WO2024144505A1 - A combi boiler main heat exchanger and production method - Google Patents

Abstract

The present invention relates to a heat exchanger (1) for use in combi boilers for heat exchange, comprising at least one coiled portion (2) having an inner part with a hollow form to allow fluid to pass therethrough, at least one end portion (3), which is located at the end portion of the coiled portion (2) where the coil terminates and which is adapted to be mounted on the boiler body (A) or on another liquid transfer portion outside the boiler body, at least one elevation form (4), which is located as a protrusion on the end portion (3) and allows a gasket to be positioned on the end portion (3), elevation form (4), which is a monolithic one-piece with the end-portion (3), and to a production method.

Description

A COMBI BOILER MAIN HEAT EXCHANGER AND PRODUCTION METHOD

Field of the Invention

The present invention relates to a main heat exchanger for use in combi boilers, which provides cost and installation advantages, and a production method.

Background of the Invention

In appliances burning gaseous fuel such as combi boilers, there are heat exchangers which are used to transfer the heat of the burning gas to the liquid. The said heat exchangers basically consist of an outer body comprising a gas mixture inlet, a burner, and a discharge hole for the burnt gas to exit, and a coiled tube in which the liquid circulates. The end portions of the said coiled tubes are connected to other tubes or to the outer body of the combi boiler and gasket elements are used to create sealing in this connection. In the state of the art, different methods are used in the production of coiled tubes for positioning the gasket on the end portions of the coiled tube. It is possible to examine the prior art under 2 separate categories. The first one is the case where the sealing is provided externally, while the other method is to ensure that the gasket that will provide the sealing is fixed in place with an additional part and/or apparatus.

In the case where the sealing is provided externally in the state of the art, the gasket that will provide the sealing is ensured to be fixed in place with an additional part and/or apparatus. In solutions where the sealing is provided outside of the main heat exchanger, there are basically 2 problems that may arise. The first one is the problem of how to ensure sealing. The part needs to be soldered or welded externally to ensure sealing. This has the potential to pose a problem for the sustainability of production. Another problem encountered is that sealing problems occur due to problems in the welding made to ensure sealing.

In the method of fixing the gasket in place with an additional part and/or apparatus to ensure sealing in the state of the art, there will be an additional cost due to the need for an additional part. Moreover, the said part can have a complex shape with respect to the profile of the coil itself. The complex shape in itself causes both the production to be challenging and the cost to increase. The problem experienced in the form of the part is due to the fact that the producibility and sustainability of the part cannot be ensured at the desired level. The more complex the part, the more complex the mold required to produce the relevant part will be. In mass production, the complexity of a part affects the production tolerances of the part and has a negative effect on the sustainability of the part. In addition, when the mass production conditions are considered, there is a possibility that the part which will keep the gasket in place on the sealing surface may be missed. If the relevant part is missing, then the entire main heat exchanger will not comply with the standards and therefore, it will not be able to fulfill its function and will be left as scrap. In order to overcome this issue, it is possible to adopt solutions such as adding a QR code on the relevant part. However, the addition of the QR code negatively affects the cost of the part, and an additional scanning process is required to scan the said code.

The patent application EP3139106B 1 in the state of the art relates to a heat exchange cell, wherein there is a helically shaped heat exchanger numbered 13 and the helically shaped heat exchanger is mounted by inserting its end portions (13C and 13 D) into the lower plastic elements. In the said application, the end form portion of the pipe intended to be coiled is not processed and sealing is ensured with an additional part. Patent application W02016001852A1 in the state of the art relates to a heat exchanger comprising a spiral pipe structure and the connection of the end portions of this heat exchanger. In the said document, the surface on which the gasket that will provide the sealing is to be fitted is created by first cutting the spiral end form and welding a part to the cut surface of the cut piece.

Summary of the Invention

The objective of the present invention is to realize a main heat exchanger for use in combi boilers, which provides cost and installation advantages, and a production method.

