TECHNICAL FIELD
[0001] The present invention relates to a connector for a coaxial thermocouple, also known
as a tubular thermocouple, designed for its connection to an electromagnetic gas valve.
PRIOR ART
[0002] Coaxial or tubular thermocouples comprising a phase conductor and an earth conductor
axially disposed, with the earth conductor surrounding the phase conductor are known.
These types of thermocouples are more robust and offer a better connection and heat
evacuation than two-wire thermocouples, which comprise a phase conductor and an earth
conductor that are separate from each other. Because of this, coaxial or tubular thermocouples
are more suitable for domestic applications such as hob burners, ovens, etc.
[0003] Said coaxial thermocouple is generally connected to an electromagnetic safety valve
by means of a threaded part, as disclosed in
DE29609887U1, which is fixed to the end of the conductors of the thermocouple with the result
that the earth conductor is connected to the threaded part, thereby maintaining electrical
continuity. The phase conductor is insulatelly housed inside said threaded part, said
phase conductor coming into contact with the terminal of the electromagnetic valve
when the threaded part is attached to the electromagnetic valve
[0004] As well as making the product significantly more expensive, this threaded assembly
solution clearly slows down the assembly process and even hampers it on occasions
due to the difficulty of accessing the connection area.
[0005] ES1023977U describes a fast coupling for a coaxial or tubular thermocouple that comprises an
electrically conductive bushing that is fitted on to the free end of the tube and
has at least one radial projection that cooperates with a mouth disposed in the body
of the valve, thereby creating a bayonet-type connection between both.
BRIEF DISCLOSURE OF THE INVENTION
[0006] It is an object of this invention to provide a connector for a coaxial thermocouple
adapted for its connection to an electromagnetic gas valve as defined in the claims.
[0007] The coaxial thermocouple comprises a phase conductor and an earth conductor surrounding
the phase conductor. The connector of the coaxial terminal also comprises a phase
terminal that is fixed to one end of the phase conductor, the phase terminal being
a female terminal, an earth terminal fixed at one end to the earth conductor surrounding
the phase terminal, and an insulating member inside which is fixed the phase terminal,
the insulating member being housed at least partially inside the earth terminal.
[0008] As a result, a robust quick-fit connector for a coaxial or tubular thermocouple is
thus obtained, being designed for its connection to electromagnetic valves when they
include a male connector without needing intermediate members. This removes the need
to use threaded members that make the end product significantly more expensive, thereby
making the assembly of said connector to the corresponding electromagnetic valve easier
thanks both to the simplicity of said quick-fit connector and to the speed of its
assembly/connection. This type of quick-fit connector may even be connected in areas
of reduced size that are difficult for the user to access, thereby improving productivity
in its assembly.
[0009] These and other advantages and characteristics of the invention will be made evident
in the light of the drawings and the detailed description thereof.
DESCRIPTION OF THE DRAWINGS
[0010]
Figure 1 is a longitudinal section of a coaxial connector for a coaxial flame detection
thermocouple according to the invention.
Figure 2 is a lateral view of the coaxial connector shown in Figure 1.
DETAILED DISCLOSURE OF THE INVENTION
[0011] Figure 1 shows a coaxial connector 1 of a coaxial flame detection thermocouple fitted
to an electromagnetic gas valve, according to the invention, with the coaxial thermocouple
comprising a phase conductor 2 and an earth conductor 3 surrounding the phase conductor
2 externally.
[0012] The coaxial connector 1 comprises an electrically conductive phase terminal 4 that
is fixed to one end of the phase conductor 2, an electrically conductive earth terminal
5 that is fixed at one end to the earth conductor 3 surrounding the phase terminal
4, and an insulating member 6, preferably made of plastic, inside which is fixed the
phase terminal 4, the insulating member 6 being housed at least partially inside the
earth terminal 5.
[0013] The insulating body 6, which is substantially cylindrical and hollow, has a first
axial housing 9b through which is inserted the phase conductor 2 and a second axial
housing 9a, continuous and coaxial to the first axial housing 9b, that has a diameter
greater than the diameter of the first housing 9b. The phase terminal 4 also comprises
at least one elastic tongue member 7 that projects radially out of said phase terminal
4, the tongue member 7 expanding inside the second housing 9a when the phase terminal
4 is housed in the second housing 9a, thereby preventing any accidental disassembly
as the tongue member 7 comes up against a base surface 9c of the second housing 9a,
thereby fixing the phase terminal 4 to the insulating member 6.
