JPH0553660A - Heating device - Google Patents

Abstract

PURPOSE:To prevent the unsafe operation of a heating device by monitoring the voltage difference of the AD input terminals of plural temperature detecting means for a fixed time to judge a short circuit among these detecting means when the difference of detected voltage is set within a fixed range and stopping the electrification of a heating means. CONSTITUTION:An AD input terminal short circuit detecting means 11 monitors the voltage of the AD input terminals of the temperature detecting means 5a and 5b in terms of software. Then the means 11 decides a short circuit between both means 5a and 5b if these means detect the voltage of the same level and stops the electrification of the heating means 3a and 3b. The electrification of both means 3a and 3b are also stopped by a temperature control means 6 even in such a case where the voltage of the AD input terminal of the means 5a is kept at a fixed level and does not change since it may possibly be considered that the AD input terminal of the means 5a has a short circuit with another terminal. As a result, such an unsafe case where the temperature is excessively increased can be prevented and the safety of a heating device is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device for electric carpets.

[0002]

2. Description of the Related Art As a conventional heat collecting device, there is one as shown in FIGS. In the figure, reference numeral 1 is a main body of an electric carpet, to which a controller 2 for controlling the temperature of the electric carpet is connected. Heating means 3 is provided in the main body 1.
a, 3b, and temperature detection sensors 4a, 4b for detecting the temperatures of the heating means 3a, 3b are provided. Further, the controller 2 includes temperature detection means 5a, 5b for converting the temperature of the temperature detection sensors 4a, 4b into voltage, temperature control means 6 for controlling the heating means 3a, 3b, temperature setting means 7, heating means switching means 8, power supply. A voltage fluctuation detecting means 9 and the like are provided. Also in FIG.
As shown in FIG. 5, when the temperature control means 6 is composed of a microcomputer, the voltages detected by the temperature detection means 5a and 5b are input to the AD input terminals 10a and 10b of the microcomputer. Further, the AD input terminal 10 of the temperature detecting means 5a, 5b
An AD input terminal 11 of the power supply voltage fluctuation detecting means 9 is connected adjacent to a and 10b.

In the above structure, the operation when only one heating means 3a is energized will be described. That is, when power supply to the heating means 3a is started, the temperature of the main body 1 on the heating means 3a side rises, and the temperature of the temperature detection sensor 4a provided in the main body 1 rises. Then temperature detection sensor 4
The impedance of a becomes small and the voltage of the temperature detecting means 5a becomes low. When the voltage set in advance by the temperature setting means 7 is reached, the energization of the heating means 3a is stopped.

When the energization of the heating means 3a is stopped, the temperature of the heating means 3a becomes low and the temperature of the temperature detecting sensor 4a provided in the main body 1 becomes low. When the temperature of the temperature detecting sensor 4a becomes lower, the impedance becomes higher and the voltage of the temperature detecting means 5a becomes higher. When the voltage set in advance by the temperature setting means 7 is reached, energization of the heating means 3a is started. In this way, the temperature of the temperature detection sensor 4a is detected as a voltage by the temperature detection means 5a, and the temperature control means 6 starts and stops the energization of the heating means 3a to control the temperature to the set temperature. ..

[0005]

However, in the above-described conventional configuration, when one heating means 3a of the plurality of heating means 3a, 3b is energized, in the microcomputer constituting the temperature control means 6, the heating side A of the temperature detecting means 5a
When the D input terminal 10a is short-circuited with the AD input terminal 10b of the adjacent non-heating side temperature detecting means 5b due to solder scraps or the like, the non-heating temperature detecting means 5b has a higher voltage, and thus the heating temperature detecting means. An electric current flows into 5a. Therefore, even if the temperature of the heating side of the carpet rises and the impedance of the temperature sensor 4a on the heating side decreases, the voltage of the temperature detecting means 5a on the heating side does not become sufficiently low, and the temperature setting means 7 The heating means 3a cannot be stopped at the set temperature of the main body. As a result, the temperature cannot be controlled, and the temperature of the carpet becomes too high, leading to unsafe operation.

The present invention solves the above-mentioned conventional problems, in which the AD input terminal of the temperature detecting means is adjacent to another AD.
(EN) Provided is a safe warming device capable of preventing unsafe operation in which the temperature of a carpet cannot be controlled and the temperature becomes too high when the short-circuit with the input terminal is interrupted.

[0007]

In order to achieve the above object, the present invention provides a plurality of heating means, a temperature setting means for setting a control temperature of the plurality of heating means, and a temperature of the plurality of heating means. A plurality of temperature detecting means for detecting and a temperature control means for controlling the plurality of heating means are provided, and when at least one of the plurality of heating means is energized, it corresponds to the energizing side heating means. The detection voltage of the temperature detection means and the detection voltage of the temperature detection means corresponding to the heating means on the non-energized side are compared for a certain period of time, and when the difference between both detection voltages is within a certain range, the heating means AD input terminal short-circuit detecting means for stopping energization is provided.

