JPS5997430A - Safety circuit for hot-water floor heating system - Google Patents

Abstract

PURPOSE:To prevent a temperature controlling circuit from failing to control temperature when a temprature detecting sensor fails, or an open/close device for a hot-water flow path, or the contact point or the circuit to control the open/close device fails, by connecting a plurality of comparators in parallel in the temperature controlling circuit in a hot-water circulating floor heating system. CONSTITUTION:A voltage VA represents the voltage at the contact point of a resistor RE and a floor temperature sensor 6. A voltage VB represents the voltage at the contact point of resistors RA and RB, which is equivalent to the resistance value of a floor temprature sensor at the time in low temperature. A voltage VC represents the voltage at the contact point of resistors RC and RP, which is equivalent to the resistance value of a floor temperature sensor at the time in high temperature. The device is designed so that the voltages VB and VC are respectively given to the secondary and the tertiary comparators, by the outputs from which the control circuit for a thermal power supplier is driven. Accordingly, when the temperature is unable to be controlled and the floor temperature exceeds 75 deg.C by the causes of such as failure of a room temperature sensor, melting of the contact point of a relay to control a thermal valve, and conduction failure in a transistor or a comparator OPI to drive a relay, the voltages VA, VB, and VC make up such a relation as VB>VC>VA, and an output voltage from the comparator OP2 rises high. Then a thyrister SCR is driven and the contact point of a relay Ry2 is turned OFF, so that the power supply to the thermal power supplier 1 and supply of hot-water are stopped.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a safety circuit for a hot water floor heating system.

(Conventional technology) Figure 1 shows a typical hot water floor heating system.

A constant temperature (e.g. 80'C) from a heat source such as a gas water heater
) is circulated through the entire piping 2, inside the floor heating hot water panel 3, and gradually returned to the piping 2' to the υ heat gap. The switch is designed to control the temperature of the floor heating hot water panel 3.

The thermal valve 4 is heated by energizing the adjacent heater (for example, POSISTOR) 5, and the IL valve 4 opens to flow hot water to the entire floor heating panel 3, and by stopping the energization to the heater 5.
Valve 4 is closed to stop the supply of hot water.

The temperature control circuit 8 energizes the heater 5 based on the output signals of the bed temperature sensor 6 and the room temperature sensor 7, and the bed temperature and the room temperature are completely controlled by a circuit 39.

Figure 2 is an example of the temperature control circuit that is used in this glaze device. show. In the diagram, 14 is the power supply circuit, and 9
is a resistance thermistor path that connects the floor temperature sensor 6 and the room temperature sensor 7.
The room temperature detection voltage is determined by the floor temperature detection circuit, and the difference voltage between the floor temperature detection voltage and the room temperature detection voltage is amplified by a voltage amplification circuit, and variable oscillation is performed depending on the output voltage of this voltage amplification circuit. The duty of the oscillation output of the circuit 13 is varied in size, and the oscillation output of the variable duty oscillation circuit is used to connect the heater 5 of the thermal valve 4 to the heater 5 of the thermal valve 4 through the relay circuit 11.
′? ! : It has a one-way configuration that controls it. In other words, in response to the rise or fall of the bed temperature detected by the bed temperature detection circuit that detects the bed temperature, the period of one level of the oscillation output is shortened or
When the floor temperature becomes higher than a predetermined temperature, the relay Ry circuit is cut off), and this 7L turns off the heater 5.
When heating is completely stopped and the valve 4 is closed, and when the bed temperature falls below a predetermined temperature, the valve 4 is opened. □ to control the opening and closing of 4.

However, the floor temperature sensor 6 is generally installed at the inlet of the hot water floor panel, and is connected to the IL lead wire to the sensor section of the temperature control circuit. aflru. Therefore, if the floor temperature sensor +J6 is placed on the floor and wired, the structure is susceptible to mechanical stress, which increases the risk of wire breakage. A negative characteristic thermistor (NTC) is often used as a floor temperature sensor, and when the NTC is disconnected, the resistance value becomes infinite, which is a signal equivalent to a very low floor temperature. However, the temperature control circuit 41 was constantly energized, which caused the floor temperature to rise abnormally, causing danger.

