JP5989564B2 - Liquid heating device - Google Patents

Description

  The present invention relates to a liquid heating apparatus such as a boiler or a fryer, and more particularly to a liquid heating apparatus that prevents partial deformation or the like that may occur at the bottom of a heating tank.

  Conventionally, as a liquid heating device such as a boiler or a fryer, a heat generating device such as a gas burner or an electric heater and a heating tank that opens on the upper surface of the housing and stores water and oil are stored in the housing, and combustion gas and A direct heating type liquid heating apparatus that directly heats the bottom of a heating tank with an electric heater is known (see Patent Document 1).

  In addition, as shown in FIGS. 8 and 9, such a liquid heating apparatus stands up from the outer surface of the bottom 101 of the heating tank 100 in order to efficiently transfer the heat generated from the heat generating device to the heating tank 100. It is known that the heat exchange fins 102 having L-shaped cross sections to be provided are arranged and rectangular heat exchange portions 104 having right-angle corner portions 103 at four corners are provided.

JP 2012-50730 A

  However, in the above-described liquid heating apparatus, for example, when the apparatus is driven, a combustion gas of 950 ° C. is flowed, and the front side of the bottom 101 near the heat generating device of the heating tank 100 is heated to about 300 ° C. via the fins 102. The thermal stress acting on the bottom 101 of the heating tank 100 around the right-angled corner 103 of the heat exchanging unit 103 may reach about 330 N / mm 2. For example, heating when the apparatus is driven and air cooling when the apparatus is stopped are repeated. As a result, the bottom 101 of the heating tub 100 is thermally expanded and contracted, and there is a possibility that distortion or the like due to the thermal expansion or contraction may occur in the bottom 101 of the heating tub 100 around the right-angled corner portion 103 of the heat exchanging portion 104 where thermal stress is concentrated. There was a problem.

  Therefore, there is a technical problem to be solved in order to suppress the occurrence of partial deformation or the like due to thermal stress concentration at the bottom of the heating tank around the corner of the heat exchange unit. Aims to solve this problem.

  The present invention proposes to achieve the above object, and the invention according to claim 1 is directed to a heating tank in which a liquid is stored, a burner installed below the heating tank, and the heating tank. In the liquid heating apparatus including a heat exchanging portion formed by a plurality of fins extending in the front-rear direction and fixed to the outer surface of the bottom portion, the fins are composed of a plurality of types having different lengths, and the plurality of types of fins Are arranged in order from the shortest length toward the center from the left and right sides of the heat exchanging portion, so that non-right angle corner portions are formed at the two corners on the front end side of the heat exchanging portion. A liquid heating apparatus configured to be formed is provided.

  According to this configuration, by providing the non-right angle corners at the two corners on the front end near the burner of the heat exchange unit where the temperature rise is large, heat is generated around the two corners on the front end side of the conventional rectangular heat exchange unit. Compared with a liquid heating device where stress tends to concentrate locally, the heat stress acting on the bottom of the heating tank around the two corners on the front end side of the heat exchange part is distributed throughout the non-right angle corner part. The deformation | transformation etc. resulting from the thermal-stress concentration of the bottom part of a heating tank in the front-end side two corner periphery can be suppressed.

  The invention according to claim 2 is formed by a heating tank in which a liquid is stored, a burner installed below the heating tank, and a plurality of fins extending in the front-rear direction and fixed to the outer surface of the bottom of the heating tank. In the liquid heating apparatus provided with the heat exchange unit, the fins are composed of a plurality of types having different lengths, and the plurality of types of fins from the left and right sides of the heat exchange unit toward the center, Provided is a liquid heating apparatus in which non-right angle corner portions are provided at two corners on the front end side and two rear end sides of the heat exchanging portion by arranging them in order from those having a short length.

  According to this configuration, the thermal stress is locally generated around the four corners of the conventional rectangular heat exchange portion by providing the non-right angle corner portions at the front end side two corners and the rear end side two corners, respectively. Compared with the liquid heating device that tends to concentrate on the heat exchanger, the heat stress acting on the bottom of the heating tank around the two corners on the front end side and the two corners on the rear end side of the heat exchange part is distributed throughout the non-right angle corner part. The partial deformation | transformation etc. resulting from the thermal stress concentration of the bottom part of a heating tank in the front-end side two corners and the rear-end side two corner periphery vicinity of a part can be suppressed.

