Note: Descriptions are shown in the official language in which they were submitted.
l 15790,~
Tlle l~resent invention relates to a casing for a fan-
forced l~eater with a radial blower which is provided with air-
intake and air-discharge orifices and has an approximately box-
type design.
Fan-forced heaters for wllich this ]cind of casing can
be used are produced in large (~uantities and have a great variety
of desiyns. These casings must satisfy aesthetic as well as
functional requirements. Tlle relatively high demand for an
aesthetic shape is due to the fact that these Ean-forced heaters
are used primarily in housello]ds and frecluently remai,n mounted
even ~ en they are not in use. ~i-th re~ard to their function
they must be so designed that they can be easily produced and
repaired in order to ma}~e it possi~le to calculate their costs
arrowly. I~hen in use the heaters must be easy to handle and
safe to opera-te and it is important that at a given electric
power consumption a lleating efficiency as high as possible with
uniform and noiseless discllarge of air is attained.
The present inven-tion provides a casing for a fan-
forced heater whicll satisfies these fundamental requirements to
the greatest extent possible.
In accordance with the present invention such a casing
for a fan-forced heater of the kind mentioned at the outset
comprises a one-piece front wall-bottom section, a one-piece
rear wall-cover section and two side wall-base sections. A rim
strip along the external longitudinal edges of the rear wall-
cover section and of the front wall-bottom section, spaced from
the wall concerne~, is l~ent inwardly by 1~30 and has at least one
recess and at least one projecting lug on the e~ternal longitudi-
nal edges of botll the front wall--bottom section and the rear wall-
cover section, said lug engaging said recess. The side wall-base
sections can be mounted on the assembled ~ront wall-~ottom and
rcar wall-cover section.
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In the casing of the prescnt invention the total casing
comprises merely four sinyle compollents. This reduces the cost
of its production and this also has afavourable effect when
assem~ling -che casing since rear wall-cover section and front
wall-bottom section can be joined in a very short ~ime, whereupon
only tlle side wall-hase sections are mounted thereon. of course,
it is possible to correspondingl,y interchange the shape of the
front wall-bottom portion and of the rear wall-bottom portion.
Eecause of the integrated side wall-base sections no
additional nase l~ortions have to be screwed to the casing, so
that the expenditure for mounting is reduced while the casing is
particularly sturdy and handy. The surface on which the base
portion of the sicle wall-base section rests can be at a slight
angle with the bottom of the front wall-bottom section so that
the exhaust direction points slightly upwards.
Because the rearwall-cover section and the front wall-
bottom section form a right angle these sections of the casing
are particularly well accessible to mountiny the component parts,
as for example, the rotor and switch. The advantages obtained in
the original mounting have an equally positive effect when making
repairs since the casing can be readily opened and closed and is
easily accessible.
The side wall-base sections are preferably made of
plas-tics and the front wall-bottom and rear wall-cover sections
are preferably made of metal. Since the sections mentioned last
are made of r,letal, the casing obtained is particularly strong and
can be sub~ec-ted to thermal stress. However, since plastics can
be used for tlle side wall-base sections, WlliCIl are lleated either
slightly or not at all, not only can these parts by produced as
one piece in an cxtrusion die at a favourable cost but a particu-
larly elcgant and appealing shape is thus obtained.
It is particularly advantageous to provide at least one
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safety screw passiny through aliyned boreholes in the side wall-
base section and rear wall-cover section. An additional lug for
receiving the borehole can be disposed on the side wall-base
section. T~le safety screws reliably allow the casing, which is
sturdily assembled per se, from holding together even in case of
impact stresses.
It has been lound to be favourable that the bent-over
rim strip of the rear wall-cover section extends beyond the front
wall of the front wall-bottom section like a beading. Likewise
it is also favourable that on changing to the front wall, the
bottom forms a forwardly curved beading. In this manner sharp
edges are avoided, thus increasing the handiness and creating a
nice shape on the one hand and protecting the sheet metal pro-
trusions of the e~haust orifices by the projecting beadings on
the other.
An intake orifice is preferably provided in the cover
of the rear wall-cover section and in the bottom of the front
wall-bottom section. An exhaust orifice is preferably provided
in the front wall of the front wall-bottom section substantially
immediately adjacent a side wall. A curved sheet metal part
wllich is at right angles to both the cover and the bottom and
partially tangentially encompasses the rotor extends from one
side of the exhaust orifice to the other. This arrangement
results in a particularly compact and space-saving construction.
- A large passage area for the intake air is provided by the intake
orifices on both the top side and the bottom side. This has a
favourable effect on the rate of air flow and reduces the intake
noises to a minimum. The air flow is guided past the heater
coils to the exllaust orifice, said sheet meta] part serving
sirnultaneously as a thermal screen for the plastic side walls and
the operating elements.