In addition, hot water may be heated due to an uncontrolled state due to the @ wire of the room temperature sensor, failure due to melting layer of the contact of the relay that controls the heater 5 of the thermal valve 4, failure of the transistor for driving the relay or the comparator that controls all of the relays, etc. This may be caused by continuous hot water failure on the panel, or the thermal valve itself is stuck, causing the valve to open. It's dangerous. The present invention has been proposed to eliminate the above-mentioned drawbacks and risks.

(Object of the Invention) The present invention is provided in a temperature control circuit of a hot water circulation type floor heating system to control failure of a leakage detection sensor (rH), or a hot water flow path opening/closing device, and its switching device. The purpose of this is to provide a safe way to prevent loss of control due to failure of the two contact circuits, etc.

(Structure of the Invention) The third disadvantage is the temperature control circuit W of the present invention and, of course, it is not shown.
Switch SW? ]l-on, contact R of relay R)'2
``When It enters, heat m and machine control circuits are activated.

Ry+ is a relay, and the operation of this relay turns the heater 5 on and off, opening and closing four thermal valves. 14 indicates a power supply circuit. Reference numeral 7 designates a room temperature sensor, which is connected in series with the resistor R3. Both ends of this series circuit are connected to the power supply circuit 14. The six-layer sensor is connected in series with a resistor R1i, fL, and both ends of this series circuit are connected to the power supply circuit 14. Therefore, the connection point between the room temperature sensor 7 and the resistor R1 and the connection point between the floor temperature sensor 6 and the first resistor RE are tM, respectively.
This temperature processing circuit is provided with a signal voltage that is different from room temperature and bed temperature, and outputs a full signal corresponding to the difference between the two signal voltages. Moreover, the temperature adjustment circuit can be used to set a lower temperature level according to the user's preference (for example, if both ends are electrically connected).
This is done by making the voltage at the transformer contact connected to the 1st path the initial voltage. ), the outputs of both circuits are given to the first comparator oP, iL. Third
In this example, the resistor RB has a value equal to the resistance value of the section where the floor temperature sensor reaches 130°C, and is connected in series with the 1i142 resistor RA, rL, and both ends of this series circuit are [
Connected to both circuits 14. The fifth resistor RD is a clay resistor equal to the resistance value of the fc field when the floor temperature sensor reaches +75°C, and is connected in series with the fourth resistor Rc. Both ends of this series circuit are connected to the power supply N. On road 14! #: Knotted. I resisted again,
, = gA= go is selected n.

Therefore, the lth voltage at the connection point between the floor temperature sensor 6 and the resistor RE; the second voltage kVBs at the connection point between the resistors RA and RB; the third voltage t- at the connection point between the resistors Rc and RD; V
o, the non-inverting input terminal of the second comparator OP2 is c1; the inverting input terminal is VA s; the third comparator OP;

MA to the non-inverting input terminal and VB to the inverting input terminal of
are given respectively. Furthermore, the comparator opt, O
The outputs of P, are applied to the gates of thyristors SCR, via resistors H, ,R,', respectively. The relay Rh and the thyristor SCR are connected in series, and both ends of this series circuit are connected to the power supply circuit 14.

Further, the output of the comparator OP1 is applied to the base of the transistor Tr via the resistor Rak.
rI is connected in series with relay RyI, and both ends of this series circuit are connected to power supply path 14.

Next, 1121fl= will be explained.

Resistors RA and R (the value of 3 is selected to be equal to 1 circle of glaze. Also, RB is selected to have a resistance value equivalent to 30 U of the floor temperature sensor. In addition, RD is selected to have a resistance value corresponding to 75°C of the floor temperature sensor.When the single circuit is normal (when the floor is normally at a value of lθ°C to ω°C), the respective voltages vA, VB, ■The value of c is vB > VA > VC to ZC
, the output voltage of the comparator OP*#0P is a lower level voltage, and the gate of the thyristor SCR is not driven.

