KR100314180B1 - Safety device operated at opening door in washing machine - Google Patents

Abstract

The present invention relates to a door opening safety device of a washing machine, and when the door is opened, a power cutoff signal and a door opening signal are output from the door opening detecting unit, and another power source is supplied from the control unit by the door opening signal output from the door opening detecting unit. A cut-off signal is output and the power cut-off unit is operated by a power cut-off signal applied from at least one of the door open detection unit and the control unit to cut off the power applied to the washing motor.

Therefore, when the door is opened, the power cutoff unit may be operated by the power cutoff signal output from the door open detection unit even if the power cutoff signal is not output from the controller due to a failure of the controller.

Description

Door opening safety device of washing machine {SAFETY DEVICE OPERATED AT OPENING DOOR IN WASHING MACHINE}

The present invention relates to a door opening safety device for a washing machine, and more particularly, to a door opening safety device for a washing machine capable of preventing an accident in which the washing motor is driven even when the door is opened due to a failure of the control unit.

In general, as shown in FIG. 1, the washing machine includes a door 3 hinged at one end of the main body 1 to open and close freely, and prevents vibrations during washing and dehydration in the main body 1. Laundry including a barrel (5) which is suspended at a predetermined height through a plurality of tension bars (not shown) and stores washing water, and an inner barrel (7) which is located inside the barrel (5) for washing and dewatering laundry. A cumulative dewatering tank 8 is provided.

In the inner cylinder 7 of the washing and dewatering tank 8, a pulsator 9 for forming a water flow in the washing water by left and right stirring is provided, and the outer cylinder 5 of the washing and dehydrating tank 8 is provided. ) On the bottom, a washing motor 11 is installed to generate rotational force by receiving a commercial AC voltage from the outside through a power cable, not shown, and on one side of the washing motor 11, the rotational force of the washing motor 11 is provided. Is transmitted through the belt 13, the power transmitter 15 is installed to rotate the inner cylinder (7) of the pulsator (9) or the washing and dehydration tank (8).

In addition, the upper part of the main body 1 is provided with a water supply means 17 including a water supply pipe and a water supply valve 18 so as to supply the wash water into the washing and dehydration tank (8). One side of the (17) is provided with a detergent dissolvers 19 for dissolving powder detergent in the wash water supplied through the water supply means 17 and at the same time supplying a softening agent to prevent static electricity and to give flexibility to the laundry. On the lower surface of the washing and dewatering tank 8, a drain valve 21 is installed to drain the washing water in the washing and dewatering tank 8 through the drain hose 23 during washing, rinsing and dehydration.

On the other hand, the drive control device for a washing machine for driving a washing machine configured as described above is installed on a predetermined portion of the upper surface of the main body 1 in contact with the inner surface of the door 3, as shown in FIG. 3) On / off according to the opening and closing of the door switch 31 for outputting the door opening and closing signal, the resistance 32 for surge absorption and the key input unit 33 for inputting the washing conditions and the operating state of the washing machine The control unit 35 and the control unit 35 outputting control signals for controlling the respective units of the washing machine by the door open / close signal from the driving display unit 34 and the door switch 31 and the key signal from the key input unit 33. A control transistor 36 that is turned on or off by a control signal from the power source, and a power relay 37 and a control unit 35 that are switched by receiving a DC voltage Vcc2 through the control transistor 36. Corresponding to the control signal from Switching operation is performed by a drive integrated circuit (38) for outputting a trigger signal and a trigger signal applied from the drive IC (38) to supply power to the washing motor (11), the water supply valve (18), and the drain valve (21). It consists of a plurality of triacs (Triac) 39 to 41 for applying.

The operation process of the conventional washing machine configured as described above is as follows.

When the user puts laundry into the inner cylinder 7 of the washing and dehydrating tank 8 and then closes the door 3, the high-level DC voltage Vcc1 supplied from a predetermined DC power supply while the door switch 31 is turned on. The door switch 31 and the surge absorption resistor 32 are input to the control unit 35, and the control unit 35 determines the high level DC voltage Vcc1 input as described above as the door closing signal. .

