JPS63105798A - Washing machine - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a washing machine equipped with a water level switch that responds to the water level in a washing tub.

(Prior Art) A conventional water supply control system for this type of washing machine was as follows. First, the water level switch has a diaphragm that displaces according to the head of water stored in the washing tub, and drives a contact based on the displacement of this diaphragm, so that the water level in the washing tub reaches a predetermined amount. The structure is such that, when the power level increases, the pair of contacts is reversed from OFF to ON, for example. When the water supply control circuit connected to this water level switch via a connector etc. receives a command to start water supply, the water supply valve is opened to supply water to the washing tub, provided that the contact pair of the water level switch is in the OFF state. water supply is started, and when a signal indicating that the contact pair is turned on is received, the water supply valve is closed and the water supply is stopped.

(Problem to be Solved by the Invention) However, in this type of configuration, if an abnormality occurs in the peripheral circuit of the water level switch, such as a poor connection in the connector that connects the water level switch and the water supply control circuit, the washing tub Even if the water level in the tank rises above a predetermined level, the ON signal from the water level switch will no longer be input to the water supply control circuit. However, in the conventional configuration described above, the water supply valve is opened on the condition that there is no on signal from the water level switch, and the water supply valve is closed when the on signal is received, so the above-mentioned abnormality occurs. The water supply operation continued without the water supply valve becoming blocked. This not only wastes water, but also sometimes causes problems such as water overflowing from the washing machine onto the floor.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a washing machine that can stop the water supply operation even if an abnormality occurs in the peripheral circuit of the water level switch, thereby preventing wastage of water.

[Structure of the Invention] (Means for Solving the Problems) The washing machine of the present invention switches the water level switch from one contact to the other when the water level in the washing tub rises above a predetermined level. It is characterized in that it is constructed of a switching type, and is provided with a water supply control means that stops the water supply operation when it is not detected that either of the two contacts is in the on state.

(Function) If a circuit abnormality occurs around the water level switch due to a poor connection in the connector connected to the water level switch, it will not be detected that either of the contacts on both sides of the water level switch are in the on state, so the water supply control means The water supply operation is stopped.

(Example) Hereinafter, an example in which the present invention is applied to a microcomputer-controlled P-type dehydrating washing machine will be described with reference to the drawings.

Reference numeral 1 denotes a motor that selectively drives a rotating tub (not shown) corresponding to a washing tub and an agitator provided at the inner bottom thereof, and this motor is connected to an AC power source 4 via first and second triacs 2 and 3. , by selectively turning on each triac 2.3, forward and reverse rotation is possible. 5 is a water supply valve for supplying water into the rotating tank, and 6 is a drain valve for draining water from the rotating tank, and these are connected to the AC power source 4 via the third and fourth triacs 7 and 8, respectively. ing.

Each of the triacs 2, 3° 7.8 described above is connected to the output interface 1 by the microcomputer 9.
0, and each process such as washing, rinsing, and dehydration is executed. That is, in a fully automatic course in which the above-mentioned steps are executed in series as shown in FIG. 3, for example, the water supply valve 5 is first opened to perform a water supply operation to supply water to the washing tub. When the inside of the washing tub reaches a predetermined water level, the water supply operation is stopped based on the operation of the water level switch 11, which will be described later, and a washing process is performed in which the motor 2 repeats forward and reverse rotation at a predetermined period.After this, the drain valve 6 is opened to perform a drainage operation to drain water from the washing tank. Next, a dehydration process is performed in which the motor 2 is driven to rotate the rotary tank at high speed, after which water is supplied again, a predetermined number of rinsing processes are performed, and after draining, a dehydration process is performed. .

Now, 11 is a water level switch that responds to the water level in the rotating tank, and this has a diaphragm of a well-known configuration that is displaced according to the head of water stored in the rotating tank, and the switch is activated based on the displacement of the diaphragm. The elements have a different configuration from conventional water level switches. That is, this water level switch 11 has a common contact COM, a normally open contact No., and a normally closed contact N.
When the water level in the rotating tank is below a predetermined level, the common contact COM and the normally closed contact NC are in the on state, and when the water level rises above the predetermined level, the common contact CO
The connection between M and normally closed contact NC turns off, and the common contact CO
The contact between M and normally open contact No. is switched on. Each contact point of this water level switch 11 is connected to an input interface 13 via a connector 12, so that the switching state of the water level switch 11 is inputted to the microcomputer 9. The microcomputer 9 also functions as water supply control means, and is programmed to execute the water supply operation described above according to the water supply routine shown in the flowchart of FIG.

