FLUE

Background of the invention

[0001] The present invention relates to an arrangement for adjusting the operation of a flue valve in a chimney according to the preamble of claim 1. In particular, the arrangement is used for controlling the operation of a flue arranged to surround a smoke duct.

[0002] It is known as such to adjust the operation of a flue surrounding a smoke duct with a mechanically adjustable shutter vent structure arranged at the end of the chimney that is on the side of the room.

[0003] However, such a solution to be controlled separately is problematic because its use is completely dependent on one's memory. So, the flue is not often utilized in the best possible way so that it would support the operation of the fireplace as well as possible.

Brief description of the invention

[0004] An object of the present invention is thus to eliminate drawbacks of the prior art and to provide an arrangement of a novel type with which the flows in a flue can be easily controlled.

[0005] This object is achieved in such a way that the arrangement has, in accordance with this invention, the characterizing features defined in the claims. More precisely, the arrangement according to this invention is primarily characterized by what is stated in the characterizing part of claim 1.

[0006] Preferred embodiments of the invention are disclosed in the dependent claims.

[0007] The basic idea of the invention is that an air flow in a particular flue is adjusted automatically at the same time as a damper in the chimney is moved from one position into another. Such an arrangement, which can be described as semiautomatic, can also be made simple and reliable with regard to its structure.

[0008] Significant advantages are achieved with the invention. Thus, in a way, adjustment of an air flow in a flue can be automated. Also, the solution is simple in regard of the structure, which increases its reliability.

[0009] Accurate control is achieved with the solution, which guarantees reliable operation of the duct system as well as of the fixtures connected to the duct system, such as fireplaces or sauna stoves. [0010] The present invention is applicable to a steel-structure chimney, in particular, irrespective of the cross-sectional shape of the chimmey. The solution is at its best in chimneys with a round cross-section but the operational idea according to the invention can be equally applied to a chimney with an angular cross-section.

[0011] Other advantages achieved with the invention will be presented in the following when particular embodiments of the invention are described in greater detail.

Brief description of the figures

[0012] In the following, a preferred embodiment of the invention will be described in more detail with reference to the attached drawings, in which

Figure 1 shows schematically the position of a flue and a valve controlling it in a chimney element;

Figure 2 shows schematically an arrangement for opening and closing a flue surrounding a smoke duct;

Figure 3 shows schematically an arrangement according to Figure 2 from direction A-A illustrated in Figure 1 ;

Figure 4 shows an arrangement according to Figure 2 when the flue is closed;

Figure 5 shows an arrangement according to Figure 2 when the flue is open;

Figure 6 shows a second arrangement for opening and closing a flue surrounding a smoke duct, whereby the arrangement is illustrated obliquely from down when the flue is open;

Figure 7 shows a partial sectional view of an arrangement according to Figure 5 when the flue is half-open;

Figure 8 shows an arrangement according to Figure 5 when the flue is closed; and

Figures 9 to 11 show yet some alternative arrangements for opening and closing a flue surrounding a smoke duct.

Detailed description of preferred embodiments

[0013] In the present figures, the arrangement for controlling the operation of a valve in a flue in a chimney is not shown in scale but the figures are schematic, representing the principled structure and operation of some preferred embodiments. Thus, the structural parts indicated by reference nu- merals in the attached figures correspond to the structural parts denoted by reference numerals in this description.

[0014] The present arrangement is suitable to be used in connection with a chimney formed of chimney elements 1 according to Figure 1 , for example. Figures 2 to 11 show different embodiments of a valve 2 arranged at the end of the chimney that is on the side of the fireplace, it being possible to adjust an air flow in a flue 4 surrounding a smoke duct 3 of the chimney with these embodiments. In these figures, it is possible to schematically distinguish the main parts connected to a chimney element, i.e. a smoke tube 5 surrounding the smoke duct 3 and a first heat insulator 6 covering the smoke tube. Outwards from the smoke duct, the heat insulator is followed by a flue 4 which preferably extends from the end of the chimney that is on the side of the fireplace all the way to the upper part above the roof. The flue is further surrounded by another layer of heat insulator 7 (Figure 1), usually with a larger cross- section, and finally by a material layer forming an external covering 8 of the chimney and primarily formed of sheet steel. Although here an embodiment is presented which utilizes different heat insulator layers for reducing thermal stress from a smoke duct, it is naturally equally feasible to utilize the present arrangement in a chimney element with only some or none of the insulator layers described.

