Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to wood fired type
hot-water boilers. There has heretofore been utilized wood
fired hot-water boilers, as discussed in detail hereinafter
for supplying hot-water to a bathroom and a kitchen, etc.
~ ccording to the present invention, there is pro-
vided an improved heating method and boiler to that of the
prior art. Such improvements involve substantial energy
savings since more effective utilization of energy from the
fuel is obtained. Such stems from increasing the heat trans-
fer areas of the boiler also providing better fuel combustion
in the combustion chamber together with increasing the amount
of water stored in the associated water storage chamber in-
side the boiler body and further, providing the possibility
of using paper scraps and combustible trash etc. as fuels.
In the case of the known boilers, when fuel such as
firewood, paper scraps, wood and combustible trash are or
become poor, or when the heat energy from burning out of the
fuel is weak, and after burning out, the outdoor air flows
into the ventilation flue comprising the combustion chamber,
numerous fire tubes, smoke box and flue thereof. Thus, more
n~merous fire tubes must be utilized in order to increase the
transfer effect. Such however results in a further drawback
in that there is provided more coolin~ effect because the
number of fire tubes are increased. Furthermore, closing
the flue thereof to prevent the outdoor air flow causes in-
complete fuel combustion because the fuel combustion for
keeping warmth is impossible when the flue is closed, be-
fore the burning out of the fuel in order prevent the cooling.
It is therefore a prime object of the present in-
vention to provide a wood fired hot-water boiler which over-
comes t~e aforementioned disadvantages, including, to provide
an arrangement wherein heat consumption from a boiler is
t~
kept at a minimum and which enables combustion for keeping
warmth and the complete combustion of the fuel, including
utilizing combustible trash, such being a poor fuel, weak in
fire power, and maintaining combustion until the burning out
of the fuel, where low or little quantity of heat in fuels
after burning out in the combustion chamber is present, also
having large heat transfer areas and having large water
storage capacity.
In one aspect of the present invention there is
provided a wood fired type hot-water boiler comprising a
boiler body having a feed-water inlet and a hot-water out-
let, a water storage chamber and a combustion chamber mounted
~ respectively in the upper and lower portions inside the
i boiler body and a plurality of fire tubes connected respec-
tively with the combustion chamber at an upper portion thereof
and with a smoke box formed at the lower end of a flue which
. is allowed to protrude toward the outside penetrating both
the water storage chamber and the upper end of the boiler
body at an upper portion thereof, characterize~ in that the
hot-water boiler comprises a first damper in the flue for
controlling the amount of ventilation through the flue; an
. auxiliary flue having a smaller diameter than that of the
flue, protruding outwardly from the boiler body and inter-
connected to the combustion chamber, and a second damper in
the auxiliary flue.
The invention is illustrated by way of example in
the accompanying drawings wherein:
Figure 1 is a sectional elevational view of a wood
fired hot-water boiler in accordance with the prior art, prior
to modification in accordance with the present invention;
: Figure 2 is a sectional elevational view of a wood
fired hot-water boiler in accordance with the present inven-
tion;
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Figure 3 is a sectional elevational view of the
boiler shown in Figure 2 including further modification.
The invention will become more apparent following
reference to the drawings and the description hereinafter.
Referring now to the prior art wood fired hot- -
water boiler shown in Figure 1. ~umeral 1 represents a boiler
adapted to receive feed-water into a water storage chamber 5
formed inside the boiler body 2, the feed-water being received
through feed pipe 4 connected to a feed-water opening 3 formed
penetrating through side wall 2b of the cylinder-like, boiler
body 2. Furthermore, at one end of feed pipe 4 is a cistern
tank 6 having a float valve therein and boiler body 2 further
having a hot-water suppl~ing opening 7 for feeding hot-water
heated in the storage chamber 5 in the boiler body 2 to a
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bathroom and kitchen etc. A drain valve 8 and an expansion
tube for pressure control 9 etc. are also provided for the
boiler body 2 as is conventionally known, thus detailed ex-
planation of these features is omitted.
