JP2008104500A - Opening/closing detecting device for lid switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an opening/closing detecting device for a lid switch which does not erroneously detect the opening/closing of the lid switch even if a specified constituent element fails by foreign noises or the like. <P>SOLUTION: The lid switch 15 which opens/closes while in association with the opening/closing of a lid of the opening section is installed on a washing machine body. A power source port PE (5 V), two input ports PA and PB as a specified constituent element, and a grand port GND (0 V) are installed on a microcomputer 19. With the power source port PE, the input ports PA and PB, and the grand port GND, a detection circuit 20 which outputs a detection signal by detecting the opening/closing of the lid switch 15 is connected. Then, the microcomputer 19 determines the opening/closing of the lid switch 15 on the AND condition of the detection signal which is given to the input ports PA and PB. Also, diodes 23 and 24 for surge absorbing as a specified constituent element which are serially connected with each other are connected in parallel with the lid switch 15. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an open / close detection device for a lid switch that opens and closes in response to opening / closing of a lid provided in an opening of an electric device body.

In a fully automatic washing machine having a vertical axis, which is an electrical appliance, for example, a home appliance, a lid is provided at the opening on the top surface of the washing machine body to open and close the opening, and the washing machine body opens and closes in conjunction with opening and closing of the lid. And a detection circuit for detecting the opening and closing of the lid switch and outputting a detection signal. The detection signal of the detection circuit is input to the input port of the microcomputer. ing. When the microcomputer detects the opening of the lid through the lid switch and the detection circuit, for example, during the dehydration process, the microcomputer turns off the power of the washing machine motor that drives the rotating tub serving as the washing tub and dehydration tub, and rotates the rotation. Appropriate control is performed to operate a brake device that applies braking to the tank (see, for example, Patent Document 1).
JP-A-11-156085

  The detection circuit and microcomputer are composed of many components such as resistors, capacitors, diodes, input ports, etc. When any one of these components fails or breaks due to external noise, etc., the lid switch opens and closes, Open / close cannot be detected. For example, when a microcomputer input port fails due to external noise or the like, the detection signal of the input port may become a signal that causes the lid switch to be closed, and it is impossible to detect the opening of the lid. Therefore, there is a problem that proper control cannot be performed.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a lid switch opening / closing detection device that does not erroneously detect opening / closing of the lid switch even if a specific component fails due to external noise or the like. There is to do.

A lid switch open / close detection device according to claim 1 of the present invention is a lid switch that opens and closes in response to opening / closing of a lid provided in an opening of an electric device body, and detects and detects the opening / closing of the lid switch. A detection means for outputting a signal; and a control means having an input port for inputting a detection signal from the detection means, and determining the opening / closing of the lid switch according to the state of the detection signal, the detection means or the control means A plurality of specific constituent elements among the constituent elements are provided, and the control means determines opening / closing of the lid switch based on an action of a logical condition of the plurality of constituent elements. .
According to such a configuration, even if any one of the specific components fails due to external noise or the like, the remaining components operate normally, for example, even though the lid switch is open, Open / close of the lid switch is not erroneously detected, for example, it is not detected as closed.

According to a fourth aspect of the present invention, there is provided a lid switch open / close detection device that detects a lid switch that opens and closes in response to opening and closing of a lid provided in an opening of an electric device body, and detects the opening and closing of the lid switch. Detection means for outputting a detection signal and control means for determining whether the lid switch is opened or closed according to the state of the detection signal, the control means having an input port for inputting the detection signal from the detection means. When the detection signal from the detection means is an unstable signal that cannot be determined at either the set high level or low level, it is determined as abnormal.
According to such a configuration, the control means determines that there is an abnormality when any of the constituent elements fails due to external noise or the like and the detection signal is set to an unstable signal that cannot be determined as either the high level or the low level. Therefore, it is possible to prevent the lid switch from being erroneously opened or closed.

  Since the present invention judges the opening / closing of the lid switch based on the action of the logical conditions of a plurality of components, even if any of the plurality of components fails due to external noise or the like, the lid switch is erroneously detected. There is an effect that there is nothing to do.

