JP2000245628A - Heat exchanger and combustion type kitchen equipment using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger which is good in heat transfer efficiency and is adequate for use in kitchen equipment. SOLUTION: An intermediate plate 6 is disposed in a heat exchanger 3 having a circular shape in cross section and the heat of the heated intermediate plate 6 is transferred via bent parts 7 to the inside wall of the heat exchanger 3 to increase the temperature of the inside wall of the heat exchanger 3 and, therefore, the heat transfer efficiency of the heat exchanger is improved. The length (not inclusive of the bent parts 7) elongating the intermediate plate 6 is longer than the bore of the heat exchanger 3. The intermediate plate 6 is, therefore, formed to an S shape and is built in. The bent parts 7 are pressed to the inside wall of the heat exchanger 3 by the elastic force generated at this time. The adhesion property of the bent parts 7 and the inside wall of the heat exchanger 3 is thereby improved and the heat transfer efficiency is improved. The length of the intermediate plate 6 is prolonged and, therefore, a heat receiving area may be made larger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger for transmitting the heat of a flame and a combustion gas flowing inside to a heated object such as water or oil outside and a kitchen machine using the same.

[0002]

2. Description of the Related Art Conventionally, water,
Kitchen machines that heat oil and the like are used. FIG. 6 shows a schematic structure of a commercial fryer as an example. In FIG. 6, cooking oil is put in an oil tank 11, in which cooking of fries, tempura and the like is performed. The combustion flame and the combustion gas of the gas burner 12 are discharged to the outside through the heat exchanger 13 and exchange heat with the cooking oil in the oil tank 11 in the heat exchanger 13 to heat the cooking oil. The edible oil exceeding the usage limit is discharged from the oil drain port 14, received by the oil can 15, and carried out.

[0003] In the past, in such commercial fryers, the heat exchanger was composed of a large number of straight tubes, and the heat transfer area could be increased. However, oil tank 1
When a large number of straight pipes are arranged in one, it becomes an obstacle and it is difficult to clean the lower part of the oil tank 11. As a countermeasure, in a commercial fryer as shown in FIG. 6, the heat exchanger 13 is folded back in the middle to make it thicker, and the heat exchanger 13 is arranged with a small number thereof and is spaced apart in the horizontal direction. The lower part of the can be cleaned.

[0004]

However, in a commercial fryer having a structure as shown in FIG. 6, the heat transfer area is smaller than that in a case where a large number of straight pipes are arranged in an oil tank, so that the thermal efficiency is low. There is a problem of worsening. In addition, in order to secure a space for cleaning, heat radiation fins cannot be provided outside the heat exchanger 13, and it is difficult to increase the thermal efficiency from this aspect as well. In addition, heat exchanger 1
3 has a U-shaped shape, so that there is a problem in that the pressure loss is large and there is a limit in increasing the thermal efficiency by optimizing the combustion state.

The present invention has been made in view of such circumstances, and has a good heat transfer efficiency and is suitable for use in a kitchen machine having a structure as shown in FIG. 6, and a combustion apparatus using the same. It is an object to provide a type kitchen machine.

[0006]

The first means for solving the above-mentioned problems is a heat exchanger for transmitting the heat of the flame and the combustion gas flowing inside to a heated object such as water or oil outside. There, in the cross-sectional shape perpendicular to the longitudinal direction, an intermediate plate is provided between a part of the inner wall and another part of the inner wall,
The intermediate plate is provided over the entire length or a part of the heat exchanger (claim 1).

In this means, an intermediate plate is provided between a part of the inner wall of the heat exchanger and the other part of the inner wall, and the intermediate plate is heated by the flame and the combustion gas. Heat is transferred to the inner wall of the heater. Therefore, the temperature of the inner wall of the heater can be increased, and the amount of heat transferred to the object to be heated increases, thereby improving the thermal efficiency.

[0008] A second means for solving the above problems is as follows.
In the first means, the intermediate plate has a cross section perpendicular to the longitudinal direction of the heat exchanger, both ends of which are bent, and the bent portion is formed on an inner surface of the heat exchanger.
It is characterized by being in contact by elastic force (claim 2).