Furthermore, at the lower portion of the boiler
body 2, an ash receiving part 11 having an ash removing open- -
ing 10 is provided and at the upper end of said ash re~eiving
part 11, a flange 12 is formed whereby a grate is supported
thereon. Above grate 13 there is provided a combustion
chamber 15 defined by an upper wall 15a and side walls 15b
thus providing the lower portion of said storage chamber 5.
A fire door 16 is provided penetrating through the side wall
15b of combustion chamber 15 and the side wall 2b of the
boiler body 2, corresponding to the side wall 15b respect-
ively so that such fuels as wood, paper, scraps, combustible
trash etc. may be fed therethrough. Further, there is pro-
vided a plurality of passages 17 which are perforated through
the upper wall 15a, passages 17 being inserted into respect-
.
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ively one end of the numerous water sealed fire tubes 18.
At the other ends of the numerous fire tubes 18, a smoke box
1~ is formed in the lower portion of flue 20. Furthermore,
flue 20 is adapted to protrude outwardly, penetrating the
upper wall 2a of the boiler body 2. Therefore, the combustion
gas and the air etc. generated in the combustion chamber are
exhausted to the outdoors via the ventilation flue, compris-
ing combustion chambex 15, the numerous fire tubes 18, smoke
box 19 and flue 20 in that order.
In Figure 2 there is shown the outline of a wood -
fired hot-water boiler 51 in accordance with the present
invention. Detailed description has been omitted since as
will be realized, marking the same numbers as the correspond-
ing portions to the Figure 1, said Figure 2 has the common
features with Figure 1 except for the following points, noked
in Figure 2.
A first damper 52 secured so as to be able to open or
to close to an appropriate position of the flue 20 protruding
through the upper wall 2a of boiler body 2 against the oppo-
site side of the smoke box 19 of the flue 20.
An auxiliary flue 54 extends upperwards along the
side wall 2b of said boiler body 2 connected outside thereof
with said combustion chamber 15 penetrating the side wall 2b
of said boiler body 2 and the outside wall 15b of said com-
bustion chamber 15 respectively therethrough, and a second
damper 55 secured adjacent the upper end of said auxiliary
flue 54 so as to be able to close or to open easily, said
auxiliary flue 54 having a smaller diameter than that of
said flue 20.
Figure 2 thus discloses, by way of example, a wood
fired boiler according to the present invention. With the
features shown in Figure 2, it is possible that when the hot~
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water boiler 51 is stoked, the fuels containing the combusti-
ble trash etc. are commenced to burn in a state of opening
the first damper 52 and closing the second damper 55 or
opening the ventilation flue consisting of the combustion
chamber 15, plurality of fire tubes 18, smoke box 19 and flue
20 is utilized, then during the period from becoming poor in
fuels to burning out of it, said second damper 55 is held in
open position while the first damper is closed and the ventila-
tion flue consists of the combustion chamber 15, auxiliary
fire tubes (not shown) and a~Yiliary flue 54 is utilized, be-
~ ing allowed to close the ventilation flue including said plur-
; ality of fire tubes 18 and further when the combustion is
ended, said second damper 55 is adapt~d so as to be in a
closed state. - -
Therefore, according to the present invention the
amount of heat loss from the fire tubes and the flue can be
controlled to a minimum when the fuel becomes poor or the fire
power is weak during the period until the fuel is burnt out,
and after the burning out of the fuel. Furthermore, since the
combustion of the fuel for keeping warmth is the complete use
of the fuel, and the use of combustible trash as fuels are
possible, various beneficial effects are obtained including
energy saving and prevention of environmental contamination.
Furthermore, the present invention is not limited to
the example described above since the auxiliary flue 54 ~ay
be attached at various alternative locations on the way up
the flue 20 The main point is that the air from the combus-
tion chamber 15 can only be allowed to exhaust outwards through
the auxiliary flue. Furthermore, the construction of the
b~iler may be modified to remove the attached portion of
flange 12 with grate 13 and the curved area of the combustion
chamber shown in Figure 1 and Figure 2 to that illustrated in
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Figure 3 thereby making it possible to simpli~y the construc-
tion and reduce overheat damage of the boiler body.