A first embodiment in which the present invention is applied to a vertical automatic washing machine will be described below with reference to FIGS.
FIG. 3 is a vertical sectional side view showing a part of a fully automatic washing machine having a vertical axis. A washing machine main body 1 as an electric device main body includes a rectangular box-shaped outer box 2 and a top cover 3 provided on the upper surface of the outer box 2. The water tank 4 is elastically suspended inside the outer box 2 by an elastic suspension mechanism 5 (in reality, only one is shown) including a support shaft 5a and a spring 5b. A rotating tub 6 serving as a washing tub and dewatering tub is rotatably disposed. A number of dewatering holes 6 a are formed in the peripheral wall portion of the rotating tub 6. Further, a balance ring 7 is provided at the upper end portion of the rotating tub 6. Further, a stirring blade (stirring body) 8 is rotatably disposed on the inner bottom portion of the rotating tank 6.

  A mechanism unit 9 having a tank shaft 9a and a stirring shaft 9b is disposed on the outer bottom of the water tank 4 in the outer box 2, and the rotating tank 6 is connected to the tank shaft 9a, and the upper end of the stirring shaft 9b. A stirring blade 8 is connected to the part. Moreover, the outer rotor 10a of the washing machine motor (load) 10 which consists of a brushless DC motor is connected with the lower end part of the stirring shaft 9b. The washing machine motor 10 rotates the agitating blade 8 forward and backward in the washing process and the rinsing process, and rotates the rotating tub 6 at a high speed in the dehydration process. A drain port 11 is formed at the bottom of the water tank 4, and a drain hose 13 is connected to the drain port 11 via a drain valve 12.

  The top cover 3 is provided with a lid 14. The lid 14 opens and closes the opening of the top cover 3, that is, the opening of the rotary tank 6 through the opening of the water tank 4. In the top cover 3, a lid switch 15 made of a micro switch is disposed in the vicinity of the open / close base end portion of the lid 14, and this lid switch 15 is interlocked (responsive) to the opening / closing of the lid 14. Open and close. An operation panel 16 is provided on the upper surface of the front portion of the top cover 3, and a control unit 18 including an open / close detection device 17 (see FIG. 1) for the lid switch 15 is disposed on the back side thereof. .

Now, the configuration of the open / close detection device 17 of the lid switch 15 will be described with reference to FIG.
The microcomputer 19 as control means includes a DC 5V power port PE, a plurality of input ports PA and PB as specific components, and a 0V ground port GND. In addition, the microcomputer 19 includes an operation unit of the control unit 18 (not shown), an input port to which the water level switch for detecting the water level of the water tank 4 and the lid switch 15 described above are connected, and a water supply valve for supplying water into the water tank 4 (Not shown) and an output port to which a brake device (not shown) serving as a load for applying a braking force to the drain valve 12, the washing machine motor 10, and the rotating tub 6 is connected.

  The microcomputer 19 is connected to the power supply port PE, the first input port PA, the second input port PB, and the ground port GND with a detection circuit 20 serving as detection means that constitutes the open / close detection device 17 together with the microcomputer 19. Yes. That is, the power port PE of the microcomputer 19 is connected to one input terminal 21 of the pair of input terminals 21 and 22, and the lid switch 15 is connected between the input terminals 21 and 22. A plurality of two surge absorbing diodes 23 and 24 as specific components are connected in series. That is, the two diodes 23 and 24 are connected in parallel to the lid switch 15 after being connected in series with each other.

  The other input terminal 22 of the input terminals 21 and 22 is connected to the ground terminal GND of the microcomputer 19 through a series circuit of a resistor 25a and a capacitor 25b constituting a noise filter (low-pass filter) 25, A surge absorbing diode 26 is connected in parallel to the series circuit of the resistor 25a and the capacitor 25b. The common connection point of the resistor 25a and the capacitor 25b is bifurcated, and the first and second branch ends are respectively connected to the input ports PA and PB of the microcomputer 19 via the backflow prevention diodes 27 and 28, respectively. It is connected. The cathodes of the diodes 27 and 28 are connected to the ground terminal GND of the microcomputer 19 through resistors 29 and 30, respectively.

Next, the operation of this embodiment will be described with reference to FIG.
When the lid 14 is closed, the lid switch 15 interlocked therewith is also in a closed state. Therefore, the detection signals given to the first input port PA and the second input port PB are set to a preset high level H ( 5V) (see pattern 1 in FIG. 2). Thereby, the microcomputer 19 detects that the detection signals given to the input ports PA and PB are both at the high level H, and the logical product (AND) output as the logical output of both detection signals becomes the high level H. It is determined that 15 is closed. When the microcomputer 19 determines that the lid switch 15 is closed, for example, in the dehydration process of the washing operation, the drain valve 12 is energized and opened, and the washing machine motor 10 is energized and rotated. The rotating tank 6 is rotated at a high speed, and dehydration is executed.

