JPH04105695A - Washing machine - Google Patents

Abstract

PURPOSE:To achieve low cost and to prevent an abnormal operation by applying the operation of a load equipment to a second microcomputer by a first microcomputer and control command to a driving circuit by the second microcomputer and stopping the operation when the output logical values of the output ports of the two computers are different. CONSTITUTION:In an operation, operation commands for driving and stopping a motor 3 and data such as normal rotation and opposite rotation and rotating speed of the motor 3 are transferred to a sub-microcomputer 7 from a host microcomputer 6. The sub-microcomputer transmits the control commands for driving and stopping, normal rotation and opposite rotation of the motor 3 and a voltage control command to a motor driving circuit 12. Only when a signal of L level, namely, an operation command is output from both output ports F and A of the sub-microcomputer 7 and the host microcomputer 6, an output S reaches H level to operate the motor 3. On the other hand, when a signal of H level is output from one of them, the motor 3 is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Industrial Application Field) The present invention relates to a washing machine in which the operation of each load device is controlled by, for example, two microcomputers.

(Prior art) For example, a washing machine with a dehydrating function is equipped with an operation control circuit including a microcomputer, and based on the operation of the microcomputer, various load devices such as a washing machine motor are controlled to perform washing. It is designed to perform driving. In this case, one microcomputer is usually provided.

Incidentally, the cost of the one-chip microcomputer used in this type of washing machine increases progressively as the number of terminals and memory capacity increases. Therefore, in recent years, attempts have been made to reduce costs by using a configuration using a plurality of microcomputers, for example, two microcomputers. In this case, the host microcomputer controls some load devices (for example, display devices, valve devices, etc.) and outputs operation commands to the sub-microcomputer, and the sub-microcomputer or the host microcomputer responds to the operation commands. The aim is to control the remaining load equipment (washing machine motor) based on this.

(Problem to be Solved by the Invention) However, as described above, when the operation of the washing machine motor is controlled by a sub-microcomputer, if this sub-microcomputer goes out of control, the host microcomputer will control the operation of the washing machine motor. Even when no operation command is given for the operation of the washing machine, the washing machine motor continues to operate and the host microcomputer is unable to stop the washing machine, which may lead to a dangerous situation.

The present invention has been made in view of the above circumstances, and its purpose is to provide a washing machine that can reduce costs by using a plurality of microcomputers and that can prevent abnormal operation of load equipment. is to provide.

[Structure of the Invention] (Means for Solving the Problems) A washing machine of the present invention includes a first microcomputer, a second microcomputer, and a drive circuit that drives a load device such as a washing machine motor. , the first microcomputer gives an operation command to operate the load equipment from its predetermined output port to the second microcomputer, and based on this command, the second microcomputer starts operating the load equipment from the predetermined output port. The control command is given to the drive circuit to control the operation of the load equipment when the output logic value of the output port of the first microcomputer differs from the output logic value of the second microcomputer. This is characterized by the provision of a means for prohibiting operation to stop the operation.

(Function) According to the above means, the load equipment such as the washing machine motor
It is operated via a drive circuit according to control commands from a predetermined output port of the microcomputer. in this case,
The control command from the second microcomputer is output based on the operation command from a predetermined output port of the first microcomputer, and the control command is output based on the operation command from a predetermined output port of the first microcomputer. When the output logic value of the second microcomputer is different, the operation of the load equipment is stopped by the operation prohibition means. Therefore,
Even if the second microcomputer goes out of control and continues to issue control commands to operate the load equipment, if the first microcomputer is not outputting operation commands for the load equipment, it will not be possible to operate the load equipment. is stopped, thereby preventing abnormal operation of the load equipment.

(Example) An example in which the present invention is applied to a dehydrating and washing machine will be described below with reference to the drawings.

FIG. 1 schematically shows the electrical configuration of a washing machine according to this embodiment. Although not shown in detail, inside the outer box of the washing machine, there is provided a rotating tub in which the laundry is stored, as well as a water supply valve 1 that supplies water to the tub and a drain valve that drains water from the tub. 2 is provided. An agitator for generating washing water flow is provided in the tank, and during washing, this agitator is rotated by a washing machine motor 3 serving as a load device, and during dewatering, the washing machine motor 3 stirs the tank and the agitator. The body is designed to rotate as a unit. Moreover, various switches 4 such as a selection switch and a start switch for the user to select a desired washing course are provided at the top of the outer box, and a display section 5 is also provided.

