JP2000220971A - Plate type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plate type heat exchanger which comprises a small number of components and can be fabricated and assembled at low cost and moreover has a high heat exchanging function. SOLUTION: A plate 4, wherein recesses and protrusions are formed and an opening 7 is provided on each of the opposite ends thereof, is superposed on another plate 4 to form a heat exchange element 2. A plurality of elements 2 are stacked one on another to form the plate type heat exchanger. The plate 4 has contact parts 9, 6a, of 1-10 mm, on the peripheral edge of the plate and the opening 7, respectively, for contact with another plate, and each of the contact parts is inclined at an angle α, β of about 1-8 deg. with respect to the contact surface. If two plates are stacked, only the peripheral edges of the plates and openings contact with one another, and if forces are applied onto the plates until the recesses and protrusions contact with one another, the peripheries of the plates and the contact parts of the openings are brought into surface contact, and the peripheries of the plates and the contact parts of the openings are soldered to one another to form a single body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate heat exchanger, and in particular, at least one fluid is low-pressure steam, such as an evaporator, a low-temperature regenerator, or a condenser of a refrigerator using a low-pressure refrigerant. More particularly, the present invention relates to a plate heat exchanger in which plates are stacked and two fluids alternately flow between the plates to exchange heat.

[0002]

2. Description of the Related Art FIG. 8 is a sectional view of a conventional plate type heat exchanger. In FIG. 8, the heat exchanger is formed by stacking two plates 4a and 4b having openings 7 at both ends so as to form a space R1 therein, and sealing the peripheral portion to form a heat exchange element 2. The heat exchange element 2 is overlapped and connected so that the openings 7 communicate with each other to form a heat exchange structure. The heat exchange structure is accommodated inside the shell, and a fluid is flowed into and out of the heat exchange element 2. And heat exchange with each other. In the space R1 inside the heat exchange element 2, a wave-like or fin-like plate 20 is attached in order to increase the strength of the plate and disturb the flow to promote heat exchange. The upper and lower openings 7 are formed to protrude into a cylindrical shape having a size that can be fitted to each other.

In this type of heat exchanger, the inlet and outlet of the first fluid are connected to the opening 7, and the first fluid flows through the respective heat exchange elements 2 in parallel as shown by arrows, while The second fluid flows from the inlet / outlet of the second fluid provided in the shell to the outer space R2 of the heat exchange element 2.
Since the entrance to the outer space can be made wider than the entrance to R1, it is possible to cope with a fluid having a large specific volume with low-pressure steam. Also, depending on the shape of the irregularities, the external space R
2 can be made wider than the internal space R1, so that even low pressure steam can be handled. When manufacturing such a heat exchanger, first, the turbulent plate 20 is placed on the upper plate 4a.
Are mounted and positioned, the lower plate 4b is overlapped, and the peripheral edge is turned back to be joined. Next, the heat exchange elements are connected by fitting the cylindrical openings 7 to assemble the heat exchange structure 3, which is further assembled in the shell. In such a conventional technique, three parts are required to constitute the heat exchange element 2, and there is a problem that the production and management of the parts and labor and cost are required.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and has a small number of parts, can reduce manufacturing and assembly costs, and has a high heat exchange function. It is an object to provide a plate heat exchanger.

[0005]

In order to solve the above-mentioned problems, according to the present invention, plates having irregularities and provided with openings at both ends are superposed as a set of two plates to form one heat exchange element. The heat exchange element is formed by superposing a plurality of the heat exchange elements, a space between two plates forming the heat exchange element is used as a first fluid passage, and a space between the heat exchange element and the element is the first fluid. A plate-type heat exchanger in which a plate serves as a heat transfer surface for both fluids as a passage for another fluid (second fluid) having a heat exchange relationship with the fluid, wherein the plate has a length of 1 to 10 mm at the plate periphery and opening Another contact portion with the plate, the contact portion has an inclination of about 1 to 8 degrees with respect to the contact surface, and when the plates are stacked as a pair,
When only the peripheral portions are in contact with each other and a force is applied and pressed until the uneven portions of the two plates are in contact with each other, the peripheral contact portions are deformed, and the entire peripheral contact portions are in surface contact with each other. When the heat exchange element and the element are overlapped with their openings aligned, only the periphery of the opening comes into contact, and pressing is performed by applying force until the irregularities of the plate between the heat exchange elements come into contact with each other.
A plate-type heat exchanger characterized in that the contact portion on the periphery of the opening is deformed so that the contact portion on the periphery of the entire opening is in surface contact.

