JP3985533B2 - Dishwasher - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dishwasher having a configuration in which a washing motor provided with a safety switch is driven and the inside of a washing tank is heated by a heater.
[0002]
[Prior art]
Conventionally, this type of dishwasher / dryer is configured as shown in FIG. The configuration will be described below.
[0003]
As shown in FIG. 3, the cleaning tank 1 has an opening 2 in the front, and the opening 2 is opened and closed by a lid 3, and a horizontal nozzle 4 for injecting cleaning water is rotatably provided therein. A basket 6 for storing tableware 5 is arranged in the washing tank 1. The cleaning tank 1 is supported by a frame 7.
[0004]
The washing water in the washing tank 1 is warmed by the heater 8, sucked from the residue filter 11 provided in the drain port 10 by the washing pump 9, pumped to the horizontal nozzle 4, ejected toward the dishes 5, and circulated. It is washed by doing. When the cleaning process is completed, the cleaning water is drained out of the machine by the drain pump 12 provided at the lower part of the cleaning tank 1. The water supply valve 13 can open and close the supply of cleaning water to the cleaning tank 1 by opening and closing it.
[0005]
The user pulls the lid 3 forward and opens it, pulls out the basket 6, and places the dishes 5 to be cleaned on the basket 6. When all the dishes 5 have been arranged, the user pushes the basket 6 into the washing tub 1, closes the lid 3, turns on a power switch (not shown) connected to the controller 14, which is a control circuit, and needs it. Select the appropriate cleaning time and course, and press the start switch to start the cleaning process.
[0006]
FIG. 4 shows a circuit connection diagram of a conventional dishwasher / dryer.
[0007]
Conventionally, this type of dishwasher / dryer includes a commercial power supply 15, a power supply relay 16 that turns on and off the load, a safety switch 17 that opens and closes in conjunction with the lid 3 for safety, and a heater relay 18 that turns on and off the heater. Thus, the operation and stop are controlled by the drive signal from the control circuit 19. These contacts are provided with a power relay contact detection circuit 20, a safety switch contact detection circuit 21, and a heater relay contact detection circuit 22 for detecting a failure, and detect a contact open failure or a short circuit failure due to welding. However, by stopping the control circuit, etc., there was no unsafeness due to failure of the component parts. That is, when the power relay 16 has a short circuit failure, the power relay contact detection circuit 20 detects the failure and stops the device.
[0008]
Display means 23 and input means 24 are connected to control circuit 19 to exchange information with the user. The commercial power supply 15 supplies power to the control circuit 19 through the power supply circuit 25.
[0009]
The blower fan 26 is a fan that is driven when the dishes are washed and then dried.
[0010]
[Problems to be solved by the invention]
However, in such a conventional configuration, at least three contact detection circuits, that is, a power supply relay, a heater relay, and a safety switch, are necessary, and there is a problem in cost. Furthermore, since the circuit is complicated, it is a problem that a failure is likely to occur.
[0011]
The present invention solves the above-described conventional problems. By detecting the open / closed state of the contact of the power relay using the contact detection circuit of the safety switch, the safety is high and the maintenance is easy with a small number of contact detection circuits. It aims to realize a dishwasher.
[0012]
[Means for Solving the Problems]
For the present invention to achieve the above object, in dishwashers Kiyoshiinui燥機, a power supply relay for switching on and off the commercial power supply, and a cleaning tank for cleaning the dishes, jetting water by circulating the washing water in the cleaning tank A cleaning pump, a drain pump for draining the cleaning water in the cleaning tank to the outside of the machine, a heater for heating the cleaning tank, a lid for opening and closing the opening of the cleaning tank, and depending on opening and closing of the lid A safety switch that is turned on and off, a control circuit that drives the power relay, the washing pump , the drainage pump, the heater, and the like, and a safety switch that detects the open / closed state of the contact of the safety switch and sends a signal to the control circuit comprising a contact detection circuit, wherein with the safety switch are connected in series to the power relay, the drainage pump, in series connection between the power source relay and the safety switch at one end, before the other end By connecting to the control circuit, when the safety switch contacts detection circuit when the control circuit is not driving the power relay determines the contact of the safety switch closed, the control circuit the power source The relay is configured so as to notify the failure of the relay so that the operation can be stopped , and to determine which of the power relay and the safety switch has failed when the drain pump cannot be operated .
[0013]
As a result, even if there is no circuit that directly detects the contact state of the power relay, the open / close state of the power relay can be detected, and even if the relay breaks down, erroneous operation of unintended components is avoided. In addition, the failure location can be easily determined .
