GB2053761A - A device for controlling fumes from soldering irons - Google Patents

Abstract

A soldering iron has a tip 4 joined by a shank 3 to a handle and a tube 1 extending along the shank. The tube and shank present an opening in the vicinity of the tip, and means is provided for drawing air containing fumes formed during soldering through the opening into the tube. The latter may be of glass or metal, e.g. steel. The drawn- off fume-laden air may be passed through a filter. In operation, the soldering iron extracts the hazardous fumes generated at the tip of the soldering iron in a typical soldering operation. <IMAGE>

Description

SPECIFICATION A device for controlling fumes from soldering irons The present invention relates to soldering irons having attached thereto an extraction system for removing fumes generated in a soldering operation.

Fumes are emitted from the tip of a soldering iron when solder and flux are melted during a soldering operation. Flux used in soldering is usually a resinous material, such as colophony, and it often contains a halide-based activator compound. Solder generally contains a substantial amount of lead. The fumes thus produced during a soldering operation using a resin flux generally comprise a mixture of vaporised resin and various breakdown products of the resin, vaporised activator, lead vapour and vaporised compounds of lead formed by the reaction of lead with constituents of the flux. Furthermore, the solder may often contain small amounts of cadmium which, when present, may substantially increase the toxicity of the fumes.

In view of the general hazard to the health of workers in the electrical component manufacturing industry who may work with, or in the vicinity of, soldering irons, the removal of such soldering fumes is of great concern. Indeed it is quite possible that the requirements of the Health and Safety Executive with respect to lead fumes are presently being exceeded for such people. Known control measured, such as conventional fume extraction systems, are expensive to install and operate. Furthermore, they remove large quantities of air and generally cause discomfort to the work force since they inevitably cause draughts.

The object of the present invention is to provide a system for extracting the hazardous fumes emitted from the soldering iron tip which avoids the drawbacks of the known conventional systems.

Accordingly, the present invention provides a soldering iron having a tip joined by a shank to a handle, and a tube extending along the shank and having an opening in the vicinity of the tip, and means for drawing air containing fumes formed during soldering through the opening into the tube.

The material which forms the tube may be any material which will withstand close contact with the shank of a soldering iron at operating temperatures without melting or being deformed. Preferably, the tube is made of glass or a metal, such as steel.

The tube is preferably attached to the soldering iron such that an annular air space is formed between the inside surface of the tube and the surface of the shank. The distance between these two surfaces is preferably about 0.5 mm. Usually the shank incorporates the heating element of the soldering iron.

The tube is of a length such that the end nearest to the tip does not interfere with working the iron or observing the bit during soldering operations.

The tube is connected, preferably by a plastics tube, to a pump. The pump induces a flow of air across the tip of the soldering iron and into the tube.

The induced air flow thus carries fumes emitted from the tip of the soldering iron into the tube from where they are conducted to a suitable discharge point.

Preferably, before the fumes are discharged from the extraction system they are passed through a filter suitable for preventing the escape of the more hazardous materials present in the fumes.

Ideally, in a factory situation, all soldering irons are connected to a central system for disposing of the soldering fumes.

In the accompanying drawings: Figure 1 is a diagrammatic axial cross-section of a soldering iron of the present invention wherein the fumes are extracted from the tube via a side arm; and Figure 2 is a diagrammatic axial cross-section of a soldering iron of the present invention wherein the fumes are extracted via a tube in the handle.

In Figure 1 a steel tube (1) is attached to a plate (2) at the base of the shank (3) of a soldering iron. The tube (1) is situated about the shank (3) such that the clearance distance between the inside surface of the tube and the surface of the shank is 0.5 mm. The length of the tube (1 ) is such that the tip (4) of the soldering iron is not obstructed during soldering operations. The tube (1) has a side arm (5) which is connected to a pump by a plastics pipe.

In operation, the pump causes air containing fumes formed during soldering to be drawn into the tube (1).

Figure 2 shows a different embodiment of the present invention in which the tube (1 ) extends through a small bore tube (6) which passes through the handle (7) of the soldering iron. The small bore tube (6) extends into a narrow flexible pipe (8) of 2-3 mm bore which is conveniently affixed to the electric supply cable (9) of the soldering iron.

1. A soldering iron having a tip joined by a shank to a handle, and a tube extending along the shank and having an opening in the vicinity of the tip, and means for drawing air containing fumes formed during soldering through the opening into the tube.

2. A soldering iron as claimed in Claim 1, wherein the tube is made of glass or steel.

3. A soldering iron as claimed in either Claim 1 or Claim 2, wherein the tube is attached to the soldering iron such that an annular air space is formed between the inside surface of the tube and the surface of the shank.

4. A soldering iron as claimed in Claim 3, wherein the inside surface of the tube and the surface of the shank are 0.5 mm apart.

