Fluid sprinkling – spraying – and diffusing – With means fusing solid spray material at discharge means – Wire or rod type supply
Reexamination Certificate
1998-05-08
2001-06-12
Morris, Lesley D. (Department: 3752)
Fluid sprinkling, spraying, and diffusing
With means fusing solid spray material at discharge means
Wire or rod type supply
C239S120000, C239S288000
Reexamination Certificate
active
06244519
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a torch for TIG welding, CO
2
gas shielded arc welding or the like used for metal welding or cutting.
2. Description of the Related Art
TIG welding, MIG welding, CO
2
gas shielded welding or the like widely used in the related industries usually utilize inert gas to shield arc as well as molten pool (welded zone) from the ambient atmosphere so that the molten metal may be protected from contact with harmful gas and thereby a welded joint of high quality may be obtained.
During operation of such welding, the enterprise is obliged to take an effective preventive measure, particularly for the operation of welding performed within the indoor workshop, in conformity with the regulations so that the operator may be protected from pneumoconiosis (welder's lung) caused by inhaling said metallic fume.
Specifically, the indoor workshop must be provided with general or at least local forced ventilation equipment in order to protect the operator from inevitably inhaling of said metallic fume and more strictly from exposure thereto.
However, it is sometimes difficult to install said forced ventilation equipment in order that the operator can easily move one welded zone to the next zone to be welded and convenience for operation can be ensured. In this case, the operator must wear a dustproof mask during operation of welding.
Regrettably, the dustproof mask imposes the wearer a breathing resistance. Additionally, light-shielding goggles (or spectacles) make it difficult to wear the dustproof mask or to fit the dustproof mask to the operator's face. In consequence, a dustproof effect may be unacceptably deteriorated or the operator's skin may suffer from eczema appearing on a region closely contacted by the dustproof mask. To avoid these problems, the operator often works without wearing of the dustproof mask.
There have already been several welding torches made on experimental basis provided on their outer peripheral walls with suction ports for welding fume as well as inert gas. However, none of these trial torches has been put to practical use for the reason that they are of heavy weight unacceptably for the operator and unable to achieve a desired ventilating effect.
Purpose of utilizing inert gas in the arc welding processes is to substitute the ambient atmosphere present in the vicinity of the molten pool with this inert gas and thereby to obtain a welded joint of high quality. However, so far as the indoor workshop (inclusive of the operation performed within a tank) is concerned, there may be an apprehension that not only a welder but also the other persons working in the proximity of this welder might inhale the metallic fume generated from the molten pool or at least might be exposed to such metallic fume. Additionally, there is a possibility that the inert gas utilized for shielding purpose also might affect the health of the welder if the inert gas is inhaled by the welder.
SUMMARY OF THE INVENTION
In view of the problems as have been described above, it is a principal object of the invention to provide an improved welding torch provided at its distal end with a hood adapted to collect harmful substances such as metallic fume. More specifically, said collection hood should effectively suck various harmful gases such as the welding fume to protect the welder and the other persons working in the vicinity of this welder from inhaling such harmful gases and/or being exposed thereto. It is also important for this collection hood to prevent said harmful gases from being scattered and diffused in a workshop. Finally, such preventive effect should be achieved without significantly disturbing the operation of welding.
The object set forth above is achieved, according to the invention, by features as will be described:
Welding torch comprising an inert gas jet nozzle surrounding a distal end of an electrode to gas-shield a welded zone and a suction port surrounding a distal end of said nozzle, said welding torch being characterized by that said inert gas jet nozzle is provided with a fume collecting hood. Said fume collecting hood surrounds the distal end of said inert gas jet nozzle so as to define said suction port between said nozzle and is detachably attached to said welding torch.
The fume collecting hood is attached to a gas shield cup defined by the distal end of the welding torch's nozzle. As has already been described, the fume collecting hood is provided with the suction port through which the welding fume generated from the molten pool together with the inert gas. A flexible pipe connected to an inlet side of a high static pressure exhaust blower or vacuum generator opens at the depths of the hood's skirt. Immediately after the inert gas shielded welding has been stabilized or as soon as the welding is started, air suction is started to collect the welding fume generated from the molten pool into the hood together with the inert gas without diffusing the inert gas in the ambient atmosphere.
A spatter and/or rough dust filtering mesh is disposed at an appropriate position between said opening of the pipe and said suction port of the hood. This screening mesh well avoids damage or clogging of said pipe due to welding fume and/or rough dust which otherwise might enter said flexible pipe.
A flange extending outward from the peripheral edge of the hood's opening and its particular configuration serve to improve a suction rate (or suction range) achieved in front of the hood and thereby to improve a collecting efficiency of the welding fume and the inert gas. In addition, the optimal suction vector is achieved by said flange and its configuration and thereby a desired shielding effect of the inert gas for the molten pool can be reliably maintained.
REFERENCES:
patent: 4388514 (1983-06-01), Coughlin
patent: 5129579 (1992-07-01), Conte
patent: 5756155 (1998-05-01), Tzeng et al.
patent: 5830334 (1998-11-01), Kobayashi
patent: 49-57525 (1947-08-01), None
patent: 50-129627 (1949-04-01), None
patent: 50-151821 (1949-06-01), None
patent: 51-7417 (1949-07-01), None
patent: 50-62837 (1975-05-01), None
patent: 5-280 (1993-01-01), None
patent: 673777 (1979-07-01), None
patent: 1563777 (1990-05-01), None
Hayakawa Masae
Ladas & Parry
Morris Lesley D.
LandOfFree
Welding torch having its nozzle member provided with fume... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Welding torch having its nozzle member provided with fume..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Welding torch having its nozzle member provided with fume... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2541156