JP5720874B2 - Combustion device - Google Patents

Description

The present invention relates to, for example, a combustion apparatus having a suitable fuel supply equipment for use in applications such supplying a fuel gas to the burner of a gas water heater.

  For example, in a gas hot water supply apparatus, there are cases where it is desired to change the drive combustion area of the burner or adjust the thermal power according to hot water supply conditions. As a fuel supply apparatus suitable for such a case, there is a conventional fuel supply apparatus as shown in FIG. The fuel supply device F shown in the figure has a nozzle head 8 having a plurality of nozzles 82 for ejecting fuel gas below a plurality of burners 9. A plurality of chambers 80 are defined in the nozzle head 8, and fuel gas can flow into each chamber 80 from the fuel gas supply path 81 through the opening 83. Each opening 83 can be opened and closed by an electromagnetic on-off valve Ve. The means using the electromagnetic on-off valve Ve is also described in Patent Document 1, for example.

  According to the configuration described above, the fuel supply to the plurality of chambers 80 can be individually turned on / off by individually controlling the opening / closing of the plurality of electromagnetic opening / closing valves Ve. Therefore, the fuel gas can be selectively supplied to only the desired burner 9 among the plurality of burners 9 to change the drive combustion area.

  However, the prior art has the following problems.

  That is, the electromagnetic on-off valve Ve is used as a means for switching on / off of the fuel supply to each chamber 80 of the nozzle head 8. This is a portion for allowing the entire amount of fuel gas burned in each burner 9 to pass. For this reason, the opening 83 has a relatively large diameter, and the flow rate of the fuel gas is large. Therefore, a large electromagnetic force is required to open and close the electromagnetic on-off valve Ve against the pressure of the fuel gas having such a large flow rate. As a result, it is necessary to use a large and expensive solenoid opening / closing valve Ve having a high output type solenoid. As a result, there is a problem that the manufacturing cost becomes expensive, and it is not so preferable for further energy saving.

  In a combustion apparatus that supplies combustion air to a burner using a fan, means for controlling a fuel supply pressure using a pressure regulating valve of a type called a pressure equalizing valve may be used (for example, , See Patent Document 2). However, the above-described pressure regulating valve is merely for controlling the fuel supply pressure to a pressure corresponding to the discharge pressure of the fan for the purpose of making the air-fuel ratio constant and improving the combustibility. Therefore, even if such a pressure regulating valve is incorporated in the fuel supply apparatus F shown in FIG. 5, it is necessary to provide the plurality of electromagnetic on-off valves Ve as they are, and the above-described problems cannot be solved.

JP-A-2005-351582 JP 2007-107865 A

The present invention has been conceived under the circumstances described above, and eliminates the need to use a large and expensive electromagnetic on-off valve or a similar valve, thereby reducing manufacturing costs and saving energy. that it can, moreover provides a plurality of combustion apparatus having a fuel supply equipment capable of adequately performing selective supply of fuel to such burner, and its challenge.

  In order to solve the above problems, the present invention takes the following technical means.

Combustion apparatus further provided to the onset Ming, a plurality of burners, a fuel supply device for supplying fuel to the plurality of burners, and a fan for supplying combustion air to the plurality of burners The fuel supply device has a plurality of chambers formed therein, and a nozzle head having a plurality of nozzles for ejecting fuel supplied to the plurality of chambers When the plurality of provided corresponding to each of the chambers, and includes a plurality of valves for switching individually on and off of the fuel supply to the plurality of chambers, as the plurality of valves, the signal A pressure input port, and a signal pressure is input to the input port, whereby the pressure of the fuel supplied to the plurality of chambers is a pressure corresponding to the signal pressure. A plurality of controllable pressure control valves are used. The signal pressure input mode for each of the plurality of pressure control valves is different from the first mode in which the control target pressure control valve is in the valve open state. A signal pressure switching means capable of switching to the second mode to be in a state, and in the first mode, the discharge pressure of the fan is used as the signal pressure, or for generating the signal pressure. In the second aspect, the secondary pressure of the pressure regulating valve to be controlled is used as the signal pressure, or used to generate the signal pressure, and the plurality of pressures By receiving the primary pressure, the secondary pressure of the regulating valve, and the discharge pressure of the fan, an auxiliary pressure capable of controlling each of the plurality of pressure regulating valves to a valve opening corresponding to the discharge pressure of the fan. The control valve is characterized in that it comprises further.