Next, the operation of this embodiment will be explained, focusing on the water supply operation that is directly related to the present invention. This should make the functional configuration of the microcomputer 9 more clear.

When a power switch (not shown) is turned on and a command to execute the washing process is given to the microcomputer-9, the microcomputer-9 first turns on the normally closed contact NC of the water level switch 11 (between the common contact COM and the normally closed contact N0). (determination step a in Fig. 2).

Here, when "YesJ" is obtained, the water level in the rotating tank is below a predetermined level, so the water supply valve 5 is energized and water supply to the rotating tank is started, and the result of this judgment step a is "YesJ".
This state will continue as long as. Then, due to such water supply, the water level in the rotating tank rises by "2", and when this reaches a predetermined amount "2", the normally closed contact NC of the water level switch 11 is turned off (common contact COM - normally closed contact NC is opened). Since the judgment step a becomes rNoJ, the water supply valve 5 is cut off and the water supply operation is stopped. After this, in judgment step b,
It is determined whether the normally open contact NO of the water level switch 11 is in the ON state B (open between the common contact COM and the normally open contact NO), but the water level switch 11 is a switching type and the normally closed contact NC
If it turns off, the normally open contact No. turns on, so as long as the peripheral circuit of the water level switch 11 is normal, the result of the second judgment step b will be rYesJ, and then the predetermined washing process time will be set in the microcomputer-9. Set. Then, the washing process is executed for the set time, and a series of processes as described above are further executed.

Here, if there is an abnormality such as poor contact between the connector 12 between the water level switch 11 and the input interface 13, the microcomputer 9 will not be able to receive a signal from the water level switch 11. However, in this embodiment, when it is not detected that either the normally closed contact NC or the normally open contact NO of the water level switch 11 is in the on state, as shown in FIG. Together, they became rNoJ and “
Since the water supply operation is stopped by this, the water supply valve 5 is kept open forever, wasting water, and sometimes water overflowing from the washing machine. This can be reliably prevented. In this case, normally open contact N.

When a contact failure occurs only in the signal line from When the normally closed contact NC is turned off, judgment step b becomes rNoJ, and at that stage, the operation is stopped. In addition, when a contact failure occurs in the signal line of the common contact COM or the normally closed contact NC, it is not detected that the normally closed contact NC is in the on state, and both judgment steps a and b immediately become rNoJ. The water supply operation is not performed and the operation is stopped.
It is clear that the water supply operation is reliably stopped even if there is a contact failure in any of the three signal lines. In addition, if an abnormality occurs not only in the connector 12 but also in any part of the peripheral circuit from the water level switch 11 to the microcomputer 9, either the normally closed or normally open contacts NC or No are in the ON state. Even when it is no longer detected, the water supply operation is no longer performed in the same manner as described above.

Although the above embodiment shows an example in which the water supply operation is performed by opening the water supply valve 5, the present invention is not limited to this, and can also be applied to a washing machine that performs the water supply operation by driving a water supply pump. In addition, the present invention is not limited to the embodiments described above and shown in the drawings, but may be applied in various ways without departing from the scope of the invention, such as being applied to a so-called two-tub washing machine that is equipped with a washing tub and a dehydrating tub. It is something that can be modified and implemented.

[Effects of the Invention] As described above, the present invention comprises a water level switch of a switching type, and includes water supply control means that stops the water supply operation when it is not detected that either of the contacts is in the on state. As a result, even if there is an abnormality in the water level switch or its surrounding circuits, the water supply operation is reliably stopped, preventing accidents such as water being wasted or the washing machine overflowing. This has the excellent effect of preventing

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a circuit diagram, and FIG. 2 is a circuit diagram.
The figure is a flowchart of the water supply routine, and FIG. 3 is a time chart 1 showing the relationship between each stroke and the on/off state of the water level switch. In the drawing, 5 is a water supply valve, 6 is a drain valve, 9 is a microcomputer (water supply control means), 11 is a water level switch, 12
is a connector.

Claims (1)

[Claims] 1. A water level switch is provided that responds to the water level in the washing tub, and when the water level in the washing tub is below a predetermined level, the water supply operation is performed, and when the water level rises above the predetermined level, the water supply operation is stopped based on the operation of the water level switch. In the water level switch, the water level switch is of a switching type that switches from one contact to the other contact when the water level in the washing tub rises above a predetermined level, and both contacts are switched on. 1. A washing machine comprising a water supply control means that stops water supply operation when it is not detected that any one of them is in an on state.