Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D47/00—Making rigid structural elements or units, e.g. honeycomb structures
  • B21D47/005—Making gratings
• • E—FIXED CONSTRUCTIONS
  • E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
  • E01D—CONSTRUCTION OF BRIDGES, ELEVATED ROADWAYS OR VIADUCTS; ASSEMBLY OF BRIDGES
  • E01D19/00—Structural or constructional details of bridges
  • E01D19/12—Grating or flooring for bridges; Fastening railway sleepers or tracks to bridges
• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
  • E04C2/00—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels
  • E04C2/30—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure
  • E04C2/42—Gratings; Grid-like panels
  • E04C2/427—Expanded metal or other monolithic gratings
• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04F—FINISHING WORK ON BUILDINGS, e.g. STAIRS, FLOORS
  • E04F11/00—Stairways, ramps, or like structures; Balustrades; Handrails
  • E04F11/02—Stairways; Layouts thereof
  • E04F11/104—Treads
  • E04F11/16—Surfaces thereof; Protecting means for edges or corners thereof

Definitions

• This invention related to an anti-skid tread and, more particularly, to an anti-skid tread having non-continuous, self-cleaning lobes and a method of making same.
• the present invention is directed to overcoming one or more of the problems as set forth above.
• the present invention has all of the advantages of the prior art devices including an anti-skid tread, in addition, the invention has non-continuous gripping edges that are provided by lobes that stick up high enough to provide the grip desired and wherein the lobes are configured and spaced in a manner to provide self-cleaning characteristics without compacting and accumulating debris.
• the crests of the lobes have rounded abrading edges for gripping the sole of the footwear or the bottom of a container, or the like, to reduce or eliminate slipping across the surface of the tread.
• a novel punch and backup ring are provided for punching gripping members or rosettes into a metal sheet to produce the tread or grating.
• a novel method is disclosed for punching the sheet using the punch and backup ring to manufacture the improved tread or grating.
• the improved grating or tread is easier and cheaper to manufacture while still maintaining all of the desired features and advantages.
• FIG. 1 is a top plan view of a gripping member of one prior art device
• Fig. 2 is a cross-sectional view taken along line 2-2 of Fig. 1 with a punch and die shown in phantom;
• Fig. 3 is a perspective view of a portion of a piece of tread or grating showing the improved rosettes or gripping members of the present invention;
• Fig. 4 is an enlarged plan view of a rosette or gripping member of the improved design;
• Fig. 5 is an enlarged view of a punch and backup ring with the punch penetrating a sheet of metal to form an improved rosette
• Fig. 6 is an end view of the punch of Fig. 5.
• Figs. 1 and 2 show one popular prior art grating 10 with a gripping member 12 having a continuous gripping and cleaning edge 14 struck upward from the plane of the grating 10.
• Each gripping member 12 may be made by positioning a backup die 16, shown in phantom in Fig. 2, against the under surface 18 of the plate 20 whereupon a circular punch 22, shown in phantom in Fig. 2, strikes the plate 20 from above and distorts the plate 20 at the edge 24 of the die 16 to form a conical surface 26 extending angularly away from the plate 20.
• the punch 22 penetrates the plate 20 leaving the continuous edge 14 about a circular aperture 28 in the plate.
• the plate After a plurality of gripping members 12 are struck from the plane of the plate 20, the plate is turned over so that the edges 14 project upward for gripping the bottoms of footwear walking on the grating.
• the apertures 28 will provide clean-out openings into which dirt, mud, ice, and the like, can be scraped. It has been found that the conical surfaces 26 are not long enough and the continuous circular edges 14 can become ice coated and less effective than desired. The mud and ice compacts in the apertures 28 and, if it dries or freezes there, reduces the gripping and cleaning ability of the grating.
• an improved gripping member or rosette 30 is shown struck from a plate 32 to form a grating or tread 34.
• a plurality of gripping members or rosettes 30 project upward from the plate 32, either in an established pattern or in a random pattern.
• the pattern of rosettes 30 in the plate 32 forms no part of the invention.
• Each gripping member or rosette 30 includes, preferably, three or four lobes 36 extending upwardly from the plane of the plate 32.