Next, when the user inputs a washing condition (eg, washing course, washing time, water supply selection, etc.) through the key input unit 33 and inputs a start command, a key signal corresponding to the input data is inputted to the key input unit ( A power supply signal is input from the control unit 35 to the base terminal of the control transistor 36 from the control unit 35.

As the control transistor 36 is turned on by the power supply signal from the controller 35 and the DC voltage Vcc2 is applied to the coil of the power relay 37, the movable contact of the power relay 37 is switched on and washed. Commercial alternating current voltages from the outside are applied to both ends of the motor 11, the water supply valve 18, and the drain valve 21.

The trigger signal is output from the drive IC 38 by the control signal from the control unit 35, and the triacs 39 to 41 are driven by the trigger signal to wash the motor 11 and the water supply valve 18, respectively. When power is applied to the drain valve 21, the washing motor 11, the water supply valve 18, and the drain valve 21 are respectively driven to wash the laundry (for example, washing stroke, dehydration stroke, Rinsing stroke, etc.) is performed.

As described above, when the user opens the door 3 while the washing motor 11 is being driven as described above, the door switch 31 is turned off, and a low level signal is input to the controller 35 and the controller ( 35) determines this as a door open signal and outputs a power cut-off signal for cutting off the power applied to each load including the washing motor 11 to the base terminal of the control transistor 36. Pause the control operation.

As the control transistor 36 is turned off by the control signal applied from the control unit 35 as described above, the supply of the DC voltage Vcc2 to the coil of the power relay 37 is cut off, which causes the relay 37 to be demagnetized. As the movable contact of the relay 37 is switched to the switching off state and the relay 37 is switched to the switching off state, the supply of the commercial AC voltage to the washing motor 11 is stopped, so that the driving of the washing motor 11 is stopped. Is stopped.

That is, even when the door 3 is opened while the washing motor 11 is being driven, the power relay 37 is turned off by the power cutoff signal applied from the control unit 35 so that the supply of power to the washing motor 11 is stopped. Since it is interrupted, the user may be injured by the inner cylinder 7 of the pulsator 9 or the washing and dehydrating tank 8 that is rotated by receiving the rotational force from the washing motor 11, or the laundry may be thrown outward. Accidents are prevented beforehand.

However, in the conventional washing machine configured as described above, when the door open signal input line of the control unit is disconnected and the control unit does not detect the open state of the door or malfunctions due to noise, the power is not output. Since the breaker is not operated, there is a problem that the washing motor is driven by continuously supplying power even when the door is opened.

Therefore, the present invention has been made in order to solve the problems of the prior art as described above, even if the power cut signal is output from only one of the door switch and the control unit, the power supply of the washing motor is cut off by the power cut off washing motor An object of the present invention is to provide a door opening safety device of a washing machine that can stop the driving of the.

1 is a schematic cross-sectional view showing the structure of a general washing machine;

2 is a schematic circuit diagram illustrating a drive control apparatus for a washing machine according to a conventional example;

Figure 3 is a schematic circuit diagram showing a drive control device of the washing machine to which the door opening safety device of the washing machine according to an embodiment of the present invention,

Figure 4 is a schematic circuit diagram showing a drive control device of the washing machine to which the door opening safety device of the washing machine according to another embodiment of the present invention,

5 is a schematic circuit diagram showing another embodiment of the door open detection unit shown in FIG. 4;

FIG. 6 is a schematic circuit diagram illustrating still another embodiment of the door open detection unit illustrated in FIG. 4;

Figure 7 is a schematic circuit diagram showing another embodiment of the door open detection unit shown in FIG.