According to such a configuration, it is possible to individually turn on / off the fuel supply to the plurality of chambers of the nozzle head by individually switching the plurality of pressure regulating valves to the valve open or valve closed state. In addition, the following effects can also be obtained.
First, a plurality of pressure regulating valves are used as means for turning on / off the fuel supply. These pressure regulating valves are valves whose valve opening changes in accordance with the signal pressure. It is not necessary to drive using a solenoid or a motor. The signal pressure switching means only needs to have a function of switching the input mode of each signal pressure with respect to each pressure regulating valve. For example, even if configured using an electromagnetic valve, this electromagnetic valve is a high output type large-sized valve. There is no need to use anything. Therefore, according to the present invention, it is possible to eliminate or reduce the need for using a large solenoid valve or a similar valve, to reduce the manufacturing cost of the entire fuel supply device, and to save energy. it can.
Second, when each pressure regulating valve is opened, the pressure of the fuel flowing into the nozzle head chamber can be controlled to a predetermined pressure based on the inherent function of the pressure regulating valve. It is. Therefore, it is possible to eliminate the need to control the fuel supply pressure using a large-sized device separately from the plurality of pressure regulating valves.

Further, it is possible to selectively supply fuel to each of the plurality of burners from the fuel supply device, and appropriately change the drive combustion area of the plurality of burners.

Further, according to such a configuration, when the input mode of the signal pressure to each pressure regulating valve is the first mode, the fuel supply pressure to the burner becomes a pressure corresponding to the discharge pressure of the fan, and the air-fuel ratio is reduced. It can be kept constant. On the other hand, when the signal pressure input mode is the second mode, each pressure regulating valve can be appropriately maintained in the valve closed state.

Furthermore, according to such a configuration, although the total number of valves increases as much as the auxiliary pressure regulating valve is used, it is possible to suppress an increase in the overall size. That is, the auxiliary pressure regulating valve plays a role as a device for controlling the pressure regulating valve, but the auxiliary pressure regulating valve can be formed in a considerably small size. On the other hand, each pressure regulating valve is provided in the middle of the fuel supply path and controls the fuel supplied to the burner. Therefore, the pressure regulating valve needs to be formed in an appropriate size. As for, it is possible to suppress the enlargement as much as possible by reducing the stroke of the movable part, and this is an advantage in reducing the overall size.

  In the present invention, it is preferable that the signal pressure switching means is configured so that each of the plurality of fuel flow passages is provided at a location where the plurality of fuel flow passages connecting the plurality of pressure adjustment valves and the auxiliary pressure adjustment valve are aggregated. It has a two-way solenoid valve that can be opened and closed.

  According to such a configuration, the configuration of the signal pressure switching means can be simplified, and the manufacturing cost can be further reduced.

  Other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention with reference to the accompanying drawings.

It is sectional drawing which shows typically an example of the combustion apparatus to which this invention was applied. It is principal part sectional drawing which shows the fuel supply apparatus used for the combustion apparatus shown in FIG. It is principal part sectional drawing which shows the two-way solenoid valve for signal pressure switching used for the fuel supply apparatus shown in FIG. It is principal part sectional drawing which shows the operation state of the two-way solenoid valve shown in FIG. It is sectional drawing which shows an example of a prior art typically.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

  A combustion apparatus C shown in FIG. 1 is configured as a gas hot water supply apparatus provided with a heat exchanger 19 for heating hot water, and has a plurality of burners 2A to 2C, a fan 3, and a fuel supply apparatus arranged in the can 1. An FS and a control unit CN are provided. The fuel supply device FS includes a fuel supply path 4, an on-off valve Vc, a plurality of pressure regulating valves Va (Va1 to Va3), and auxiliary pressure regulating valves that are formed in series from the gas pipe 40 to the nozzle head 43 for gas ejection. Vb and a plurality of two-way solenoid valves Vd are provided. The two-way solenoid valve Vd corresponds to an example of the signal pressure switching means referred to in the present invention.

The nozzle head 43 has a plurality of nozzles 45 for ejecting fuel gas, and a plurality of chambers 44a to 44c corresponding to the burners 2A to 2C are defined in the nozzle head 43. In the drawing, the number of nozzles 45 is small, but actually, as described in Patent Document 1, for example, a large number of nozzles 45 are provided at a relatively small pitch. Further, the direction of the nozzle 45 does not have to be upward, and for example, a configuration in which the nozzle 45 faces in a substantially horizontal direction can be employed. The fuel gas ejected from the nozzle 45 is mixed with the combustion air sent from the fan 3 into the can 1 and supplied to the burners 2A to 2C for combustion. Heat is recovered from the combustion gas generated by this combustion by the heat exchanger 19, and hot water flowing through the heat exchanger 19 is heated. The combustion gas after heat recovery is discharged from the exhaust port 11 as exhaust gas.