  According to a third aspect of the invention, in addition to the configuration of the first or second aspect of the invention, the non-perpendicular corner portion of the heat exchanging portion is oblique with respect to the longitudinal direction of the fin or the center of the heat exchanging portion. A liquid heating device is provided which is formed in a convex shape outward from the outer side.

  According to this configuration, in order to avoid thermal stress from concentrating on the bottom of the heating tank around the non-right-angled corner portion formed in a slanted line shape or an outwardly convex shape, a partial portion of the bottom of the heating tank is used. Deformation and the like can be further suppressed.

  According to a fourth aspect of the present invention, in addition to the configuration of the first aspect of the present invention, a liquid heating device in which each fin has a notch for absorbing thermal expansion and contraction. provide.

  According to this configuration, since the rigidity of the fin is reduced by the amount of the notch provided in the fin, even if each fin of the heat exchange unit and the bottom of the heating tank are thermally expanded with different displacement amounts, respectively. The fin bends in response to the thermal expansion of the bottom of the heating tank and absorbs the difference in displacement between the fin and the bottom of the heating tank, so that inadvertent tension between the fin and the bottom of the heating tank Generation of stress can be suppressed.

  According to a fifth aspect of the present invention, in addition to the configuration of the fourth aspect of the invention, each of the fins stands on a fixing surface fixed to the outer periphery of the bottom of the heating tank, and on both side edges in the width direction of the fixing surface. Provided is a liquid heating apparatus which is formed in a U-shaped cross section composed of a provided side wall surface, and the notch is opened in the side wall surface.

  According to this configuration, since the rigidity of the fin is reduced by the amount of the notch portion provided on the side wall surface of the fin, the side wall surface expands in a fan shape so that the notch portion of the fin is widened, and the fin is Since it becomes easy to bend according to expansion | swelling, generation | occurrence | production of the tensile stress between the sticking surface of a fin and the bottom part of a heating tank can further be suppressed.

  According to a sixth aspect of the invention, in addition to the configuration of the fourth aspect of the invention, the fins stand on the fixing surface fixed to the outer periphery of the bottom of the heating tank and the side edges in the width direction of the fixing surface. The liquid heating device is provided with a side wall surface provided, and the notch is opened in the fixing surface.

  According to this configuration, since the adhesion area between the fin fixing surface and the bottom of the heating tank is reduced by the amount of the cutout portion provided on the fin fixing surface, the fin can easily follow the thermal expansion of the bottom of the heating tank. Thus, it is possible to further suppress the generation of tensile stress between the fixing surface of the fin and the bottom of the heating tank.

  According to a seventh aspect of the invention, in addition to the configuration of the fourth aspect of the invention, each of the fins stands on a fixing surface that is fixed to the outer periphery of the bottom of the heating tank, and a lateral edge of the fixing surface. The liquid heating apparatus is provided with a side wall surface provided, and the notch is opened across both the fixing surface and the side wall surface.

  According to this configuration, since the bonding area between the fin and the heating tank is reduced and the rigidity of the fin is reduced by the amount of the notch provided across the fixing surface and the side wall surface of the fin, the fin is the bottom of the heating tank. It becomes easy to follow the thermal expansion of this, and generation | occurrence | production of the tensile stress between the sticking surface of a fin and the bottom part of a heating tank can further be suppressed.

  According to the first aspect of the present invention, since the thermal stress acting on the bottom of the heating tank around the front corners at the two corners of the heat exchanging portion is distributed throughout the non-right angle corner portion, It is possible to suppress partial deformation, cracking, and the like due to thermal stress concentration at the bottom of the tank.

  The invention according to claim 2 is to disperse the thermal stress acting on the bottom of the heating tank around the two corners of the front end side and the rear end side of the heat exchange part over the entire non-right angle corner part. Partial deformation caused by thermal stress concentration at the bottom of the heating tank around the two corners and the two corners on the rear end side can be suppressed.

  In addition to the effects of the invention described in claim 1 or 2, the invention described in claim 3 reliably disperses that the thermal stress concentrates on the bottom of the heating tank around the non-right angle corner of the heat exchange part. Partial deformation of the bottom of the heating tank can be further suppressed.