[0008]

With the above construction, the AD input terminal short-circuit detecting means monitors the AD input terminal voltages of the plurality of temperature detecting means for a certain period of time, and if the difference between the detected voltages is within a certain range, the temperature detecting means are short-circuited. Judgment is made and the energization of the heating means is stopped.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In the present embodiment, the same components as those shown in the above-mentioned conventional example are designated by the same reference numerals, and the description thereof will be omitted. The characteristic configuration of this embodiment is that the control unit described in the conventional example is provided with AD input terminal short-circuit detecting means. That is, the controller 10 for controlling the electric carpet
AD input terminal short-circuit detecting means 11 is provided adjacent to the output sides of the temperature detecting means 5a and 5b.

The operation will be described with the above configuration. That is, when one heating means 3a of the plurality of heating means 3a and 3b is energized for heating, in the microcomputer constituting the temperature control means 6, the AD input terminal 10 of the temperature detection means 5a is used.
a is another temperature detecting means 5b adjacent to each other by a solder scrap or the like.
When short-circuited with the AD input terminal 10b of
Since the voltage is higher than that, current flows into the temperature detecting means 5a. Therefore, even if the temperature of the heating means 3a of the main body 1 of the carpet becomes the set temperature of the temperature setting means 7 and the impedance of the temperature detection sensor 4a becomes small, the voltage of the temperature detection means 5a does not become sufficiently low and The heating means 3a cannot be stopped at the original set temperature of the setting means 7. The output voltage of the temperature detecting means 5b decreases and becomes the same as the output voltage of the temperature detecting means 5a.

FIG. 2 shows its operating characteristics. The output voltage characteristics of the temperature detecting means 5a, 5b in the normal state are shown by a solid line, and the output voltage characteristics when the adjacent temperature detecting means 5a, 5b are short-circuited. It is indicated by a broken line.

On the other hand, the AD input terminal 1 of the temperature detecting means 5b
Since the 0b voltage is not heated, the voltage remains high and does not change. Therefore, if it is normal, it is always different from the voltage of the AD input terminal 10a of the temperature detecting means 5a except at a certain moment. The AD input terminal short-circuit detection means 11 is a software, and the AD input terminals 10 of the plurality of temperature detection means 5a and 5b
The a and 10b voltages are monitored for a fixed time, and if the detected voltages are the same, it is determined that the temperature detecting means 5a and 5b are short-circuited, and the energization of all the heating means 3a and 3b is stopped. The voltage of the AD input terminals 10a, 10b is monitored for a certain period of time when the heating means 3a, 3b are energized and the half-energization of the heating means 3a is switched on the way. Are heating means 3a and 3b, respectively
This is because it takes time for the temperature difference to occur due to the energization and stoppage of.

Further, even when the voltage of the AD input terminal 10a of the temperature detecting means 5a in the temperature control means 6 does not change at a constant value, the AD input terminal 1 of the temperature detecting means 5a.
Since 0a may be short-circuited with other terminals, the power supply to the heating means 3a, 3b is stopped.

[0015]

As is apparent from the above-described embodiments, the warming device of the present invention has a plurality of heating means, a temperature setting means for setting a control temperature of the plurality of heating means, and a temperature of the plurality of heating means. A plurality of temperature detecting means for detecting, and a temperature control means for controlling the plurality of heating means are provided, and when at least one of the plurality of heating means is energized, it corresponds to the energizing side heating means. The detection voltage of the temperature detection means and the detection voltage of the temperature detection means corresponding to the heating means on the non-energized side are compared for a certain period of time, and when the difference between both detection voltages is within a certain range, the heating means is energized. AD input terminal short-circuit detecting means for stopping the operation is provided. With this configuration, when the AD input terminals of the plurality of temperature detecting means are short-circuited, the coincidence of the voltages of the plurality of temperature detecting means is detected. hand, By stopping the energization of the thermal means, it becomes impossible to control the temperature with respect to the original temperature setting,
Safety can be improved by preventing unsafe operation that the temperature becomes too high.

[Brief description of drawings]

FIG. 1 is a block diagram of a heating device according to an embodiment of the present invention.

[Fig. 2] Operating characteristic diagram of the heating device

FIG. 3 is a block diagram of a conventional heat collecting device.

FIG. 4 is a block diagram of the heating device.

[Fig. 5] Terminal arrangement diagram of the heating device

[Explanation of symbols]

 3a, 3b Heating means 5a, 5b Temperature detection means 6 Temperature control means 7 Temperature setting means 10 Controller 11 AD input terminal short-circuit detection means

Front page continuation (72) Inventor Masafumi Hashimoto 1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] 1. A plurality of heating means, a temperature setting means for setting a control temperature of the plurality of heating means, a plurality of temperature detecting means for detecting a temperature of the plurality of heating means, and a plurality of the heating means. A temperature control means for controlling, and when at least one of the plurality of heating means is energized, the detection voltage of the temperature detecting means corresponding to the heating means on the energizing side, and the heating on the non-energizing side. The detection voltage of the temperature detection means corresponding to the means is compared for a certain period of time, and when the difference between the two detection voltages is within a certain range, the heating device provided with the AD input terminal short-circuit detection means for stopping the energization of the heating means. ..