In the plate heat exchanger, all the plates are preferably brazed and integrated at the peripheral portion of the plate or at a contact portion of the opening, and the unevenness of the plate is oblique in one direction. In addition, the irregularities of the plate are spot-like irregularities such as a circular cross section, and when a heat exchange element is configured, the height of the convex side can be larger than the depth of the concave side. . Further, the plate is preferably raised so that one shape of the openings at both ends enters the other opening when the plates are overlapped.

[0007]

Next, the present invention will be described in detail.
According to the present invention, two plates having irregularities are overlapped so as to form a space inside, and the peripheral edges and the openings (fluid ports) at both ends are lightly contacted over the entire periphery when they are simply overlapped (line contact is made). ), When mosquito is added in the overlapping direction, the shape of the contact portion changes to form surface contact, and until the irregularities come into contact, mosquito is added and the contact surface becomes large, and the peripheral edge is formed by brazing (phrasing). It has a shape suitable for sealing. That is, in the case of brazing, brazing is performed while adding power to bring the plates into close contact with each other. However, when the power is added, the peripheral portion becomes parallel, and the unevenness of the plate comes into contact, which is preferable.

[0008] When the two plates as described above are overlapped with the brazing material placed (painted) on the portions to be contacted, a fluid flow path is formed between the spaces from the openings formed at both ends of the plates. A desired number of heat exchange elements are formed, the desired number of the heat exchange elements are overlapped with each other so that the openings communicate with each other, and the heat exchange elements and the heat exchange elements are brazed while adding power in the overlapping direction. The plate-type heat exchanger of the present invention is formed by the close contact. With such a configuration, a flow path bent by unevenness is formed inside and outside the heat exchange element composed of one type (or two types) of plates, and the heat exchanger has an efficient heat exchange function.

In the present invention, in addition to the brazing (phrasing), a case in which a gasket is inserted therebetween to add power from the outside or a case in which the gasket is sealed by welding is included. In the case of welding or brazing, the plates are overlapped and joined while adding power in the overlapping direction, but if the peripheral parts are free and parallel, the peripheral parts tend to open when adding the power, In particular, in the case of brazing, the strength of the peripheral portion is extremely reduced. In the present invention, the above-mentioned plates are superimposed on each other with a wax placed between the contact portions and / or the contact surfaces, and heated in a furnace and brazed all at once while adding power (with a weight) in the laminating direction. Thereby, the heat exchange structure is manufactured in one step, and the working steps are greatly simplified.

The unevenness of the plate of the present invention can be formed as a wavy pattern extending in a predetermined direction, and a complicated two-dimensionally bent channel can be formed with a relatively simple configuration. Further, the cross section of the irregularities can be a plate having spot-like irregularities such as a circle, and when superposed, the size of the external space and the internal space can be changed, so that a very low-pressure steam Can also be accommodated.
Furthermore, by providing a swing at one of the openings at both ends of the plate, positioning is simplified by fitting the openings at the time of superposition. Thus, the two-dimensional positioning of the plates is naturally performed only by overlapping the plates, thereby simplifying the manufacturing process.