[0014]
DETAILED DESCRIPTION OF THE INVENTION
According to a first aspect of the present invention, in the tableware washing Kiyoshiinui燥機, and injection and supply relay for switching on and off the commercial power supply, and a cleaning tank for cleaning the dishes, the washing water in the cleaning tank circulation A washing pump for draining the washing water in the washing tank to the outside of the machine, a heater for heating the washing tank, a lid for opening and closing the opening of the washing tank, and depending on opening and closing of the lid A safety switch that is turned on and off, a control circuit that drives the power relay, the washing pump , the drainage pump, the heater, and the like, and a safety that detects the open / closed state of the contact of the safety switch and sends a signal to the control circuit a switch contact detection circuit, said safety the switch are connected in series to the power relay, the drainage pump, the series-connected portion of the one end and the safety switch and the power supply relay, the other end By connecting each of the control circuit, when the safety switch contacts detection circuit when the control circuit is not driving the power relay determines the contact of the safety switch closed, the control circuit the power source By notifying the failure of the relay, the operation can be stopped , and it is possible to determine which of the power relay and the safety switch has failed due to the inability to operate the drainage pump. Failure of the relay contact can be detected by the safety switch contact detection circuit, safety can be ensured, and it can be easily determined which of the power relay and the safety switch has failed .
[0015]
The invention according to claim 2 is the invention according to claim 1, wherein when the contact of the safety switch is opened, the power supply is stopped to the heater and the washing pump, so that even in the case of a failure of the control circuit, When the lid is opened, power supply to the heater and the cleaning pump can be stopped, and safety can be further secured.
[0016]
According to a third aspect of the present invention, in the first aspect of the present invention, when the safety switch contact detection circuit is open and the power supply relay is driven, the control circuit temporarily stops the heater and the cleaning pump. Therefore, when the lid is opened during operation or when the power supply relay is broken, the operation of the dishwasher is temporarily stopped to prevent the hot water from popping out. It can be realized at low cost.
[0017]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0018]
Example 1
1 and 2 are block diagrams of a circuit of the dishwasher / dryer of the present invention. Note that the same components as those in the conventional example are denoted by the same reference numerals and description thereof is omitted.
[0019]
As shown in FIGS. 1 and 2, the commercial power supply 15 supplies power to the control circuit 27 via the power supply circuit 25, and also includes a power supply relay 16 driven by the control circuit 27, a heater 8, a cleaning pump 9, AC power is supplied to the pump 12, the water supply valve 13, the blower fan 26, and the like.
[0020]
The safety switch 28 that is turned on and off according to the opening and closing of the lid 3 that opens and closes the cleaning tank 1 is connected to the power supply relay 16 in series and includes a safety switch contact detection circuit 29 that detects the contact state. The safety switch contact detection circuit 29 is configured as shown in FIG. In FIG. 2, when the safety switch 28 is closed, the voltage from the commercial power supply 15 is converted into a DC voltage by the rectifier circuit 30, and a High signal is output to the control circuit 27. In addition, when the safety switch 28 is in an open state, a Low signal is output to the control circuit 27.
[0021]
In FIG. 1, the power relay 16 is driven by pressing a power switch of the input means 24 connected to the control circuit 27. The power supply relay 16 turns on and off the power supply from the commercial power supply 15 to the heater 8, the washing pump 9, the drainage pump 12, the water supply valve 13, the blower fan 26, and the like. Further, the safety switch 28 turns on and off each load except the drain pump 12 according to the opening and closing of the lid 3. The drainage pump 12 is configured to be able to drain the water in the cleaning tank even when the lid 3 is opened, and can cope with a failure or the like.
[0022]
The power relay 16 and the safety switch 17 are connected in series. In such a configuration, when the control circuit 27 is not driving the power supply relay 16, the output of the safety switch contact detection circuit 29 of the safety switch 28 should be Low. However, in this case, when the output of the safety switch contact detection circuit 29 detects the High signal, it can be determined that the contact of the power supply relay 16 is short-circuited and is different from the signal of the control circuit 27. In such a state, it is determined that the power relay is short-circuited, and the control circuit 27 stops the operation of the device and displays an abnormality such as a blinking lamp on the display means 23 in order to alert the user to the failure. Warning with a sound such as a buzzer.
[0023]
When the lid 3 is open, the safety switch 28 is in an open state, so that a short circuit failure of the power relay 16 is not detected by the safety switch contact detection circuit 29, but the safety switch 28 is connected in series with the power relay 16. Therefore, safety is ensured because power is not supplied to the load.
[0024]
As described above, the short circuit failure of the power relay 16 is detected by using the safety switch contact detection circuit 29 of the safety switch 28 that detects the open / closed state of the lid 3, so that the power relay contact detection circuit of the power relay 16 is unnecessary. Therefore, an inexpensive and highly safe dishwasher can be realized.
