[0001] The present invention relates to a safety device for domestic gas cooking appliances
comprising at least one cooking point which comprises a burner, a thermocouple arranged
to sense the presence of flame at the burner, and an electromagnetic safety valve
connected to said thermocouple and which, on opening, enables gas to flow to the burner
when the thermocouple senses the presence of flame at the burner.
[0002] It is not infrequently the case that through carelessness or inexperience a person
(for example a child) moves dangerously close to a burner to the extent of being struck
by the flame, with the serious consequences which can derive therefrom.
[0003] Also not infrequent is the case of fire danger where contact can occur between the
flame and flammable materials, with combustion facilitated by the flame of the gas
burner.
[0004] It is certainly true that action can be taken in these situations by closing the
valve member (taps) which regulate the gas flow to the burners, but it is also true
that in these situations panic is such that the presence of mind to positively act
in the stated manner can be lacking.
[0005] The main object of the present invention is to provide a safety device of easy access,
of immediate and direct intervention, structurally simple and economical, by which
the flame from the burner or burners is extinguished in cases of panic such as those
deriving from the aforegoing dangerous situations given by way of example.
[0006] This and further objects which will be apparent from the ensuing detailed description
are attained by a safety device in accordance with the teachings of the accompanying
claims.
[0007] The invention will be more apparent from the detailed description given hereinafter
by way of example with reference to the accompanying drawing, the single figure of
which schematically shows an embodiment of the invention.
[0008] With reference to the figure, which shows schematically an embodiment relative to
a gas cooking appliance with four burners, the invention being however also suitable
for a different number of burners, for each burner there is provided a thermocouple
(here indicated respectively by 1, 2, 3 and 4). When the flame has been lit, the thermocouple
concerned activates a relative safety solenoid valve (here indicated respectively
by 1a, 2a, 3a and 4a) to which it is electrically connected. The solenoid valves open
to enable the gas to flow to the burner (not shown).
[0009] The solenoid valves are positioned downstream of a respective valve 5 (only one is
shown in the figure for simplicity of representation) with which the user adjusts
the power of the flame at the burner by rotating a knob. These knobs are also axially
movable (see arrow A) against a spring (not shown), and when pressed and rotated they
close contacts 7 which connect a generic supply source 8 to the circuit in which the
thermocouple and safety valve are located, to cause the safety valve (1a in the example)
to open. In this manner the gas passes through the two valves 5 and 1a to reach the
burner where a conventional spark ignition device (not shown) ignites the gas with
consequent activation of the thermocouple 1, which then maintains the safety valve
1a open even after the user has released the knob 6.
[0010] The invention makes it possible for the user, if the danger situations described
in the introduction occur, to act rapidly to extinguish the lighted flame or flames
by interrupting the electrical connection between the thermocouples and the respective
safety valves. More specifically, with regard to the specific case shown in the figure,
each electrical connection comprises a normally closed contactor (1b, 2b, 3b, 4b),
all the contactors being joined together and hence operable by a single pusher 9 which
is dimensioned and colour-personalized in such a manner as to be immediately locatable
and operable.
[0011] Moreover, as shown, a normally open contactor 10 can also be provided which when
the pusher 9 is operated closes a circuit comprising an LED (or other light source)
or an audible alarm to hence activate it.
[0012] On abandoning the pusher 9, the contactors 1b, 2b, 3b, 4b and 10 can either return
by the action of a reaction spring into the position shown in the figure, or can remain
in the pusher-operated state and return to the position of the figure by operating
(pressing) the common pusher 9 a second time.
[0013] The opening of the contactors 1b, 2b, 3b, 4b breaks the connection between the thermocouple
and the safety valve, so that this latter closes to intercept the gas flow to the
burners, the flame of which is hence extinguished without being able to be reactivated
without repeating the normal burner ignition procedure.
[0014] Embodiments comprising one or more burners, each provided with safety valves and
thermocouples, evidently fall within the scope of the invention.
1. A safety device for domestic gas cooking appliances, comprising at least one burner,
a thermocouple (1, 2, 3, 4) for sensing the burner flame, and a safety solenoid valve
(1a, 2a, 3a, 4a) positioned within the gas flow to the burner and electrically connected
to the thermocouple, characterised in that within the electrical connection between the thermocouple and safety solenoid valve
there is located a normally closed contactor (1b, 2b, 3b, 4b) which can be manually
opened to interrupt said connection and hence extinguish the burner flame.
2. A safety device as claimed in claim 1, wherein, in the case of more than one burner,
all the normally closed contactors (1b, 2b, 3b, 4b) are operable together by means
of a single pusher (9).
3. A safety device as claimed in the preceding claims, wherein a display device (11)
is provided to display the open state of the normally closed solenoids, said display
device being controlled by a normally open contactor (10) connected to, and operable
together with, the normally closed contactors (1b, 2b, 3b, 4b).