) but if a voltage is not detected on the door lock (4), then decides that a triac (5) error is causing the door lock (4) not to be energized and cuts off the energy that feeds the relay (3).
A washer/dryer (1) as in Claim 4, characterized by the control circuit (7) comprising an opto-isolator (10).