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows the entire structure of a plate-type heat exchanger, in which a heat exchange structure 3 in which three heat exchange elements 2 are connected is mounted in a shell 1 extending in a longitudinal direction. As shown in FIG. 2 (a), when two plates 4 having a corrugated pattern are naturally superimposed on each other, the heat exchange element 2 makes line contact over the entire periphery thereof, while one opening is formed. 7 is in line contact with the next heat exchange element 2 'at the opening contact portion 6a. When a force (usually a weight) is added in the overlapping direction, as shown in FIG. 2B, a space R1 is formed by the contact of the unevenness of the wavy pattern, and the peripheral portion is deformed to be in surface contact. . The opening is deformed until the contact portion 6a comes into surface contact. At this time, if the adjacent heat exchange element 2 'and the convex portion are in contact with each other, they can be fixed by phrasing.

The concavo-convex pattern has an appropriate shape such as a waveform pattern close to a sine wave as shown in FIG. 2 and a circular projection as shown in FIG. Can be considered. The direction of the wavy pattern is inclined at a predetermined angle θ with respect to the longitudinal direction as shown in FIG. 4, and such plates 4 are arranged in opposite directions so that the wavy patterns cross each other. . Therefore, in the upper and lower plates 4, the contact portions 5 are formed where the ridges of the wavy pattern intersect in a mesh pattern, thereby forming a bent flow path in the internal space R1. At both ends of the plate 4, truncated conical raised portions 6 are formed, and the contact portions 6 a have an inclination of about β = 1 to 8 ° with respect to flatness, and become flat when superimposed and applied force.

An opening 7 is formed in the contact portion 6a. As shown in FIG. 2D, one of the openings at both ends is
When the rising portions 8 are provided and fitted into the openings of the adjacent heat exchange elements 2 ′ when they are overlapped with each other, positioning in the case of overlapping is facilitated. Note that the raised portions and the openings are not circular but may be rectangular (see FIG. 5). Further, the peripheral contact portion 9 of the plate 4 is formed with an inclined surface so as to make line contact when the plates are superposed face to face, to be deformed by adding power, and to make surface contact. The inclination of 9 has an inclination of about α = 1 to 8 °, and when a force is applied by overlapping the contact portions 9 so as to make surface contact,
As shown in FIG. 2B, the uneven patterns are formed so as to contact each other. Such plates 4 have the same shape and are stacked in the opposite direction.

Further, in order to facilitate the positioning when the plates are placed face to face and overlapped with each other, irregularities or notches and projections for engagement may be provided at several places on the peripheral edge portion (see FIG. 5). The heat exchange element 2 is formed by laminating two plates 4 and fixing them by welding or brazing between the contact portion 5 and the peripheral portion 9 of the uneven pattern. In this example, the heat exchange structure 3 is formed by stacking the three heat exchange elements 2, and the contact portion 6 a of the raised portion 6 is formed.
It is assembled by welding or brazing. Thereby, between the heat exchange elements 2,
A flow path communicating with the space inside the shell is formed.

Further, as shown in FIG. 1, a closing plate 11 is fixed to the opening 7 of the heat exchange element 2 on one side adjacent thereto, and the opening 7 on the other side is closed by heat. Exchange element 2
A pipe 12 for supplying and discharging the first heat exchange fluid is connected to the internal space R1. Note that a plate without the opening 7 may be provided at the final portion without providing the closing plate 11. The shell 1 is provided with through-holes 13 for leading these pipes 12, and a pipe 14 for supplying / discharging the second fluid is formed in the shell internal space R2 on the walls on both sides in the longitudinal direction. In particular, if the frusto-conical raised portion 6 is at the same height as the wavy uneven portion, the contact portion 10 of the adjacent heat exchange element 2
By welding or brazing the contact portions 6a of the protrusions 6 and the contact portions 6a, they are fixedly assembled. Thereby, the structural strength is further increased, and a curved flow path communicating with the space inside the shell is formed between the heat exchange elements 2, thereby improving the heat exchange capacity.

