JPS63254315A - Safety device for hot air space heater - Google Patents

Abstract

PURPOSE:To prevent the danger such as a damage to equipment, fire hazard, etc., by detecting the overheating due to the closing of a suction port by a temperature sensor and comparing the detected temperature with set temperatures in a plurality of stages by a temperature judging means to conduct suitable operation control. CONSTITUTION:Temperature T which is detected by a temperature sensor 8 is always compared by a temperature judgement device 12 with temperature TL which is set by a low level temperature setting device 9, temperature TM which is set by a medium temperature setting device 10, and temperature TH which is set by a high level temperature setting device 11 respectively. When T>=TH, the temperature judging device 12 sends a signal to an alarm device 13, and it operates and notifies the outside the clogging of the mesh of a filter 6 but the operation continues. Next, when T>=TM, the temperature judging device 12 sends a signal to an operation control device 14 to force its amount of combustion to be reduced. Further, when T>=TH, the temperature judging device 12 sends a signal to the operation control device 14 to stop the operation.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a safety device for preventing abnormal overheating of a hot air heater and a filter sign.

Conventional technology Conventional hot air heaters use bimetallic switches as overheating prevention devices to detect abnormal overheating and stop operation of the equipment to maintain safety.Furthermore, in the event that the bimetallic switch malfunctions, a double safety device is used to monitor the temperature. A fuse was installed to ensure safety in the event of abnormal overheating.

In addition to the above-mentioned overheating prevention device, a bimetal switch or thermistor has been used as a filter clogging sign detection device that alerts the user to abnormal conditions such as dust clogging in the intake port before abnormal overheating occurs.

Problems to be Solved by the Invention In general, the operating temperature of bimetal switches is set at a high temperature to prevent malfunction during normal speed rotation, so when the temperature rises moderately, the device is exposed to abnormally high temperatures for a long time until it operates. . Furthermore, since the bimetal switch itself has a large heat capacity, there is always a delay in operational response, and the device is exposed to high temperatures for a short period of time.

Furthermore, it is used as a sensor (hereinafter referred to as a filter sign device) to notify when the air intake port is clogged with dust, etc.
A device other than the above-mentioned overheating prevention device was installed. In this way, if the overheating prevention device and the filter signature device are installed separately, the overheating prevention device may be activated before the filter signature device is activated depending on various ways of blocking the intake port, reaction speed of the device, mounting position, etc. There was a risk of problems such as the equipment stopping due to activation. On the other hand, if the operating temperature of the overheating prevention device is lowered to make it more likely to discolor, even if the air intake port is momentarily blocked by a curtain, etc., the overheating prevention device will be activated and the appliance will stop operating. There was a problem that it was not easy to use, such as not getting warm.

The present invention solves the above-mentioned problems, and if the temperature reaches a point where even mild overheating of the appliance may cause damage to the appliance, the present invention quickly responds and stops the appliance, thereby preventing damage to the appliance or fire. It is an object of the present invention to provide a hot air heater that prevents the danger of overheating and prevents the inconsistency in which an overheating prevention device is activated before a conventional filter sign device is activated.

Means for Solving the Problems In order to achieve the above object, the hot air heater of the present invention has a temperature detecting means installed in the heat exchanger which is most quickly overheated due to blockage of the intake air, etc. Setting a temperature level that does not pose a problem even if the air inlet is clogged, or setting a temperature level that does not pose a problem in practical use by reducing the amount of combustion even if the intake port is blocked, or setting a temperature level that does not cause any problem in actual use even if the intake port is blocked, or it is necessary to stop the equipment due to overheating. A plurality of temperature setting means for setting temperature levels, etc.; a temperature determination means for determining whether the temperature detected by the temperature detection means has reached the set temperature of the plurality of stages; and an output signal from the temperature determination means. The structure is equipped with multiple safety measures.

