JP2022089030A - Gas distribution unit and water heater - Google Patents

Abstract

To stably and unevenly supply fuel gas to a space for distribution forming a branched channel.SOLUTION: A gas distribution unit 6 is assembled to a combustion device that houses a plurality of burners. The gas distribution unit has first and second branched channels 24, 25 that distribute and supply fuel gas to the burners. The first and second branched channels 24, 25 include first and second passage parts 24b, 25b1, 25b2, to which the fuel gas is introduced, and first and second spaces for distribution 24a, 25a, which are in communication with the downstream ends of the first and second passage parts 24b, 25b1, 25b2. The first and second spaces for distribution 24a, 25a have a plurality of nozzles 30, 30... disposed in parallel along a predetermined straight line direction, which inject fuel gas to the burners. In the second branched channel 25, the second passage part 25b1 communicates with the second space for distribution 25a in a direction orthogonal to the straight line direction in which the nozzles 30 are disposed in parallel with each other.SELECTED DRAWING: Figure 4

Description

The present invention relates to a gas distribution unit provided for distributing and supplying fuel gas to a plurality of burners in a water heater, and a water heater provided with the gas distribution unit.

The water heater is equipped with a combustion device equipped with a burner and a heat exchanger in the housing, and passes through the heat exchanger by the combustion exhaust of the burner that ignites and burns the mixture of the fuel gas and the combustion air. Heat the water to make it hot.
A plurality of flat burners are arranged in the thickness direction, and a gas distribution unit is provided on the upstream side. As disclosed in Patent Document 1, this gas distribution unit has a plurality of branch flow paths for branching fuel gas supplied from the upstream side, and the fuel gas is introduced on the upstream side of each branch flow path. On the downstream side of the passage portion, a distribution space is provided in which a plurality of nozzles corresponding to each burner are partitioned. Each passage portion can be opened and closed by a solenoid valve, and the number of burners to be burned can be adjusted by selecting a branch passage to which fuel gas is supplied by controlling the solenoid valve. The gas distribution unit is formed in a plate shape extending in the left-right direction, and is attached to the front surface of the casing forming the combustion chamber.

JP-A-2015-197273

In recent years, as the weight and size of appliances have been reduced, the size of gas distribution units has tended to be limited. In order to supply the necessary fuel gas to each nozzle, it is desirable to make the passage portion larger (wider passage area), but there are cases where the passage portion cannot be made larger due to layout reasons. For this reason, the fuel gas supplied from the passage portion to the distribution space tends to flow unevenly toward the nozzle near the passage portion, which may lead to deterioration of combustion performance.

Therefore, an object of the present invention is to provide a gas distribution unit and a water heater that can stably and evenly supply fuel gas to a distribution space forming a branch flow path.

In order to achieve the above object, the first invention of the present invention is assembled in a combustion device accommodating a plurality of burners, and includes a plurality of branch flow paths for distributing and supplying fuel gas to the burners. Each of the branch flow paths includes a passage portion into which the fuel gas is introduced and a distribution space communicating with the downstream end of the passage portion. Is a gas distribution unit in which the nozzles of the above are arranged side by side in a predetermined linear direction.
In at least one of the branch flow paths, the passage portion is connected to the distribution space in a direction orthogonal to the linear direction in which the nozzles are juxtaposed.
It should be noted that the "orthogonal direction" includes not only strict orthogonality but also some errors.
Another aspect of the first invention is that, in the above configuration, the extension line of the center of the passage portion in the branch flow path of 1 is connected to the distribution space at a position deviating from the center of the nozzle. It is a feature.
In another aspect of the first invention, in the above configuration, the nozzles are arranged in parallel in two rows.
The passage portion in the first branch flow path is branched into two and connected to the distribution space, respectively, and one of the branched branch passage portions is for the distribution in a direction orthogonal to the linear direction. The other branch passage portion is connected to the space, and the other branch passage portion is connected to the distribution space in a direction parallel to the linear direction, and extension lines at the center of each branch passage portion are connected to each other in the linear direction and the orthogonal direction. It is characterized by intersecting within the area surrounded by the four adjacent nozzles.
The "parallel direction" includes not only strict parallelism but also some errors.
Another aspect of the first invention is characterized in that, in the above configuration, an attachment portion to the combustion device is provided between the two branch passage portions.
In order to achieve the above object, the second invention of the present invention is a water heater, in which the gas distribution unit according to any one of the first inventions is assembled to a combustion device accommodating a plurality of burners. It is characterized by being.