<Description of the symbols for the main parts of the drawings>

3: door 11: washing motor

100, 200: door open detection unit 102, 201: door switch

101, 103, 202, and 203: resistors 130 and 300: control unit

140: power cut-off unit 141, 142: transistor

143: power relay

The door opening safety device of the washing machine according to the present invention for achieving the above object is a door opening detection unit for outputting a door opening signal and a power cutoff signal when the door is opened, and when the door opening signal is input from the door opening detection unit. And a control unit for outputting a power cutoff signal, and a power cutoff unit for blocking the supply of power to the washing motor when a power cutoff signal is input from at least one of the door opening detecting unit and the control unit.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a schematic circuit diagram showing a driving control apparatus of a washing machine to which a door opening safety device of a washing machine is applied according to a preferred embodiment of the present invention. As can be seen from the same drawing, the door opening safety device of the present invention is shown. The driving control apparatus of the washing machine to which the washing machine is applied includes a door open detection unit 100, a key input unit 110, an operation display unit 120, a control unit 130, a power cutoff unit 140, a drive IC 150, and a plurality of tri The liquid 160, 161, 162, the washing motor 11, the water supply valve 18 and the drain valve 21, the internal structure of the washing machine to which the present invention is applied is the same as Figure 1, the same for the same components Reference numerals will be given and duplicated descriptions will be omitted.

In FIG. 3, the door open detection unit 100 is for inputting a door open signal to the control unit 130 when the door 3 is opened and inputting a power cutoff signal to the power cutoff unit 140. One end is connected in series to the DC voltage (Vcc1) and the other end is turned on / off in accordance with the opening and closing of the first resistor 101 and the door (3) connected in series to one signal input terminal of the control unit 130 A door switch 102 connected in parallel to the first resistor 101 and a second resistor having one end connected in series to the other end of the door switch 102 and the other end connected to one side of the power cut-off unit 140. It consists of 103.

The key input unit 110 includes a plurality of selection buttons for inputting washing conditions, and when a user operates the selection button, a corresponding key signal is applied to the controller 130, and the driving display unit 120 is provided. The operation state of the washing machine is displayed by the display signal from the controller 130.

The control unit 130 determines a driving condition selected by the user through a key signal applied from the key input unit 110, and performs the washing motor 11 and the water supply valve 18 to perform each stroke according to the determined driving condition. And a control signal for driving the drain valve 21 to the drive IC 150 and a display signal for displaying the driving state to the driving display unit 120.

In addition, the controller 130 determines the opening / closing state of the door 3 according to a signal input from the door opening detecting unit 100, and if the door 3 is opened while the washing motor 11 is being driven, the washing motor ( 11) outputs a power cutoff signal to cut off the power applied to the power cutoff unit 140.

When the power cutoff signal is input from at least one of the door open detection unit 100 and the control unit 130, the power cutoff unit 140 includes a washing motor 11, a water supply valve 18, and a drain valve 21. In order to cut off the applied power, the base terminal is connected to the power cutoff signal output terminal of the control unit 130 and the emitter terminal is grounded, and the base terminal of the door opening detecting unit 100. The second control transistor 142 connected to the door switch 102 via the second resistor 103 and the emitter terminal is connected to the collector terminal of the first control transistor 141, and one end of which is commercially applied. A movable contact (a) and one end connected to an alternating voltage and commonly connected to the washing motor 11, the water supply valve 18, and the drain valve 21 are connected to a DC voltage (Vcc2) and the other end is used for the second control. A nose connected to the collector end of transistor 142 It consists of a power relay 143 consisting of one (b).

The drive IC 150 generates a trigger signal for driving the washing motor 11, the water supply valve 18, and the drain valve 21 according to a control signal from the controller 130. 162 respectively, and the plurality of triacs 160 to 162 are switched by respective trigger signals applied from the drive ICs 150 to wash the motor 11, the water supply valve 18, and the drain valve. Use (21) to apply a commercial ac voltage.

An operation example of the present invention configured as described above will be described in detail with reference to FIG. 3.

First, when a commercial AC voltage is applied to a washing machine through a power cable not shown from the outside, a DC voltage of a predetermined level required for driving each part of the washing machine by a power supply device not shown is applied to the commercial AC voltage applied to the washing machine. 3 is supplied to each part of the washing machine shown in FIG. 3, and each part of the washing machine including the controller 130 is initialized by the DC voltage supplied from the power supply device.

At this time, when the user puts laundry into the inner cylinder 7 of the washing and dewatering tank 8 and closes the door 3, the door switch 102 is switched on, and the door switch 102 is turned on. The first resistor 101 and the second resistor 103 of the opening detection unit 100 are connected in parallel to each other.

