JPS6039620Y2 - Proportional control combustion device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a proportional control type combustion device, and is particularly designed to improve the temperature rise characteristics.

Conventional proportional control type combustion devices do not have a bypass circuit in the temperature control valve, and the fuel flow rate changes in proportion to the temperature difference between the constant set temperature and the temperature sensing part, and as the temperature of the controlled part rises. Input is reduced.

For this reason, compared to the case of 0NN-OFF control (■) in Figure 1, it takes a long time to reach the set temperature TC of the temperature control valve, as shown in Figure I, resulting in poor usability and sensitivity. If the engine is started at a temperature close to the set temperature, the ignition performance may deteriorate due to the low fuel flow rate.

This idea solves the conventional problems mentioned above.
Proportional control uses a bypass valve in parallel with the temperature control valve to speed up temperature rise without sacrificing the smooth control characteristics of ratio series control, and to ensure ignition performance over a wide temperature range. The aim is to provide a type combustion device.

This invention is distantly related to the above purpose, so the temperature of the controlled object of the combustion device is detected by a temperature sensing part, and fuel is supplied in contrast to the temperature difference between the temperature detected by the temperature sensing part and the set temperature. In a device that has a temperature control valve that maintains a set temperature by controlling the temperature, a bypass valve is provided in parallel with the temperature control valve, and the power supply corridor of the electromagnetic coil that closes and operates the bypass valve is provided with a combustion device. A switch is connected to the temperature sensing part of the temperature control valve and the temperature detected by the temperature sensing part is connected to a switch that is temporarily closed when the knob is opened for the start operation in conjunction with the opening operation of the knob. A series circuit is provided with the contact point of the thermostat for closing the bypass valve, which opens when the temperature exceeds a predetermined temperature, and a relay coil for self-holding is connected in parallel to the electromagnetic coil, and the relay coil is closed by energizing the relay coil. After the switch is closed by a holding circuit including this contact and the relay coil, the bypass valve is opened when the bypass valve closing thermostat detects a predetermined temperature and the bypass valve is opened. It is designed to hold up to.

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

FIG. 2 shows the basic configuration of this devised device.A main nozzle 2 is provided at the tip of a main pipe 1 connected to a fuel supply source, and this main nozzle 2 is connected to a mixing chamber of a main burner 3. It's a dream.

In addition, the main conduit 1 has a main opening/closing cock 4 having a knob 4a, a pressure regulator 5, and a temperature regulating valve having a temperature sensing part 7 connected to a temperature regulating knob 6a via a thermostat connection part 7a. 6 are provided in series, and a bypass valve 9 is connected in parallel between the fuel inflow side and the discharge side of the temperature control valve 6 via a bypass conduit.

Therefore, the fuel from the supply source is supplied to the knob 4 of the main opening/closing cock 4.
By turning a, the pressure passes through the main opening/closing cock 4, and is adjusted to a constant secondary pressure by the pressure regulator 5 against changes in the primary pressure and flow rate.

The fuel that has exited the pressure regulator 5 is separated into a temperature control valve 6 passage and a bypass conduit 8 passage, and the separated fuel is reunited on the discharge side of the temperature control valve 6 and passes through the main pipe 1 to the main nozzle 2. It is blown out into the mixing chamber of the main burner 3.

In addition, when the bypass valve 9 is open, the outlet pressure of the pressure regulator 5 and the main nozzle 2 are set at 1 via the bypass valve 9 regardless of the opening degree of the temperature control valve 6.
00% flow rate of fuel will be ejected from the main nozzle 2.

On the other hand, when the bypass valve 9 is closed, the fuel passes only through the temperature control valve 6 and is regulated to a set flow rate based on the temperature difference between the set temperature of the temperature control valve 6 and the temperature of the temperature sensing section 7.

Therefore, by opening the bypass valve 9 as necessary, the flow rate can be adjusted to 100% regardless of the flow rate control of the temperature control valve 6.
This allows a large amount of fuel to flow into the main nozzle 2, making it possible to speed up the rise in temperature when starting up the combustion device.

Note that 10 is a DC power source, and 13 is a bypass valve closing thermostat connected to the temperature sensing portion 7 of the temperature control valve 6 via a connecting portion, and has a valve closing temperature setting knob 13a.

