fig1 shows the component parts of a cartridge type safety goggle , comprising a goggle body 1 , cartridge or plate - holder 2 , a plate assembly comprising a cover plate 3 , gasket 4 , and filter plate 5 , and a retaining spring 6 . the cover plate 3 , gasket 4 , filter plate 5 and retaining spring 6 can be identical to those commonly used and known in the trade . the cover plate 3 is rectangular and can be made of glass . the gasket 4 is generally of the shape of a hollow rectangle , having outer dimensions correspond to the dimensions of the cover plate 3 and can be made from paper or other suitable gasket material . the gasket 4 serves to separate the cover plate 3 from the filter plate 5 in assembly so as to prevent contact of the two which might result in scratching . the gasket 4 also helps to keep the space between the cover plate 3 and filter plate 5 free of dirt and moisture . preferably the gasket 4 is opaque , so as to prevent light from entering the interior of the goggle through the edge of the clear cover plate 3 . the filter plate 5 is rectangular , having the same general size and shape as the cover plate 3 . the filter plate 5 can be made from glass or other suitable material known to the art . the filter plate 5 is darkened to prevent harmful light from reaching the eyes . the retaining spring 6 is in the shape of a bent hollow rectangle , having a size generally conforming to the size of the filter plate 5 , cover plate 3 and gasket 4 . the spring 6 can be made of resilient plastic or spring steel . although the details of the cartridge 2 will be more fully discussed below , it can be generally described as being rectangular having a front rectangular face 15 , a rear rectangular face 16 , a top edge 17 , a bottom edge 18 ( hidden ) and side edges 19 . the cartridge 2 has a rectangular viewing aperture 29 through the front and rear rectangular faces 15 , 16 . a channel 22 is formed on the interior portion of the top 17 , bottom 18 , and sides 19 of the cartridge 2 , by a front flange 23 and a rear flange 24 . the cartridge has slot 20 in one side edge 19 for inserting the cover plate 3 , gasket 4 , filter plate 5 and spring 6 . as can be seen also in fig3 the cover plate 3 , gasket 4 , filter plate 5 and spring 6 are held in the cartridge 2 with the cover plate 3 most forward , the gasket 4 immediately therebehind , the filter plate 5 behind the gasket 4 and the spring 6 most rearward . these items 3 , 4 , 5 , and 6 are inserted into the cartridge 2 through the slot 20 on the side 19 of the cartridge 2 . the cartridge 2 is fairly rigid and should be opaque enough to prevent an objectionable amount of light through it into the interior of the goggle . the surfaces of the cartridge 2 , can have a matt finish to reduce any possible reflection of light . the cartridge 2 has a plurality of tabs 21 , with spaces 25 between adjacent tabs 21 , on the top edge 17 and bottom edge 18 . in the preferred embodiment shown , the tabs 21 are in the form of a discontinuous ridge along the top and bottom edges 17 , 18 of the cartridge 2 . as can be seen also in fig3 and 4 the tabs 21 contact the interior surface of the goggle body 1 and also operate to position the cartridge 2 in a viewing aperture 10 in the body 1 . button - like protrusions 27 on the top 17 and bottom 18 of the cartridge 2 cooperate with holes 28 on the body 1 to hold the cartridge 2 in the body 1 . the goggle body 1 is made of a soft plastic so as to conform the contours of the face when worn , and is opaque so that light does not enter the interior portion of the goggle . the body 1 has a strap ( not numbered ) attached thereto to retain the goggle on a head . the body 1 has a rectangular viewing aperture 10 . a forward flange 13 surrounds the viewing aperture 10 on the front , and a rearward flange 14 surrounds the aperture 10 at the rear , forming a channel 12 around the aperture 10 to retain the cartridge 2 . the body 1 has a slot 9 in one side for inserting the cartridge 2 into the channel 12 . a plurality of holes 11 are formed through the goggle body 1 on the top and on the bottom clsoe to the front , along the lateral extension of the aperture 10 . referring briefly to fig2 one additional feature of the cartridge 2 is to be noted . fig2 is a partial perspective view of the top edge 17 of the cartridge 2 , which can be a mirror image of the bottom edge 18 . openings 26 are formed in the cartridge 2 adjacent to and rearwardly of the tabs 21 . these openings 26 establish air flow paths between the interior of the goggle and the area above or below the cartridge 2 behind the tabs 21 . fig3 is a front fragmentary view of the assembled goggle . as can be seen in fig3 the tabs 21 on the cartridge 2 are aligned with the holes 11 on the body 1 , so as to shield the interior of the goggle from any light entering the holes 11 . there are spaces 25 between successive adjacent tabs 21 which act as air flow passages from the holes 11 in the body 1 and the interior of the goggle . thus , air entering the holes 11 in the body 1 passes sideways , around the tab 21 and through the spaces 25 between the tabs 21 . the tabs 21 have a substantial length transverse to the holes 11 so as to help assure that light entering the holes 11 in the body does not have a straight - line or line - of - sight path to the interior of the goggle , and preferable not even to the space rearward of the tabs . thus , in operation , taking for example the top portion of the goggle , the openings 26 provide air flow from the interior of the goggle to the space above the cartridge behind the tabs 21 . the spaces 25 between tabs 21 provide air flow from the area above the cartridge 2 behind the tabs 21 to the area above the cartridge 2 forward of the tabs 21 . the holes 11 in the body 1 then provide air flow passage from the area above the cartridge 2 forward of the tabs 21 to the exterior of the goggle . a converse but similar operation would result at the bottom portion of the goggle . fig4 is a cross sectional view of the assembled goggle on the plane 4 - 4 in fig3 . as can be seen in fig4 the cartridge 2 is positioned in the channel 12 in the body 1 . the front and rear flanges 13 , 14 of the body 1 engage the front and rear of the cartridge 2 therearound , and the tabs 21 engage the interior of the body 1 at the top and bottom so as to form seals to the passage of light . the tabs 21 are positioned so as to be interposed at an intermediate position between the holes 11 in the body 1 and the openings 26 in the cartridge 2 . the cover plate 3 , gasket 4 , filter plate 5 and spring 6 are held between the rear flange 24 and front flange 23 on the cartridge 2 , by the action of the spring tension between the rear flange 24 of cartridge 2 and filter plate 5 . the holes 11 in the body 1 can be seen to be closely adjacent the tabs 21 , and in this embodiment are forward thereof . the openings 26 in the cartridge 2 can be seen to be generally in the plane of the spring 6 . these openings 26 are located closely rearwardly of the plane of the filter plate 5 so that air flow in the interior of the goggle passes from the openings 26 at the bottom , and is directed in a path close to the inside or rear surface of the filter plate 5 , to the openings 26 at the top so as to provide good ventilation to the surface of the filter plate 5 . it will be appreciated by those skilled in the art that modifications can be made to the preferred embodiment without departing from the invention . for example , the placement of the holes , tabs , openings and air passages can be modified either alone or in combination without departing from the invention . certain aspects of the invention also have application to other plate type safety goggles such as the &# 34 ; flip - front &# 34 ; types . other details , common to goggles in general can be changed without departing from the invention . therefore , it is intended that the invention only be limited by the following claims wherein
a cartridge type safety goggle for welding is disclosed having an improved ventilation system . a cover plate , gasket , filter plate and retaining spring are held in a cartridge , which is adapted to be inserted into a goggle body . a plurality of ventilating holes on the top and bottom of both the goggle body and the cartridge combine with a plurality of tabs on the cartridge to provide an air flow path which provides improved ventilation for the inside surface of the filter plate and yet prevent objectionable light from entering the interior of the goggle .