As described above, since the first resistor 101 and the second resistor 103 of the door open detection unit 100 are connected in parallel to each other, the DC voltage Vcc1 supplied from the power supply device is the first resistor 101. And divided by the second resistor 103 to be applied to the base terminal and the controller 130 of the second control transistor 142.

As described above, as the DC voltage divided by the first resistor 101 and the second resistor 103 is applied to the base terminal of the second control transistor 142, the second control transistor 142 is turned on.

At the same time, as described above, the controller 130 determines the DC voltage of the level (for example, about 3 volts) input by being divided by the first resistor 101 and the second resistor 103 as a door closing signal. 1 A power supply signal is output to the base terminal of the control transistor 141.

As the first control transistor 141 is turned on by the power supply signal applied from the controller 130, both the first control transistor 141 and the second control transistor 142 are turned on. DC voltage (Vcc2) supplied from is applied to the coil (b) of the relay 143, the coil (b) of the relay 143 is excited and the coil (b) of the relay 143 is excited The movable contact a of the relay 143 is switched to the switched on state.

Then, when the user operates the selection button of the key input unit 110 to input the washing conditions (for example, washing course, washing time, water supply selection, etc.) and then operates the washing start button, the user enters from the key input unit 110. The key signal corresponding to the button operation is applied to the control unit 130, and the control unit 130 determines the washing condition input by the user by the key signal applied from the key input unit 110 and washes according to the determined washing condition. The driving of the motor 11, the water supply valve 18, and the drain valve 21 is controlled to perform washing, rinsing, or dehydrating strokes.

For example, a case of performing a double laundry administration will be described.

In performing the laundry administration, the controller 130 outputs a control signal for supplying the washing water to the washing and dehydrating tank 8 to the drive IC 150 according to the washing condition selected by the user, and the controller 130. The trigger signal for opening the water supply valve 18 from the drive IC 150 is applied to the second triac 161 by a control signal from the drive IC 150.

The second triac 161 is switched by a trigger signal applied from the drive IC 150, and a commercial AC voltage from the outside is supplied to the water supply valve 18 through the second triac 161 operated by the switching IC. It is applied to the water supply valve 18 is opened.

Washing and dehydration tank with the detergent dissolved in the detergent dissolving unit 19 through the detergent dissolving unit 19 through the water supply means 17 through the water supply means 17 through the open water supply valve 18 Watered by (8).

At the same time, the control unit 130 detects the water level in the washing and dehydration tank 8 through the water level sensor, not shown, and the detected water level is abnormal of a predetermined water level (for example, a water level corresponding to the washing condition selected by the user). On the other hand, a control signal for stopping water supply is output to the drive IC 150.

The output of the trigger signal for the second triac 161 from the drive IC 150 is stopped by the control signal from the controller 130 and the input of the trigger signal from the drive IC 150 is stopped. 2 triac 161 is switched to the switching off state to stop the supply of the commercial AC voltage to the water supply valve 18, the supply of the commercial AC voltage through the second triac 161 is stopped. (18) is closed and the water supply to the washing and dewatering tank 8 is stopped.

Then, a control signal for driving the washing motor 11 from the controller 130 is output to the drive IC 150, and the washing motor 11 from the drive IC 150 by the control signal from the controller 130. Is applied to the first triac 160.

The first triac 160 is switched by a trigger signal applied from the drive IC 150, and a commercial AC voltage from the outside is supplied to the washing motor 11 through the first triac 160 operated by the switching IC. Is applied to the washing motor 11 is driven.

The rotational force of the driven washing motor 11 is transmitted to the power transmission unit 15 via the belt 13, and the pulsator is driven by the rotational force of the washing motor 11 transmitted to the power transmission unit 15. 9) is left and right stirred to form a water stream in the wash water in the washing and dehydration tank (8).

Pressure is applied to the wash water by the water flow formed along the left and right stirring of the pulsator 9, and when the adsorbed laundry or the foreign matter is separated from the laundry by the pressure applied to the wash water, washing is performed.