  The on-off valve Vc is a valve that serves as a so-called main plug, and is used to turn on / off the fuel gas supply. Unlike the pressure regulating valve Va, the on-off valve Vc is an electromagnetic valve and includes a mechanism for reciprocating the valve main body 51 using a solenoid 50 (see FIG. 2).

  The plurality of pressure regulating valves Va perform the function of switching on / off the fuel supply to the plurality of chambers 44a to 44c and also controlling the fuel supply pressure during fuel supply. The plurality of pressure regulating valves Va are connected in parallel to the downstream side of the on-off valve Vc. Further, the downstream sides of the plurality of pressure regulating valves Va are individually connected to the fuel gas inlets 46 of the plurality of chambers 44a to 44c via the piping portions 47a to 47c.

  The basic configuration of each pressure regulating valve Va is the same as that of the conventional traditional pressure regulating valve, and as shown in FIG. 2, the boundary between the primary side flow path 4a and the secondary side flow path 4b of the fuel gas. A valve body 60 that opens and closes the pressure adjusting hole 42, a diaphragm D 1 that supports the valve body 60, a return spring 62, and a pressure receiving chamber 63. A signal pressure input port 64 communicates with the pressure receiving chamber 63, and the diaphragm D <b> 1 has a pressure (secondary pressure P <b> 2) in the secondary side flow path 4 b and a signal pressure (described later) input to the input port 64. Under pressure Pd or secondary pressure P2).

  The auxiliary pressure regulating valve Vb does not directly control the pressure in the fuel supply passage 4, but controls each pressure regulating valve Va. The auxiliary pressure regulating valve Vb includes a casing 70 whose interior is divided into a pressure receiving chamber 75a and a secondary pressure chamber 75b by a diaphragm D2, first and second springs S1, S2, a pressure regulating hole 72, and a valve main body 73. It has. The discharge pressure Ps of the fan 3 is supplied to the pressure receiving chamber 75a as a control signal pressure. More specifically, as shown in FIG. 1, a discharge pressure detection unit 32 for detecting the discharge pressure Ps of the fan 3 is provided in or near the discharge port of the fan 3. Ps is input to the pressure receiving chamber 75a through the piping section 76.

  The pressure adjusting hole 72 of the auxiliary pressure adjusting valve Vb is configured to be supplied with the primary pressure P1 of the fuel supply path 4 via the first flow path 74a having the orifice 49. The valve body 73 is a portion of the diaphragm D2 that faces the pressure adjusting hole 72. When the diaphragm D2 moves to the left in FIG. 2 and approaches the pressure adjusting hole 72, the amount of fuel gas that passes through the pressure adjusting hole 72 Has come to decrease.

The two-way solenoid valve Vd is for switching the input mode of the signal pressure to the input port 64 of the pressure regulating valve Va between a first mode and a second mode described later. The two-way electromagnetic valve Vd includes a second flow path 74b connected to the first flow path 74a, a third flow path 74c connected to the secondary pressure chamber 75b of the auxiliary pressure adjustment valve Vb, and the pressure adjustment valve Va. One end of each of the fourth flow path 74d connected to the secondary side flow path 4b and the fifth flow path 74e connected to the input port 64 is connected. As shown in FIG. 3, the two-way solenoid valve Vd uses a solenoid 55 to reciprocate the valve body 56, and is formed between the second and fifth flow paths 74b and 74e. 1
, The second opening 57b formed between the fourth and fifth flow paths 74d and 74e, and the third opening formed between the third and fourth flow paths 74c and 74d. Each of 57 c can be opened and closed by a valve body 56.

  FIGS. 4A and 4B show a case where the first mode and the second mode described above are set using the two-way solenoid valve Vd. Hereinafter, these first and second modes will be described.

