Field of the Invention
This invention relates generally to a means for highlighting the front edge surfaces of stair steps for safety purposes, and particularly to a new and improved clip-on plastic strip that can be readily attached to the front bar of a metal stair to make the front edge of the step highly visible from the front and from above. The strip is constructed in such a way as to be unaffected by foot traffic so that it will remain in place over an extended length of time.
Background of the Invention
Metal stairways commonly are used on offshore drilling rigs and platforms, as well as many ocean going vessels. If the front edge surfaces of the steps are not highlighted in some way so as to be clearly visible, persons using the stairs are apt to stumble and fall and sustain personal injury. For this reason, both U.S Coast Guard and OSHA (Occupational Safety and Health Administration) regulations require that the front edges of such stair steps be made plainly visible. To comply with these regulations in the past, the front edges of the metal stair steps have been painted or taped a bright color. However, with foot traffic and weathering, paint and the like peels and chips off to create a hazardous and highly undesirable situation.
The general object of the present invention is to provide a new and improved stair edge identifier that is long lasting, economical to manufacture and unaffected by foot traffic.
Another object of the present invention is to provide a new and improved stair edge identifier in the form of a elongated, plastic member that clips onto the front edge of a metal step in a manner such that it is readily visible from both the front and the top of the step, but is not engaged by the foot of a person who ascends or descends the steps.
Summary of the Invention
These and other objects are attained in accordance with the concepts of the present invention through the provision of a clip-on, colored identifier for the front bar of a metal stair step. The strip has a front portion with the general shape of a "U", and a rear portion in the form of a flange that is joined to the upper edge of the rear wall of the front portion and inclines rearwardly and downward thereof. The front portion of the strip member is formed so that the upper edges of the front and rear walls thereof are spaced apart, in a relaxed state, by a lesser distance than the width of the lower wall. To slide the front portion upward onto the front bar of the step, such upper edges must be spread apart somewhat, and the resilient nature of the member cause the front and rear walls to firmly grip the bar. The fact that the rear portion of the member is inclined makes it plainly visible from above, and causes it to shed water or any other liquids that might fall upon it.
Brief Description of the Drawings
The present invention has other objects, features and advantages which will become more clearly apparent in connection with the following detailed description, taken in conjunction with the appended drawings in which:
FIG. 1 is a fragmentary front view of a metal stairs showing identifier strips in accordance with the present invention secured to the front bars of the steps;
FIG. 2 is a view similar to FIG. 1 but showing the stair steps from above;
FIG. 3 is an isometric fragmentary view of an identifier strip member to illustrate the relaxed cross-section thereof; and
FIG. 4 is a side sectional view showing the identifier strip in position on the front bar of a metal stair step.
Detailed Description of a Preferred Embodiment
Referring initially to FIG. 1, a metal stairs indicated generally at 10 of the type typically found on marine structures such as drilling rigs, production platforms, and other water going vessels includes side members 11 having steps 13-15 extending therebetween. Each step resembles a grate having a plurality of rectangular, transversely arranged bars 16 that are joined by a plurality of rods 17 that extend front to rear, and which are welded to the bars 16 at all points of intersection. Each bar 16 can have serrations or teeth on its upper edge to provide improved traction with the shoe of a user. For a typical metal stair having a total width of three (3) feet, the length of each of the bars 16 is about 34 inches. Each bar, including the front bar, has a vertical height of about 3/4 of an inch, and a thickness of about 1/4 of an inch.
As shown in FIG. 1, an identifier strip 20 constructed in accordance with the present invention clips onto the front bar 16 of each step, so as to clearly identify the front upper edge thereof. As shown in FIG. 2, a rear flange (26) on each of the strips 20 also make it visible from above to a person who is descending the stairs.
With reference to FIG. 3, the strip member 20, which is made of a suitable resilient, brightly colored, plastic material, has a generally U-shaped front portion 21 that includes a front wall 22, a bottom wall 23 and a rear wall 24. These wall each have a thickness of about 0.003 inch. The front and bottom walls 22 and 23 preferably are formed at a right angle to one another, however the rear wall 24, in the relaxed state of the strip 20, inclines upward and inward toward the upper edge 25 of the front wall 22 so as to leave a gap at the top of about 1/8 of an inch, the acute angle between the bottom and rear walls being about 60.degree.. The front wall 22 has a height of about 3/4 of an inch, and the bottom wall 23 is about 5/16 of an inch wide. The inclined rear wall 24 can have a height that is slightly greater than the height of the front wall 22, as shown. The rear portion or flange 26 of the member 20 has its upper edge 27 joined to the upper edge of the rear wall 24 and inclines rearward and downward at an angle of about 45.degree. with respect to the plane of the rear wall 24. The rear portion of flange 26 also has a thickness of about 0.003 inch.
In use, a clip member 20 is attached to the front bar (16) of each metal stair step as shown in FIG. 4. The top edges of the front and rear walls 22 and 24 are spread slightly apart, and then the member is slid from below upward onto the front bar 16 until the bottom wall 23 is near, if not up against, the bottom surface of the bar. The resilient nature of the plastic material causes the walls 22 and 24 to resile toward each other and tightly grip the bar 16 to retain the strip member 20 firmly in place. The rear flange 26 of the strip member 20 inclines downward and rearward at the acute angle mentioned above so as to be plainly visible to a person descending the stairs. The inclined flange 26 also serves to run off water or other liquids that fall on the stairs from above.
The strip members 20 preferably are made of a plastic that has a bright color, such as yellow or red. Since the upper edges of the walls 22 and 24 are located below the tread surfaces of the steps, the members 20 are unaffected by foot traffic and cannot readily be knocked or pushed off. The strip members 20 will not wear or peel off like paint or tape, and thus provide an essentially permanent solution to the problem of stair step edge identification. The strips can be manufactured in long lengths and cut off to fit a particular application, and are quite inexpensive to make. Installation is rather simple, and does not require any tools whatsoever.
Since certain changes or modifications may be made in the disclosed embodiment without departing from the inventive concepts involved, it is the aim of the appended claims to cover all such modifications and changes falling within the true spirit and scope of the present invention.