JPS59120510A - Control device of bath hot-water heater - Google Patents

Abstract

PURPOSE:To prevent insufficient heating by connecting a high temperature thermoswitch, which is placed in OFF state at the temperature higher than the set temperature of a thermoswitch and placed in ON state at the temperature lower than said set temperature, to a hot-water boiler heating control circuit in parallel to the thermoswitch with possibility of changeover. CONSTITUTION:A high temperature thermoswitch 8, connected in parallel to a thermoswitch 7, is formed so that it can be switched by means of a change-over switch S2. In this structure, normally, the change-over switch S2 operates to place the thermoswitch 7 in ON state and the high temperature thermoswitch 8 in OFF state respectively and controls a hot-water boiler 6 by means of a low temperature thermoswitch. However, in case of insufficient heating temperature during the severe cold, the device is switched to the high temperature thermoswitch 8 side to raise the temperature of the hot-water boiler 6. Insufficient heating can be prevented by this structure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a hot water heating system for a bus.

As a heating device for a bus, a so-called hot water heating system has been developed in which cooling water for a running engine is heated in a hot water boiler and then introduced into a radiator to heat the interior of the bus.

The above-mentioned hot water heating system generally includes a water pump 1', a thermostat 4, and a radiator 3, as shown in Figure 1.
In a driving engine having an engine cooling water circulation circuit consisting of a water valve 13, which is the cooling water after cooling the engine 1 from the upstream side of the thermostat 4. The water is guided to a hot water boiler 6 via a water pump 5, and from the hot water boiler 6, while passing through a radiator 9 and a defroster 11, a heating fan 10- warms the air inside the vehicle, and a defroster fan 12 draws warm air to the glass. It is designed to defrost by spraying it on the inner surface and return to engine 1 again.

In the above, the thermostat 4 generally opens at about 72°C and fully opens at about 78°C, and the cooling water of the engine 1 is circulated through the radiator 3 and cooled by the radiator fan 2 before returning to the engine 1. , this d
The water temperature near the cooling water outlet of Heri Engine 1 is always approximately 75°.
Normally, it is kept at about C.

Therefore, the temperature of the water supplied from the outlet of the engine 1 to the heating circuit by the pump 5 is approximately 70° C., taking into account losses such as natural heat radiation along the piping.

The hot water boiler 6 is provided with a thermoswitch 7 that detects the temperature of the hot water and operates, so that the hot water temperature in the hot water boiler 6 reaches 6.
When the temperature drops to 0°C, the thermo switch 1 is turned on and the hot water boiler 6 heats the hot water inside the boiler, and the hot water inside the boiler reaches 70°C.
When CK occurs, thermo switch T is turned off and heating is stopped. This can be done, for example, when the vehicle is stopped and engine 1 is idling, when the vehicle is stopped frequently, when the vehicle is stopped frequently, or when driving downhill. Alternatively, the heating temperature is not lowered even when the engine output is small during warm-up operation or when the outside temperature is abnormally low and the engine cooling water temperature does not rise.

However, in the conventional hot water heating system as described above, when the outlet water temperature of the engine 1 exceeds the set temperature of the thermostat 4, it is cooled by the radiator 3 and never exceeds the upper limit of the set value of the thermostat 4, for example, 78°C. In addition, the maximum setting temperature of the thermoswitch 7 installed in the hot water boiler 6 must naturally be set below the setting temperature of the thermostat 4 (if the setting temperature of the thermoswitch is (If it is made more cylindrical, the hot water boiler will always be in a state of combustion heating, increasing fuel consumption and cannot be put into practical use.)Therefore, the temperature of the hot water supplied to the radiator 9 should never exceed the maximum setting of the thermostat 4, which is 78°C. This can happen, and if the outside temperature is abnormally low, the heating temperature will be insufficient.

In addition, buses generally have a long total length of 11 to 1,277 mm, and the engine is mounted at the rear and the defroster 11 must be installed near the driver's seat. In addition, since the arrangement is bent while avoiding chairs, fenders, etc., the flow resistance of drought water reaches a water column of 25 to 60 m at a hot water flow rate of about 60 I/min.The water pump 1' of engine 1 is 25 to Although it is designed to be able to send water at a high pressure of 60 m water column, pump 5 is normally electric and has a pumping capacity of about 577 L water column, and when it is dead, the pressure of water pump 1' is applied to pump 5 and water is sent to the heating string. However, when the engine load is heavy, such as when driving at high speed in cold weather or climbing a long hill, the cooling water temperature rises and the thermostat 4 is fully opened, and the pumping force of the water pump 1' is distributed to the radiator 3 side. As a result, the amount of water sent to the heating system decreases, making it impossible to supply sufficient heat, causing a problem in which the engine cooling water temperature rises but the heating capacity decreases.At this time, the water temperature is high, so hot water boiler 6 The thermostat T was turned off, resulting in insufficient heating.

