GB2443430A

GB2443430A - Retractable igniter

Info

Publication number: GB2443430A
Application number: GB0621673A
Authority: GB
Inventors: Emanoel De Oliveira Cerqueira; Edson Lino Dos Santos
Original assignee: Petroleo Brasileiro SA Petrobras
Current assignee: Petroleo Brasileiro SA Petrobras
Priority date: 2006-10-31
Filing date: 2006-10-31
Publication date: 2008-05-07
Anticipated expiration: 2026-10-31
Also published as: GB0621673D0; GB2443430B

Abstract

A retractable igniter having a safety mechanism to retract the source of ignition during an inactive period comprises an ignition chamber 16, an ignition electrode 15 supplied with an ignition voltage from an electrical voltage assembly 13, an external 14 pipe encasing an internal pipe 18 that in combination with the ignition chamber 16 and the electrode 15 is displaced by sliding within the external pipe 14 by an activation lever 12. The external 14 and internal 18 pipes may be axially centralised by screws 24 that provide a clearance between the pipes 14, 18. Activation lever 12 may be actuated manually or automatically. The retractable igniter may be single device for igniting a combustible source such as gas pilot pipe and may be used in furnaces using gas or liquid fuels, in spark plug igniters of internal combustion engines which use gas, liquid or both fuels. The retractable igniter avoids unnecessary contact with high temperatures, high humidity, incrustations and corrosion in the combustion environment to prolong the life of the igniter.

Description

RETRACTABLE IGNITER

The invention refers to an electric igniter having a safety mechanism to retract the source of ignition during an inactive period, avoiding unnecessary contact of said source with the environment.

The invention is useful to ensure the safety of ignition systems in industrial furnaces and to protect the integrity of the electrical components of the igniter, preserving it from incrustations and corrosion and thus providing a longer useful life.

Ignition systems are continually exposed to damaging environmental conditions during the time of operation, such as high temperatures, high humidity, incrustations and corrosion from different types of combustibles used, etc. These conditions are aggravated when the igniter works within industrial oil burning furnaces. Exposure of electrical components of the igniter to the environment inside such furnaces may cause damage, such as incrustations and corrosion, which in turn causes ignition delays and a shortening of the useful life of said components.

The igniter described in this invention provides safety in industrial furnaces and protects the integrity of the electrical components of the igniter.

Broadly, this invenon relates to a retractable igniter including a mechanism to protect the source of ignition.

The invention provides an electrical igniter, with a safety mechanism that allows the source of ignition to be retracted during the period of inactivity, avoiding unnecessary contact of said source of ignition with the environment inside the furnace.

This invention applies to industrial furnaces using gas or liquid combustibles, in spark plug igniters for motors and internal combustion automotive

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motors which uses gas or liquid combustible or both.

This invention provides means to isolate electrical components of the igniter, safeguarding them from critical factors such as: humidity, high temperatures, incrustations and corrosion, providing a prolongation of their useful life.

The invention will be further described, by way of non-limitative example only, with reference to the accompanying drawings, in which:-FIGURE 1 illustrates the outside view of the igniter of present invention in a retractable position and in the exposed position of the ignition source.

FIGURE 2 presents the igniter including the high voltage assembly.

FIGURE 3 illustrates the inner view of the igniter in a retractable position the in the exposed position.

FIGURE 4 shows the inner components of the igniter.

The invention will now be described by reference to the attached Figures.

The present invention relates to a retractable igniter which comprises: a) an ignition chamber (16); b) an ignition rod or electrode (15), wrapped in an electrical insulating block (20), an insulating empty space (21) and a bottom insulating terminal (22), and ended in an electric terminal (23); c) an electrical high voltage assembly (13) inside an insulating box (11) and connected to the electric terminal (23) via an electrical cable (17) d) an external pipe (14) encasing an internal pipe (18); and e) an activation lever (12).

The electrode (15) within the ignition chamber (16) is only exposed to the environment during the ignition of a combustible source.

During the time of inactivity of the igniter, the electrode (15) remains safeguarded within the ignition chamber (16).

The retractable igniter is a single device for igniting a combustible source, for example a gas pilot pipe, which gas pilot pipe does not pertain to the scope of this invention and may be any available in the art.

