This application claims priority to Spanish Patent Application No. U200802313, filed Nov. 11, 2008.
The present invention relates to an electrical connection device for a gas control valve of a gas heating appliance that includes a pilot flame.
There are known control valves adapted to gas heating appliances that include a pilot flame, such as water heaters, dryers, etc. The control valves comprise an electromagnetic safety valve that is housed in a body of the control valve and which closes the passage of gas in the event of the pilot flame being extinguished, and a thermocouple heated by a flame that generates an electrical current for operating the electromagnetic safety valve, keeping it energised while the pilot flame heats the flame thermocouple.
Such a control valve typically comprises an electrical switch as an additional safety element that acts on the electromagnetic safety valve when the water temperature in the gas heating appliance exceeds a certain temperature, cutting off at that point the supply of power to the safety valve. As the electromagnetic safety valve is not energised, it closes the passage of gas towards a burner of the heating appliance, regardless of whether the pilot flame remains lit.
In the prior art the use of electrical switches of the bi-metallic type is known, these being switched off if a certain temperature is exceed.
In addition, during the last few years a control valve which comprises an electrical switch of the butterfly type has been used which presents, among other drawbacks, problems with regard to the stiffness of the connections as well as assembly problems. In these types of control valves the electromagnetic safety valve is fixed by being threaded into the interior of a body of the control valve, with a subsequent reduction of both manufacturing and assembly costs.
For the purposes of solving the problems of control valves with a butterfly-type electrical switch, U.S. Pat. No. 7,073,526 B2 discloses a gas control valve that comprises a valve or electromagnetic unit, a spacer, a retention member that is threaded onto the body of the control valve to hold the electromagnetic valve and the spacer in the interior of the body, and a connector designed to be coupled to the spacer from the exterior of the control valve once the electromagnetic valve, the spacer and the retention member have been assembled on the control valve.
Finally, U.S. Pat. No. 3,654,591 describes a gas control valve that comprises an electromagnetic valve, an electrical switch that comes into contact with the electromagnetic valve, a thermocouple, and a retention member that holds the electromagnetic valve and electrical switch in the interior of the body of the control valve. The electrical switch comprises a substantially cylindrical insulating body and electrical connection terminals for the electrical connection to the electromagnetic valve and the thermocouple, where flexible electrical cables are respectively fixed.
An object of the present invention is to provide an electrical connection device adapted to a gas control valve as disclosed herein and as recited in the appended claims.
In accordance with one embodiment, a gas control valve is provided that comprises a valve body, an electromagnetic valve that is housed in the interior of the valve body and an electrical connection device. The electromagnetic valve includes a sealing member configured to seat against the valve body to provide a gas tight seal. The electromagnetic valve adapted to be powered by a thermocouple via the electrical connection device.
In one embodiment the electrical connection device comprises an insulating member, a first electrical terminal that is connected to the electromagnetic valve, and a second electrical terminal that is connected to the thermocouple, the first electrical terminal and the second electrical terminal being fixed to a base of the insulating member. The insulating member of the connection device also includes a seating member that is configured to rest against the sealing member of the electromagnetic valve in a manner that causes the sealing member to be pressed tightly against the valve body. The base and the seating member of the insulating member are independent to each other and connected by means of a flexible joint member.
An advantage of the present invention is that it provides a compact and simple electrical connection device that is adapted to press against the sealing member of the electromagnetic valve in a manner that prevents unwanted gas to be leaked from the valve body, and also ensures, at all times, a good electrical connection between the electrical connection device and the electromagnetic valve and thermocouple. In addition, the joint member connecting the seating member and base of the insulating member acts to absorb the manufacturing and/or assembly tolerances that exist between the sealing interface of the valve body made by the sealing member and a connection terminal of the electromagnetic valve.
These and other advantages and characteristics of the invention will be made evident in the light of the drawings and the detailed description thereof.
Other advantages and features of the invention can be seen in the following description in which, with a non-limiting character, preferred embodiments of the invention are referred to in relation to the attached drawings. In the figures:
With reference to
The control valve 1 also comprises a retention member 3 that is fixed to the interior of the valve body 2 by a exterior thread 3a, once the electromagnetic valve 4 and the electrical connection device 5 have been inserted axially into the interior of the housing 20, thereby holding the electromagnetic valve 4 and the electrical connection device 5 in place. The retention member 3 also includes an inner thread 3b in which the terminals of the thermocouple may be fixed.
The construction of electromagnetic valves is known in the art. As such, the details of the electromagnetic valve 4 have not been included in the description herein.
The electrical connection device 5, shown in detail in
The insulating member 6 is preferably made of a plastic/elastomeric material and comprises a first electrical insulation member/seating member 12 that has a top surface/support surface 12a that preferably presses uniformly against the sealing member 8 of the electromagnetic valve 4, a bottom surface 12b, and an aperture 12c extending between the top surface 12a and bottom surface 12b. The insulating member 6 further comprises a second electrical insulation member/base 11 having a first face 11a and a second face 11b, the second electrical insulation member 11 being situated in the aperture 12c of the first electrical insulation member 12 so that first face 11a resides within the aperture 12c and the second face 11b resides outside the aperture 12 below the bottom surface 12b of the first electrical insulation member 12. The first and second electrical insulation members are connected by means of a flexible or otherwise deformable joint member 10 that permits the first and second electrical insulation members to be moved relative to one another. As shown in
Preferably, the connection device 5 uniformly presses against sealing member 8 so that the sealing member 8 closes hermetically against the valve body 2, particularly against the inner edge 21, thereby preventing, when the electromagnetic valve 4 is energised, the leaking of gas to the exterior of the valve body 2, and also ensuring, at all times, a good connection between the first electrical terminal 7 and the connection terminal 4b of the electromagnetic valve 4. Due to the manufacturing and/or assembly tolerances of the different pieces that comprise the control valve 1, the distance A shown in
In one implementation, the second electrical insulation member/base 11 and the first electrical insulation member/seating member 12 have a substantially circular shape and are disposed concentric to each other, and are radially connected to each other by means of the joint member 10. In the embodiment of
As shown in the embodiment of
Further, the second electrical terminal 9 comprises a second inner contact terminal 9a that rests on or is otherwise fixed onto the second face 11b of the second electrical insulation member/base 11 and comes into contact with the terminal of the thermocouple in retention member 3 (not shown). The second electrical terminal 9 includes a second intermediate segment 9b that passes through the rib 15, and a second outer terminal 9c that projects out radially in relation to the insulating member 6, with the second inner terminal 9a, the second intermediate segment 9b and the second outer terminal 9c being continuous to each other.
In alternative implementations, one or both of the intermediate segments 7b and 9b of the first and second electrical terminals 7 and 9, respectively, reside on an external surface of the flexible joint 10, rather than passing through it.
The first electrical terminal 7 and the second electrical terminal 9 are insulated from each other by means of the insulating member 6. The first outer terminal 7c forms an angle B, preferably of 45° in relation to the second outer terminal 9c. In addition, in one embodiment, both the first outer terminal 7c and the second outer terminal 9c have a flat geometry and are fast connection terminals.
Number | Date | Country | Kind |
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U200802313 | Nov 2008 | ES | national |