GB2065909A - Welding shield - Google Patents

Abstract

A shield suitable for use in welding comprises an opaque front portion 3 having a transparent window 17, which is used for viewing under normal lighting conditions. A light screen 37, which is deeply tinted and movable to a position behind the transparent window 17, serves to protect a workman's eyes against intense light produced during welding. The shield is held by a handle member 29 provided with a trigger member 41 by means of which the light screen 37 may be moved. <IMAGE>

Description

SPECIFICATION Shield The present invention relates to a shield, more particularly a shield suitable for use in welding which may be used to protect a workman's eyes against intense light generated during, for example, arc welding.

It is well known that welders or other metal workers need some form of protection to prevent the intense light of, for instance, a carbon arc welding system from damaging their eyes. Curved portable shields are known which the welder holds in front of his face; these shields are provided with a window of heavily tinted toughened glass or other suitable material set in an opaque surround which forms most of the area of the shield. The window is so darkly tinted, usually with a red colour, that under normal lighting conditions it is almost impossible to see through the window. The very bright light produced by carbon arc welding or oxy-acetylene cutting or welding, however, is easily seen through the heavily tinted window.

When a workman is examining his workpiece after welding, he will not normally be able to make out any detail if he looks through the tinted window of the shield. However, it is not advisable for the workman to look at the workpiece directly; it is still desirable for him to have some physical protection in front of his face so as to guard him, particularly his eyes, against any flying debris which may be caused, for example, by dislodgement upon sudden contraction of the workpiece during cooling. Thus, it is important to provide the workman with a shield which is transparent under normal lighting conditions or at least a shield having such a transparent window, so that he may safely view the workpiece after welding or cutting.

It has hitherto been common practice in some parts of the world to provide a welder with two shields, one (the welding shield) being for the most part opaque but having a small heavily tinted window and the other (the viewing shield) either being transparent under normal lighting conditions in its entirety or having such a transparent window. Thus, the workman holds the welding shield in front of him while he is performing that operation and then, on completion, he lays down the welding shield and takes up the viewing shield to inspect the workpiece.

This procedure clearly has some disadvantages.

The workman is inconvenienced by having to replace one shield by another and there will be a short time when the workman will have no protection in front of his face while he is changing the shields. Furthermore, there is the disadvantage that two shields have to be provided, whereas it may well be cheaper to provide one shield which performs the functions of both shields.

According to the present invention, there is provided a shield suitable for use during welding, the shield having a window portion which is substantially transparent under normal lighting conditions and a light screen portion movable with respect to the window portion, to a position in a line of sight through the window p0rti0n, which light screen portion is adapted to reduce the intensity of transmitted light. Preferably, the window portion comprises a sheet of material set in an opaque surround; the light screen portion is preferably formed of a deeply tinted glass or plastics material.

The light screen portion may be manually movable; this is preferably achieved by the light screen portion being operatively connected to a manually movable trigger means. Thus, the light screen portion is advantageously pivotally connected to an intermediate member which is pivotally connected to the trigger means, the trigger means being pivotally mounted with respect to the window portion of the shield.

Trigger means may be provided with spring means to keep the light screen portion in the line of sight through the window portion when manual pressure is not applied to the trigger means. The shield preferably is provided with handle means which makes the shield readily portable and the trigger means is preferably pivotally mounted on the handle means.

For a better understanding of the present invention, and to show how the same may be put into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 shows a rear elevational view of a shield in accordance with the present invention, the view being taken from the side of the user of the shield; Figure 2 shows a view, part in section and part in elevation taken along the line Il-Il of Figure 1; and Figure 3 shows a view, part in section and part in plan, taken along the line Ill-Ill of Figure 1.

Referring now to the drawings, there is illustrated a shield 1 suitable for use in welding.