First, in the first mode, as described below, the secondary pressure P2 on the downstream side of the pressure regulating valve Va is set to a pressure corresponding to the discharge pressure Ps of the fan 3 (for example, a pressure equivalent to the discharge pressure Ps). Can do.
That is, in the first mode shown in FIG. 4A, the first and third openings 57a and 57c are in the open state, and the second opening 57b is in the closed state. In this state, since the second and fifth flow paths 74b and 74e communicate with each other, the pressure Pd in the second flow path 74b is input to the input port 64 of the pressure regulating valve Va as a signal pressure. Here, the above-described pressure Pd corresponds to the valve opening degree of the auxiliary pressure regulating valve Vb. More specifically, if the distance between the valve main body 73 of the auxiliary pressure regulating valve Vb and the pressure adjusting hole 72 is large, the fuel gas in the first flow path 74a flows more into the second flow path 74b, so the pressure Pd Becomes lower. On the other hand, the pressure Pd increases as the distance decreases. In the first mode, since the third and fourth flow paths 74c and 74d communicate with each other, the secondary flow path 4b and the secondary pressure chamber 75b of the auxiliary pressure regulating valve Vb are connected. For this reason, the pressure of the secondary pressure chamber 75b becomes equal to the secondary pressure P2 of the secondary side flow path 4b.

  On the other hand, the discharge pressure Ps of the fan 3 is supplied to the pressure receiving chamber 75a of the auxiliary pressure regulating valve Vb, and the diaphragm D2 is pushed by the discharge pressure Ps and moves in a direction to close the pressure adjusting hole 72. In this case, the sum of the pressing force of the discharge pressure Ps on the diaphragm D2 and the pressing force of the first spring S1 is balanced with the sum of the pressing force of the secondary pressure P2 on the diaphragm D2 and the pressing force of the second spring S2. Diaphragm D2 moves to the position. As described above, the pressure Pd in the second flow path 74b depends on the position of the diaphragm D2. In the pressure regulating valve Va, the diaphragm P1 moves in the direction of increasing the valve opening degree by the pressure Pd. In this case, the secondary pressure P2 is balanced with the discharge pressure Ps supplied to the auxiliary pressure regulating valve Vb. Will be moved to. With such an operation principle, the secondary pressure P2 can be controlled to a pressure (for example, the same pressure) corresponding to the discharge pressure Ps.

Next, a 2nd aspect is demonstrated. In this second aspect, the pressure regulating valve Va can be closed.
That is, in the 2nd mode shown in Drawing 4 (b), the 2nd opening 57b is an open state, and the 1st and 3rd openings 57a and 57c are a closed state. In this state, since the fourth and fifth flow paths 74d and 74e are connected to each other, the secondary pressure P2 of the secondary side flow path 4b is input to the input port 64 as a signal pressure. The pressure regulating valve Va is not opened by such an input of the secondary pressure P2, but is kept closed. Since the third and fourth flow paths 74c and 74d are blocked from each other, the fuel gas does not pass through these flow paths and flow unfairly into the secondary flow path 4b.

  The control unit CN is configured using a microcomputer or the like. This control part CN performs operation control of each part of the combustion apparatus C, and various data processing. The switching operation of each two-way solenoid valve Vd is also controlled by this control unit CN.

  Next, the operation of the above-described combustion apparatus C will be described.

First, when all the burners 2A to 2C are driven and burned to obtain a strong thermal power, all of the plurality of two-way solenoid valves Vd are set to the state shown in FIG. 4A (first mode), Pressure Pd is input as a signal pressure to the input ports 64 of the pressure regulating valves Va1 to Va3. Accordingly, as described above, each of the pressure regulating valves Va1 to Va3 is opened, and the secondary pressure P2 is controlled to a pressure corresponding to the discharge pressure Ps of the fan 3. Accordingly, the fuel gas is appropriately supplied to each of the plurality of chambers 44a to 44c of the nozzle head 43, and drive combustion with a constant air-fuel ratio is performed in the burners 2A to 2C.

  Next, unlike the above, for example, when only the burner 2A is driven to burn and it is desired to stop the drive combustion of the burners 2B and 2C, two two-way solenoid valves Vd corresponding to the pressure regulating valves Va2 and Va3 are shown in FIG. The state shown in 4 (b) (second mode) is set. When such a setting is made, as described above, the secondary pressure P2 from the secondary flow path 4b is input to the input ports 64 of the pressure regulating valves Va2 and Va3, so that the pressure regulation is performed. The valves Va2 and Va3 are closed, and the fuel gas supply to the chambers 44b and 44c is stopped. Therefore, the drive combustion of the burners 2B and 2C can be stopped. Of course, in this case, the fuel gas can be supplied to the chamber 44a via the pressure regulating valve Va1, and the burner 2A can be driven and burned appropriately. Thus, in this combustion apparatus C, each of the burners 2A to 2C can be selectively driven and burned.