  In addition to the effect of the invention according to any one of claims 1 to 3, the invention described in claim 4 is configured such that when the heating tank and the fin are thermally expanded, the fin bends and the bottom of the fin and the heating tank Since the difference in the amount of displacement between the fins and the bottom of the heating tank is absorbed, the occurrence of inadvertent tensile stress can be suppressed.

  In addition to the effect of the invention of claim 4, the invention according to claim 5 is such that the side wall surface of the fin is easily fan-shaped and can easily follow the thermal expansion of the bottom of the heating tank. Generation | occurrence | production of the tensile stress between the bottom parts of can be further suppressed.

  In addition to the effect of the invention described in claim 4, the invention described in claim 6 reduces the bonding area between the fin fixing surface and the bottom of the heating tank, so that the gap between the fin fixing surface and the heating tank bottom is small. It is possible to further suppress the generation of tensile stress in

  According to the seventh aspect of the invention, in addition to the effect of the fourth aspect of the invention, the bonding area between the fin fixing surface and the bottom of the heating tank is reduced and the rigidity of the fin is reduced. Generation | occurrence | production of the tensile stress between the bottom parts of a tank can further be suppressed.

The perspective view of the fryer which is one Example of this invention 1 is a partially cutaway side view showing a part of the fryer of FIG. (A) is the figure which looked at the outer surface of the heating tank of the fryer shown in FIG. 1 from the downward direction, (b) is the figure which looked at the heat exchange part shown in FIG. 3a from the longitudinal direction of the fin. The IVA part and IVB part enlarged view of FIG. 3a. Exploded view of fins composing heat exchanger FIG. 5 is a development view showing a first modification of the fin shown in FIG. FIG. 5 is a development view showing a second modification of the fin shown in FIG. (A) is the figure which looked at the outer surface of the heating tank of the conventional fryer from the downward direction, (b) is the figure which looked at the heat exchange part shown to FIG. 8a from the longitudinal direction of the fin. The side view of the fin which comprises the heat exchange part shown to FIG.

  The present invention provides a heating tank in which liquid is stored in order to suppress the occurrence of partial deformation or the like caused by thermal stress concentration at the bottom of the heating tank around the corner of the heat exchange part. A liquid heating apparatus comprising: a burner installed below the heating tank; and a heat exchanging portion formed by a plurality of fins extending in the front-rear direction and fixed to the outer surface of the bottom of the heating tank. The fins are composed of a plurality of types having different lengths, and the plurality of types of fins are arranged in order from the shortest to the center from both the left and right sides of the heat exchange section. Thus, the liquid heating device is configured so that non-right-angled corner portions are formed at two corners on the front end side of the heat exchange portion.

Hereinafter, a liquid heating apparatus according to a first embodiment of the present invention will be described with reference to the drawings.
A direct heating type fryer 1 as a liquid heating apparatus according to the present embodiment includes a heating tank 3 that is opened above a housing 2 and stores oil, as shown in FIGS. 3 and a heat exchanging unit 5 in which a plurality of fins 6 extending in the front-rear direction are disposed on the outer surface 31 s of the bottom 31 of the heating tank 3.

  At the lower part of the housing 2, there are provided leg portions 21 for installation on a frame (not shown) installed on the floor surface of a kitchen or the like. An operation panel 22 for operating the fryer 1 is provided on the front surface of the housing 2. Furthermore, an oil drain valve 32 for draining oil from the heating tank 3 is attached from the heating tank 3 toward the front surface of the housing 2.

  Below the heating tank 3, a combustion chamber 24 that houses a burner 4 provided with a combustion gas outlet (not shown) facing the outer surface 31 s of the bottom 31, and a combustion chamber 24 that communicates with the combustion chamber 24 and the heating tank 3. A combustion passage 25 that extends from the front side to the rear side, that is, from the left side to the right side of FIG. 2 and is surrounded by the outer surface 31s of the bottom 31 as an upper wall is provided.

  As shown by an arrow G in FIG. 2, the combustion gas emitted from the burner 4 heats the heating tank 3 through the heat exchange unit 5 when passing through the combustion passage 25, and stands on the back surface of the housing 2. It passes through an exhaust path 27 in the provided back guard 26 and is discharged from the exhaust port 28 to the outside of the fryer 1.