According to the present invention, since the passage portion in one branch flow path is connected to the distribution space in a direction orthogonal to the linear direction in which the nozzles are juxtaposed, the passage portion is supplied to the distribution space. Fuel gas is biased toward the nozzle near the passage and becomes difficult to flow. Therefore, the fuel gas can be stably and evenly supplied to the distribution space forming the branch flow path.
According to another aspect in which the extension line of the center of the passage portion in the branch flow path 1 is connected to the distribution space at a position off the center of the nozzle, the bias of the fuel gas to the nozzle near the passage portion is caused. It can be effectively prevented.
According to another aspect in which the passage has two branch passages and the extension lines of the centers of the two branch passages intersect in the area surrounded by the four nozzles, the required flow rate can be secured. At the same time, the fuel gas flowing from the two branch passages can be made to collide with each other to better distribute the fuel gas.
According to another aspect in which the attachment portion to the combustion device is provided between the two branch passage portions, even if the two branch passage portions are provided, they can be closely attached to and fixed to the combustion device, and the sealing property can be improved. can.

It is a front view of the water heater with the front cover removed. It is an exploded perspective view from the front of a gas distribution unit. It is a perspective view from the rear of a gas distribution unit. It is a front view of the main body. It is an enlarged view of the concave part for 2nd distribution.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory view showing an example of a water heater, and shows the front surface with the front cover removed.
The water heater 1 has a combustion device 3, a heat exchanger 4, and an exhaust unit 5 installed in a square box-shaped housing 2. On the front surface of the combustion device 3, a gas distribution unit 6 for distributing and supplying fuel gas to a burner unit (not shown) in the combustion device 3 is assembled. The burner unit is formed by arranging a plurality of light and shade burners that are flat in the left-right direction in the left-right direction.
An air supply fan 7 for supplying combustion air is assembled on the lower surface of the combustion device 3, and a controller 8 provided with a control circuit board is arranged in front of the air supply fan 7. Air intakes 9, 9, ... Are formed on the back plate of the housing 2. The exhaust section 5 is formed with an exhaust stack 10 that penetrates the top plate of the housing 2 and projects upward.

A water supply pipe 11 is connected to the inlet end of the heat transfer tube of the heat exchanger 4, and a hot water outlet tube 12 is connected to the outlet end of the heat transfer tube. On the lower surface of the housing 2, a water inlet 13 to which an external water pipe is connected and a hot water outlet 14 to which an external pipe to a hot water tap is connected are provided. The upstream end of the water supply pipe 11 is connected to the water inlet 13, and the downstream end of the hot water outlet pipe 12 is connected to the hot water outlet 14.
Further, a gas inlet 15 to which an external gas pipe is connected is provided on the lower surface of the housing 2. The gas inlet 15 is connected to the gas distribution unit 6 in the housing 2 via a gas proportional valve unit 16 provided with a proportional valve and a main solenoid valve on the upstream side thereof.
The gas distribution unit 6 is assembled to the front surface of the inner case 17 so as to close the opening at the lower front surface of the inner case 17 of the combustion device 3 accommodating the burner unit. The frame rod 18 and the discharge electrode 19 are plugged and connected to the front surface of the inner case 17 on the upper side of the gas distribution unit 6.

As shown in FIGS. 2 and 3, the gas distribution unit 6 has a horizontally long flat shape formed by a main body 20 on the rear side and a lid 21 on the front side screwed to the main body 20 from the front. A seal body 22 is interposed between the main body 20 and the lid body 21.
In the gas distribution unit 6, the main body 20 and the lid 21 form a gas introduction section 23, and a first branch flow path 24 and a second branch flow path 25 branching from the gas introduction section 23. The first branch flow path 24 has a first distribution space 24a extending in the left-right direction on the upper side of the gas distribution unit 6 and a first passage portion 24b communicating with the first distribution space 24a and extending downward. There is. The second branch flow path 25 also has a second distribution space 25a that extends in the left-right direction on the left side of the first distribution space 24a, and two second passage portions 25b1 that communicate with the second distribution space 25a and extend downward. It has 25b2.
A cylindrical gas inlet 26 is projected backward on the lower left side of the rear surface of the main body 20 made of aluminum die-cast. A gas outlet portion (not shown) provided at the upper end of the gas proportional valve unit 16 is connected to the gas introduction port 26 from the rear.