  In the combustion apparatus C of the present embodiment, a plurality of pressure regulating valves Va are used as means for individually turning on and off the supply of fuel gas to the plurality of chambers 44a to 44c. It is not necessary to use a solenoid or a motor as a drive source for Va. The same applies to the auxiliary pressure regulating valve Vb. The two-way solenoid valve Vd performs on / off of the fuel gas flow between the second to fifth flow paths 74b to 74e, and the second to fifth flow paths 74b to 74e have a small diameter. A large electromagnetic force is not required for the opening / closing operation of the two-way solenoid valve Vd. Therefore, the two-way solenoid valve Vd can be made small and inexpensive with a relatively low output. As described above, in the fuel supply device FS of the combustion device C, it is not necessary to incorporate a large solenoid valve in addition to the on-off valve Vc, and the manufacturing cost and energy saving of the entire device can be reduced.

  Further, according to this combustion apparatus C, a predetermined necessary pressure is transmitted from one auxiliary pressure regulating valve Vb to each of the plurality of pressure regulating valves Va, and the number of auxiliary pressure regulating valves Vb is minimized. It is a number. Therefore, for example, the configuration is rational as compared with the case where a plurality of auxiliary pressure regulating valves Vb are used. Further, as a means for switching the input mode of the signal pressure to the input port 64 of each pressure regulating valve Va, since the simple two-way electromagnetic valve Vd is used, the manufacturing cost of the entire apparatus is reduced. However, it becomes more preferable.

The present invention is not limited to the contents of the above-described embodiment. The specific configuration of each part of the combustion apparatus provided with the fuel supply apparatus according to the present invention can be varied in design in various ways.

In the above-described embodiment, the case where three chambers and burners in the nozzle head are provided is described as a specific example. However, the number is not limited as long as the number is plural .

As the signal pressure switching means in the present invention, an electromagnetic valve having a configuration different from the two-way electromagnetic valve as in the above embodiment or other valves can be used. The combustion apparatus according to the present invention is replaced with a hot water apparatus such as a hot water supply apparatus provided with a heat exchanger, for example, a fan heater, a stove,
It can also be configured as a combustion apparatus such as a combustion apparatus for incineration.

C Combustion device FS Fuel supply device Va Pressure regulating valve Vb Auxiliary pressure regulating valve Vd Two-way solenoid valve (signal pressure switching means)
2A to 2C Burner 3 Fan 43 Nozzle heads 44a to 44c Chamber (within the nozzle head)
45 Nozzle 64 Input port for signal pressure

Claims (2)

With multiple burners,
A fuel supply device for supplying fuel to the plurality of burners;
A fan for supplying combustion air to the plurality of burners;
A combustion device comprising:
The fuel supply device includes:
A plurality of chambers are formed therein, a nozzle head having a plurality of nozzles for ejecting fuel supplied to the plurality of chambers, and a plurality of chambers provided corresponding to each of the plurality of chambers. A plurality of valves for individually switching on and off of the fuel supply to the chambers ,
As the plurality of valves, there is an input port for signal pressure, and by inputting the signal pressure to the input port, the pressure of the fuel supplied to the plurality of chambers can be controlled to a pressure corresponding to the signal pressure. A plurality of pressure regulating valves are used, and a signal pressure input mode for each of the plurality of pressure regulating valves is set to a first mode in which the control target pressure regulating valve is in a valve open state and a valve closed state. A signal pressure switching means switchable to the second mode ,
In the first aspect, the discharge pressure of the fan is used as the signal pressure or used to generate the signal pressure. In the second aspect, the secondary pressure of the pressure regulating valve to be controlled is used. Is used as the signal pressure, or used to generate the signal pressure,
By receiving the primary pressure, the secondary pressure, and the discharge pressure of the fan, the plurality of pressure adjustment valves can each be controlled to a valve opening corresponding to the discharge pressure of the fan. A combustion apparatus further comprising an auxiliary pressure regulating valve . The signal pressure switching means is configured to be capable of opening and closing each of the plurality of fuel flow passages at a location where the plurality of fuel flow passages connecting the plurality of pressure adjustment valves and the auxiliary pressure adjustment valve are integrated. The combustion apparatus according to claim 1, comprising a two-way solenoid valve .

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