JPS60169901A - Control circuit - Google Patents

Abstract

PURPOSE:To interrupt current supply to a load safely and precisely by interrupting the load directly at an interruption part and transmitting the interruption to a sequential operation control through a level conversion part to control the load. CONSTITUTION:A control part controlling the load 12 is a two-way semiconductor switching element and the load 12 is a motor of a washing machine. The loading circuit is provided with the interruption part 3 consisting of a switch interlocking with a cover to interrupt the load 12 directly. An output from the interruption part is inputted to the sequential operation control part 5 through the level converter 4. The control part 5 is constituted by a microcomputer or the like to stop the sequence operation of the washing machine on the basis of the input signal from said conversion part 4 and to control the control part 11 s as to turn the part 11 disconnected state.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a control circuit for household electrical appliances, such as washing machines, dishwashers, dryers, etc.

Conventional configuration and its problems Conventionally, for example, when opening and closing the lid of a washing machine, if the operation is to be stopped, a switch is provided that is linked to the lid, and the switch operation is input to the sequential operation control section. According to the instructions of
A common configuration has been to stop power supply to a load (for example, a motor).

However, since the control is performed via a sequential operation control section, fail-safe control is not necessarily achieved, which poses a problem.

OBJECT OF THE INVENTION The present invention aims to solve this problem at low cost.

Structure of the Invention In order to achieve the above object, the control circuit of the present invention includes a load, a control section that controls the load, a cutoff section that is connected to the load and forcibly cuts off power to the load, and a control circuit that is connected to the cutoff section and cut off. and a sequential operation control section that takes the output of the level conversion section as input and controls the control section. The fact that the load has been cut off is transmitted to the sequential operation control section via the conversion section, and the sequential operation control section controls the load.

Description of examples The present invention will be explained in detail with reference to FIG.

Reference numeral 1 denotes a control section for controlling the load, which is composed of, for example, a bidirectional semiconductor switching element. Reference numeral 2 denotes a load such as a motor, numeral 3 a cut-off section consisting of, for example, a switch interlocked with a lid, and numeral 4 a level conversion section for converting the level of the output of the cut-off section 3, which is composed of, for example, a transistor. Reference numeral 5 denotes a sequential operation control section composed of a microcomputer or the like.

For example, a cutoff section 3 consisting of a switch directly cuts off the load 2 and inputs the output from the cutoff section 3 to the sequential operation control section 5 via the level conversion section 4 to ensure that the load 2 is cut off. , and transmits the shut-off state of the shut-off section 3 to the sequential operation control section 5.

An embodiment in which the present invention is applied to a washing machine will be described with reference to FIG.

Reference numeral 11 denotes a bidirectional switching element which serves as a control unit and controls a load, and controls a motor 12 as a load. Reference numeral 13 designates a switch interlocked with the lid as a shut-off part, and is in contact with the d side when the lid is closed. Now, when the lid is opened, the switch 13 contacts the b side, and the power to the motor 12 is cut off. on the other hand,
Since the switch 13 is in contact with the b side, the commercial power supply 1
A voltage of 0 is applied to the level converter 4. That is, the voltage of the commercial power supply 10 is applied to the transistor 44 via the resistors 41 and 42 constituting the level converter 4, thereby rendering the transistor 44 conductive. 43 is a protection diode for the transistor. When the transistor 44 becomes conductive, the transistor 47 is made conductive through the resistors 45 and 46, and the signal is input to the sequential operation control section 5 through the resistor 48. The sequential operation control section 6 is composed of, for example, a microcomputer, and controls the sequence of the washing operation and the load.The sequential operation control section 6 stops the sequential operation according to the input signal, and also controls the washing operation sequence. transistor 7,
The bidirectional semiconductor switching element 1 via a resistor 8
1 is controlled to be non-conductive. Reference numeral 9 denotes a DC power supply that is supplied to the bidirectional semiconductor switching element 11, the level conversion section 4, and the sequential operation control section 6.

Effects of the Invention As described above, according to the present invention, when cutting off power to a load, especially a load connected to a commercial power source, and stopping the progress of sequential operations, it is possible to safely and reliably apply power to the load. The power supply can be cut off and the operation can be stopped sequentially at the same time, which is very effective.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a control circuit showing one embodiment of the present invention, and FIG. 2 is a circuit diagram showing a specific configuration of the control circuit. 1...Control unit, 2...Load, 3...
. . . Cutoff section, 4. . . Level conversion section, 6. . . Sequential operation control section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Claims] A load, a control section that controls the load, a cutoff section that is connected to the load and forcibly cuts off current to the load, a level conversion section that is connected to the cutoff section and converts the level of the output of the cutoff section, and this level conversion. A control circuit comprising a sequential operation control section that controls the control section using an output of the section as an input.