State of the art Stovewood usage as. a fuel is highly diffused and has pushed to the construction of boilers which heat water both for heating and sanitary hot water, defined thermoboilers.

In actually commerced thermoboilers, in case they encrust by combustion smokes (creosote and other) the cleaning operations must be performed by hand. These operations are hard and must be performed when the boiler is off in order to avoid risks for workers. Such operations request specialised workforce and cleaning operations, after the garancy period is expired, are (if performed) at user's expences with a significant cost enhancing or (if the dust is being accumulated in the tubes) it provokes a fire danger.

Patent application GB-2185095 describes a thermoboiler in which the double-wall jacket is realized with a zigzag plate to constrain the smokes to flow over the plate folds and a deflector, containing as many fins as the plate folds are is installed, into a furnace. In this case the realization is complicated and therefore has elevated costs and the efficiency is not high because the surface of thermical exchange produced is not large.

The present invention aims to overcome the difficulties and disadvantages present in actually commerced technical solutions.

The main purpose of the present invention is to realise a heat exchanger with tube beam for thermoboiler using solid combustible in particles constituted by an external shell with a window having an opening handle, by an internal furnace fed by a conduct with said tubes which link a double-wall jacket realised in the superior part of thermoboiler characterized by fact that the tubes are made of copper and two scrape fins (end fin and intermediate fin) are installed on said tubes and that said scrape fins are linked by a grip, and can run over the tubes by half of length of said tubes.

One of the main advantages of present invention is to realise an exchanger for thermoboiler that can be easily cleaned from encrustations which appear on the copper tubes. The tar (creosote), which appears on the tubes is scraped away. This is realised by constraining the grip which commands the two fins and moves them forward and backward for half a length of the tubes. In such a way the tar and all the ensrustations are scraped away and the tubes remain always clean, enhancing the efficiency and reducing maintainance necessity.

Another characteristics is given by fact that between said furnace and said intermediate scrape fin a deflector is placed and said intermediate scrape fin and said deflector realise a smoke path up (first) and down (afterwards).

Another characteristics is given by fact that said deflector has an"L"-form ledge in the part of contact with intermediate scrape fin.

Another characteristics is given by fact that said intermediate scrape fin has in the part of contact with deflector a"Z"-form ledge.

Other characteristics and advantages of invention will be clear from the following description of the invention given as a not limiting example on figure 1.

Brief figure description.

Figure 1 represents a thermoboiler section with the heat exchanger, object of present invention; Detailed description of invention Making reference to figure 1, the thermoboiler 1 is constituted by an external shell 2, having a window 3 with an opening handle 4.

Inside the external shell 2 the furnace 7, fed by solid combustible in particles by means of conduct 5, is placed. Solid combustible in particles arriving from conduct 5 falls into the furnace 7, where in presence of air, substains the combustion. On the furnace 7 a heat exchanger with copper tube beam 6 is placed. Copper tubes 6 join to double-wall jacket 20 realised in the superior part of thermoboiler 1. Two scrape fins, end fin 8 and intermediate fin 9 joined to two ties 10 and 11 made solid by handle 12, are installed on tubes 6. Deflector 13 is mounted between furnace 7 and intermediate fin. Said deflector 13 has in the part of contact with scrape intermediate fin 9 an"L"-form ledge 16. Said scrape intermediate fin 9 has in the part of contact with deflector 13 a"Z"-form ledge. The combustion smokes are constrained to flow over the copper tubes 6 two times because deflector 13 and intermediate fin 9 constrain the combustion smokes first to go up and afterwards to go down flowing over the copper tubes 6 two times.

In such mode the thermal exchange between combustion smokes and copper tubes is enhanced with significant increasing of efficiency. Besides, copper tubes 6 can be easily cleaned of eventual creosote traces formed on them, by pulling forward and backward handle 12 and making fall the soot on furnace 7, provoking in this way the increasing of efficiency of thermoboiler 1 and making easier the cleaning of tube beam 6.

Obviously, the invention, is not limited to the representation delivered on the figures and can be improved by men skilled in the art without going out of the patent frame.

Present invention allows to obtain numerous advantages and overcome the difficulties that could not be superated with systems actually in commerce.