Making rumble strips from reclaimed tire tread strips

#This invention relates to the use of reclaimed discarded tire carcasses to produce tread strip products thus removing discarded tires from the environment thereby to prevent the breeding of disease carrying mosquitos in discarded tread carcasses, and more specifically it relates to the processing of tire casing tread strips to lie flat in an unstressed condition upon a flat surface, typically a driving surface to thus serve as acoustic warning devices for encountering vehicle tires known as rumble strips, which when adhered in patterns upon a flat driving surface audibly warn drivers of upcoming driving conditions as a car passes over the rumble strips, or other products such as multi-layered parking stop assemblies for engaging vehicle tires in a static condition.

#As taught in U.S. Pat. No. 4,813,811 issued to W. B. Adams on Mar. 21, 1989, for PREFABRICATED PAVEMENT DEVICES, rumble strips are formed as shaped preformed units of paving material, typically blacktop or bituminous, which is difficult to form with long wearing sharp leading edges for audibly encountering overrunning tires of a moving vehicle. These disclosed rumble strips are pre-fabricated into self standing units formed from a pavement mixture and supplied with a lowermost adhesive outer layer for adhering to the previously formed similar paving material of a road surface. The preferred embodiment of this assembly has two preformed layers of pavement material separated by an internally disposed fortifying web of wire mesh or the like. It is noted that these rumble strips cannot be removed non-destructively for further use for example in the wintertime when they would be damaged by snow plows.

#In U.S. Pat. No. 4,490,069 issued to R. P. Cushman, et al. on Dec. 25, 1984 for PORTABLE HIGHWAY WARNING APPARATUS, there is disclosed a network of rumble strips formed into a multi-strip mat of several substantially parallel rumble strips made as a unit from a resilient composition with an area of nearly one-hundred square feet defining a pattern of slots approximately six inches by forty inches separated to produce gaps of about eight inches. This type of mat is inconsistent with the requirements for rumble strips set up by State Highway authorities, and is difficult to handle and install because of the size. Furthermore such mats would not be useful at high overrunning vehicle speeds requiring much greater spacing between successive strips.

#In the accompanying drawings, wherein like reference characters signify similar features throughout the various views:

#FIG. 1 is an end view sketch in section of a typical discarded tire carcass for illustrating how the exterior tread pattern strip is derived in accordance with this invention,

#FIG. 2 is a plan view sketch of lengths of tire tread strips employed in a rumble strip application upon a driving surface in accordance with this invention,

#Preferred dimensions for rumble strips are five and one-half inches in width (w), one-half inch thick (h). Various lengths are produced by fastening five or six foot length tread strips or portions thereof derived from typical discarded tire casings into respective end to end arrays.

#The long-life steel-belting reinforced elastic rubber leading edges of the rumble strips, which protrude above the roadway surface, present ideal acoustic warning signals when impacted by overrunning vehicle tire treads These rumble tread strips lie flat upon the road surface and thus are adhered securely thereto at opposite edges without the presence of conflicting elastic forces residual in the tread strips from their prior tire manufacturing stage that might tend to loosen % adhesion of the strips particularly at the critical edges receiving the impact of overrunning vehicle tires at high speeds. Thus these tough resilient tire tread strips have very long life expectations in use as rumble strips thanks to straight line tread strip edges simply and firmly secured to the roadway surface without counteracting residual elasticity by a low-cost pressure sensitive adhesive coating retained upon the lower surface opposite to the protruding tread.

#The simple procedure afforded by this invention for processing the reclaimed tire strips in a form that inherently lies flat in a relaxed condition without any significant retained elastic memory is discussed with reference to the cross section sketch of FIG. 1.