  As shown in FIGS. 3A and 3B, the fins 6 are three types of fins 6 </ b> A, 6 </ b> B, and 6 </ b> C having different lengths, and the heat exchanging unit 5 is provided at the bottom 31 of the heating tank 3. Fins 6A, 6B, and 6C are arranged on the outer surface 31s in order from the shortest length toward the center from the left and right sides of FIG. The fin 6 may be SUS430 having a low thermal expansion coefficient or SUS304 excellent in high temperature resistance.

The heat exchanging portion 5 includes a non-right-angled corner portion R1 formed in a step shape at the end portions of the fins 6A, 6B, and 6C at the front end side, that is, at the two corners on the lower side of FIG.
As a result, the thermal stress acting on the bottom 31 of the heating tank 3 around the two corners on the front end side of the heat exchanging unit 5 is distributed to the ends of the fins 6A, 6B, 6C. Compared with the case where the thermal stress acting around the corner portion is about 330 N / mm 2, in the thermal stress analysis using the fryer 1 according to the present embodiment, the thermal stress acting on the non-right angle corner portion R 1 is as shown in FIG. As shown at measuring points 1 to 8 in the middle, it is reduced to 68 to 207 N / mm 2, and is partially due to thermal stress concentration at the bottom 31 of the heating tank 3 around the two corners on the front end side of the heat exchange unit 5. Deformation and the like can be suppressed.

Moreover, the heat exchange part 5 is provided with the non-right-angled corner part R2 formed in the back end side, ie, the two corners of FIG.
As a result, in the same manner as the front end side of the heat exchanging unit 5, the thermal stress acting on the bottom 31 of the heating tank 3 around the two corners on the rear end side of the heat exchanging unit 5 is dispersed throughout the non-right angle corner R2. Cracks due to thermal stress concentration of the bottom 31 of the heating tank 3 in the vicinity of the two corners on the rear end side of the exchange unit 5 can be suppressed.

In addition, about the shape of non-right-angle corner part R1, R2, it forms in step shape like a present Example, and the edge part of the fin 6 swells diagonally or outward with respect to the longitudinal direction of the fin 6. And may be formed in a diagonal shape with respect to the longitudinal direction of the fin 6 or a convex shape outward from the center in the heat exchange part 5.
This avoids concentrating the thermal stress acting on the bottom 31 of the heating tank 3 around the non-right-angled corners R1 and R2 of the heat exchanging part 5 to further crack the bottom 31 of the heating tank 3. Can be suppressed.

  Each fin 6 is formed in a U-shaped cross section, and as shown in the development view of FIG. 5, a fixing surface 61 fixed to the outer surface 31 s of the bottom 31 of the heating tank 3 and the width of the fixing surface 61. And side wall surfaces 62 standing from both side edges in the direction.

  The side wall surface 62 is formed to have a gradually reduced width from the vicinity of the center of the fin 6 toward the front, that is, from the vicinity of the center of the sheet of FIG. 5 to the right. As a result, the short side of the side wall surface 62 is attached to the side closer to the burner 4, and the long side is attached to the far side from the burner 4, thereby securing the heat receiving area of the combustion gas, and in the longitudinal direction of the side wall surface 62. The temperature gradient before and after is relaxed, and the entire bottom 31 of the heating tank 3 is easily heated uniformly.

The side wall surface 62 of each fin 6 is provided with an elliptical side notch 63 that extends in the width direction of the fin 6 and opens at the edge of the side wall surface 62.
Moreover, the substantially circular center notch 64 is provided so as to straddle both the fixing surface 61 and the side wall surface 62 of the fin 6.
The two side cutouts 63 and the two central cutouts 64 arranged in the width direction of the fin 6 are continuously arranged at substantially equal intervals in the longitudinal direction of the fin 6.