6 is a host microcomputer which is a first microcomputer, and 7 is a sub microcomputer which is a second microcomputer. Among these, the host microcomputer 6 is configured to receive signals from the various switches 4, as well as a lid switch 8 for detecting opening/closing of a lid provided on the top surface of the outer box and the rotating tank. A detection signal from a water level sensor 9 that detects the water level inside the tank is input. Based on these inputs, the host microcomputer 6 controls the buzzer 10 that generates a sound or warning sound and the display unit 5 according to a program stored in advance. The water supply valve 1 and the drain valve 2 are controlled by the water supply valve 1 and the drain valve 2. Further, the host microcomputer 6 is configured to give an operation command for operating the motor 3 to the sub-microcomputer 7, as will be described later. The sub microcomputer 7 is the host microcomputer 6
A control command is given to a motor drive circuit 12 that drives the motor 3 based on the operation command. The motor drive circuit 12 is composed of an inverter circuit, and is configured to drive and stop the motor 3, as well as control forward and reverse rotation, and voltage applied to the motor 3 (rotation speed).

In this case, as shown in FIG. 2, the host microcomputer 6 and sub-microcomputer 7 are connected by five signal lines 13 to 17. this house,
An operation command for operating the motor 3 is outputted from a predetermined output port A of the host microcomputer 6 and given to the sub-microcomputer 7 via a signal line 13. Further, a transfer timing instruction signal is sent from the signal line 14, and a data transfer timing clock signal is sent from the signal line 15, respectively, to the host microcomputer 6.
The submicrocomputer 7 is provided with the submicrocomputer 7 from the submicrocomputer 7. Further, the signal lines 16 and 17 are serial data signal lines, and the signal line 16 is connected from the host microcomputer 6 to the sub-microcomputer 7.
For example, serial 8-bit data transfer is performed from the sub-microcomputer 7 to the host microcomputer 6.

Further, the sub-microcomputer 7 and the motor drive circuit 12 are connected by three signal lines 18 to 20 in this case. Here, a control command for controlling the drive/stop of the motor 3 is output from a predetermined output port F of the sub-microcomputer and is given to the motor drive circuit 12 via a signal line 18.1. Further, forward/reverse rotation control commands and voltage (rotational speed of the motor 3) control commands are given to the motor drive circuit 12 through signal lines 19 and 20, respectively. As a result, the operation of the washing machine motor 3 is controlled via the sub-microcomputer 7 and the motor drive circuit 12 in accordance with the program of the host microcomputer 6, and thus the washing machine motor 3 is controlled in accordance with the program of the host microcomputer 6. It is designed to execute a predetermined washing operation depending on the function.

Now, the motor drive circuit 12 is configured to include a gate circuit 21 as an operation inhibiting means according to the present invention. As shown in FIG. 2, this gate circuit 21 consists of a so-called NOR circuit equipped with two transistors 22 and 23, and is connected to the output port F of the sub-microcomputer 7.
A signal from the host microcomputer 6 is input to the base of the transistor 22 via a signal line 18, and a signal from the output port A of the host microcomputer 6 is input to the base of the transistor 23 via a signal line 24 branched from the signal line 13. It is now possible to do so. In this case, when the motor 3 is to be operated, L level signals are output from the output port F and the output port A, respectively, and the motor drive circuit 12 outputs an L level signal from the output port F and the output port A, respectively. The motor 3 is configured to operate when S is at H level and to be stopped when S is at L level.

Therefore, as shown in FIG. 3, when L level signals are being output from both the output port F of the sub-microcomputer 7 and the output port A of the host microcomputer 6 (between T+ and T2), Only when the output S becomes H level, the motor 3 is operated.

With this, the gate circuit 21 causes the operation of the motor 3 to be stopped when the output logic value of the output port A of the host microcomputer 6 differs from the output logic value of the output port F of the sub-microcomputer 7. It has become.

Next, the operation of the above configuration will be described.