As shown in FIG. 4, an inlet recess 27 that communicates with the gas introduction port 26 and forms the gas introduction portion 23 is recessed in the lower part of the front surface of the main body 20. In the upper part of the front surface of the main body 20, there is a first distribution recess 28 extending in the left-right direction to form a first distribution space 24a, and a second distribution recess 28 extending in the left-right direction to form a second distribution space 25a. 29 is recessed. The first and second distribution recesses 28 and 29 have a horizontally long rectangular shape extending in the left-right direction, and the first distribution recess 28 is formed longer in the left-right direction than the second distribution recess 29. At the bottom of the first and second distribution recesses 28, 29, a plurality of nozzles 30, 30 ... There is. The rows of nozzles 30, 30 ... Are formed in parallel in two rows vertically. A pair of upper and lower nozzles 30, 30 correspond to a light gas supply hole and a concentrated gas supply hole of each of the light and light burners constituting the first and second burner groups. The pair of nozzles 30 has 8 sets of first distribution recesses 28 and 4 sets of second distribution recesses 29, and the number of sets of first distribution recesses 28 is larger.

On the other hand, a first inlet 31 and a second inlet 32 penetrating back and forth are formed on the upper left and right sides of the entry-side recess 27, and communicate with the entry-side recess 27, respectively. On the back surface of the main body 20, the first and second inlets 31 and 32 are provided with solenoid valves 33 and 33 (FIG. 3) that open and close the communication portion with the inlet recess 27.
At the first entrance 31, a bent first passage recess 34 is continuously formed, which extends upward and then bends to the right and communicates with the lower part of the first distribution recess 28 over the entire length. The first passage recess 34 forms the first passage portion 24b.
At the second entrance 32, second passage recesses 35 and 36 are continuously formed, which are branched into two and are connected to the second distribution recess 29, respectively. The second passage recess 35 is formed in a semicircular shape that branches to the right and curves upward, and is connected orthogonally to the lower left end of the second distribution recess 29. The second passage recess 36 is formed in an inverted L shape that extends upward and then bends to the right, and is connected orthogonally to the left end of the second distribution recess 29. The second passage recess 35 forms the second passage portion 25b1, and the second passage recess 36 forms the second passage portion 25b2.

Here, as shown in FIG. 5, in the second passage recess 35, the extension line L1 passing through the center of the second passage recess 35 (second passage portion 25b1) is located on the left side of the second distribution recess 29. It is connected to the lower end of the second distribution recess 29 so as to pass between the four nozzles 30, 30 ... (hereinafter, referred to as "30L, 30L" when distinguishing). That is, the extension line L1 is deviated from the center O of each nozzle 30L in the left-right direction in the front view.
Further, in the second passage recess 36, the extension line L2 passing through the center of the second passage recess 36 (second passage portion 25b2) passes between the upper and lower nozzles 30L and 30L in the second distribution recess 29. Is connected to the left end of the second distribution recess 29. That is, the extension line L2 is vertically deviated from the center O of each nozzle 30L in the front view.
Therefore, the extension line L1 of the second passage portion 25b1 and the extension line L2 of the second passage portion 25b2 intersect at the intersection P in the region surrounded by the four nozzles 30L in the second distribution recess 29.

Around the first and second distribution recesses 28 and 29, the first passage recess 34, the second passage recess 35 and 36, and the entry side recess 27, there are screw holes 37 for screwing the lid 21. 37 ... is formed. Further, on the outside of the area surrounded by the screw holes 37, the main body 20 is formed with mounting holes 38, 38, ... For screwing to the inner case 17. The mounting hole 38 is also formed between the second passage recesses 35 and 36 (denoted as "38A" for distinction).

The lid 21 is a metal plate that covers the area including the first and second distribution recesses 28 and 29, the first passage recess 34, the second passage recesses 35 and 36, and the entry side recess 27 from the front. The lid 21 is formed with a first bulging portion 40 straddling the first distribution recess 28 and the first passage recess 34. The first branch flow path 24 is formed by the first bulging portion 40, the first distribution recess 28, and the first passage recess 34.
Further, the lid 21 is formed with a second bulging portion 41 straddling the second distribution recess 29 and the second passage recesses 35 and 36. The second bulging portion 41 also branches in accordance with the recesses 35 and 36 for the second passage. The second branch flow path 25 is formed by the second bulging portion 41, the second distribution recess 29, and the second passage recesses 35 and 36.
Below both the bulging portions 40 and 41, a third bulging portion 42 located in front of the entry-side recess 27 is formed. The gas introduction portion 23 is formed by the third bulging portion 42 and the entry side recess 27.
Through holes 43, 43, ... For screwing the lid 21 to the screw holes 37 of the main body 20 are formed around the bulging portions 40 to 42 in the lid 21. Further, a through hole 44 corresponding to the mounting hole 38 of the main body 20 is formed between the branch portions corresponding to the second passage portions 25b1, 25b2 in the second bulging portion 41.

