JPH0325213A - Control device for fan forced heater - Google Patents

Abstract

PURPOSE:To ensure safety during malfunction of a microcomputer by a method wherein when an air purifying means is brought into an operation state and a heating means is brought into a inoperative state, the microcomputer releases a self-holding means. CONSTITUTION:A parallel circuit is formed with a coil 3a of a relay 3 for driving an air purifying means 6 and a contact 10b of a relay 10 for a self- holding circuit. Operation of a heating means 4 is stopped. When only the air purifying means 6 is operated, a relay 2 for drive is brought into an OFF-state, a contact 2b is brought into an ON-state, and an output signal D is brought into an L-state by means of an output signal B from a microcomputer 1. This operation brings a transistor 9 into an OFF-state, brings a relay 10 for a self- holding circuit into an OFF-state, and brings the contact 10b into an opening state. A manual switch 7 is formed with a switch which is kept at an ON-state only during operation and at an OFF-state during inoperation. The relay 10 for a self-holding circuit is kept at an OFF-state. This constitution enables provision of a control device which prevents the heating means 4 from being brought into an operation state even when the microcomputer 1 effects malfunction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for a hot air heater equipped with an air purifying means.

[Conventional technology]

FIG. 2 is a control circuit diagram of a conventional hot air heater of this type.

In FIG. 2, 1 is a microcomputer as a control means, 2 is a relay for driving a heating means consisting of a coil 2a and a contact 2b, and 3 is a relay 1/4 for driving an air purifying means consisting of a coil 3a and a contact 3b. is a heating means, 6 is an electrostatic precipitator type air purifying means, 7 is a manual switch, A is a group of signals input to the microcomputer 1, B, C, and D are each output signal from the microcomputer 1, and 9 is an output Transistor turned on by signal A, 10 is coil 10a and contact 1
A self-holding circuit relay 11 is a self-holding circuit DC power supply, and 12 is a switching means that is operated when the air purifying stage 6 is operated independently.

Here, the driving relay 2 of the heating means 4 and the air purifying means 6
Each coil 2^p3a of the drive relay 3 is connected in series with the contact 10b of the self-holding circuit relay 10, and its operation is controlled by the output signal B and output signal C from the microcomputer 1, respectively. It looks like this.

Next, the operation will be explained. When the manual switch 7 is turned on, if the output signal D of the microcomputer is rHJ, the transistor 9 is turned on, current flows through the coil 10a of the self-holding circuit relay 10, and its contact 10b closes, turning it on. After that, even if the manual switch 7 is opened, the self-holding circuit relay 10 maintains the self-holding state. When this self-holding road relay 10 is in the ON state, the microcomputer receives the signal group A indicating the indoor temperature, combustion state, etc., and outputs the output signal B accordingly. It is turned off to open and close the contact 2b to control the operation of the heating means 4.

In addition, when operating the air purifying means 6 at the same time as heating,
The drive relay 3 is turned on and off by the output signal C to open and close the contact 3b, and the electric dust collecting type air purifying means 8 is energized.

On the other hand, when operating the switch means 12 to stop the operation of the heating means 4 and only operate the air purifying means 8, the output signal B causes WX! Turn off Il relay 2 and close contact 2b.
is opened to stop the operation of the heating means 4 such as combustion, the drive relay 3 is turned on by the output signal C, and the contact 3be is closed to energize the air purifying means 6.

[Problem to be solved by the invention]

However, in this state, if the microcomputer 1 malfunctions due to noise, f, etc., the output signal B is output, the drive relay 2 is turned on, the contact 2b is closed, and the heating means 4 such as combustion is energized. There was a safety problem because the heating means 4 started heating at M@ and started heating on its own.

This invention has been made to solve the above-mentioned problem, and even if the microcomputer malfunctions when the air purifying means is in operation and the air purifying means is in non-operation state, o! It is an object of the present invention to provide a control device in which a cell means does not go into operation.

[Means to solve the problem]

Warm air I according to this invention! ! The control device for the air conditioning unit includes an air purifying means, a heating means, a self-holding means, and a microcomputer that controls each of these means, in which the operation of the heating means is restricted by the self-holding means, The means is configured such that its operation is not restricted by the self-holding means, and the microphone a computer releases the self-holding means when the air purifying means is in an operating state and the heating means is in a non-operating state.