The objective of the present invention is to realize a main heat exchanger, which enables that the end form of the heat exchanger with a coiled structure can be adapted so that a gasket can be fitted thereon in an easy and cost-effective manner, and a production method.

Detailed Description of the Invention

The main heat exchanger developed to fulfill the objectives of the present invention is illustrated in the accompanying figures, in which:

Figure 1 is the front perspective view of the heat exchanger of the present invention before the cutting process.

Figure 2 is the front perspective view of the heat exchanger of the present invention after the cutting process.

Figure 3 is the front perspective view of the heat exchanger of the present invention.

Figure 4 is the front view of the elevation form detail of the heat exchanger of the present invention. Figure 5 is the front perspective view of the heat exchanger of the present invention, when mounted on the combi boiler.

Figure 6 is the front perspective view of the heat exchanger of the present invention before and after expanding process with a mold.

Figure 7 is the front perspective view of the heat exchanger of the present invention before and after the process of forming the elevation form with the mold.

The parts in the figures are individually numbered and their equivalents are given below.

1. Heat exchanger

2. Coiled portion

3. End portion

4. Elevation form

A. Body

M. Mounting inlets

C. Gasket

A heat exchanger (1) for use in combi boilers for heat exchange comprises: at least one coiled portion (2) which has an inner part with a hollow form to allow fluid to pass therethrough, at least one end portion (3) which is located at the end portion of the coiled portion (2) where the coil ends and which is adapted to be mounted on the boiler body (A) or on another liquid transfer portion outside the boiler body, at least one elevation form (4) which is provided as a protrusion on the end portion (3) and allows a gasket (C) to be positioned on the end portion (3), elevation form (4) which is a monolithic one-piece with the end-portion (3). The heat exchanger (1) of the present invention is used for heat exchange between the fluid (gas, burnt gas, etc.) coming thereto in the combi boiler and the fluid passing through it, and comprises a coiled portion (2) for circulating the fluid and end portions (3) for mounting the coiled portion (2) to another portion for fluid transfer. The said end portion is used by being fixed to the circular connection inlets (M) on the top cover, front cover and/or burner covers in the combi boiler. There is an elevation form (4) on the said end portions (3) for sealingly mounting the end portions (3) to the boiler body (A) to which they will be mounted or to another pipe with a gasket (C). This elevation form (4) is located as a protrusion over the end portion (3) and prevents the movement of a gasket (C) from the end portion (3) towards the coiled portion (2). With the positioning of the gasket (C) in this portion, a sealing is formed in case of connection of the end portion (3) with the boiler body (A) to which the end portion (3) is connected or with another liquid carrier (pipe, etc.).

In an embodiment of the invention, the coiled portion (2) has a flat structure, and the end portion (3) has a circular structure. The said elevation form (4) is located on this circular end portion (3). The said elevation form has a monolithic structure with the circular end portion (3). It is preferably formed by a molding process on the circular end portion (3).

In an embodiment of the invention, the elevation form (4) is located on the end portion (3) in the shape of a circular ring. In this way, the process of abutting the gasket (C) with a circular structure against the elevation form (4) over all its surfaces is performed.

A production method of the heat exchanger for use in combi boilers for heat exchange comprises the following method steps: providing a tubular structure comprising a coiled structure with a flat structure and an end portion with a flat structure, transforming the flat shape of the end portion into a circular shape, forming a protrusion form on the end portion, which is transformed into a circular shape, over the outer surface of the end portion.

In the production method of the heat exchanger, the structure having a coiled portion and end portion, which have a flat structure, is provided and the flat end portion is transformed into a circular form by an expanding process. The said circular form is a feature required for mounting to the circular portions of the top cover, front cover and/or burner covers in the combi boiler. After the said end portion has a circular shape, a protrusion form is formed on its outer surface for fixing the gasket during mounting. With the formation of the said protrusion form, the protrusion form enables the gasket to be positioned on the end portion and to be fixed in such a way that it stops before advancing into the coiled structure.

In an embodiment of the invention, the process of extending the circular portion is performed after the step of “transforming the flat shape of the end portion into a circular shape”. The said extension process is carried out by the process of thinning the thick circular shape and extending its length.

