JP6747929B2 - Exhaust adapter - Google Patents

Description

The present invention relates to an exhaust adapter for a combustion device in which an exhaust port is provided on the front surface of an outer case.

In this type of combustion device, if an obstacle exists in front of the installation location of the combustion device, the combustion exhaust gas discharged from the exhaust port hits the obstacle. Therefore, conventionally, an exhaust adapter may be attached to the front surface of the outer case in order to change the discharge direction of the combustion exhaust gas from the exhaust port according to the installation situation of the combustion device (see, for example, Patent Document 1). The exhaust adapter generally includes a base member facing the front surface of the outer case and having an inflow port facing the exhaust port, and a cover member that covers the base member and defines an exhaust passage between the base member. Equipped with.

By the way, in the combustion apparatus, Helmholtz type resonance is generated in the space from the combustion fan in the exterior casing that supplies air to the combustion section to the exhaust port. Then, when the exhaust adapter is attached, the exhaust passage length is extended, so that the Helmholtz type resonance frequency is lowered and approaches the frequency of combustion vibration, and a low frequency resonance sound of, for example, about 70 Hz is easily generated. ..

Here, as a countermeasure against the resonance sound, a method of vibrating the components of the housing with the vibration energy of the resonance sound to convert the vibration energy of the resonance sound into the kinetic energy of the housing to reduce the resonance sound is known. is there. By applying this method to the exhaust adapter, it is possible to vibrate the base member and the cover member, which are constituent members of the exhaust adapter, with a predetermined low frequency vibration energy contained in the combustion exhaust gas, that is, with low frequency resonance sound vibration energy. Therefore, it is conceivable that the plate is made of a considerably thin plate material having a plate thickness of about 0.4 mm.

However, in this case, the natural frequency of the exhaust adapter is lowered to approach the frequency of the low-frequency resonance sound, and the exhaust adapter resonates, so that the low-frequency resonance sound cannot be suppressed.

JP-A-9-145161

In view of the above points, the present invention has an object to provide an exhaust adapter capable of suppressing low-frequency resonance noise.

In order to solve the above problems, the present invention is mounted on the front surface of an exterior case of a combustion device in order to change the discharge direction of combustion exhaust gas from an exhaust port provided on the front surface according to the installation condition of the combustion device. An exhaust adapter, comprising: a base member having an inflow port facing the front surface of an outer case and facing an exhaust port; and a cover member covering the base member and defining an exhaust passage between the base member and the cover member. The one of the base member and the cover member is made of a thin plate material having a predetermined thickness so that it can vibrate with a predetermined low frequency vibration energy contained in the combustion exhaust gas. At least a part of the other member of the cover member has a rigidity holding portion having a plate thickness thicker than that of the one member, and the natural frequency of the exhaust adapter is the same as that of the other member. It is characterized in that it is made higher than in the case of being configured with.

According to the present invention, one member of the base member and the cover member is made of a thin plate material, so that one member is vibrated by the vibration energy of a predetermined low frequency contained in the combustion exhaust gas, that is, low frequency resonance sound. Can be made. Thereby, the vibration energy of the low frequency resonance sound can be converted into the kinetic energy of one member. Further, by providing the rigidity holding portion on the other member of the base member and the cover member, the natural frequency of the exhaust adapter is lowered as in the case where the other member is made of a thin plate material similar to the one member, so that the natural frequency is lowered. The low frequency resonance sound can be suppressed in combination with the fact that the vibration energy of the low frequency resonance sound can be converted into the kinetic energy of one member without approaching the frequency of the frequency resonance sound.

Further, in the present invention, it is preferable that the rigidity holding portion is configured by fixing another plate member to the plate member that is the main body of the other member. According to this, the plate thickness of the main body can be made relatively thin, and various processing such as drawing can be easily performed on this plate material, and the degree of freedom in design is increased.

Further, in this case, the other member is preferably a base member. According to this, since the base member is blindfolded in a state where the exhaust adapter is attached to the front surface of the outer case, even if another plate member is fixed to the plate member, which is the main body of the base member, by spot welding or the like, no welding mark is left It does not appear in the appearance and keeps good appearance.

The front view of the combustion device which attached the exhaust adapter of the embodiment of the present invention. The side view of the combustion apparatus of FIG. The expanded sectional view cut|disconnected by the III-III line of FIG. The perspective view which shows the attachment method of the exhaust adapter of embodiment. Sectional drawing in the state fixed to the exhaust port of the adapter attachment frame cut|disconnected by VV of FIG. The perspective view of the exhaust adapter of the embodiment in a disassembled state.