This bypass valve closing thermostat 13 has a built-in contact (not shown) that automatically opens when the temperature of the temperature sensing section 7 is detected to be higher than a predetermined temperature, and the DC power source 10 connects the electromagnetic coil of the bypass valve 9. The bypass valve 9 operates to close the bypass valve 9 by cutting off the current to the bypass valve 9a.

The temperature at which the built-in contacts open can be adjusted using the valve closing temperature setting knob 13a.

FIG. 3 shows a specific embodiment of this invention based on the above principle. In a control circuit having the same components as in FIG. It has a switch 12 that is temporarily closed in conjunction with the opening operation of the knob 4d of the cock 4, and a knob 13a for setting the valve closing temperature, and also connects the temperature sensing part 7 of the temperature control valve 6 and the thermostat connection part 7g. A bypass valve closing thermostat 13 whose contact point opens when the set temperature is reached is connected in series with the electromagnetic coil 9.
A self-holding relay coil 14 is connected in parallel to a, and a contact 15 that is turned on (closed) by this relay coil 14 is connected in series with the relay coil 14 and in parallel with the switch 12. be.

In the device having such a configuration, when the knob 4d of the main opening/closing cock 4 is opened for activation, the switch 12 that is linked thereto is temporarily closed.

Here, if the temperature of the temperature sensing part 7 with respect to the bypass valve closing thermostat 13 is lower than the closing temperature of the bypass valve 9, the bypass valve closing thermostat 1
Since the built-in contacts (not shown) in the electromagnetic coil 9a are closed, the power supply circuit of the electromagnetic coil 9a is closed, and at the same time, it is self-maintained by the relay coil 14.

As a result, bypass valve 9 is opened, and contact 1
5 and relay coil 14, this state is maintained and 100% flow rate of fuel is supplied to the main nozzle 2 side through the bypass valve 9 regardless of the opening degree of the temperature control valve 6.

Furthermore, when the temperature of the temperature sensing section 7 reaches the closing temperature of the bypass valve due to the combustion operation of the combustion device, the built-in contact (not shown) of the bypass valve closing thermostat 13 automatically opens and the electromagnetic coil The power supply circuit 9a is opened and the combustion device is shifted to proportional control using the temperature control valve 6.

Note that the switch 12 is the knob 4a of the main opening/closing cock 4.
When the knob 4a is opened from the closed state, it is temporarily closed in conjunction with the opening operation, but conversely, even when the knob 4a is closed from the open state, it is not opened accordingly.

In the embodiment shown in FIG. 3, the self-holding circuit of the bypass valve 9 is released when the bypass valve 9 reaches its closing temperature, so opening the bypass valve 9 forces the flow rate to 100%. While fuel is flowing, the temperature is always lower than the closing temperature of the bypass valve 9, and the temperature does not rise excessively.

Therefore, in the embodiment shown in FIG. 3, there is no fear that the temperature of the controlled object cannot be adjusted while the bypass valve 9 is open, or that the temperature of the controlled object exceeds the set temperature of the temperature control valve 6, which is better. control is possible.

In the configuration of the embodiment shown in FIG. 3, if the closing temperature of the bypass valve 9 is TBC, the opening temperature of the bypass valve 9 is TBO, and the temperature of the temperature control valve 6 is Tc, the main opening/closing cock 4 is operated. After starting the combustion device with
Until C, 100% fuel flows from the bypass valve 9 to the main nozzle 2 side.

Here, in order to speed up the temperature rise, it is desirable to bring 'rac closer to To.

Differential of bypass valve closing thermostat 13 (difference between valve opening temperature and valve closing temperature) ΔT=T, o-T
,.

When is O, TB is used to obtain proportional control characteristics near Tc.

<Tc must be set, but in this case, MoTa
Until c, 100% fuel is supplied from the bypass valve 9, so the temperature rise and ignition performance are improved.

When ΔT>O, if TBo=To is set, in the device with the configuration shown in FIG. 3, fuel is supplied from the bypass valve 9 at 100% flow rate until the temperature of the controlled object reaches Tc in FIG. can be made even faster.

The solid line in FIG. 4 is the temperature characteristic when ΔT>0.

In this way, if the bypass valve closing thermostat 13 is equipped with a differential, the temperature rise in the device configured as shown in FIG. 3 can be made more rapid at startup than in the case of a thermostat without such a differential. Better temperature control is possible.

Although each of the above-mentioned embodiments has been described with respect to combustion open to the atmosphere, this invention is not limited to this, and it goes without saying that it can also be applied to forced intake/exhaust type or forced exhaust type combustion.