Next, consider the case when the floor temperature sensor 6 is disconnected. At this time, v,
= vcc and nasi, vA, trench B, v. 9, the output voltage of the comparator OP is high, and the current and star SCR are driven 2'L.
1 Relay contact R')'t turns off (NC contact 1
For convenience: When the relay coil is not traced, the contact is on and voltage is applied to the relay coil.When T'L'fc is applied, that is, when SCR is on, the contact becomes 1 release), the heat source machine stops, and hot water is supplied. will stop.

Next, the temperature sensor #, the thermal valve control relay, the contact melt layer, the relay drive tonister, and the comparator OP1.
Due to the continuity failure r#, the degree control became impossible, and as a result, the floor temperature exceeded 75℃, VA, V
B, VC(1) voltage increase, VB>v.

〉When there are 7 people, the output voltage of the comparator OR becomes high, and the Cyrisk SCR is activated.V-contact R')'
When t is turned off, the heat source device 1 is stopped and the supply of hot water is stopped, ensuring full operation.

Furthermore, from the cathode of the thyristor SCR to the light emitting diode L
By connecting the ED't and grounding it, it is also possible to make an audible display when a circuit trouble occurs.

(Effects of the Invention) As described in the paper, the present invention provides the connection between the resistance ktF, the voltage at the connection point of the floor temperature sensor 6, VA, the resistance RA, and the resistance RB corresponding to the resistance value of the floor temperature sensor at low temperature. Voltage at point VB %
Voltage (■) at the connection point between resistor R6 and resistor RD, which corresponds to the high temperature resistance value of the bed temperature sensor. , when the voltage vB,
vc 'ir respectively to the second g third comparator,
Since the outputs of these comparators drive the control paths of the heat source equipment, the safety of the equipment is maintained even in the event of a failure of the temperature control circuit or failure of the heat valve. - Can be secured. If it is necessary, a light-emitting diode or the like may be used to indicate that a malfunction has occurred, thereby informing the user of the occurrence of a malfunction.

[Brief explanation of drawings]

1- shows a hot water floor heating system, FIG. 2 shows a conventional temperature control circuit, and FIG. 3 shows a safety circuit of the hot water floor heating system of the present invention. l... Heat polishing machine, 2... Piping, 3...
... Floor heating hot water panel, 4... Thermal valve, 5.
...Heater, 6...Bed temperature sensor, 7...
...Room temperature sensor, 8...Temperature side 1 circuit,
14...Electronic circuit, OP+, OPz,
ops... 1st. Second. a third comparator,
R.E. ftA, RB, klo, R1)--=1tj, 1.
m2, 3rd. 4th and 5th resistance %, W+ Applicant Matsushita Electric Works Co., Ltd.

Claims (1)

[Claims] In the floor temperature control circuit, which controls the supply of hot water at room temperature to the floor hot water panel by opening and closing a thermal valve, the room temperature sensor and floor temperature sensor control the floor temperature within a certain temperature range. sarL; The output 'fl- of the temperature processing circuit which is given the b signal and generates a signal corresponding to the difference voltage between the two signal voltages;
The output of the temperature pHi1 path that sets the desired temperature level is applied to the non-inverting input terminal of a comparator with a ratio of 1, and the output of the temperature pHi1 path that sets the desired temperature level is applied to the inverting input terminal of the comparator. In the series path Llc between the first resistor and the floor temperature sensor, which is applied to the base of the transistor directly connected to the relay, and to which the power supply voltage is roughly applied to both ends, the first Let the voltage at the connection point between the resistor and the floor temperature sensor be the voltage ml, and when the power supply voltage is applied to both ends, the direct voltage between the resistor m2 and the third resistor Wr VC>
and the voltage at the connection point of the second and third resistors is the voltage of the entire set 2, and the fourth and -5th resistors with the power supply voltage applied to both ends
2 in a series circuit of resistors, and the voltage at the connection point between the fourth and fifth resistors is t - the third voltage, the inverting input terminal of the second comparator has the first voltage and the non-inverting input. A third voltage is applied to the terminal, and the second voltage is applied to the non-inverting input terminal of the third comparator. A safety route for a hot water floor heating system, characterized in that the output sound of each of the third comparators is given to the gate of a thyristor connected in series with a relay that controls a heat generator.