  When the lid 14 is opened, the lid switch 15 is also opened in conjunction with this, so that the detection signals given to the first input port PA and the second input port PB are set at a preset low level. L (0 V) (see pattern 4 in FIG. 2). As a result, the microcomputer 19 determines that the lid switch 15 is open when both of the detection signals applied to the input ports PA and PB are at the low level L and the logical product (AND) output of both detection signals is at the low level L. To do. When the microcomputer 19 determines that the lid switch 15 is open, for example, when the dehydration process is in progress, the microcomputer 19 is turned off and the brake device (not shown) is operated to bring the rotating tub 6 into operation. Appropriate control is performed so that the braking force is applied.

  By the way, when the lid 14 is opened and the lid switch 15 is also opened, the first input port PA, which is a specific component of the microcomputer 19, breaks down due to external noise or the like. Is short-circuited to the power supply port PE, the input port PA is always at the high level H (5 V). In this case, conventionally, the microcomputer erroneously determines that the lid switch is closed.

  On the other hand, in this embodiment, even if the input port PA is short-circuited to the power supply port PE and becomes high level H, the detection signals of the input ports PA and PB are high level H and low level L (in FIG. 2). The logical product (AND) output of both detection signals becomes low level L, and the microcomputer 19 determines that the lid switch 15 is open.

  When the lid 14 is opened and the lid switch 15 is also opened, the second input port PB, which is a specific component of the microcomputer 19, breaks down due to external noise or the like. For example, the input port PB Is short-circuited to the power supply port PE, the input port PB is always at the high level H (5 V). However, in this case, the detection signals of the input ports PA and PB are low level L and high level H (see pattern 3 in FIG. 2), and the logical product (AND) output of both detection signals is low level L. 19 determines that the lid switch 15 is open.

  On the other hand, in this embodiment, two surge absorbing diodes 23 and 24 are provided in series as specific components of the detection circuit 20. This is to absorb a surge generated when the lid switch 15 opens and closes when a high voltage external noise or the like is applied. Since these diodes 23 and 24 are connected in series, the cutoff characteristic of the current flowing in the direction from the power supply port PE to the input port PA is a logical OR condition, and the lid switch 15 is opened ( Even when one of the diodes, for example, 23 is destroyed and short-circuited due to external noise or the like when the lid 14 is in the open state, the 5 V voltage of the power supply port PE is applied to the input ports PA and PB due to the cutoff characteristics of the remaining diode 24. Application of the input ports PA and PB to the high level H is prevented.

  As described above, according to this embodiment, the microcomputer 19 is provided with the two input ports PA and PB as specific components, and the microcomputer 19 indicates opening and closing of the lid switch 15 provided from the detection circuit 20. Since the opening / closing of the lid switch 15 is determined according to the logical product condition of the detection signal, when the lid switch 15 is open, either the input port PA or PB fails due to external noise or the like, and the power port PE When a short circuit occurs, the lid switch 15 is determined to be open, and the lid switch 15 is not erroneously determined to be closed.

  Further, according to this practical example, since two surge absorbing diodes 23 and 24 are provided in series as specific components of the detection circuit 20, these diodes 23 and 24 are input from the power supply port PE. In terms of the cutoff characteristic of the current flowing in the port PA, the logical condition is an OR condition. Therefore, when the lid switch 15 is in the open state (the lid 14 is open), one diode, for example, 23 is external. Even if a breakdown is short-circuited due to noise or the like, the 5 V voltage of the power supply port PE is applied to the input ports PA and PB due to the cutoff characteristics of the remaining diodes 24 (the input ports PA and PB become high level H). This prevents the microcomputer 19 from erroneously determining that the lid switch 15 is closed.

FIG. 4 shows a second embodiment of the present invention, in which the same parts as those in the above-described embodiment (particularly FIG. 1) are denoted by the same reference numerals.
In the second embodiment, the microcomputer 19 has the input port PB omitted, and the detection circuit 31 serving as detection means in place of the detection circuit 20 includes the surge absorbing diode 24 and the backflow prevention diode in the detection circuit 20. The diodes 27 and 28 and the resistor 30 are omitted. The detection circuit 31 constitutes an open / close detection device 32 together with the microcomputer 19.