With reference to FIGS. 1 to 4, reference numeral 1 is an exterior case of a combustion device including a water heater. A front panel 11 which is a front surface of the outer case 1 is provided with a horizontally long cylindrical exhaust port 13 which projects forward through a horizontally long opening 12 formed in an upper portion thereof. The exterior case 1 contains a combustion section, a combustion fan that supplies combustion air to the combustion section, and a heat exchanger that heats water by heat exchange with combustion exhaust gas from the combustion section. The combustion exhaust gas that has passed through the heat exchanger is discharged from the exhaust port 13 to the outside.

Here, if there is an obstacle in front of the installation location of the combustion device, the combustion exhaust gas discharged from the exhaust port 13 will hit the obstacle. In this case, the exhaust adapter 2 that changes the discharge direction of the combustion exhaust gas from the exhaust port 13 to a direction other than the front, for example, the lateral direction is attached to the front panel 11.

With reference to FIGS. 3 and 6, the exhaust adapter 2 includes a base member 21 having a horizontally long inlet 211 facing the front panel 11 and facing the exhaust port 13, and a base member 21 covering the base member 21. A cover member 22 that defines the exhaust passage 2a therebetween, a lid member 23 that closes one lateral side end of the exhaust passage 2a, and an exhaust port member 24 that discharges combustion exhaust gas from the other lateral end of the exhaust passage 2a to the outside. It is composed of. The base member 21, the cover member 22, the lid member 23, and the exhaust port member 24 are all made of stainless steel.

The base member 21 has a horizontally long flat plate shape, and flange portions 212 bent forward are formed at both upper and lower edges thereof, and a seat 213 abutting against the front panel 11 is attached to a lower rear surface of the base member 21. Has been. The cover member 22 is composed of a horizontally long bent plate that is substantially U-shaped in a side view. Then, the upper and lower flange portions 212 of the base plate portion 21 are superposed on the outer surfaces of the rear edge portions of the upper and lower plate portions of the cover member 22 and spot welded to each other to form an internal space to be the exhaust passage 2a. Assemble the horizontally long cylinder.

The lid member 23 has a cylindrical bending flange portion 231 on the peripheral edge. Then, the lid member 23 is fixed to the tubular body by fixing the bending flange portion 231 to the tubular body with the screw 232 while being fitted to one end portion in the lateral direction of the tubular body. The exhaust port member 24 has a tubular portion 241 and a mesh-shaped exhaust guard 242 attached to the end surface of the tubular portion 241. Then, the exhaust port member 24 is fixed to the tubular body by fixing the tubular portion 241 to the tubular body by the screw 243 in a state where the tubular portion 241 is fitted in the other lateral end portion of the tubular body. The plate material of the lid member 23 and the exhaust port member 24 has a thickness of about 0.5 mm.

The exhaust adapter 2 assembled as described above is attached to the front panel 11 via the adapter attachment frame 3. As shown in FIG. 4, the adapter attachment frame 3 extends horizontally to the front of the exhaust port 13 and is fixed at two lateral positions of the annular frame 31 so as to straddle the upper and lower frame portions thereof. The mounting seat 32, which is U-shaped in side view, the fixing piece portion 33, which extends from both lateral ends of the annular frame 31, extends slightly forward, and bends inward in the lateral direction, and the annular frame 31 are separate bodies. The engaging piece 34 engages with the rear surface of the front end of the lateral end of the exhaust port 13. Then, as shown in FIG. 5, in a state where the annular frame 31 is superposed on the front end of the exhaust port 13 via the packing 311, the fixing piece portion 33 is fixed to the engaging piece 34 with the screw 331, and the adapter mounting frame 3 is exhausted. Secure to the front end of mouth 13. Then, with the mounting seat 32 inserted in the inlet 211 of the exhaust adapter 2, the peripheral portion of the inlet 211 on the rear surface of the base member 21 is superposed on the front surface of the annular frame 31 via the packing 312, and the front of the cover member 22 is covered. The plate portion is fixed to the front end of the mounting seat 32 with a screw 221 and the exhaust adapter 2 is attached.

By the way, when the exhaust adapter 2 is attached, the exhaust passage length is extended and the Helmholtz type resonance frequency generated in the combustion device is lowered to approach the frequency of combustion vibration, and a low frequency resonance sound of about 70 Hz is likely to be generated.

