[0001] The present patent application relates to a hood for installation above cooktops,
which is frontally provided with a virtual barrier capable of automatically switching
on the lamps of the hood and/or activating the fan, whenever the virtual barrier is
interrupted.
[0002] The hood according to the present invention has been designed as a specific solution
to the excessive energy consumption typical of this type of devices.
[0003] As it is known, the user normally puts a pan on the cooktop, switches on the lamps
located in the lower part of the hood to provide light directly onto the cooktop and
activates the fan at medium-high rotation speed.
[0004] Very often, the lamps and the fan remain switched on until cooking is completed,
even if the user approaches the cooktop on occasional basis to check the food.
[0005] The effects of this behaviour are extremely negative in terms of energy consumption.
The lamps of the hood remain on also when the user is not around and the fan keeps
rotating at medium-high speed also when pans are covered (as it normally happens when
they are left unattended). Covered pans produce small amounts of steam that could
be easily disposed of with the fan stopped, or at least with the fan at minimum rotation
speed.
[0006] In view of the above, the hood according to the present invention has been devised,
which is capable of automatically switching on the lamps and activating the fan at
high rotation speed only when necessary.
[0007] In particular, after carefully examining how cooktops are used, it has become clear
that the action of the lamps and the fan at maximum rotation speed is only necessary
when the user approaches the cooktop.
[0008] In fact, in this situation the lamps are necessary to check cooking and the fan must
operate at maximum speed when lifting the lid of the pan since a considerable quantity
of steam is generated and rapid disposal is therefore necessary. To this end, the
hood according to the present invention has been provided with an electronic device
capable of activating a virtual barrier that extends downwards from the front edge
of the hood, thus covering the entire space between the hood and the cooktop.
[0009] Obviously, the barrier must be activated when cooking starts, by means of a suitable
button located on the frame of the hood, next to the traditional controls used for
the manual activation of the lamps and the fan.
[0010] Every time the user approaches the cooktop and stretches his hands out, i.e. to place
a pan, remove it or lift a lid, the interference causes the interruption of the virtual
barrier.
[0011] Such an interruption is translated as a signal of the user's presence next to the
cooktop. The hood immediately and automatically responds by activating the fan and
switching on the lamps.
[0012] The hood is also provided with a timer that favours the automatic deactivation of
the fan and the automatic switching off of the lamps when the set time has elapsed
after the end of the interruption of the virtual barrier. The elapsing of time is
considered as a confirmation of the fact that the user has left and therefore it is
no longer necessary to keep the lamps and the fan in operation.
[0013] As regards the lamps, the switching on/off can occur gradually in order to reduce
the visual stress for the user's eyes.
[0014] It must be noted that, apart from reducing energy consumption, the hood according
to the present invention features several advantages when compared to the traditional
technology.
[0015] First, it increases the average life of the lamps, since they are switched on only
when necessary. It also produces less noise pollution, since the fan is operated at
maximum speed - and therefore with maximum noise level - only when necessary. Finally,
it prevents contacts between the user's hands, the lamps and the fan controls, thus
reducing stress or dirt.
[0016] It must be said that the virtual barrier of the hood according to the present invention
can also be programmed so as to provide the switching on of the lamps and the activation
of the fan on a separate basis.
[0017] The hood according to the present invention can also feature the virtual barrier
on the remaining sides of the hood (apart from the front edge).
[0018] As regards the practical realisation, the virtual barrier can be of different types,
according to the technology used: optical barrier (by means of optoelectronic sensors,
cameras, etc.) or, alternatively, a barrier obtained with infrared rays or ultrasounds.
[0019] For major clarity the description of the invention continues with reference to the
enclosed drawings, which are intended for purposes of illustration and not in a limiting
sense, whereby:
- Fig. 1 is an axonometric view of the hood according to the present invention;
- Fig. 2 is a block diagram that illustrates the operating principle of the virtual
barrier according to three operating modes: as a means for the simultaneous activation
of the lamps and the fan; as a means for the single activation of the lamps; and as
a means for the single activation (or the increase of the rotation speed) of the fan.
[0020] With reference to the aforesaid figure, the hood (1) is provided with a device (2)
capable of activating a virtual barrier (B) under the front edge (1a) of the hood
(1) towards the cooktop by means of the corresponding switch (2a).
[0021] In view of the above, the interruption of the virtual barrier (B) determines the
immediate automatic switching on of the lamps (3) of the hood (1) and/or the activation
of the fan (4).
[0022] As regards the operating principle of the virtual barrier (B), the description continues
with reference to the block diagram illustrated in Fig. 2.
[0023] To this end, it must be said that the hood according to the present invention is
provided with an electronic device actuated by the manual ON/OFF switch (2a), featuring
a management and control microprocessor (not shown in the enclosed figures) which
is interfaced with the activation controls of the lamps and the fan and with a timer
by means of the activation means of the virtual barrier.
[0024] Once the virtual barrier has been activated, the interruption of the barrier by the
user sends the microprocessor a signal for the activation of the lamps and/or the
fan, according to the selected operating mode.
[0025] Thanks to the timer action, the microprocessor automatically determines the deactivation
of the lamps and the fan when the set time has elapsed after the last interruption
of the virtual barrier.
1. Hood with virtual barrier, of the type with lamps (3) and fan (4) with one or more
rotation speeds, characterised in that it is provided with means capable of activating
a virtual barrier (B) in one or more edges of the hood (1), with timer, management
and control microprocessor and manual ON/OFF switch (2a); it being provided that the
interruption of the virtual barrier (B) causes the microprocessor to send the activation
signal to the lamps (3) and the fan (4), according to the selected operating mode;
it also being provided that the elapsing of the set time after the last interruption
of the virtual barrier (B) causes the microprocessor to send the deactivation signal
to the lamps (3) and the fan (4).
2. Hood with virtual barrier according to claim 1 characterised in that the generation
means of the virtual barrier (B) consist in optical devices, such as opto-electric
sensors or cameras.
3. Hood with virtual barrier according to claim 1 characterised in that the generation
means of the virtual barrier (B) consist in infrared devices.
4. Hood with virtual barrier according to claim 1 characterised in that the generation
means of the virtual barrier (B) consist in ultrasound devices.