Here, the controller 130 counts the washing time by the built-in timer and when the counted washing time passes a predetermined time (for example, washing time corresponding to the washing condition selected by the user), the washing motor 11 of the washing motor 11 A control signal for stopping driving and a control signal for draining the wash water of the washing and dewatering tank 8 are output to the drive IC 150.

The control signal from the control unit 130 stops the output of the trigger signal for driving the washing motor 11 from the drive IC 150 and the trigger signal for opening the drain valve 21 is the third triac ( 162).

As the output of the trigger signal for driving the washing motor 11 from the drive IC 150 is stopped, the first triac 160 is switched to the off state to supply the commercial AC voltage to the washing motor 11. As a result, the driving of the washing motor 11 is stopped as the supply of the commercial AC voltage through the first triac 160 is stopped.

In addition, the third triac 162 is switched by the trigger signal output from the drive IC 150, and the commercial AC voltage from the outside is supplied to the drain valve through the third triac 162 operated by the switching. It is applied to (21) and the drain valve 21 is opened, as the drain valve 21 is opened, the washing water in the washing and dehydration tank (8) is drained to the outside through the drain hose (23).

The control unit 130 detects the water level in the washing and dewatering tank 8 through the water level sensor, not shown, and if it is determined that the washing water in the washing and dewatering tank 8 is drained, a control signal for stopping the draining is provided. Output to the drive IC 150.

The output of the trigger signal for opening the drain valve 21 from the drive IC 150 is stopped by the control signal from the controller 130, and the output of the trigger signal from the drive IC 150 is stopped. 3 triac 162 is switched to the switching off state, the supply of the commercial AC voltage applied to the drain valve 21 is stopped, and the supply of the commercial AC voltage to the drain valve 21 is stopped, the drain valve 21 ) Is closed.

As a result, the washing cycle is terminated, and then a rinsing stroke or a dehydration stroke is performed according to the washing condition selected by the user.

However, when the user arbitrarily opens the door 3 during the washing stroke, the rinsing stroke, or the dehydrating stroke as described above, that is, while the washing motor 11 is being driven, the door of the door opening detecting unit 100 The switch 102 is switched off so that the connection between the first resistor 101 and the second resistor 103 is released and applied to the base end of the second control transistor 142 through the door switch 102. The supply of the DC voltage is interrupted and the second control transistor 141 is turned off.

Accordingly, the control unit 130 receives a DC voltage Vcc1 of an undivided intact level (for example, about 5 volts), and the control unit 130 receives a DC voltage Vcc1 of an undivided intact level. Is determined as a door open signal, and a power supply cutoff signal is applied to the base terminal of the first control transistor 141, and at the same time, all control operations relating to the stroke that has been performed so far are suspended.

The first control transistor 141 is turned off by the power cutoff signal applied from the controller 130.

As described above, as the first control transistor 141 and the second control transistor 141 are turned off, the supply of the DC voltage Vcc2 applied to the coil b of the power relay 143 is stopped so that the power relay 143 The coil b is demagnetized, and as the coil of the power relay 143 is demagnetized, the movable contact a of the power relay 143 is switched to the switched off state.

As the movable contact (a) of the power relay 143 is switched to the switched off state, the supply of the commercial AC voltage to the washing motor 11, the water supply valve 18, and the drain valve 21 is interrupted, thereby washing the washing motor 11. At the same time, the water supply valve 18 and the drain valve 21 are closed.

As the driving of the washing motor 11 is stopped as described above, the rotation of the inner cylinder 7 of the pulsator 9 or the washing and dehydrating tank 8 which is operated by receiving rotational force from the washing motor 11 is stopped. By the inner cylinder 7 of the washing and dewatering tank 8 in which the laundry pops out from the washing and dewatering tank 8 or the user's body (for example, a hand, etc.) is rotated while the door 3 is opened. Safety accidents such as injuries are prevented.

If, as described above, each stroke is performed and the washing motor 11 is being driven, a disconnection is generated in the signal input line between the door opening detecting unit 100 and the control unit 130 so that the control unit 130 opens the door 3. Of the first control transistor of the power cut-off unit 140 when a failure occurs in the control unit 130, such as not detecting the open state of the control unit or malfunctioning by the control unit 130 to output the power cut-off signal. 141 maintains a turn-on state.