Therefore, in the present embodiment, the cover member 22 of the exhaust adapter 2 has a predetermined thin plate thickness so that the cover member 22 can be vibrated by vibration energy of a predetermined low frequency contained in the combustion exhaust gas, that is, a low frequency of about 70 Hz. For example, it is made of a thin plate material having a thickness of 0.4 mm. According to this, it is possible to vibrate the cover member 22 with the vibration energy of the low frequency resonance sound of about 70 Hz, and convert the vibration energy of the low frequency resonance sound into the kinetic energy of the cover member 22.

Here, not only the cover member 22 but also the base member 21 may be made of the same thin plate material as the cover member 22. However, in this case, the natural frequency of the exhaust adapter 2 decreases and approaches the frequency of the low-frequency resonance sound of about 70 Hz, the exhaust adapter 2 resonates, and the low-frequency resonance sound cannot be suppressed.

Therefore, in the present embodiment, the base member 21 is configured to have the rigid holding portion 25 having a plate thickness larger than that of the cover member 22 in at least a part thereof, and the natural frequency of the exhaust adapter 2 is set to the base member 21. The height is higher than that when the cover member 22 is made of the same thin plate material. More specifically, another plate member having a plate thickness of about 0.8 mm is located below the inflow port 211 on the inner surface of the plate member 21a having a plate thickness of about 0.5 mm, which is a main body of the base member 21. The rigid holding portion 25 is configured by fixing 25a by spot welding. According to this, the natural frequency of the exhaust adapter 2 does not approach the frequency of the low frequency resonance sound of about 70 Hz, and it is possible to convert the vibration energy of the low frequency resonance sound into the kinetic energy of the cover member 22. As a result, low frequency resonance can be suppressed.

The base member 21 may be made of a thick plate material having a thickness of about 0.8 mm so that the entire base member 21 serves as the rigidity holding portion 25. However, this makes it difficult to perform processing such as drawing on the base member 21. On the other hand, in the present embodiment, the plate material 21a, which is the main body of the base member 21, can be made relatively thin, and various processing such as drawing can be easily performed on the plate material 21a, which increases the degree of freedom in design. There are advantages.

It is also possible to form the base member 21 with a thin plate material and provide the cover member 22 with a rigidity holding portion. However, when another plate material is spot-welded to the plate material that is the main body of the cover member 22 to form the rigid holding portion, welding marks appear on the appearance and the appearance is damaged. On the other hand, in the present embodiment, even if welding marks are formed on the plate member 25a forming the rigidity holding portion 25 on the base member 21, the base member 21 is blindfolded with the exhaust adapter 2 attached to the front panel 11. Welding marks do not appear in the appearance, and the appearance is kept good, which is advantageous.

Although the embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited thereto. For example, the exhaust adapter 2 of the above-described embodiment changes the discharge direction of the combustion exhaust gas to the lateral direction, but the exhaust adapter 2 that changes the discharge direction to a direction other than the lateral direction such as diagonally forward and upward is also the same. The present invention can be applied. Further, the method of attaching the exhaust adapter 2 to the front panel 11 is not limited to that in the above embodiment.

DESCRIPTION OF SYMBOLS 1... Exterior case, 11... Front panel (front of exterior case), 13... Exhaust port, 2... Exhaust adapter, 2a... Exhaust passage, 21... Base member, 21a... Plate material which is the main body of the base member, 211... Inlet port , 22... cover member, 25... rigidity holding portion, 25a... another plate material.

Claims (3)

An exhaust adapter that is attached to the front of the outer case of the combustion device to change the discharge direction of the combustion exhaust gas from the exhaust port provided on the front according to the installation situation of the combustion device, and faces the front of the outer case. A base member having an inlet facing the exhaust port, and a cover member that covers the base member and defines an exhaust passage between the base member and
One of the base member and the cover member is made of a thin plate material having a predetermined thickness so that it can be vibrated by vibration energy of a predetermined low frequency contained in the combustion exhaust gas,
At least a part of the other member of the base member and the cover member has a rigid holding portion having a plate thickness thicker than that of the one member, and the natural frequency of the exhaust adapter is the same as that of the other member. The exhaust adapter is characterized in that it is made higher than when it is made of a thin plate material. The exhaust adapter according to claim 1, wherein the rigidity holding portion is configured by fixing another plate member to a plate member that is a main body of the other member. The exhaust adapter according to claim 2, wherein the other member is the base member.

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