[0025]
(Example 2)
As shown in FIG. 1, when the contact of the safety switch 16 is opened, the heater 8, the cleaning pump 9, and the commercial power supply 15 are disconnected, and the power supply is stopped. In such a configuration, when the lid 3 is opened, the heater 8 and the cleaning pump 9 are stopped in response to a signal from the control circuit 27, so that the user is protected from the hot water for cleaning and the burns caused by the heat of the heater 8. can do. Therefore, the power relay contact detection circuit for the power relay 16 is not required, and even if the control circuit 27 is out of order, the power supply to the heater 8 can be stopped if the lid 3 is opened during operation, so that it is cheaper and safer. A highly functional dishwasher can be realized.
[0026]
(Example 3)
In FIG. 1, when the power relay 16 is driven and the lid 3 is closed, the safety switch 28 is closed, so the safety switch contact detection circuit 29 shows a closed state. In this case, the device is in a normal operating state.
[0027]
On the other hand, when the power supply relay 16 is not driven, the safety switch contact detection circuit 29 shows an open state because the safety switch 28 is open regardless of whether the lid 3 is closed or open. In this state, the open / closed state of the lid 3 cannot be detected by the control circuit 27. However, since the power relay 16 is not driven, the device is not operated and there is no problem.
[0028]
When the power relay 16 is being driven and the safety switch contact detection circuit 29 is in an open state, the contact of the power relay is in an open failure, the contact of the safety switch 28 is in an open failure, or the lid 3 is This is a case where the safety switch 28 is opened and opened.
[0029]
In the embodiment of the present invention, in this case, since it is not possible to determine whether the lid 3 is open or the device is faulty, at least the heater 8 and the cleaning pump 9 are temporarily stopped to ensure safety. If the lid 3 is open, the user can resume the operation by closing the lid 3.
[0030]
Further, when the operation cannot be performed with the lid 3 closed, it is considered that the power relay 16 or the safety switch 28 is broken. In the embodiment of the present invention, the drain pump 12 can be operated in a state in which the drain pump 12 can be operated with the safety switch 28 opened. For this reason, in this embodiment, by incorporating a control program in a mode in which the drainage pump 12 is operated with the lid 3 opened, if the drainage pump 12 can be operated, it can be determined that the contact failure of the safety switch 28 has occurred, If the drainage pump 12 cannot be operated, it can be determined that the contact failure of the power relay 16 has occurred, so that the maintenance of the equipment becomes easy.
[0031]
Therefore, as described above, the power relay contact detection circuit of the power relay 16 is not necessary, and even when the lid 3 is opened during the operation or the power relay is broken open, the operation of the device is temporarily stopped, Since popping out can be prevented, a dishwasher / dryer that is inexpensive, highly safe, and easy to use can be realized.
[0032]
【The invention's effect】
As described above, according to the first, second, and third aspects of the present invention, even if there is no circuit for directly detecting the contact state of the power relay, the open / close state of the power relay can be detected. Even if the relay breaks down, it is possible to avoid erroneous operation of unintended components and to easily determine the location of the failure, so an inexpensive dishwasher that is safe and easy to maintain Can be realized.
[Brief description of the drawings]
FIG. 1 is a block diagram of a control circuit of a dishwasher / dryer according to an embodiment of the present invention. FIG. 2 is a circuit diagram of a contact detection circuit of the dishwasher / dryer. [Figure 4] Block diagram of the control circuit of the dishwasher [Explanation of symbols]
1 Washing tank 3 Lid 8 Heater 9 Washing pump
12 Drain pump 15 Commercial power supply 16 Power relay 27 Control circuit 28 Safety switch 29 Safety switch contact detection circuit

Claims (3)

A power supply relay for turning on and off the commercial power supply, a washing tank for washing dishes, a washing pump for injecting and circulating washing water in the washing tank, and a drainage pump for draining the washing water in the washing tank to the outside of the machine When a heater for heating the cleaning tank, said a lid for opening and closing the opening of the cleaning tank, and a safety switch that is turning on and off in response to the opening and closing of the lid, the power supply relay, the washing pump, the drain pump and A control circuit that drives the heater and the like, and a safety switch contact detection circuit that detects a switching state of the contact of the safety switch and sends a signal to the control circuit, and the safety switch is connected in series to the power relay , the drainage pump, in series connection between the power source relay and the safety switch at one end and connecting, respectively the other end to said control circuit, said control circuit the power source When the safety switch contact point detecting circuit when not driving the laser determines the contact of the safety switch closed, together with the control circuit notifies the failure of the power supply relay is configured to stop the operation the tableware washing Kiyoshiinui燥機receive one determines configured to enable or has failed the safety switch and the power supply relay by possible non operation of the drainage pump.   The dishwasher / dryer according to claim 1, wherein when the contact of the safety switch is opened, the power supply to the heater and the washing pump is stopped.   2. The dishwasher / dryer according to claim 1, wherein when the safety switch contact detection circuit is in an open state and the power supply relay is driven, the control circuit temporarily stops the heater and the washing pump.

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