In this means, since the bent portions at both ends of the intermediate plate surely come into contact with the inside of the heat exchanger, the heat from the intermediate plate can be reliably transmitted to the inner wall of the heat exchanger. it can. Further, since this contact is performed by the elastic force, it is easy to insert the intermediate plate into the heat exchanger.

[0010] A third means for solving the above problems is as follows.
In the first means or the second means, a length of the intermediate plate is longer than a length connecting a part of the inner wall and another part in a cross-sectional shape perpendicular to a longitudinal direction of the heat exchanger. The present invention is characterized in that it is elongated (claim 3).

In the present means, the length of the intermediate plate is longer than the length connecting the part of the inner wall and the other part in the cross-sectional shape perpendicular to the longitudinal direction of the heat exchanger. When the plate is inserted into the heat exchanger, it is inserted in a folded shape. Thereby, it is possible to apply elastic force for contacting the inner wall of the heat exchanger to the bent portions formed at both ends. Further, by increasing the length of the intermediate plate, the heat transfer area from the flame and the combustion gas to the intermediate plate can be increased, and the thermal efficiency can be improved.

A fourth means for solving the above-mentioned problem is as follows.
Any of the first means to the third means, wherein the intermediate plate is provided with a means for making a flow of a combustion gas flowing in the heat exchanger a turbulent flow. (Claim 4).

In this means, since the intermediate plate is provided with means for making the flow of the combustion gas flowing in the heat exchanger into a turbulent flow, the flow of the combustion gas becomes turbulent, whereby the inner wall of the heat exchanger is formed. The heat transfer coefficient between the gas and the combustion gas is improved.
Therefore, a heat exchanger having high heat efficiency can be obtained.

A fifth means for solving the above-mentioned problems is as follows.
The fourth means, wherein the means for making the flow of the combustion gas flowing through the heat exchanger a turbulent flow is a part in which the intermediate plate is partially cut and the cut part is bent. (Claim 5).

For example, a U-shaped notch is provided in the intermediate plate, and a bent portion thereof is provided to provide an obstruction plate for the gas flow. Therefore, the gas flow is made turbulent at the portion of U.

A sixth means for solving the above-mentioned problem is as follows.
The fourth means, wherein the means for causing the flow of the combustion gas flowing in the heat exchanger to be a turbulent flow, is an unevenness provided on the intermediate plate (Claim 6). .

The intermediate plate is pressed so that the intermediate plate itself has irregularities, or another member is fixed to form a convex portion and a portion where the member is not provided a concave portion. By doing so, irregularities are provided on the intermediate plate. The flow of the combustion gas is turbulent by the irregularities.

A seventh means for solving the above-mentioned problems is as follows.
Any one of the first means to the sixth means, wherein the inside of the heat exchanger is black (Claim 7).

In this means, since the inside of the heat exchanger is made black by painting or the like, the radiant heat transfer from the flame is increased, and a heat exchanger with high heat efficiency can be obtained.

Eighth means for solving the above-mentioned problem is:
A kitchen machine for heating a body to be heated such as water or oil by burning fuel, comprising a heat exchanger according to any of the first to seventh means, wherein the heat exchanger is A combustion-type kitchen machine (claim 8), characterized by being folded back.

As described above, all of the heat exchangers according to the first to seventh means have a high heat transfer efficiency, and therefore, it is particularly effective to use the heat exchanger of the type that is folded back halfway. is there. In addition, since the intermediate plate has a simple structure, the pressure loss caused by the provision of the intermediate plate is small, and even in this aspect, even if the intermediate plate is used in a folded heat exchanger, the adverse effect on the combustion performance is adversely affected. Less is.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same components as those of the apparatus are denoted by the same reference numerals, and the description thereof will not be repeated.

FIG. 1 is a diagram showing an outline of a commercial fryer according to an embodiment of the present invention. In FIG.
1 is an oil tank, 2 is a gas burner, 3 is a heat exchanger, 4 is an oil drain port, 5 is an oil can, and 6 is an intermediate plate.