However, as described above, even if the first control transistor 141 remains turned on due to a failure of the controller 130, the door switch 102 is turned off in accordance with the opening of the door 3, and thus the second control transistor 142 is closed. Since the power relay 143 is switched to the switching off state while the power supply 143 is turned off, the supply of the commercial AC voltage to the washing motor 11 is stopped and the driving of the washing motor 11 is stopped.

That is, even if a failure occurs in the controller 130 and the power cutoff signal is not output from the controller 130, the power cutoff signal from the door open detection unit 100, that is, the low level of the door switch 102 is opened. The power cutoff unit 140 is operated by the voltage, and the supply of power to the washing motor 11 is cut off by the power cutoff unit 140.

Thereafter, when the user closes the door 3, the door switch 102 of the door open detection unit 100 is turned on, and as the door switch 102 is turned on, the first resistance 101 of the door open detection unit 100 is turned on. ) And the second resistor 103 are connected in parallel.

As described above, since the first resistor 101 and the second resistor 103 of the door open detection unit 100 are connected in parallel to each other, the DC voltage Vcc1 supplied from the power supply device is the first resistor 101. The voltage is divided by the second resistor 103 and applied to the base terminal of the second control transistor 142 of the power cutoff unit 140 and the controller 130.

As described above, as the DC voltage divided by the first resistor 101 and the second resistor 103 is applied to the base terminal of the second control transistor 142, the second control transistor 142 is turned on.

At the same time, the controller 130 determines the DC voltage of the input level divided by the first resistor 101 and the second resistor 103 as the door closing signal as described above, and determines the base terminal of the first control transistor 141. Outputs the power supply signal.

As the first control transistor 141 is turned on by the power supply signal applied from the controller 130, both the first control transistor 141 and the second control transistor 142 are turned on. The DC voltage Vcc2 supplied from the power relay 143 is applied to the coil b of the power relay 143, and the coil b of the power relay 143 is excited so that the movable contact a of the power relay 143 is switched on. Is switched to.

Next, the controller 130 controls the washing motor 11, the water supply valve 18, and the drain valve 21 to perform the remaining stroke which has been suspended.

Meanwhile, another embodiment of the present invention will be described with reference to FIGS. 4 to 7.

4 is a schematic circuit diagram illustrating a driving control apparatus for a washing machine to which a door opening safety device of a washing machine is applied according to another embodiment of the present invention. As shown in FIG. The driving control apparatus of the washing machine to which the door opening safety device of the washing machine is applied is different from the configuration of the door opening detecting unit 200 and the control unit 300 compared to FIG. In the following description, only the configuration and operation of the door opening detecting unit 200 and the control unit 300 will be described in order to give the same reference numerals and to avoid duplicate descriptions.

As shown in FIG. 4, the door opening detecting unit 200 according to another embodiment of the present invention is turned on / off according to opening and closing of the door 3, and a door switch having one end connected in series with a DC voltage Vcc1. 201, a first resistor 202 having one end connected in series with one end of the door switch 201 and the other end connected in series with one signal input terminal of the controller 300, and one end having the first resistor 202. ) And a second resistor 203 connected in parallel with the other end and connected in series with the base end of the first control transistor 142.

When the high level DC voltage is input from the door opening detecting unit 200, the control unit 300 determines this as a door closing signal, and when the low level voltage is input, determines the door opening signal. Since the operation of FIG. 3 is the same as the controller 130 shown in FIG. 3, a redundant description will be omitted.

An operation example according to another embodiment of the present invention configured as described above will be described.

As described above, the driving control apparatus of the washing machine to which the door opening safety device of the washing machine according to another embodiment of the present invention is applied has a different configuration from that of the door opening detecting unit 200 and the control unit 300 compared to FIG. 3. Also, in operation 300, only the operation of determining the door open signal is different. In addition, only the operation of the signal input / output between the door open detection unit 200 and the control unit 300 will be described in order to avoid duplicate explanation. Shall be.