When the washing operation is started, the motor 3 is rotated in forward and reverse directions repeatedly, and the stirring body is rotated in the forward and reverse directions to generate a washing water flow in the tub. Further, during the spin-drying operation, the rotation of the motor 3 rotates the tub containing the laundry. In this case, motor 3 is
Is the operation performed according to a program stored in the host microcomputer 6 in response to inputs from various switches 4?
Data on forward rotation, reverse rotation, and the number of revolutions of the motor 3 are transferred to the sub-microcomputer 7, and based on the data, the sub-microcomputer 7 issues control commands for driving and stopping the motor 3 to the motor drive circuit 12, as well as forward and reverse rotation control. This is done by giving commands and voltage (rotational speed of motor 3) control commands. Here, as mentioned above, motor 3
The driving and stopping of the motor is performed by the gate circuit 21 of the motor drive circuit 12.
This is done based on both the control command given from the sub-microcomputer 7 and the operation command output from the host microcomputer 6. That is, when an L level signal, that is, a command to operate, is being output from both the output port F of the sub-microcomputer and the output port A of the host microcomputer 6 (between T and T2 in FIG. 3). ), the motor 3 is operated with the output S or H level, and when either the output port F of the sub-microcomputer 7 or the output port A of the host microcomputer 6 becomes H level, the output becomes S or L level. The motor 3 is then stopped.

Therefore, if the sub-microcomputer 7 goes out of control, the control command can continue to be output from the output port F of the sub-microcomputer 7 to the motor drive circuit 12 even when no operation command is given from the host microcomputer 6. Yes (between T2 and T in Figure 3). However, in this case, the gate circuit 21 causes the motor 3 to
operation will be stopped. With this, even if the sub-microcomputer 7 goes out of control, abnormal operation of the motor 3 can be prevented and a dangerous situation can be avoided.

As described above, according to this embodiment, the configuration includes two microcomputers 6.7, and the host microcomputer 6 controls some of the load devices (the display 5, the valve device 1.
2, etc.) and outputs operation commands to the sub-microcomputer 7, which then controls the remaining load equipment (washing machine motor 3), which requires a large number of terminals and memory capacity, making it expensive. It is possible to reduce costs by not using a large microcomputer.

In addition, since we have provided the gate circuit 21 as a means of prohibiting operation, in the unlikely event that the sub-microcombination unit goes out of control, as previously thought, the washing machine motor will continue to operate, resulting in a dangerous situation. Unlike the case where there is a risk of damage, even if the sub-microcomputer 7 goes out of control, the operation of the washing machine motor 3 can be stopped, abnormal operation can be prevented, and a dangerous situation can be avoided. It is something.

In the above embodiment, the washing machine motor 3 is used as a load device.
Although only the water supply valve 1 and the drain valve 2 may be configured to be controlled by the sub-microcomputer 7, the present invention can be modified without departing from the scope of the invention. It can be implemented with appropriate changes.

[Effects of the Invention] As is clear from the above description, the washing machine of the present invention includes a first microcomputer, a second microcomputer, and a drive circuit that drives a load device such as a washing machine motor. The first microcomputer gives the second microcomputer an operation command to operate the load equipment from its predetermined output port, and the second microcomputer gives an operation command from the predetermined output port based on this command. This system is designed to give control commands for operating load equipment to the drive circuit, and when the output logic value of the output port of the first microcombicoater differs from the output logic value of the second microcomputer, the load Since an operation prohibition means is provided to stop the operation of the equipment, costs can be reduced by using multiple microcomputers, and it is possible to prevent abnormal operation of the load equipment and prevent dangerous situations. This has the excellent effect of being able to be avoided.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention. Figure 1 is a block diagram showing the overall electrical configuration, Figure 2 is a diagram showing the electrical configuration of the main parts, and Figure 3 is a diagram showing the input and output of the gate circuit. FIG. 3 is a diagram showing the relationship with output. In the drawing, 3 is a washing machine motor (load equipment), 6 is a host microcomputer (first microcomputer),
7 is a sub-microcomputer (second microcomputer), 12 is a motor drive circuit (drive circuit), 21 is a gate circuit (driving ticket stopping means), and A and F are output ports. Agent Patent Attorney Tsuyoshi SatoFigure 1

Claims (1)

[Claims] 1. A first microcomputer, a second microcomputer, and a drive circuit that drives a load device such as a washing machine motor, and the first microcomputer drives the load device from its predetermined output port. The second microcomputer is configured to give a command for the operation to be performed to the second microcomputer, and based on this command, the second microcomputer gives a control command for operating the load equipment to the drive circuit from a predetermined output port. Yes, the first
1. A washing machine comprising operation prohibition means for stopping the operation of said load device when an output logical value of an output port of said microcomputer differs from an output logical value of said second microcomputer.