Cooking oil is put in the oil tank 1 and cooking of fries, tempura and the like is performed in the oil tank. The combustion flame and the combustion gas of the gas burner 2 are discharged to the outside through the heat exchanger 3 and exchange heat with the cooking oil in the oil tank 1 in the heat exchanger 3 to heat the cooking oil. The edible oil exceeding the usage limit is discharged from the oil drain port 4, is received by the oil can 5, and is carried out to the outside. The heat exchangers 3 are provided in two rows in the horizontal direction, and a gap is provided between them, so that the lower part of the oil tank 1 can be cleaned through the gap. A burner may be provided separately for each heat exchanger 3 or two rows of heat exchangers 3.
May be provided in common. In the latter case, the exhaust gas passing through the heat exchanger 3 is guided to a common exhaust port, and is exhausted from the exhaust port.

The heat exchanger 3 is configured to be folded up and down, so that the heat transfer length is increased. An intermediate plate 6 according to the present invention is provided on the upper side. In the example shown in FIG. 1, the intermediate plate 6 is provided only on the upper side of the heat exchanger 3, but may be provided on the lower side.

FIG. 2 shows an example of a sectional shape of the intermediate plate 6. In FIG. 2, reference numeral 7 denotes a bent portion. The intermediate plate 6 is made of a plate having a thin cross section. The intermediate portion has an S-shape, and bent portions 7 are formed at both ends of the cross section.

FIG. 3 is a cross-sectional view in which the intermediate plate 6 is incorporated in the heat exchanger 3. In the case of FIG. 3, the heat exchanger 3 has a circular cross section, and the length of the extended intermediate plate 6 (not including the bent portion 7) is longer than the inner diameter of the heat exchanger 3. Therefore, the intermediate plate 6 is assembled in an S-shape, and the bent portion 7 is pressed against the inner wall of the heat exchanger 3 by the elastic force generated at that time. Therefore, the adhesion between the bent portion 7 and the inner wall of the heat exchanger 3 is increased, and the heat transfer coefficient is improved. Further, since the length of the intermediate plate 6 is increased, the heat receiving area can be increased.

The bent portion 7 itself has a radius of curvature larger than the radius of curvature of the inner wall of the heat exchanger 3.
If the intermediate plate 6 is made to contract when inserted into the heat exchanger 3, it has elasticity itself, the adhesion between the bent portion 7 and the inner wall of the heat exchanger 3 is increased, and the heat transfer coefficient is good. Become.

In this embodiment, the intermediate plate 6 is inserted into the heat exchanger 3 and fixed by utilizing the elasticity of the intermediate plate 6, so that the fixing method is easy and the The plate 6 can be easily removed.

In the present invention, the number of the intermediate plates 3 does not necessarily have to be one. A plurality of similar intermediate plates 3 may be arranged side by side in parallel, or may be placed in a heat exchanger as a cross-shaped intermediate plate. Such a shape also satisfies the configuration that “an intermediate plate is provided between a part of the inner wall and another part of the inner wall”.

FIG. 4 shows an example of the shape of the intermediate plate 6, and reference numeral 8 denotes a blade. The blades 8 are formed by cutting a part of the intermediate plate 6 into a U-shape and turning the cut parts alternately right and left around a part that is not cut so that the combustion gas The structure is such that it serves as a baffle for the flow. By inserting the intermediate plate 6 having such a shape into the heat exchanger 3, the flow of the combustion gas is made turbulent by the blades 8. Therefore, the heat transfer coefficient between the inner wall of the heat exchanger 3 and the combustion gas is improved, and the thermal efficiency is improved.

FIG. 5 shows another example of the shape of the intermediate plate 6, wherein 9a and 9b are uneven portions. That is, a part of the central portion of the intermediate plate 6 is bent into a curved shape by pressing, for example, and the concave and convex portions 9a and 9b which are alternately convex right and left are formed. In the figure, 9a is convex toward the front and 9b is convex behind. By inserting the intermediate plate 6 having such a shape into the heat exchanger 3, the flow of the combustion gas becomes uneven.
b causes turbulence. Therefore, the heat transfer coefficient between the inner wall of the heat exchanger 3 and the combustion gas is improved, and the thermal efficiency is improved.
Instead of providing the concave and convex portions 9a and 9b, convex portions are discretely provided on the left and right of the central portion of the intermediate plate 6 by discretely fixing other members, thereby generating a turbulent flow. Good.

In any of the above embodiments, the interior of the heat exchanger 3 including the intermediate plate 6 is preferably black. By doing so, the radiant heat transfer coefficient from the combustion flame to the heat exchanger 3 increases, and
Thermal efficiency is improved.