[0014] In addition, the insulating body 6 comprises a first segment 6a that is inserted
tightly inside the earth terminal 5 and inside which the first axial housing 9b is
disposed, and a second segment 6b concentric and continuous to the first segment 6a,
inside which the second axial housing 9a is disposed, said second segment 6b including
equidistantly disposed axial slots 12, which make the second segment 6b more flexible,
the purpose being to make it easier to insert in the electromagnetic valve, which
is not shown in the figures.
[0015] Additionally, the earth terminal 5 has a substantially cylindrical shape with one
end 5b that is fitted concentrically to the outside of the earth cable 3 of the coaxial
thermocouple, said earth cable 3 being fixed to the end 5b by means of connection
means 11. In the embodiment of the invention described herein, the earth cable 3 is
fixed to the end 5b by means of welding 11, but in other embodiments not shown in
the figures, the earth cable 3 may be fixed to the end 5b by means of other fixing
means such as sticking, riveting or stapling by means of a clamp, clips etc. In addition,
the end 5b does not have to be cylindrical, as shown in Figures 1 and 2, and may have
a shape designed to collaborate with the corresponding fixing means for the correct
fixing of the end 5b and the earth cable 3, such as a tapered shape, for example.
[0016] As shown in Figure 2, the earth terminal 5 comprises axial grooves 8 that have a
first part 8a defined by a width d1 and a second part 8b defined by a width d2, the
second width d2 being greater than the first width d1.
[0017] The insulating member 6 also includes at least one external radial projection 10
on the first segment 6a, the projection 10 being defined by a width d3 greater than
at least the width d1 of the first part 8a, the projection 10 being housed in the
second part 8b of the groove 8, thereby fixing the insulating member 6 to the earth
terminal 5.
[0018] Finally, by means of the coaxial connector 1 the user may easily identify the type
of thermocouple to which said coaxial connector 1 is connected, thereby differentiating
it from any other type of connector. Identification is based on the differentiation
by colours of the insulating body 6.
1. Connector for a coaxial thermocouple adapted for its connection to an electromagnetic
gas valve, the coaxial thermocouple comprising a phase conductor (2) and an earth
conductor (3) surrounding the phase conductor (2), characterised in that it comprises a phase terminal (4) which is fixed to one end of the phase conductor
(2), the phase terminal (4) being a female terminal, an earth terminal (5) which is
fixed at one end to the earth conductor (3) surrounding the phase terminal (4), and
an insulating member (6) inside which the phase terminal (4) is fixed, the insulating
member (6) being housed at least partially inside the earth terminal (5).
2. Connector for a coaxial thermocouple according to the preceding claim, wherein the
insulating member (6) comprises a first axial housing (9b) through which a phase conductor
(2) is inserted and a second axial housing (9a), continuous and coaxial to the first
axial housing (9b), that has a diameter greater than the diameter of the first housing
(9b), and the phase terminal (4) comprises at least one tongue member (7) that projects
out of said phase terminal (4), the tongue member (7) expanding inside the second
housing (9a), thereby fixing the phase terminal (4) to the insulating member (6).
3. Connector for a coaxial thermocouple according to any of the preceding claims, wherein
the phase terminal (4) is housed completely inside the insulating member (6).
4. Connector for a coaxial thermocouple according to any of the preceding claims, wherein
the earth terminal (5) is fixed concentrically to the earth cable (3) by means of
connection means (11).
5. Connector for a coaxial thermocouple according to any of the preceding claims, wherein
the earth terminal (5) is substantially cylindrical and includes at least one axial
groove (8) that has a first part (8a) defined by a width (d1) and a second part (8b)
defined by a width (d2), the second width (d2) being greater than the first width
(d1) of the first part (8a), and the insulating member (6) is substantially cylindrical
and includes at least one radial projection (10) defined by a width (d3) greater than
at least the width (d1) of the first part (8a), the projection (10) being housed in
the second part (8b) of the groove (8), thereby fixing the insulating member (6) to
the earth terminal (5).