The seal body 22 includes the first and second distribution recesses 28 and 29 of the main body 20, the first passage recess 34, the second passage recesses 35 and 36, the periphery of the entry side recess 27, and the first distribution recess 28. The first passage recess 34 is connected in a mesh pattern between the second distribution recess 29 and the second passage recesses 35 and 36, and is interposed between the main body 20 and the lid 21. Small holes 45, 45 ... Are formed at positions corresponding to the screw holes 37 of the main body 20.
Therefore, the seal body 22 is positioned on the front surface of the main body 20 to which the electromagnetic valves 33, 33 are assembled, and the screws 46, 46 ... When 1) is screwed in, the lid body 21 is screwed to the main body 20 via the seal body 22. Then, the main body 20 is set on the front surface of the inner case 17, the gas proportional valve unit 16 is connected to the gas introduction port 26, and fixed with screws 47, 47 ... (FIG. 1) at the positions of the mounting holes 38, 38A. Then, the assembly of the gas distribution unit 6 is completed.

In the water heater 1 configured as described above, when the hot water tap connected to the pipe of the hot water outlet 14 is opened and water is passed through the appliance, the controller 8 that detects this is the source of the gas proportional valve unit 16. The solenoid valve is opened and the proportional valve is controlled to a predetermined opening at the time of ignition. Further, the controller 8 opens the solenoid valves 33 and 33 of the corresponding first and second branch flow paths 24 and 25, and operates the air supply fan 7 to supply combustion air. Therefore, the fuel gas is supplied to the gas distribution unit 6 via the gas proportional valve unit 16.
At this time, when the solenoid valve 33 opens in the first branch flow path 24, the fuel gas that has entered the gas introduction section 23 from the gas introduction port 26 rises along the first passage section 24b and has a first distribution. It enters the space 24a, diffuses, and is supplied from each nozzle 30 to each shade burner.

On the other hand, when the solenoid valve 33 opens in the second branch flow path 25, the fuel gas that has entered the gas introduction section 23 from the gas introduction port 26 branches into the second passage sections 25b1, 25b2, and then the second distribution. Enter the space 25a from the lower side and the left side. Then, as shown by the dotted line arrow in FIG. 5, the upward fuel gas that entered the second distribution space 25a from the second passage portion 25b1 and the lateral direction that entered the second distribution space 25a from the second passage portion 25b2. It collides with the fuel gas near the intersection P. Therefore, the fuel gas diffuses into the second distribution space 25a and flows evenly to each nozzle 30, and the bias toward the shading burner is suppressed.

Then, when the igniter is operated by the controller 8 and the discharge electrode 19 is continuously discharged, the air-fuel mixture ejected from the flame hole portion of each shade burner is burned. The combustion exhaust of the burner unit is heat-exchanged with the water passing through the heat transfer tube of the heat exchanger 4, becomes hot water of a set temperature, and is discharged from the hot water outlet pipe 12. The controller 8 adjusts the opening degree of the proportional valve according to the required combustion amount, adjusts the supply amount of fuel gas from the gas proportional valve unit 16, and continuously changes the rotation speed of the air supply fan 7. And maintain a predetermined air-fuel ratio. Further, the controller 8 selects the first and second burner groups and controls the number of combustions stepwise by controlling the opening and closing of the solenoid valves 33 and 33 of the gas distribution unit 6 according to the required combustion amount. In the second branch flow path 25 corresponding to the second burner group, the fuel gas flows evenly to each nozzle 30 as described above, so that the combustion performance of the second burner group can be maintained.

In the gas distribution unit 6 and the water heater 1 of the above-described embodiment, in the second branch flow path 25, the second passage portion 25b1 is a second distribution space 25a in a direction orthogonal to the linear direction in which the nozzles 30 are arranged side by side. Is connected with.
With this configuration, the fuel gas supplied from the second passage portion 25b1 to the second distribution space 25a is biased toward the nozzle 30 near the second passage portion 25b1 and is less likely to flow. Therefore, the fuel gas can be stably and evenly supplied to the second distribution space 25a forming the second branch flow path 25.
In particular, the extension line L1 at the center of the second passage portion 25b1 is connected to the second distribution space 25a at a position deviating from the center O of the nozzle 30L. Therefore, it is possible to effectively prevent the fuel gas from being biased toward the nozzle 30L near the second passage portion 25b1.