• Each lobe 36 is tongueshaped or has a somewhat parabolic configuration with the lobe 36 connected to the plate 32 along a circular path at a base 38.
• Each lobe 36 ascends upward and inward to form a crest 40 which is spaced from each crest 40 of the remaining lobes 36 to provide a star-shaped opening or aperture 42 between the lobes 36.
• Aperture 42 is defined by a continuous wall 41 extending around the edges of the lobes 36 and between adjacent lobes 36.
• Aperture 42 includes extensions 43 between adjacent lobes 36 which extend from the crest 40 of one lobe to the base 38 thereof and to the crest 40 of an adjacent lobe 36. Portions of wall 41 defining extensions 43 between adjacent lobes 36 are preferably divergent as they extend from base 38 to their respective crests 40, as is best shown in Fig. 4.
• a punch 44 which has a base 45 adapted to be connected to a moving head of ram 47 of a punch press, or the like, not shown.
• the punch 44 has a pointed leader 46 and a star-shaped cutting shank 48.
• the cutting shank 48 may have three or four radially extending flutes 50, each flute having a shape in horizontal cross section conforming to the extensions 43 of the aperture 42 in the resulting rosette 30.
• Each flute 50 has a flat end 51, the edges 53 of which form the cutting edge for the punch.
• the punch press not shown, has a guide 52 in which is formed an aperture 54 for receiving and guiding the punch 44 therein.
• a die 56 having circular cutouts or apertures 58, is positioned in the punch press with the axis of each cutout 58 aligned with the axis of an aligned aperture 54 in the guide 52.
• the die 56 with the cutout or aperture 58 aligned with the punch 44 in the guide 52 forms a backup ring 60 for the punch 44.
• the sheet or plate of steel 32 is placed on the top surface 62 of the die 56 whereupon the guide 52 is lowered against the top of the plate 32.
• the punch press is actuated to drive the punch 44 through the plate 32 to form the gripping members or rosettes 30 as the material of the plate 32 is deformed and pierced by the punch 44.
• the inside diameter of the cutout 58 in the backup ring 60 is slightly larger than the outside diameter of the punch 44 such that the edges 53 of the flat end 51 of the flutes 50 starts cutting the plate 32 on the outer periphery of the punch corresponding. to the inner periphery of the die 56. This causes the metal of the plate to be split into individual extensions 43 of the lobes 36 as the flutes 50 of the punch 44 pushes more metal ahead of it, to stretch the metal of the plate as it moves through the plate.
• the walls of the punch 44 will work the walls 41 of the extensions 43 and lobes 36 to shape them along a vertical path or even to give the wall 41 a shape which is slightly inwardly tapered or beveled toward the underside of the plate 32 as shown in Figs. 3 and 4.
• a small welt or ledge 66 is left around the top edge of the lobes 36 of the rosette 30 when the punch 44 is withdrawn, which welt or ledge 66 forms an additional cleaning edge for the rosette 30.
• the mud and ice is spread out and dispersed so as to loosen it, thereby causing it to fall through the opening 42 in the grating under its own weight and from the force of the cleaning stroke of the footwear across the grating.
• the lobes 36 are taller, sharper and provide individual points of contact which improves the anti-skid and the self-cleaning characteristics of the grating 10.
• the edges of the lobes 36 are non-continuous in a plane thereby giving non-continuous gripping to footwear brought in contact therewith. Non-continuous gripping is considered somewhat preferred in recent United States Government safety specifications.
• the non-continuous gripping edges of the lobes 36. of the rosettes 30 are not likely to become iced over since pressure on the grating will cause the edges of the crests 40 of the lobes 36 to penetrate and crack the ice loose.

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Mechanical Engineering (AREA)
• Tires In General (AREA)
• Road Paving Structures (AREA)
• Bridges Or Land Bridges (AREA)
• Panels For Use In Building Construction (AREA)
• Floor Finish (AREA)
• Steps, Ramps, And Handrails (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=22215803

Family Applications (1)

Country Status (4)

Cited By (3)

Families Citing this family (6)

Citations (10)

Family Cites Families (4)

• 1979
  • 1979-06-18 WO PCT/US1979/000431 patent/WO1980002856A1/en unknown
  • 1979-06-18 JP JP54501834A patent/JPS6224562B2/ja not_active Expired
• 1980
  • 1980-03-31 CA CA000348838A patent/CA1134589A/en not_active Expired
  • 1980-05-19 EP EP19800301638 patent/EP0021591B1/en not_active Expired

Patent Citations (10)

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