The shield has a flat vertical front portion 3 which is intended to face a workpiece, two inclined opaque side portions 5 and 7 which extend back from the front portion generaliy towards a user of the shield and an opaque top portion 9 which connects the front portion 3 and the two side portions 5 and 7. These front, side and top portions 3, 5, 7 and 9 are formed integrally together. The two side portions 5 and 7 are each substantially planar and extend back from the substantially planar portion at respective angles of about 650 in such a way as to diverge in a direction from the front of the shield towards a user behind the shield. The corners 11 and 1 3 formed by the intersections of the front portion 3 and the side portions 5 and 7 are rounded.

Towards the bottom of the shield, each side portion 5 or 7 are each cut away from the back so that their edges are inclined towards the front portion 3 to minimize the hindrance to a workman using the shield. The front portion 3 is semi-circular in elevation at the top of the shield and the top portion 9 consequently forms an inclined strip bent in the form of a semi-circle which joins the two side portions, one edge of the strip being attached to the front portion of the shield at a rounded corner 1 5. The top portion 9 is upwardly inclined by about 650 to the front portion 3 of the shield.

In the front portion 3 of the shield, which is for the most part opaque, there is provided a transparent window portion 1 7. A rectangular hole 19 is formed in the front portion 3 just below the point at which the front portion is formed with a semi-circular outline. The longer sides of the rectangular hole 19 are horizontal and the hole is positioned such that it is in a comfortable position for a workman to look through the hole at a workpiece when the shield is in use. On the front surface of the front portion 3, that is on the outside of the front portion which is towards the workpiece, a wall 21 surrounds the rectangular hole 19. The wall 21 is formed by four wall members arranged in a rectangle around the hole, the cross section of each wall member being substantially L-shaped.The long leg 23 of the L is outstanding at right angles to the plane of the front portion 3 of the shield and the short leg 25 of the L points in from the periphery of the rectangular hole 1 9. Spanning the area enclosed by the short legs 25 of the wall members is a panei 27 of toughened glass or plastics material forming the window portion 17.

Affixed to the front portion 3 below the rectangular hole 1 9 on the inside of the shield that is to the side of the front portion 3 towards a workman using the shield - is a handle means comprising a substantially trapezium like handle member 29, the two parallel sides of which are vertically aligned. The plane of the trapezium is at right angles to the plane of the front portion 3. The shorter of the two parallel sides of the trapezium like handle member 29 is formed as a strip 31 and is secured to the front portion 3 of the shield. The two non-parallel sides, which are both shorter in length than either of the parallel sides, are formed as braced strips and extend divergently back from the front portion 3 of the shield. They are both joined, to a tubular member 33 which is on the longer of the two parallel sides of the trapezium.

This tubular member 33 has a contoured grip so that the handle member 29 may be comfortably held by a workman. Pivotally connected to an upper portion of the tubular member 33 is a trigger means 35 which, as will be explained later, is used for moving a deeply tinted light screen portion 37. The trigger means 35 comprises an inverted U shaped channel member which forms a trigger support 39 which supports a depending trigger member 41. One end of the trigger support 39 is pivotally attached to the upper portion of the tubular member 33, the pivotal axis extending through one arm of the inverted U shaped channel forming the trigger support 39, the tubular member 33 and the other arm of the channel.The trigger support 39 extends away from the pivotal connection with the tubular member 33 towards the front of the shield, crossing the back upper corner of the area enclosed by the trapezium like handle member 29. The trigger member 41 itself is formed as a depending protrusion within the trapezium area bounded by the handle member 29 and is integral with both sides of the U shaped channel member forming the trigger support 39.

The trigger member 41 comprises two depending side portions, each depending from and substantially at right angles to a respective arm of the U shaped channel 39 forming the trigger support 39, and a front face bridging the two depending side portions. The trigger member 41 is thus positioned so that it can readily be operated by the hand of the workman which is holding the shield by the handle member 29.

At the end of the trigger support 39 furthest from the pivotal connection with the tubular member 33, the two arms of the trigger supports 39 are pivotally connected to an elongate intermediate member 43.

The trigger support 39 and the intermediate member 43 thus together form a bell-crank lever.