In order to manufacture such a plate-type heat exchanger, the two plates 4 are welded to form the heat exchange element 2, which is further overlapped and welded to form the heat exchange structure 3. However, a simpler method is to stack the six plates 4 alternately with the brazing material interposed between the peripheral portion 9 and the contact portions 6a of the openings and the contact portions 5 and 10 of the wavy pattern. It is a method of heating by placing it inside. Thus, the heat exchange structure 3 can be easily manufactured in one step and in large quantities depending on the capacity of the furnace. Also, as shown in FIG. 2D, a rising 8 is formed in one opening of the plate 4 and fitted into the opening of the adjacent heat exchange element, and further, as shown in FIG. By providing notches 22 and protrusions 21 for engagement at several places, if one is placed on the other, the plate 4 is naturally positioned and stably supported. Is made easier.

In addition, not only the heat exchange structure 3 but also
Placing a wax between the contact parts 5 and 10 or the contact parts 9 and other necessary places, the plate 4, the shell 1, the pipe 12,
By assembling 14 and the closing plate 11 and heating and brazing in a furnace, the entire heat exchanger including the shell 1 can be made at once. In the plate heat exchanger thus formed, each supply / discharge pipe 1
The first and second fluids are supplied to 2 and 14 to cause heat exchange. If the fluid or the low-pressure refrigerant vapor side when a phase change is caused by heat exchange is supplied to the larger internal space R2 of the shell 1, the flow becomes smooth. The first fluid flows through the flow path in the heat exchange element 2 as shown by the arrow A in FIG. 1, and the second fluid flows between the heat exchange elements 2 or as shown by the arrow B in FIG. It flows through a flow path formed between the shell 2 and the shell 1.

The wavy pattern is formed on the plate 4 for partitioning the flow path as described above, and the flow path is inclined at a predetermined angle θ with respect to the main direction of the flow connecting the openings 7. It is a complicated thing that bends left and right,
Therefore, the flow near the surface of the plate 4 becomes turbulent and flows, and heat exchange with the plate 4 is efficiently performed.
In addition, since the irregularities provided on the plate 4 are corrugated patterns and are intersected at a predetermined angle in this manner, the intersections of the grid-like ridge lines become the contact portions 5 and 10 and are arranged uniformly on the plate 4 surface. Also, the strength of the heat exchange structure 3 is very preferable. Fig. 2
A wave-like and sinusoidal wave as shown in (a) is advantageous from the viewpoint of heat conductivity, strength, etc. However, depending on the viscosity and phase change characteristics of the heat exchange fluid to be used, a circular protrusion as shown in FIG. , Or another shape can be appropriately selected. The height of the circular projection in Fig. 3 is changed by unevenness.
The size of the spaces R1 and R2 can be changed.

Further, projections are further provided at appropriate intervals on the projections of the waveform pattern, and spaces between adjacent elements (spaces R) are formed.
2) can be secured between the projections and between the openings 6a. Applications of the present heat exchanger include a condenser, a regenerator, an absorber, and an evaporator of an absorption refrigerator. For example, in the case of a condenser, as shown as a schematic configuration diagram in FIG. 6, a cooling water 15 flows on the R1 side, a refrigerant vapor 16 from the regenerator is guided from the upper side to the R2 side, and is taken out as a refrigerant liquid 17 from the lower side. . In the case of a regenerator, as shown as a schematic configuration diagram in FIG. 7, a heat source fluid 17 (hot water or steam in a single-effect absorption refrigerator, or refrigerant vapor from a high-temperature side regenerator in a multiple effect type) is introduced into R1, The solution 18 is led to R2, and the generated refrigerant 16 is generated from above. When steam is used on the R1 side, it is desirable that the opening is formed in a rectangular shape having a full width as shown in FIG. 5 so that the condensed liquid can be easily discharged.

[0020]

As described above, according to the present invention,
Since a flow path bent by irregularities is formed inside and outside of a heat exchange element composed of one or two types of parts, a low cost and efficient heat exchange function is achieved by a small number of parts and a simple manufacturing process. A heat exchanger can be provided.
Further, by fixing the uneven contact portions, the strength can be further improved, and by forming the irregularities periodically, heat exchange is performed evenly, the heat exchange function is high, and there is no thermal deformation. A highly durable heat exchanger can be provided. In particular, by forming the unevenness into a wavy pattern, a complicated flow path that bends two-dimensionally is formed with a relatively simple configuration,
A heat exchanger having a low-cost and efficient heat exchange function can be provided. In addition, the peripheral portion of the plate is bent so that a brazing material is inserted between the adjacent plates, and a configuration is made so that contact surfaces parallel to each other are formed in a state where a cap for brazing is added, and the brazing is fixed by brazing. For example, in a relatively simple and low-cost work process, a strong and leak-free joining is performed,
The use of so-called in-furnace brazing greatly simplifies the work process and reduces costs.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an example of a plate heat exchanger of the present invention.