The present invention aims to solve the conventional problems as described above, and the present invention will be explained below with reference to a practical example 57 shown in Fig. 2.6.

In the present invention, the temperature of hot water from the hot water boiler 6 to the radiator 9 of the general hot water heating system shown in FIG. High temperature thermo switch 8
Add.

Then, as shown in FIG. 2, the high temperature thermoswitch 8 is connected in parallel with the thermoswitch 7 in the hot water boiler control circuit from the power source E through the heating main switch S1 + thermoswitch 7 and from the heating device RW of the hot water boiler 6 to the ground. A changeover switch S2 is provided to connect to the thermoswitch 70 circuit and the high temperature thermoswitch 80 circuit, and to control the switching between the thermoswitch 70 circuit and the high temperature thermoswitch 80 circuit.
The circuit is set so that the high temperature thermo switch 80 circuit is turned on and the high temperature thermo switch 80 circuit is turned off, and the hot water boiler 6 is controlled by the low humidity side thermo switch 7 as before. When the heating temperature is insufficient in the running state, the selector switch S2 is switched to the high temperature thermoswitch 8 side, and the hot water boiler heats the hot water to a high temperature to increase the temperature of the hot water flowing through the radiator 9, thereby creating a strong heating state. This is how it was done.

It is desirable that the high-temperature thermoswitch 8 is set to turn off when the water temperature is 98 to 10°C, and turn on when the water temperature is lower than that. This set temperature is equal to the boiling point of water; ql/-1 temperature, but the hot water in the heating system is always at a low level of 1077 L water column (I K
Since the boiling point is raised by the pressure, there is no problem in practical use.

In Fig. 2, T is a chamber 1 crystal setting thermoswitch, and the relay mountain is activated by turning on and off the thermoswitch T1, and when the sp-vortex exceeds the set value, R and S+ are turned off and the thermostat is turned off. The circuit of the switch γ is cut off, and R82 is activated to cut off the circuit of the high temperature thermoswitch 80 and switch to the low/high thermoswitch 70fli, thereby keeping the indoor temperature almost constant.

FIG. 6 shows a second embodiment of the present invention, in which an outside air temperature sensor T2 and a relay R2 actuated by the sensor are used in place of the manual changeover switch S2 of the embodiment of FIG.
During normal heating, relay switch R8 is thermo switch γ
circuit side is turned on, high temperature thermo switch 80 circuit side is turned off, and conventional heating control is performed. However, when the outside temperature falls below the set value, outside temperature fi sensor T2 is turned on, relay R2 is activated, and the relay switch ) (8 is switched to turn on the high temperature thermoswitch 80 circuit, resulting in strong heating; the other i'4 configurations are the same as in Figure 2, and the same symbols as in Figure 2 are the same. represents the part of

In this example, the heating effect is automatically switched between strong and weak.
It is possible to reduce the burden of driving noise.

As described above, according to the present invention, in a bus heating system using a hot water boiler, it is possible to accurately prevent the conventional problem of insufficient heating with an extremely simple configuration, and it can bring about great practical effects. It is.

[Brief explanation of drawings]

FIG. 1 is a system explanatory diagram of a wet pig stall system to which the present invention is applied, and FIGS. 2 and 6 are control circuit diagrams showing embodiments of the present invention, respectively. 1...Engine, 1'...Water pump, 2...Radiator fan, 3...Radiator, 4...Thermostat, 5...Pump, 6...Wet water boiler, γ...
・Thermo switch, 8... High temperature thermo switch, 9.
...Radiator, 10...Heating fan, 11...Defroster, 12...Defroster fan, ■)...%
i? , S... Main switch, S2... Changeover switch, w-hot water boiler heating device, r-t, , , i
t, □...Relay, T,...Room temperature setting thermoswitch, T2...Outside temperature sensor. ``Ni Homare Giant Uji 1

Claims (2)

[Claims] (1) In a hot water heating system, cooling water after cooling the running engine of a bus is sent to a hot water boiler by a water pump, heated, and then guided to a radiator to heat the room.
The hot water boiler heating control circuit that goes from the power supply to the hot water boiler's built-in thermo switch) used to detect the temperature of the hot water between the wet water boiler and the radiator, and detect a temperature higher than the set temperature of the thermo switch. A control for a hot water heating system for a bus, characterized in that a high temperature thermoswitch that is turned off at a temperature and turned on at a temperature lower than that is connected in parallel with the thermoswitch, and a changeover switch is provided for switching between the thermoswitch and the high temperature thermoswitch. Device. (2) The changeover switch is automatically switched so that when the outside temperature is above a set value, the thermoswitch side is turned on, and when the outside temperature is below a predetermined value, the high temperature thermoswitch side is turned on. A control device for a hot water heating device for a bus according to claim 1.