JPS5835527Y2 - Control circuit for hot water heating system with electric heating - Google Patents

Description

[Detailed description of the invention] The present invention relates to a heating device that uses both an electric heater and engine cooling water, and in particular prevents over-discharging of a battery due to the electric heater, and also prevents abnormal overheating of the electric heater and improves the safety of the device. It is something that enhances.

Vehicles such as buses use hot water heating systems that use engine cooling water to heat the interior of the vehicle during cold seasons. The desired heating effect cannot be obtained.

For this reason, in this type of heating system, a heating wire is installed in the hot air passage of the heat exchanger, and a temperature switch installed in the hot water passage of the heat exchanger controls the power supply to the heating wire. A method is being adopted in which the above defects are compensated for by using an electric heater while the cooling water temperature is low at the time of startup.

However, in order to obtain hot air that is warm enough to feel warm, the heater capacity must be increased to several thousand watts, and with a limited power supply capacity like a car, this kind of large power consumption is difficult. The reality is that various problems are being raised, such as the impact on other electrical equipment.

In addition, due to the large amount of heat generated, it has been pointed out that there are dangers associated with malfunctions of the heating equipment, such as blower failures.Therefore, with the spread of hot water heaters that combine electric heating, there is a strong desire to establish safe and energy-saving systems. The current situation is that

In line with the above-mentioned requirements for conventional products, the present invention has been developed by examining and improving the heater control system. It enables the heating wire to be energized only while the engine is running, and sets the energization time using a timer. Even within the set time of the timer, if the engine cooling water temperature rises and normal heating is performed, this is detected by the temperature switch placed at the hot air outlet and the heating wire is switched on. Detailed considerations have been made, such as turning off the electricity in the system, in an effort to achieve comprehensive energy savings and safety effects.

Embodiments of the present invention will be described with reference to the drawings.

Figure 1 shows the configuration of the heating device of the present invention, in which 1 is the housing of the device, 2 is a blower consisting of a motor 3 and a fan 4, and 5
is a heat exchanger.

Reference numeral 6 denotes a heating wire disposed in a hot air passage between the heat exchanger and the blower, and a temperature fuse 7 is provided adjacent to the heating wire.

8 is an air intake part, 9 is a hot air outlet, and a temperature switch 10 is disposed at this outlet.

FIG. 2 is an electrical circuit diagram, and the operation of the apparatus of the present invention will be specifically explained using FIG. 1 in conjunction with FIG.

When the engine start switch is operated, a voltage is applied to the terminal 11, and the semiconductor switching element 12, such as Cyrisk, is activated, and the heating device becomes ready for operation.

When the heating switch 14 is turned on to start the heating device, the motor 3 is energized, the blower is activated, and air is sucked through the input port 8.

Next, by operating the switch 13 for starting the electric heater, the timer 15 is activated, which energizes the relay 16 for controlling the electric heating circuit and closes its contact 161.
The heating wire is energized.

As the bus enters running mode and the temperature of the engine cooling water rises, the appropriate temperature can be achieved only by heating with hot water.

However, the time required for this varies depending on the driving style, outside temperature, etc., and uniform settings using a timer sometimes pose a risk of excessive heating or even burns caused by hot air.

Note that the timer is normally set to about 30 minutes, taking into consideration the heating effect under adverse conditions.

Therefore, in the present invention, when the engine coolant temperature rises quickly due to high traveling speed or high outside temperature, the temperature switch 10 detects the temperature of the hot air and opens the circuit of the relay 16. The contact point 161 is restored and the electric heating circuit is cut off.

Further, even if air cannot be blown due to an accident with the motor 3 while the heating wire is energized, the temperature fuse 7 detects the overheating state of the heating wire and shuts off the heating circuit.

FIG. 3 shows another embodiment in which the switches 13 and 14 are turned off for some reason while the heating wire 6 is energized.
Even in such a case, the timer 17 is activated and the blower is operated for several minutes after the heating wire stops heating, thereby cooling the heating wire.

As explained above, the heating device of the present invention allows electricity to be applied to the heating wire only while the engine is running, controls the timer for the company electric wire, and even within the set time of the timer, the heating wire is turned on by the engine cooling water. When proper heating is achieved, a temperature switch installed at the hot air outlet detects this and immediately stops powering the heating wire, reducing battery power consumption as much as possible. This aims to reduce the amount of heat generated, and also to ensure safety against harm to the human body due to overheating or fire.

[Brief explanation of drawings]

FIG. 1 shows the configuration of a heating device according to the present invention, FIG. 2 shows its electric circuit, and FIG. 3 shows another circuit diagram. 2...Blower, 5...Heat exchanger, 6.
... Heating wire, 7 ... Temperature fuse, 10
...Temperature switch, 12...Switch element, 15...Timer, 16...Relay.

Claims (1)

[Scope of utility model registration request] An electric heating wire for auxiliary heating is installed in the hot air passage of the hot water heating system that uses engine cooling water to warm the inside of the bus.
A control relay contact 161 and a temperature fuse 7 provided close to the heating wire are connected in series to the heating wire, and the heating current is controlled by a semiconductor switching element 12 that becomes conductive when the engine start switch is turned on. A control circuit for a hot water type heating device combined with a taillight, characterized in that the control circuit is operated by an electric circuit formed by connecting a timer 15, a control relay 16, and a temperature switch 10 provided at a hot air outlet in series.