In an embodiment of the invention, this process is performed simultaneously or sequentially for both end portions extending from the coiled structure.

In an embodiment of the invention, before the step of “transforming the flat shape of the end portion into a circular shape”, the end portions extending from both coiled structures are brought to the same length on a plane. For the process of bringing them to the same length, a plane is drawn between the two end portions and the longer portion is cut off. In this way, both ends become suitable for the process step of forming the elevation form.

In an embodiment of the invention, the process of transforming the flat shape of the end portion into a circular shape is performed by inserting into the flat end portion a mold part having a circular portion which has a cross-sectional area greater than the inner cross-sectional area of the end portion. In this way, the end portion takes the form of a mold part with a circular outer surface. In an embodiment of the invention, in the process of “forming a protrusion form on the end portion, which is transformed into a circular shape, over the outer surface of the end portion”, the protrusion form is formed on the outer surface of the end portion by a mold part with a protrusion portion on its outer surface inserting into the inner surface of the end portion which is transformed into a circular shape and applying force in this portion.

In an embodiment of the invention, in the production method of the heat exchanger, heat treatments can be applied in the shaping process performed with the mold.

Claims

1. A heat exchanger (1) for use in combi boilers for heat exchange, comprising: at least one coiled portion (2) which has an inner part with a hollow form to allow fluid to pass therethrough, at least one end portion (3) which is located at the end portion of the coiled portion (2) where the coil ends and which is adapted to be mounted on the boiler body (A) or on another liquid transfer portion outside the boiler body, characterized by: at least one elevation form (4) which is provided as a protrusion on the end portion (3) and allows a gasket to be positioned on the end portion (3), elevation form (4) which is a monolithic one-piece with the end-portion (3).

2. A heat exchanger ( 1 ) according to claim 1 , comprising a coiled portion (2) with a flat structure, an end portion (3) with a circular structure, and an elevation form (4) which is located on the end portion (3) with a circular structure.

3. A heat exchanger (1) according to claim 1 or 2, comprising the elevation form (4) which is formed on the end portion (3) by molding method.

4. A heat exchanger (1) according to claim 1 or 2 or 3, comprising the elevation form (4) in the shape of a circular ring.

5. A production method of the heat exchanger according to claim 1, for use in combi boilers for heat exchange, characterized by the following method steps: providing a tubular structure comprising a coiled structure with a flat structure and an end portion with a flat structure, transforming the flat shape of the end portion into a circular shape, forming a protrusion form on the end portion, which is transformed into a circular shape, over the outer surface of the end portion.

6. A production method of the heat exchanger for use in combi boilers for heat exchange, characterized by the following method steps: providing a tubular structure comprising a coiled structure with a flat structure and an end portion with a flat structure, transforming the flat shape of the end portion into a circular shape, forming a protrusion form on the end portion, which is transformed into a circular shape, over the outer surface of the end portion.

7. A production method of the heat exchanger according to claim 5 or 6, characterized by the method step of performing the process of extending the circular portion after the step of “transforming the flat shape of the end portion into a circular shape”.

8. A production method of the heat exchanger according to claim 5 or 6, characterized by the method step of cutting the end portions extending from both coiled structures such that they have the same length before the step of “transforming the flat shape of the end portion into a circular shape”.

9. A production method of the heat exchanger according to claim 5 or 6, characterized by the method step of transforming the flat shape of the end portion into a circular shape performed by inserting into the flat end portion a mold part having a circular portion which has a cross-sectional area greater than the inner cross-sectional area of the end portion.

10. A production method of the heat exchanger according to claim 5 or 6, characterized by the method step of “forming a protrusion form on the end portion, which is transformed into a circular shape, over the outer surface of the end portion”, which is performed by a mold part with a protrusion portion on its outer surface passing inserting into the inner surface of the end portion which is transformed into a circular shape and transmitting force in this portion, thereby forming an elevation form on the outer surface of the end portion.