  As a result, the rigidity of the fin 6 is lowered by the amount of the side notch 63 and the center notch 64 provided in the fin 6, and the temperature of each fin 6 of the heat exchange part 5 and the bottom 31 of the heating tank 3 increases. Accordingly, even when the thermal expansion is performed with different displacement amounts, the fins 6 bend according to the thermal expansion of the bottom portion 31 of the heating tank 3, and the displacement amount between the fins 6 and the bottom portion 31 of the heating tank 3 is reduced. While absorbing the difference, the side wall surface 62 of the fin 6 is likely to spread in a fan shape in the longitudinal direction so as to be widened by the side notch 63, and it is easy to follow the thermal expansion of the bottom 31 of the heating tank 3. Inadvertent generation of tensile stress between the bottom 31 of the heating tank 3 can be suppressed.

  Furthermore, since the bonding area between the fin 6 and the heating tank 3 is reduced by the amount of the central notch 64 straddling the fixing surface 61 and the side wall surface 62 of the fin 6, the fin 6 has the bottom 31 of the heating tank 3. This makes it easier to follow the thermal expansion of the material, and can further suppress the generation of tensile stress between the fixing surface 61 of the fin 6 and the bottom 31 of the heating tank 3.

  Next, the fin 7 which is 2nd Example of the fin 6 is demonstrated based on the expanded view of FIG. Here, about the member same as the fin 6 of 1st Example mentioned above, the overlapping description is abbreviate | omitted by attaching | subjecting the code | symbol of 70 series.

  The fin 7 according to the present embodiment includes a fixing surface 71 and side wall surfaces 72 provided on both side edges of the fixing surface 71. In addition, about the cross-sectional shape of the fin 7 which concerns on a present Example, even if it is an L-shaped cross section which provided only one side wall surface 72, the height of the side wall surfaces 72 and 72 differs, respectively. It doesn't matter.

The central notch 74 of the fin 7 is formed in an elliptical shape between the side wall surfaces 72, 72 provided on both sides of the fixing surface 71.
Further, the side cutout 73 of the fin 7 is opened in an elliptical shape on the side wall surface 72.
The central notch 74 and the two side notches 73 arranged in the width direction of the fin 7 are continuously arranged at substantially equal intervals over the longitudinal direction of the fin 7.

  As a result, similar to the effect of the fin 6 used in the first embodiment described above, the rigidity of the fin 7 is reduced by the amount of the side notch 73 and the center notch 74 provided in the fin 7, and the fin 7 Since the bonding area between the fin 7 and the heating tank 3 is small by the amount of the central notch 74, the fins 7 of the heat exchange part 5 and the bottom 31 of the heating tank 3 are heated with different displacement amounts as the temperature rises. Even in the case of expansion, the fins 7 bend in accordance with the thermal expansion of the bottom 31 of the heating tank 3 to absorb the difference in displacement between the fins 7 and the bottom 31 of the heating tank 3 and the heating tank 3. Since it becomes easy to follow the thermal expansion of the bottom part 31 of this, generation | occurrence | production of the excessive tensile stress between the fin 7 and the bottom part 31 of the heating tank 3 can be suppressed.

  Next, the fin 8 which is 3rd Example of the fin 6 is demonstrated based on the expanded view of FIG. Here, about the same member as the fin 6 of 1st Example mentioned above, the overlapping description is abbreviate | omitted by attaching | subjecting the code | symbol of the 80s.

  As shown in the development view of FIG. 7, the fin 8 extends over the side wall surfaces 82, 82, and a circular central circular notch 84 A provided so as to straddle both the fixing surface 81 and the side wall surface 82 of the fin 8. A central horizontally long cut portion 84B formed in a long hole shape long in the width direction of the fin and a central vertical cut portion 84C formed in a long hole shape long in the longitudinal direction of the fin 8 on the fixing surface 81 are provided.

  Thereby, in addition to the effect which the fin 6 used by 1st Example mentioned above show | plays, only the part which provided the center notch part 84C in the fixing surface 81 of the fin 8 and the bottom part 31 of the heating tank 3 are provided. And the rigidity of the fin 8 further decreases, so that the fin 8 can easily follow the thermal expansion of the bottom 31 of the heating tank 3, and the fixing surface 81 of the fin 8 and the bottom 31 of the heating tank 3 It is possible to further suppress the generation of tensile stress between the two.