Preferably, the total aperture of the ignition chamber (16) is approximately mm, but it may be sized only enough for the electrode (15) to be exposed to the combustible source.

The retractable mechanism of the ignition chamber (16) can be either manual or automated. The internal pipe (18) is displaced inside the external pipe (14) by sliding. This displacement towards the ignition chamber (16) is preferably conducted by the activation lever (12), at the time of ignition.

After ignition of the combustible source, the ignition chamber (16) is retracted again, remaining closed far from the combustible source.

While the ignition chamber (16) is in the retracted position, the electrode (15) remains inside of the external pipe (14) and the insulating box (11), which protect it from humidity during the blow down, from high temperatures, and from the grime coming mainly from combustible oil. Preferably the igniter is powered at or 220 VCA and ignition voltage is of about 14KV, 40 mA rms.

The internal pipe (18) is inserted into the external pipe (14) and is displaced axially. The displacement is limited by the activation lever (12).

The two pipes (18, 14) are centralized axially by means of screws (24) in such a way as to provide a clearance of 1.6 mm axially along them and limiting the displacement towards the ignition chamber (16) by the activation lever (12).

The ignition chamber (16) contains an adjustable screw nut (19) made of stainless steel including the high voltage electric ignition tip of 20 Ky.

The activation lever (12), may be made of carbon steel; the isolating box (11) made of aluminum; the pilot light gas pipe (14) made of carbon steel; the electrode (15) made of steel, with the ignition tip made of nickel/chrome;

Claims

1. Retractable igniter, comprising: an ignition chamber, an electrode, an electrical high voltage assembly, an external pipe, an internal pipe and an activation lever.

2. Retractable igniter according to claim 1, wherein the activation lever is operated manually.

3. Retractable igniter according to claim 1, wherein the activation lever is operated automatically.

4. Retractable igniter according to any one of claims 1 to 3, wherein the external pipe, encases the internal pipe which is displaced together with the electrode.

5. Retractable igniter according to any one of claims 1 to 4, wherein the electrical high voltage assembly is of about 14 Ky, 40 mA rms and includes at least one electric cable linking the electrode and an insulating box.

6. Retractable igniter constructed and arranged substantially as hereinbefore described, or with reference to any of Figures 1 to 4 of the accompanying drawings.

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Amendments to the claims have been filed as follows 1. Retractable igniter, comprising: an ignition chamber, an electrode, an electrical high voltage assembly, an external pipe, an internal pipe and an activation lever for displacing the internal pipe and exposing the electrode within the ignition chamber to the environment only during the ignition of a combustible source.

2. Retractable igniter according to claim 1, wherein the electrode is wrapped in an electrical insulating block, an insulating empty space and a bottom insulating terminal, and ended in an electric terminal.

3. Retractable igniter according to claim I or claim 2, wherein the internal pipe encases the wrapped electrode and is together displaced axially at the time of igniting said combustible source.

4. Retractable igniter according to any one of claims I to 3, wherein the external pipe, encases the internal pipe which is displaced together with the electrode.

5. Retractable igniter according to any one of claims I to 4, wherein the ignition chamber ends the internal pipe and has an aperture for exposing the inside electrode to said combustible source. * . *.., *5

* 6. Retractable igniter according to any one of claims I to 5, wherein the electrical high voltage assembly is inside an insulating box and is connected to an electric terminal via an electrical cable.

7. Retractable igniter according to any one of claims I to 6, wherein the activation lever is operated manually.

8. Retractable igniter according to any one of claims I to 6, wherein the (0 activation lever is operated automatically.

9. Retractable igniter according to any one of claims I to 8, wherein the internal and external pipes are centralized axially by means of screws that provide a clearance along the pipes.

10. Retractable igniter according to any one of claims 1 to 9, wherein the ignition chamber contains an adjustable screw nut including a high voltage electric ignition tip of 20KV.

11. Retractable igniter according to any one of claims I to 10, wherein the electrical high voltage assembly is of about 14 KV, 40 mA rms and includes at least one electric cable linking the electrode and an insulating box.

12. Retractable igniter constructed and arranged substantially as hereinbefore described, or with reference to any of Figures 1 to 3 of the accompanying drawings. * ** * S * * *S S... * . S... * S

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