The nozzles 30 are arranged in parallel in two rows, and the second passage portions 25b1, 25b2 are branched into two and are connected to the second distribution space 25a, respectively. Further, one of the branched second passage portions 25b1 (branch passage portion) is connected to the second distribution space 25a in a direction orthogonal to the left-right direction in which the nozzles 30 are juxtaposed, and the other second passage portion 25b2. The (branch passage portion) is connected to the second distribution space 25a in parallel with the left-right direction in which the nozzles 30 are parallel, and the extension lines L1 and L2 at the center of the second passage portions 25b1, 25b2 are in the vertical and horizontal directions. It intersects at the intersection P in the area surrounded by the four nozzles 30L adjacent to each other.
Therefore, the required flow rate can be secured, and the fuel gas flowing from the two second passage portions 25b1, 25b2 can collide with each other to better distribute the fuel gas.
A mounting hole 38A (mounting portion) for the inner case 17 of the combustion device 3 is provided between the two second passage portions 25b1, 25b2. Therefore, even if the two second passage portions 25b1, 25b2 are provided, they can be brought into close contact with the inner case 17 and fixed, and the sealing property can be improved.

An example of the change will be described below.
In the gas distribution unit of the above embodiment, two passages are connected to the distribution space of the branch flow path on the left side, but depending on the structure of the gas distribution unit, the distribution space of the branch flow path on the right side is connected. You may connect the two passages. It is also possible to connect two passages to each of the left and right branch passages.
Further, the gas distribution unit may be provided with three or more branch flow paths. In this case as well, one or a plurality of branch passages connecting the two passages can be provided.
However, the number of passages is not limited to two, and only one passage may be provided which is connected in a direction orthogonal to the linear direction in which the nozzles are arranged side by side. A mode in which the extension line of the center of the passage portion is not offset from the center of the nozzle can also be adopted. The row of nozzles is not limited to two rows, and may be one row.
The configuration of the water heater itself is not limited to the above form. For example, the present invention can be applied to a type having a secondary heat exchanger to recover latent heat, or a type having a circuit on the bath side or a heating side.

1 ... water supply, 2 ... housing, 3 ... combustion device, 4 ... heat exchanger, 5 ... exhaust, 6 ... gas distribution unit, 8 ... controller, 11 ... water supply pipe, 12・ ・ Hot water pipe, 13 ・ ・ Water inlet, 14 ・ ・ Hot water outlet, 15 ・ ・ Gas inlet, 16 ・ ・ Gas supply unit, 17 ・ ・ Inner case, 20 ・ ・ Main body, 21 ・ ・ Lid, 23 ・ ・Gas introduction section, 24 ... 1st branch flow path, 24a ... 1st distribution space, 24b ... 1st passage section, 25 ... 2nd branch flow path, 25a ... 2nd distribution space, 25b1, 25b2 ... 2nd passage, 26 ... gas inlet, 27 ... entry side recess, 28 ... 1st distribution recess, 29 ... 2nd distribution recess, 30 ... nozzle, 34 ... 1st Passage recess, 35, 36 ... Second passage recess, 38, 38A ... Mounting hole, L1 ... Extension of the center of the second passage 25b1, L2 ... Extension of the center of the second passage 25b2 , P ... The intersection of extension lines L1 and L2.

Claims (5)

It is assembled in a combustion device that accommodates a plurality of burners, and includes a plurality of branch flow paths that distribute and supply fuel gas to the burners. Each of the branch flow paths has a passage portion into which the fuel gas is introduced and the passage. A gas distribution unit including a distribution space communicating with the downstream end of the portion, in which a plurality of nozzles for ejecting fuel gas to each burner are arranged side by side in a predetermined linear direction. ,
A gas distribution unit characterized in that, in at least one of the branch flow paths, the passage portion is connected to the distribution space in a direction orthogonal to the linear direction in which the nozzles are juxtaposed. The gas distribution unit according to claim 1, wherein the extension line of the center of the passage portion in the branch flow path of 1 is connected to the distribution space at a position deviating from the center of the nozzle. The nozzles are arranged side by side in two rows in parallel.
The passage portion in the branch flow path of 1 is branched into two and connected to the distribution space, and one of the branched branch passage portions is distributed in a direction orthogonal to the linear direction. The other branch passage portion is connected to the distribution space in a direction parallel to the linear direction, and the extension lines at the center of each branch passage portion are connected to each other in the linear direction and the orthogonal direction. The gas distribution unit according to claim 2, wherein the gas distribution unit intersects with each other in a region surrounded by the four nozzles adjacent to each other. The gas distribution unit according to claim 3, wherein an attachment portion to the combustion device is provided between the two branch passage portions. A water heater in which the gas distribution unit according to any one of claims 1 to 4 is assembled to a combustion device accommodating a plurality of burners.

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