[Effect]

In this invention, the self-holding circuit can restrict the operation of the special cell means, and when the special cell means is in a non-operating state, the self-holding circuit is activated. ! remove.

〔Example〕

FIG. 1 is a schematic diagram of an embodiment of the present invention.

In Fig. 3, the same reference numerals as in Fig. 2 indicate wet parts.
The difference from Figure 2 is '9! The coil 3a of the drive relay 3 of the air purifying means 6 is connected to the contact 10 of the self-holding circuit relay 10.
The point is that it is connected to form a parallel circuit with b.

Now, when the manual switch 7 is turned on, if the output signal D of the microcomputer 1 is in the rHJ state, the transistor 9 is turned on, current flows through the coil 10a of the self-holding circuit relay 10, and the contact 10b is closed. After being turned on, even if the manual switch 7 is released, the self-holding circuit relay 10 maintains the self-holding state. When this self-holding circuit relay 10 is in the on state, the microcomputer 1 receives a group of signals A such as indoor temperature and combustion status, and accordingly turns on and off the drive relay 2 with an output signal B. The contact 2b is opened and closed to control the operation of the heating means 4. In addition, when operating the air purifying means 6 at the same time as heating, the microcomputer 1 uses the output signal C to operate the driving relay 3.
Turn on and off to open and close contact 3b, and the electricity s! The I-type air purifying means 6 is energized.

On the other hand, when operating the switch means 12 to stop the operation of the heating means 4 and only operate the air purifying means 6, the output signal B of the microcomputer 1 turns off the drive relay 2 and opens the contact 2b. At the same time, by setting the output signal D to rLJ, the transistor 9 is turned off, the self-holding circuit relay 10 is turned off, and the contact 10b is turned off.
Open. The manual switch 7 is configured as a switch that is turned on only when operated and kept off when not operated, and the self-holding circuit relay 10 is kept turned off.

In the unlikely event that the microcomputer 1 malfunctions, the heating means 4
Even if the output signal B is output to turn on the relay 2 for the m operation, since the coil power supply of the relay 2 is further cut off by the contact 10b of the relay 10 for the self-holding circuit, the WjA
The active relay 2 remains in the off state, and the heating means 4 is not energized.

On the other hand, the air purifying means S is configured with a parallel circuit so as not to be limited to the self-holding circuit relay 10 even when the self-holding circuit relay 10 is in the OFF state, and the coil power source of the driving relay 3 is Contact 10 of relay 10 for self-holding circuit
It is not retroactively determined by b.

Therefore, the drive relay 3 can be opened and closed by the output signal C of the microcomputer 1, and the air purifying means 6 can be energized.

In this way, when the air purifying means 6 is in the Mv4 state and the heating means 4 is in the non-operating state, the microcomputer 1 turns off the self-holding circuit relay 10.
Even if the microcomputer 1 malfunctions and the operation command signal for the heating hand 84 is not output, 'ts
The chamber means 4 is safe because it is never operated.

〔Effect of the invention〕

As described above, according to the present invention, the operation of the heating means is restricted by the self-holding means, and the operation of the air cleaning means is not restricted by the self-holding means. Since the microcomputer releases its self-holding means when the microcomputer is in a non-operating state, safety can be ensured even when the microcomputer malfunctions.

[Brief explanation of drawings]

FIG. 1 is a control circuit diagram showing one embodiment of the present invention, and FIG. 2 is a control circuit diagram of a conventional example. In the figure, 1 is a microcomputer, 2 is a heating means driving relay, and 3! ．． t Air cleaning means m Working relay, 7
is a manual switch, and 10 is a self-holding @road relay. Oh Iml

Claims (1)

[Claims] An electrostatic precipitator type air purifying means, a heating means for generating hot air, a self-holding means using an electromagnetic relay, and a microcomputer as a control means for controlling the air purifying means, the heating means, and the self-holding means. In the system, the operation of the heating means is restricted by the self-holding means, and the operation of the air purifying means is not restricted by the self-holding means, and when the air purifying means is in the operating state and the heating means is in the non-operating state, A control device for a hot air heater, characterized in that a microcomputer releases a self-holding means.