  Thus, when the lid switch 15 is closed, the detection signal given to the input port PA of the microcomputer 19 is at the high level H, and when the lid switch 15 is opened, the detection signal given to the input port PA. Becomes the low level L, and the microcomputer 19 determines whether the lid switch 15 is opened or closed according to the high level H or low level L state of the communication signal applied to the input port PA.

  However, any of the surge absorbing diodes 23 and 26 and the resistor 25a, the capacitor 25b, and the resistor 29 of the noise filter 25, which are constituent elements of the detection circuit 31, may fail or deteriorate due to external noise or the like and perform a predetermined action. When it is lost, the voltage of the input port PA does not become the set high level H (5 V) or low level L (0 V), regardless of whether the lid switch 15 is opened or closed. For example, it may be 3V or 3.5V.

Therefore, when the microcomputer 19 cannot determine that the detection signal given to the input port PA is the set high level H (5 V) or low level L (0 V), it determines that this is abnormal, for example, If the dehydration process is in progress, an appropriate control such as turning off the washing machine motor 10 and operating the brake device is performed, and display means (not shown) that the detection circuit 31 related to the lid switch 15 is abnormal Display.
Therefore, according to the second embodiment, it is possible to prevent erroneous determination of opening / closing of the lid switch 15 even if the components of the detection circuit 31 fail or deteriorate.

The present invention is not limited to the embodiments described above and shown in the drawings, and can be expanded and modified as follows.
In the first embodiment, when the input ports PA and PB are the patterns 2 and 3 shown in FIG. 2, the microcomputer 19 determines that the input port is abnormal and displays that fact on the display means. Good.
In the above embodiment, the two input ports PA and PB and the two surge absorbing diodes 23 and 24 are provided as specific components, but these may be provided in a plurality of three or more. Good.

In the above embodiment, a micro switch is used as the lid switch 15, but a permanent magnet and a reed switch may be used instead.
The above embodiment is a case where the present invention is used like a vertical automatic washing machine, but may be applied to a horizontal automatic washing machine, and further has a lid for opening and closing the opening. The present invention may be applied to household appliances such as dryers, dishwashers, and microwave ovens, and can also be applied to general electric devices having a lid that opens and closes the opening of the main body of the electric device.

Electrical configuration diagram showing a first embodiment of the present invention Action diagram Schematic longitudinal section FIG. 1 equivalent view showing a second embodiment of the present invention.

Explanation of symbols

  In the drawings, 1 is a washing machine body (electric equipment body), 6 is a rotating tub, 10 is a washing machine motor (load), 14 is a lid, 15 is a lid switch, 17 is an open / close detection device, 18 is a control unit, 19 is Microcomputer (control means), 20 is a detection circuit (detection means), 23 and 24 are surge absorbing diodes (specific components), 25 is a noise filter, 31 is a detection circuit (detection means), and 32 is open / close detection Devices, PA and PB indicate input ports (specific components).

Claims (4)

A lid switch that opens and closes in response to opening and closing of the lid provided in the opening of the electric device body;
Detecting means for detecting opening and closing of the lid switch and outputting a detection signal;
It has an input port for inputting a detection signal from the detection means, and includes a control means for determining opening / closing of the lid switch according to the state of the detection signal,
A plurality of specific components among the components constituting the detection means or the control means are provided, and the control means determines opening / closing of the lid switch based on an action of a logical condition of the plurality of components. An opening / closing detection device for a lid switch.   The plurality of components are input ports of the control means, and the control means determines opening / closing of the lid switch based on a logical product condition of the states of detection signals input to these input ports. The lid switch open / close detection device according to claim 1.   The plurality of components are surge-absorbing diodes connected in parallel to the lid switch and connected in series to each other, and the control means controls the lid based on a logical sum condition of the cutoff action of these diodes. The lid switch open / close detection device according to claim 1, wherein the switch open / close is determined. A lid switch that opens and closes in response to opening and closing of the lid provided in the opening of the electric device body;
Detecting means for detecting opening and closing of the lid switch and outputting a detection signal;
It has an input port for inputting a detection signal from the detection means, and includes a control means for determining opening / closing of the lid switch according to the state of the detection signal,
The lid switch open / close detection device according to claim 1, wherein the control means determines that the detection signal is abnormal when the detection signal from the detection means is an unstable signal that cannot be determined at either a high level or a low level.

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