The end of the intermediate member 43 furthest from the pivotal connection with the trigger support 39 is pivotally connected to a support 45 for the deeply tinted light screen portion 37, which is movable. The intermediate member 43 is thus situated close to the front portion 3 of the shield, but on the inside thereof and the arrangement is such that by application of rearward finger pressure on the trigger member 41, the trigger support 39 and the intermediate member 43 move such that the deeply tinted light screen portion 37 moves downwardly parallel to the front portion of the shield.

The light screen portion 37 is formed of a rectangle of deeply tinted glass or plastics material. There is a frame surrounding this rectangle which comprises a simple strip 47 bent around the edges of the rectangle such that the plane of the strip 47 is always at right angles to the plane of the rectangle.

If no finger pressure is applied to the trigger member 41, the light screen portion 37 will be in position behind the rectangular hole 1 9 in the front portion 3 of the shield and hence behind the transparent window portion 17. Thus the shield 1 may be used for protection when looking at intense light such as that produced by carbon arc welding. A helical spring (not shown) may conveniently be provided around a pivot pin of the pivotal connection between the trigger support 39 and the tubular member 33 in such a way as to bias the trigger support 39 away from the tubular member 33; the light screen portion 37 is kept in position behind the transparent window portion 19 in this way.

When welding has been completed and the workman wishes to inspect his workpiece, he has merely to pull back the trigger member 41 with the forefinger of the hand with which he is holding the shield 1 by means of the handle member 29; the trigger member 41 and the trigger support 39 will then pivot downwardly and backwardly about the pivot pin of the pivotal connection between the trigger support 39 and the tubular member 33.

Therefore, by means of the intermediate member 43, the light screen portion 37 will be pulled downwardly out of the workman's line of sight through the transparent window portion 1 7.

There may be a cover member 49 provided over the space which the light screen portion 37 occupies when it is in position behind the transparent window portion 17 for viewing intense light. This cover member 49, which also serves as a guide member for guiding the motion of the light screen portion 37 parallel to the front portion 3 of the shield, may be formed as a three sided shallow box which is mounted over the rectangular hole 1 9 in the front portion 3 of the shield on the side which is nearer a workman using the shield. The base of the box, which is in a vertical plane parallel to the transparent window portion 17 the light screen portion 37 and the front portion 3 of the shield, is transparent. The box is without a lower-most horizontal side so that the light screen portion 37 may be removed vertically downwards from the position where it is substantially enclosed by the cover member 49, that is, from the position at which it is behind the transparent window portion 17. The uppermost side of the cover member 49 may be hingedly attached to the inside of the front portion 3 of the shield just above the rectangular hole 1 9. Thus the cover member 49 may be at least partially removable to facilitate cleaning of the surfaces of the transparent window portion 1 7 and the light screen portion 37.

Claims (11)

1. A shield suitable for use during welding, the shield having a window portion which is substantially transparent under normal lighting conditions and a light screen portion movable, with respect to the window portion, to a position in a line of sight through the window portion, which light screen portion is adapted to reduce the intensity of transmitted light.

2. A shield according to Claim 1, wherein the window portion comprises a sheet of material set in an opaque surround.

3. A shield according to Claim 1 or 2, wherein the light screen portion is formed of a deeply tinted glass or plastics material.

4. A shield according to Claim 1, 2 or 3, wherein the light screen portion is manually movable.

5. A shield according to Claim 4, wherein the light screen portion is operatively connected to trigger means.

6. A shield according to Claim 5, wherein the light screen portion is pivotally connected to an intermediate member which is pivotally connected to the trigger means, which trigger means is pivotally mounted with respect to the window portion.

7. A shield according to Claim 5 or 6, wherein the trigger means is provided with spring means to keep the light screen portion in the line of sight through the window portion when manual pressure is not applied to the trigger means.

8. A shield according to any one of Claims 1 to 7, which shield is provided with handle means.

9. A shield according to Claim 8 when dependent on Claim 6 or 7, wherein the trigger means is pivotally mounted on the handle means.

10. A shield substantially as hereinbefore described with reference to, and a shown in, Figures 1 to 3 of the accompanying drawings.

11. Any novel feature or combination of features described herein.