Recesses for receiving the operating elements are advan-
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tageously provided in the region of the side wall spaced from the
intake orifices. In this region the operating elements are
separated from the not zone by the curved sheet metal part. The
space for the operating elements is formed, without any substan-
tial additional requirement, by the variable curvature of the
curved sheet metal part. This variable curvature is required for
reasons of a laminar air circulation.
In a particular embodiment of the present invention the
rotor is proviaed with blacies wllich are alternately bent out
upwards and downwards at right angles to the plane of rotation.
This permits the air to be drawn in uniformly through the upper
and lower intake orifices.
~inally it has been found that the curved sheet metal
(e.g. iron) part and the rotor are held on the bottom of the
rear wall-bottom section by common check screws. Because of
this the total number of the required screw connections to be
produced when assembling the casing can be kept extremely low
so that the assembling time is reduced as compareci with that of
other constructions and the expenditure for component parts
for the mounting support is also reduced. Moreover the external
appearance of the casing is not optically marred by a plurality
of different screws and the largely smooth surface thus resulting
can be cleaned more easily.
The present invention will be further illustrated by
way of the accompanying drawings in which:
Figure 1 is a perspective view of a casing according
to a preferred embodiment of the invention,
Figure 2 is a horizontal section througll the casing
and the inner component parts,
Figure 3 is a partial perspective view of the front
wall-bottom section and of the rear wall-cover section of the
casing, and
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Figure 4 is a horizontal sec-tion through a si~e wall-
base section of tile casing.
Referring to the drawi.ngs, -the casing cornprises four
in~ividual sections, namely the front wall-bottom section 1, the
rear wall--cover section 2 and the two side wall ~ottom sections
3 and 4.
The rear wall-cover section has a rounded transition
between the cover 5 and the rear wall 6. A rim strip 9 and 10
along the free longitudinal edges 7 and 8 is bent over inwardly
throuah 180. The bending radius is distinctly larger than the
thickness of the sheet metal so that each bent-over rim strip 9
and 10 is spaced parallel to the cover 5 and to the rear wall 6
respectively. In the case of the rim strip 9 of the rear wall 6
the curvature is shaped li~e a circular segment over an angular
range of 90 while the remaining 90 are attained by a largely
vertical deflection. ~paced-apart rectangular recesses 21 are
provided in the rim strips 9 and 10.
On changing from the front wall 11 to the bottom 12
the front wall-bottom section has a forwardly curved beading 13.
In the front wall 11 the exhaust orifice 15 comprising a plur-
aiity of slots 14 is offsetwith respect to the side wall-base
section 4. Si.milarly the intake orifice 16 is disposed in the
cover 5 and tihe intake orifice 17 in the bottom 12. The free
longitudinal edge 18 of the bottom 12 is curved sligh-tly upwards.
On the free longi.tudinal edge 18 of the bottom 12 and the free
longitudinal edge 19 of the front wall 11 there are disposed
sheet metal parts 20 approximately in extension of the corres-
ponding surface. The width of said sheet metal parts and their
mutual spacing corresponds to the recesses 21. By means of the
sheet metal parts 20 and the recesses 21 the front wall-bottom
section 1 can be found with the rear wall-cover section 2 without
any effort. The two parts 1 and 2 are made of sheet metal.
0 2
Tl~e side wall-base sections 3 and 4 comprise an
approximately rectangular portion 22 and a base lug 23, which
has approximately the shape of an acute triangle. The approxi-
mately rectangul,ar portion 22 has a handle trough 24. The
external edge of the rectangular portion 22 is graduated inwardly.
Tn the region of t;~e rear wall the rectangular portion 22 has a
~rojecting lug 25, whicih is provided with a borehole 26.
On mounting the side wa]l-base sections 3 and 4 to
the assembled sections 1 and 2 the graduation rests against the
]o sections 1 and 2 while the external edge 28 of the side wall-
base sections 3 and 4 engages over the sections 1 and 2. The
borehole 26 is aligned with a borellole 29 in the rear wall 6
so that the entire casing can be fixed with only two screws,
(not shown). Tne side wall-base sections 3 and 4 are each made
in one ~iece of plastics by injection molding.
The curved sheet metal part 30 and the blower motor
are secured together with the rotor 31 to tne bottom 12. The
curved sheet metal part extends from one side of the heating unit
32 to the otner. Said heating unit is in turn disposed directly
ahead of the exhaust orifice 15. The sheet metal part 30 shown
in Figure 2 has a rad'us of curvature which increases from the
right to the left, said sheet metal part extending tangentially
to the rotor over a specific length.
The rotor 31 has blades which are alternately bent
upwards and downwards. The operating and indicating elements 33
and the built-in electric component parts 34 which are not shown
in detail, are so lloused in the casing region, which is hollowed
by the curvature of the bent sheet metal part 30, that they are
protected against the heat.