[0015] To control an air flow in the flue 4 of the chimney, the chimney is provided with at least two plate means with openings, arranged in pairs, and a function closing and opening the air flow in the flue can be achieved by guiding the reciprocal movement of these plate means. In a first extreme position of the plate means, an air flow in the flue can be substantially prevented, whereas in a second extreme position thereof, the flue can be opened for an air flow to take place in it. This air flow control is thus contributed to by at least one closing means 9 controlling the operation of the flue and forming one of the plate means. Arranged in its first extreme position according to Figures 4 or 8, this closing means is arranged to close the flue. Arranged in its second extreme position according to Figures 5, 6, 9, 11 , the closing means is, in turn, arranged to open completely, allowing the greatest air flow in said flue 4. The movement of the closing means 9 between these extreme positions is arranged to control the adjusting movement of a damper 10 that adjusts the flow in the smoke duct 3. [0016] In the embodiments according to Figures 2 to 1 1 , a damper plate portion 1 1 of the damper comprises a mechanical control means 12, which may be formed of a protrusion according to Figures 2 to 5 and 9 or a groove according to Figures 6 to 8 or 10 to 11. Via the control means, the closing means 9 is subjected to a mechanical force that moves the closing means either into a state closing at least one flow opening 13 or into a state opening the flow opening.

[0017] In the embodiment according to Figures 2 to 5, the valve 2 comprises a closing means 9 which is at least partly perforated to provide flow openings 13; cf. e.g. Figure 2 and its detailed illustration 2. This closing means is arranged concentrically and slidingly in the valve against an external covering 15, which is also partly perforated 14 and which forms one of the plate means mentioned above. Perforations of the flow openings and the external covering of the closing means are arranged to coincide over as large an area as possible when the valve has been guided into its open position; cf. e.g. Figure 5 and its detailed illustration 5. On the other hand, the flow openings and the perforation of the opposite plate means are arranged to deviate from each other when the valve has been guided into the closed position such that no essential air flow can pass through the flow openings; cf. e.g. Figure 4 and its detailed illustration 3. Between its two extreme ends, the valve allows at least a partial air flow.

[0018] In its embodiment according to Figures 6 to 8, the valve 2 comprises a closing means 9 provided at least partially with flow openings 13 and arranged concentrically and turnably against a valve base plate 17, which is also provided at least partially with openings 16 and which forms, in this embodiment, one of the plate means mentioned above. The openings of the closing means and the base plate are arranged to coincide over as large an area as possible when the valve has been guided into its open position; cf. e.g. Figure 6. On the other hand, the openings of these opposite plate means are arranged to deviate from each other when the valve has been guided into the closed position such that no essential air flow can pass through the flow openings; cf. e.g. Figure 8. Between its two extreme ends, the valve allows at least a partial air flow; cf. e.g. Figure 7.

[0019] In the embodiment according to Figures 2 to 5, the valve 2 operates as follows. The protrusion in the damper plate portion 11 , forming the control means 12, penetrates the closing means 9 through a groove positioned therein and forming a receiving means 18. This structure can be seen for instance in Figure 2 and its detailed illustration 1. The protrusion is formed in the damper plate portion in such a way that, most commonly, it extends substantially from a front edge 19 of the damper plate portion, abutted on the room, towards or even to a rear edge 20 extending into the smoke duct. At least at the end of the front edge, the protrusion is not positioned in parallel with a centre line 21 of the damper plate portion but forms an angle or a curve in relation to it. When the damper plate portion is pushed in a conventional way into the smoke duct 3 or when it is pulled from the smoke duct, the protrusion of the damper plate portion, approaching the centre line or moving away from it, exerts a mechanical force effect on the groove of the closing means, turning thus the closing means relative to the external covering 15 of the valve. Sliding along the surface of the external covering, the flow openings 13 of the closing means either become positioned against the perforation 14 of the external covering in accordance with Figure 5 or move away from it in accordance with Figure 4.