Furthermore, as is clear from the above description of the embodiment, the flow rate of the fuel that ultimately flows to the main burner 3 side when the bypass valve 9 is open is not constant.

In other words, since the bypass valve 9 is a valve with a fixed flow rate, the flow rate is zero when closed and 100% when opened, but the degree of opening of the temperature control valve 6 changes depending on the temperature of the temperature sensing part 7. Because the flow rate does not change only between zero and 100%, but changes to an intermediate value between these two,
Even if the bypass valve 9 is open and the flow rate of the valve 9 is 100%, the flow rate of fuel to the main burner 3 is not constant because it is the sum of the flow rate from the temperature control valve 6.

Therefore, in the description of the above embodiment, when the bypass valve 9 is opened, 100% of the fuel is supplied to the main nozzle 2 side. This means that fuel is directly supplied from the temperature control valve 6 to the main nozzle 2 side. This is a flow rate that does not include the flow rate; in fact, in addition to the flow rate that passes through the bypass valve 9, there is also a flow rate from the temperature control valve 6, so the sum of these two flow rates is the flow rate of the fuel supplied to the main nozzle 2. It is what it is.

As described above, according to the devised device, a bypass valve is provided in parallel with the temperature control valve, and 100% of the fuel flows through the bypass valve to the combustion side, regardless of the flow rate of fuel flowing through the temperature control valve at the time of combustion startup. This makes it possible to improve the temperature rise characteristics and ignition performance at startup without losing the comfort of small temperature changes, which is a feature of proportional control, and has the advantage of simplifying the configuration. .

That is, by supplying a large amount of fuel at the time of startup of the combustion device, the ignition of the fuel becomes more reliable, the ignition performance improves, and the temperature rises better.

Furthermore, as a feature of this invention, the switch is temporarily closed in conjunction with the startup operation of the combustion device when the combustion device is started, and the contact point is maintained in the closed state even after the switch is closed. Since the bypass valve is automatically kept open from the time the combustion equipment starts operating until the predetermined set temperature is reached, the bypass valve can be opened even if the switch is not kept closed by a human. When the temperature is below a predetermined temperature, 100% of the fuel automatically flows through the bypass valve to the main nozzle side, regardless of the flow rate through the temperature control valve, to speed up the temperature rise and facilitate ignition. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the temperature rise characteristics of conventional proportional control and 0NN-OFF control, Fig. 2 is a basic configuration diagram of the proportional control type combustion device according to this invention, and Fig. 3 is a diagram showing a specific example of this device. The circuit configuration diagram shown in FIG. 4 is a temperature characteristic diagram of the embodiment shown in FIG. 3 of this invention. 1... Main pipe, 2... Main nozzle, 3... Main shut-
N, 4... Main opening/closing cock, 4a... Knob, 5...
・Pressure regulator, 6... Temperature control valve, 7... Temperature sensing part, 8... Bypass conduit, 9... Bypass valve,
10...Power supply, 11...Timer switch, 12.
...Switch, 13...Thermostat for closing the bypass valve, 14...Relay coil, 15...Contact.

Claims (1)

[Scope of utility model registration request] A temperature at which the temperature of the control target of the combustion device is detected by the temperature sensing section 7, and the amount of fuel supplied is controlled proportionally to the temperature difference between the temperature detected by the temperature sensing section and the set temperature to maintain the set temperature. In the device having the control valve 6, a bypass valve 9 is provided in parallel with the temperature control valve 6, and the power supply circuit of the electromagnetic coil 9a that opens the bypass valve 9 is provided with an open circuit for starting the combustion device. A switch 12 that is temporarily closed when the knob 4a is opened in conjunction with the opening operation of the knob 4a is connected to the temperature sensing section 7 of the temperature control valve 6, and the temperature detected by the temperature sensing section 7 is set to a predetermined value. A series circuit is provided with the contact point of the thermostat 13 for closing the bypass valve 9, which opens when the temperature exceeds the temperature, and a self-holding relay coil 14 is connected in parallel to the electromagnetic coil 9a, and further to this relay coil. After the switch 12 is closed, the bypass valve closing thermostat 13 detects the open state of the bypass valve 9 at a predetermined temperature after the switch 12 is closed by a holding circuit comprising a contact 15 that is closed when energized and the relay coil 14. A proportional control type combustion device configured to maintain the temperature until it is released.