5. A soldering iron as claimed in any one of claims 1 to 4, wherein the air containing the fumes formed during soldering are drawn through the opening into the tube and through a filter system.

6. A soldering iron as hereinbefore described with reference to and as illustrated in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A device for controlling fumes from soldering irons The present invention relates to soldering irons having attached thereto an extraction system for removing fumes generated in a soldering operation. Fumes are emitted from the tip of a soldering iron when solder and flux are melted during a soldering operation. Flux used in soldering is usually a resinous material, such as colophony, and it often contains a halide-based activator compound. Solder generally contains a substantial amount of lead. The fumes thus produced during a soldering operation using a resin flux generally comprise a mixture of vaporised resin and various breakdown products of the resin, vaporised activator, lead vapour and vaporised compounds of lead formed by the reaction of lead with constituents of the flux. Furthermore, the solder may often contain small amounts of cadmium which, when present, may substantially increase the toxicity of the fumes. In view of the general hazard to the health of workers in the electrical component manufacturing industry who may work with, or in the vicinity of, soldering irons, the removal of such soldering fumes is of great concern. Indeed it is quite possible that the requirements of the Health and Safety Executive with respect to lead fumes are presently being exceeded for such people. Known control measured, such as conventional fume extraction systems, are expensive to install and operate. Furthermore, they remove large quantities of air and generally cause discomfort to the work force since they inevitably cause draughts. The object of the present invention is to provide a system for extracting the hazardous fumes emitted from the soldering iron tip which avoids the drawbacks of the known conventional systems. Accordingly, the present invention provides a soldering iron having a tip joined by a shank to a handle, and a tube extending along the shank and having an opening in the vicinity of the tip, and means for drawing air containing fumes formed during soldering through the opening into the tube. The material which forms the tube may be any material which will withstand close contact with the shank of a soldering iron at operating temperatures without melting or being deformed. Preferably, the tube is made of glass or a metal, such as steel. The tube is preferably attached to the soldering iron such that an annular air space is formed between the inside surface of the tube and the surface of the shank. The distance between these two surfaces is preferably about 0.5 mm. Usually the shank incorporates the heating element of the soldering iron. The tube is of a length such that the end nearest to the tip does not interfere with working the iron or observing the bit during soldering operations. The tube is connected, preferably by a plastics tube, to a pump. The pump induces a flow of air across the tip of the soldering iron and into the tube. The induced air flow thus carries fumes emitted from the tip of the soldering iron into the tube from where they are conducted to a suitable discharge point. Preferably, before the fumes are discharged from the extraction system they are passed through a filter suitable for preventing the escape of the more hazardous materials present in the fumes. Ideally, in a factory situation, all soldering irons are connected to a central system for disposing of the soldering fumes. In the accompanying drawings: Figure 1 is a diagrammatic axial cross-section of a soldering iron of the present invention wherein the fumes are extracted from the tube via a side arm; and Figure 2 is a diagrammatic axial cross-section of a soldering iron of the present invention wherein the fumes are extracted via a tube in the handle. In Figure 1 a steel tube (1) is attached to a plate (2) at the base of the shank (3) of a soldering iron. The tube (1) is situated about the shank (3) such that the clearance distance between the inside surface of the tube and the surface of the shank is 0.5 mm. The length of the tube (1 ) is such that the tip (4) of the soldering iron is not obstructed during soldering operations. The tube (1) has a side arm (5) which is connected to a pump by a plastics pipe. In operation, the pump causes air containing fumes formed during soldering to be drawn into the tube (1). Figure 2 shows a different embodiment of the present invention in which the tube (1 ) extends through a small bore tube (6) which passes through the handle (7) of the soldering iron. The small bore tube (6) extends into a narrow flexible pipe (8) of 2-3 mm bore which is conveniently affixed to the electric supply cable (9) of the soldering iron. CLAIMS

1. A soldering iron having a tip joined by a shank to a handle, and a tube extending along the shank and having an opening in the vicinity of the tip, and means for drawing air containing fumes formed during soldering through the opening into the tube.

2. A soldering iron as claimed in Claim 1, wherein the tube is made of glass or steel.

3. A soldering iron as claimed in either Claim 1 or Claim 2, wherein the tube is attached to the soldering iron such that an annular air space is formed between the inside surface of the tube and the surface of the shank.

4. A soldering iron as claimed in Claim 3, wherein the inside surface of the tube and the surface of the shank are 0.5 mm apart.

5. A soldering iron as claimed in any one of claims 1 to 4, wherein the air containing the fumes formed during soldering are drawn through the opening into the tube and through a filter system.

6. A soldering iron as hereinbefore described with reference to and as illustrated in the accompanying drawings.