  In the fryer 1 using the fins 8, when the fins 8 are brazed to the outer surface 31 s of the heating tank 3, the number of the heating tanks 3 that can be brazed at once in a brazing heating furnace is smaller than that of the conventional case. ), The production efficiency of the heating tank 3 can be improved. In other words, when fins are brazed to a heating tank, they are housed in a brazing furnace, and a conventional liquid heating apparatus tilts an inverted heating tank diagonally in the heating furnace. In this state, brazing is performed by letting a wax placed between adjacent fins flow down between the fixing surface of the fin and the outer surface of the heating tank, whereas in the fryer 1 using the fins 8, heating is turned upside down. In a state where the tank 3 is horizontal in the heating furnace, the brazing disposed on the fixing surface 81 can be brazed by pouring between the outer surface 31s of the heating tank 3 and the fixing surface 81 of the fin 8 through the central notch 84C. Therefore, space saving of the heating tank 3 in the heating furnace is realized as much as the heating tank 3 can be accommodated in the heating furnace in a horizontal state, and the number of heating tanks 3 that can be brazed at a time is increased. 3 production efficiency can be improved.

  In this embodiment, a direct heating type fryer using a gas burner is illustrated as the liquid heating device, but a direct heating type frying machine may be used.

  The present invention can be variously modified without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

DESCRIPTION OF SYMBOLS 1 ... Flyer 2 ... Case 3 ... Heating tank 4 ... Burner 5 ... Heat exchange part 6 ... Fin 61 ... Adhering surface 62 ... Side wall surface 63 ... Side notch 64 ... Central notch 7 ... Fin 71 ... Fixing surface 72 ... Side wall surface 73 ... Side notch 74 ... Center notch 8 ... Fin 81・ ・ Fixed surface 82 ・ ・ ・ Side wall surface 83 ・ ・ ・ Side cutout 84A ・ ・ ・ Center circular cutout 84B ・ ・ ・ Center horizontal cutout 84C ・ ・ ・ Center vertical cutout R1, R2 ・ ・ ・ Non-right angle Corner part 100 ... Heating tank 101 ... Bottom part (of heating tank) 102 ... Fin 103 ... Right angle corner part 104 ... Heat exchange part

Claims (7)

A heating tank in which a liquid is stored; a burner installed below the heating tank; and a heat exchange part formed by a plurality of fins extending in the front-rear direction and fixed to the outer surface of the bottom of the heating tank. In the liquid heating device,
The fin is composed of a plurality of types having different lengths,
The plurality of types of fins are arranged so as to be arranged in order from the shortest length from both the left and right sides of the heat exchanging portion toward the center, so that the fins are arranged at two corners on the front end side of the heat exchanging portion. A liquid heating apparatus characterized in that a non-right angle corner is formed. A heating tank in which a liquid is stored; a burner installed below the heating tank; and a heat exchange part formed by a plurality of fins extending in the front-rear direction and fixed to the outer surface of the bottom of the heating tank. In the liquid heating device,
The fin is composed of a plurality of types having different lengths,
The plurality of types of fins are arranged so as to be sequentially arranged from a type having a short length from both the left and right sides of the heat exchange unit toward the center, so that two corners on the front end side of the heat exchange unit are arranged. And a non-right angle corner at two corners on the rear end side.   The non-right-angled corner portion of the heat exchange part is formed in a diagonal shape with respect to the longitudinal direction of the fin or a convex shape outward from the center in the heat exchange part. 3. The liquid heating apparatus according to 2.   The liquid heating apparatus according to claim 1, wherein each fin has a notch for absorbing thermal expansion and contraction. Each of the fins is formed in a U-shaped cross section composed of a fixing surface fixed to the outer periphery of the bottom of the heating tank and side wall surfaces standing on both side edges in the width direction of the fixing surface,
The liquid heating apparatus according to claim 4, wherein the notch is opened in each of the side wall surfaces. Each of the fins comprises a fixing surface fixed to the outer periphery of the bottom of the heating tank, and a side wall surface erected on a side edge in the width direction of the fixing surface,
The liquid heating apparatus according to claim 4, wherein the notch is formed in the fixing surface. Each of the fins comprises a fixing surface fixed to the outer periphery of the bottom of the heating tank, and a side wall surface erected on a side edge in the width direction of the fixing surface,
The liquid heating apparatus according to claim 4, wherein the cutout portion is opened across both the fixing surface and the side wall surface.

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