FIG. 2 is an explanatory view for forming a plate of the present invention;
(A) is before weight formation, (b) is after weight formation, (c) is an enlarged view showing an example of a peripheral portion and an opening, and (d) is an enlarged view of another example.

FIG. 3 is a longitudinal sectional view showing another heat exchange element used in the present invention.

FIG. 4 is a schematic diagram showing the direction of the plate when the plates are overlapped.

FIG. 5 is another plan view of the plate used in the present invention.

FIG. 6 is a schematic configuration diagram when the heat exchanger of the present invention is used for a condenser of an absorption refrigerator.

FIG. 7 is a schematic configuration diagram when the heat exchanger of the present invention is used for a regenerator of an absorption refrigerator.

FIG. 8 is a cross-sectional configuration diagram showing a main part of a conventional heat exchanger.

[Explanation of symbols]

1: shell, 2: heat exchange element, 3: heat exchange structure, 4:
Plates 5, 10: contact portion, 6: raised portion, 6a: contact portion of opening, 7: opening, 8: (opening) rising portion,
9: peripheral contact portion, R1: space inside the heat exchange element, R2: shell side space, 11: closing plate, 12, 14: piping, 13: through hole, 15: cooling water, 16: refrigerant vapor, 17: refrigerant liquid ,
18: dilute solution, 19: concentrated solution, 21: protrusion, 22: notch

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Akiyoshi Suzuki 11-1 Haneda Asahimachi, Ota-ku, Tokyo F-term in Ebara Corporation (reference) 3L103 AA01 AA11 AA37 BB33 CC18 CC30 DD15 DD55 DD57 DD58 DD69

Claims (5)

[Claims] 1. A heat exchange element comprising: a pair of plates having projections and depressions and provided with openings at both ends, which are superimposed on each other to form one heat exchange element; A space between the two plates forming the first fluid as a passage of the first fluid, and a space between the heat exchange elements as a passage of another fluid (a second fluid) in a heat exchange relationship with the first fluid;
A plate-type heat exchanger in which a plate serves as a heat transfer surface for both fluids, wherein the plate has a plate edge and an opening at one end.
Having a contact portion with another plate of about 10 mm, the contact portion having an inclination of 1 to 8 ° with respect to the contact surface,
When the plates are overlapped as a pair, only the peripheral portions come into contact with each other, and when a force is applied and pressed until the uneven portions of the two plates come into contact with each other, the peripheral contact portions are deformed and the entire peripheral edges are brought into contact. When the heat exchange element and the element are overlapped with their openings aligned, only the periphery of the opening comes into contact, and the force is applied until the uneven portions of the plate between the heat exchange elements come into contact with each other. The plate-type heat exchanger is characterized in that, when pressed and pressed, the contact portion at the periphery of the opening is deformed and the contact portion at the periphery of the entire opening is in surface contact. 2. The plate heat exchanger according to claim 1, wherein the plates are integrated by brazing all the plates together at a contact portion of a plate peripheral edge or an opening. 3. The plate heat exchanger according to claim 1, wherein the unevenness of the plate has an oblique shape in one direction. 4. The unevenness of the plate is spot-like unevenness having a circular cross section, and when a heat exchange element is formed,
3. The plate heat exchanger according to claim 1, wherein the height of the convex side is larger than the depth of the concave side. 5. The plate according to claim 1, wherein one of the openings at both ends of the plate is swung so as to enter the other opening when the plate is overlapped. The plate heat exchanger as described.