Effect: With the above-described configuration, the present invention uses one temperature detection means to detect overheating caused by a blockage of the intake port, and compares the set temperature of multiple stages with the temperature detected by the temperature detection means using the temperature judgment means, and determines the temperature reached. By sending signals to multiple levels of safety measures in response to the temperature at which the appliance is heated, and controlling the operation appropriately to the status of the appliance, it is possible to improve the usability of the appliance, and to prevent damage to the appliance due to overheating and fires caused by it. Danger can be prevented.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

In Figure 1, 1 is an exterior case, 2 is a burner, 3 is a heat exchanger, 4 is a convection fan for hot air circulation, 5 is an intake port for hot air and combustion air, and 6 is installed at the intake port 5. filter, 7
8 is a hot air outlet, and 8 is a temperature detection means such as a thermocouple or thermistor, which is installed in the heat exchanger 3. 9 is a low level temperature setting means corresponding to the filter signature device, 1o is an intermediate temperature setting means corresponding to a state where the temporary combustion amount is reduced,
11 is a high-level temperature setting means to prevent overheating; 12
13 is a temperature determining means for comparing and determining the temperature detected by the temperature detecting means 8 and the temperature set by each of the low level, intermediate and high level temperature setting means 9.10.11; 13 is an output signal of the temperature determining means 12; 14 is a display or alarm means for notifying the outside of the clogging of the filter, and 14 is an operation control means for controlling operation stop, weak combustion, continuation, etc. based on the output signal of the temperature determination means 11. Here, the display or warning means 13 and the operation control means 14 correspond to multiple stages of safety means.

In the above configuration, the operation will be explained based on the flowchart showing the operating process in FIG.

When the burner 2 is combusted and the convection fan 4 is operated, warm air and combustion air are drawn from the intake port 5 through the filter 6. Then, the hot air exchanges heat with the heat exchanger 3, mixes with the combustion exhaust gas, rises in the hot air flow path, and is blown out from the blowing lower as hot air. Then, the temperature T detected by the temperature detection means 8 is converted into the temperature TL set by the low level temperature setting means 9.
The temperature determining means 12 constantly compares the temperature T1%ll set by 0 with the temperature TH set by the high level temperature setting means 11. When T≧TL, the temperature determining means 12 issues a signal to the alarm means 13, which activates to notify the outside that the filter 6 is clogged, but operation continues. Next, when the temperature reaches 127M, the temperature determination means 12 sends a signal to the operation control means 14 to forcibly reduce the combustion amount.

Furthermore, when T≧TH, the temperature determination means 12 issues a signal to the operation control means 14 to stop the operation.

In this embodiment, there are three stages, but it is also possible to set more stages.

Effects of the Invention As is clear from the above-mentioned embodiments, the present invention can change the temperature detected by one temperature detection means to, for example, a low set temperature that indicates filter clogging, an intermediate set temperature that reduces the amount of combustion, and a temperature that is determined by overheating. Since the alarm or display of filter clogging is performed and the operation of the equipment is controlled by comparing it with the high-level set temperature at which equipment operation is stopped, it is possible to know in an orderly manner how to prevent filter clogging and equipment overheating. The present invention is extremely useful as a safety device, and since only one temperature detection means is required, its structure can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a flowchart showing the operating process of this embodiment. 8...Temperature detection means, 9...Low level temperature setting means, 10...Intermediate temperature setting means, 12
...High level temperature setting means, 11...Temperature determination means, 13...Alarm means, 14...
...Operation control means. Agent's name Patent attorney Toshi Nakao Male One idiot? −
Baa 3-11 magazine exchange kudzu 4--1τsugikatsu fan figure 2

Claims (3)

[Claims] (1) In a heater including a heat generator, a heat exchanger, and a convection fan, a temperature detection means installed in the heat exchanger, a temperature setting means for setting a plurality of arbitrary temperature stages,
temperature determining means for comparing a plurality of temperature stages set by the temperature setting means and the temperature detected by the temperature detecting means; and a temperature determining means for comparing each of the plurality of arbitrarily set temperature stages and the temperature detected by the temperature detecting means. The hot air is characterized by comprising a plurality of safety means that operate in response to respective output signals from the temperature determination means that have determined that the temperature detected by the temperature detection means is higher than the temperature detected by the temperature detection means. Heater safety device. (2) A safety device for a warm air heater according to claim 1, which uses a thermocouple that generates an electromotive force proportional to temperature as the temperature detection means. (3) A safety device for a hot air heater according to claim 1, wherein a thermistor whose electrical resistance monotonically changes depending on the temperature is used as the temperature detection means.