[0020] In the embodiment according to Figures 6 to 8, the valve 2 operates as follows, for example. The damper plate portion 11 has preferably a groove penetrating the damper plate portion as the control means 12. This groove is provided with a guide pin connected substantially rigidly to the closing means 9 according to Figure 7 and forming the receiving means 18, this guide pin thus penetrating the groove in the damper plate portion. This structure can be seen in the detailed illustration 6 of Figure 7. The groove is formed in the damper plate portion in such a way that, most commonly, it extends substantially from the front edge 19 of the damper plate portion, abutted on the room, all the way to the rear edge 20 extending into the smoke duct. At least at the end of the front edge, the protrusion is not positioned in parallel with the centre line 21 of the damper plate portion but forms an angle or a curve in relation to it. When the damper plate portion is pushed in a conventional way into the smoke duct 3 or when it is pulled from the smoke duct, the groove of the damper plate portion, approaching the centre line or moving away from it, exerts a mechanical force effect on the guide pin of the closing means, turning the closing means relative to the base plate 17 of the valve. When being turned along the surface of the base plate, the flow openings 13 of the closing means either become positioned against the openings 16 of the base plate in accordance with Figure 6 or move away from them in accordance with Figure 8.

[0021] It is characteristic of the present solution that the damper 10 or a part of it is in mechanical contact with at least one of the plate means in the valve 2, providing thus a reciprocal shift of these plate means.

[0022] Naturally, it is feasible to control the turning closing means 9 of the base plate 17 according to Figures 6 to 8 with a protrusion which cooperates with the groove in a flange protruding from the closing plate. It is also feasible that a protrusion or a groove controls the damper plate portion 11 to assume a sideward movement, which, in turn, exerts a mechanical force effect on an edge 23 of a penetrating groove 22 of the closing means in the manner shown in Figure 9.

[0023] Correspondingly, the groove forming the control means 12 in the damper plate portion 11 may cooperate with the closing means 9 being turned along the external covering of the valve. In such a case, the closing means is provided with a guide pin 18 according to Figure 10 and its detailed illustration 7, which transmits the movements of the damper plate portion to the closing means.

[0024] A mechanical force effect can be transmitted to the closing means 9 also by forming the control means 12 by means of a push bar 24 controlling the movement of the damper plate portion 11. By arranging the shape of the push bar diverging, for instance fraction-line-like in accordance with Figure 11 , a movement in the direction of a longitudinal axis 25 of the push bar provides a sideward mechanical force effect, which can be converted with the above procedures and structures into a force controlling the operation of the closing plate. In Figure 11 , the push bar preferably influences the closing means positioned against the base plate of the valve 2, for example in the manner shown in Figures 6 to 8.

[0025] The air flow arranged to pass through the flue 4 efficiently prevents heating of the second heat insulator layer 7 and the external covering 8 abutting on it, which form the external casing of the chimney, by transferring heat energy tending to pass towards the external covering away from the internal structures of the chimney. In this way, the conventional situation is avoided where chimneys transfer the stresses generated by the accumulation of heat energy onwards to the surrounding structures, such as to the intermediate floor and roof penetrations. In these prior art solutions, heat passes in a horizontal direction in the insulator space and causes heating of the structures, which may continue for several hours after the heating, significantly increasing a fire hazard.

[0026] It will be obvious to a person skilled in the art that as the technology advances, the basic idea of the above solution may be implemented in many different ways. The solution presented and its embodiments are thus not restricted to the above examples but may vary within the claims.