It is to be noted that providing such an intermediate plate is as follows.
This is particularly effective in a kitchen machine in which the heat exchanger 3 is folded halfway as shown in FIG. This is because in such a kitchen machine, it is particularly necessary to increase the thermal efficiency as described above. Also, since the intermediate plate has a simple structure,
This is particularly preferable because the pressure loss caused by the provision thereof is small, and even when used in a heat exchanger of a system that is folded back halfway, there is little adverse effect on combustion performance.

[0035]

As described above, according to the first aspect of the present invention, the intermediate plate is provided between a part of the inner wall of the heat exchanger and another part of the inner wall. Thermal efficiency is improved.

According to the second aspect of the invention, the heat from the intermediate plate can be reliably transmitted to the inner wall of the heat exchanger. Further, it is easy to insert the intermediate plate inside the heat exchanger.

According to the third aspect of the present invention, an elastic force for contacting the inner wall of the heat exchanger can be provided, and a heat transfer area from the flame and the combustion gas to the intermediate plate can be increased.

According to the fourth aspect of the present invention, the flow of the combustion gas becomes turbulent, thereby improving the heat transfer coefficient between the inner wall of the heat exchanger and the combustion gas.

According to the fifth and sixth aspects of the present invention, it is possible to reliably make the flow of the combustion gas turbulent.

In the invention according to claim 7, the radiant heat transfer from the flame is increased, and the thermal efficiency is improved.

In the invention according to the eighth aspect, it is particularly effective to improve the thermal efficiency, and since the thermal efficiency can be improved with a small pressure loss, the adverse effect on the combustion performance is small.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a commercial fryer which is an example of an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a cross-sectional shape of an intermediate plate.

FIG. 3 is a cross-sectional view showing a state where the intermediate plate shown in FIG. 2 is incorporated in a heat exchanger.

FIG. 4 is a diagram showing an example of the shape of an intermediate plate.

FIG. 5 is a view showing another example of the shape of the intermediate plate.

FIG. 6 is a schematic diagram showing the structure of a conventional commercial fryer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Oil tank 2 ... Gas burner 3 ... Heat exchanger 4 ... Oil drain port 5 ... Oil can 6 ... Intermediate plate 7 ... Bending part 8 ... Blade part 9a, 9b ... Uneven part

Claims (8)

[Claims] 1. The heat of the flame and combustion gas flowing inside is
A heat exchanger that transfers heat to an object to be heated such as water or oil on the outside, and an intermediate plate is provided between a part of the inner wall and another part of the inner wall in a cross-sectional shape perpendicular to the longitudinal direction. Wherein the intermediate plate is provided over the entire length or a part of the heat exchanger. 2. The heat exchanger according to claim 1, wherein both ends of the intermediate plate are bent in a cross-sectional shape perpendicular to the longitudinal direction of the heat exchanger, and the bent portion is formed by heat. A heat exchanger, wherein the heat exchanger is in contact with an inner surface of the exchanger by an elastic force. 3. The heat exchanger according to claim 1, wherein a length of the intermediate plate is equal to a part of the inner wall in a cross-sectional shape perpendicular to a longitudinal direction of the heat exchanger. A heat exchanger characterized by being longer than a length connecting other parts. 4. One of claims 1 to 3
Item 4. The heat exchanger according to Item 1, wherein the intermediate plate is provided with means for causing a flow of combustion gas flowing in the heat exchanger to be turbulent. 5. The heat exchanger according to claim 4, wherein the means for causing the flow of the combustion gas flowing in the heat exchanger to be turbulent comprises:
A heat exchanger, wherein a part of the intermediate plate is cut out, and the cut-out part is bent. 6. The heat exchanger according to claim 4, wherein the means for causing the flow of the combustion gas flowing in the heat exchanger to be turbulent includes:
A heat exchanger, wherein the heat exchanger is an uneven surface provided on the intermediate plate. 7. One of claims 1 to 6
Item 4. The heat exchanger according to Item 1, wherein the inside of the heat exchanger is black. 8. A kitchen machine for heating an object to be heated such as water or oil by burning fuel, comprising a heat exchanger according to any one of claims 1 to 7. A combustion type kitchen machine characterized in that the heat exchanger is folded back halfway.