When the user closes the door 3, the door switch 201 of the door open detection unit 200 is turned on, and as the door switch 201 is turned on, the first resistor 202 and the second resistor 203 mutually interact with each other. Are connected in parallel.

As described above, as the first resistor 202 and the second resistor 203 are connected in parallel with each other, the DC voltage Vcc1 applied from the power supply illustrated in the drawing is the first resistor 202 and the second resistor 203. The voltage is divided by the reference signal) and input to the base terminal of the second control transistor 142 and the door open signal input terminal of the controller 300.

As described above, when the DC voltage divided by the first resistor 202 and the second resistor 203 is applied to the base terminal of the second control transistor 142, the second control transistor 142 is turned on.

At the same time, the control unit 300 divides the DC voltage inputted by the first resistor 202 and the second resistor 203 as the high level as described above, and thus, the controller 300 determines the first control transistor 141 as a door closing signal. Outputs power supply signal to the base of

If the user opens the door 3, the door switch 201 of the door open detection unit 200 is turned off, and as the door switch 201 is turned off, the direct current flows to the base end of the second control transistor 142. While the supply of the voltage is stopped, the second control transistor 142 is turned off, while a low level signal is input to the controller 300.

As described above, the control unit 300 determines the low level signal due to the door switch 201 to be turned off, applies the power cutoff signal to the base terminal of the first control transistor 141, and performs it up to now. Pause all control actions related to the stroke.

On the other hand, according to another embodiment of the present invention as described above, regardless of the high and low signal level, the control unit 300 is to determine the high level signal as the door closing signal and the low level signal as the door open signal 5 to 7, the configuration of the door opening detecting unit 200 can be freely modified.

That is, the door opening detecting unit 200 is configured by only the door switch 201 without installing a separate resistor as shown in FIG. 5, or as shown in FIG. 6, the door switch 201 and the second control transistor. A surge absorbing resistor 203 is provided only between the base ends of 142, or the surge absorbing resistor 202 is provided only between the door switch 201 and the control unit 300 as shown in FIG. Can be installed and configured.

As described above, according to the present invention, even if the power cutoff signal is output from only one of the door switch and the controller, the power applied to the washing motor is cut off by the power cutoff unit, so even when the door is opened due to a failure of the controller side, There is an effect that can prevent the accident that the motor is driven.

Claims (7)

In the washing machine with the (correction) door, A door open detection unit for detecting a door open state and outputting a door open signal and a power cut signal, respectively; A control unit which outputs a power cutoff signal when a door opening signal is input from the door opening detecting unit; The door opening safety device of the washing machine, characterized in that the power cut-off unit which cuts off the supply of power to the washing motor when a power cut-off signal is input from at least one of the door open detection unit and the control unit. The method of claim 1, wherein the door open detection unit, A plurality of resistance elements connected in parallel with each other, one end of which is commonly connected to a predetermined DC power source, and the other end of which is connected to a signal input terminal of the controller and one side of the power interrupting unit; The door opening safety device of a washing machine, characterized in that the switching element is switched on / off according to the opening and closing of the door to switch the connection between the plurality of resistance elements. The method of claim 1, wherein the door open detection unit, On / off according to the opening and closing of the door, the door opening safety device of the washing machine, characterized in that the one end is connected to a predetermined DC power source and the other end is connected to the signal input terminal of the control unit and one side of the power cut-off unit in common. The door opening safety device of a washing machine according to claim 3, wherein the other end of the switching element is connected to a signal input end of the control unit via a resistance element. The door open safety device of claim 3, wherein the other end of the switching device is connected to one side of the power cutoff unit through a resistance device. The power cut-off unit according to any one of claims 1 to 5, wherein A plurality of control switching elements connected in series to each other and respectively operated by power cutoff signals applied from the door opening detecting unit and the control unit; The door opening safety device of the washing machine, characterized in that the switching operation by the voltage applied through the plurality of control switching elements are configured to switch or disconnect the connection between the washing motor and the power source. The method of claim 6, wherein the plurality of control switching elements, Door opening safety device for a washing machine, characterized in that the transistor.