Highly Elastic Wiper Blade Steel Belt

In one embodiment, the shank portion incorporates a metal that exhibits substantial elastic response under the flexural stress and service conditions encountered by the wiper blade insert. Alternatively, the shank portion utilizes an elongated strip of spring metal.

In a further embodiment, the extrusion die is specially adapted to preform a weakened mid-section of a continuous length of curable elastomer. The resulting mid-section separates not at the nip rollers, but rather along the preformed mid-section into wiper-sized segments.

High Elasticity

The highly elastic wiper blade steel belt can bend more than an inch for every 1 pound of pressure it is subjected to. This makes it an ideal material for windshield wipers because it can flex when encountering belt splices and other irregularities on the road without breaking. The elastic nature of the material also helps it maintain its shape and not fall off the windshield, which can lead to streaking.

The Hyer patents describe a method for forming such flat wiper blades using an extrusion process. They disclose a silicone rubber composition for such purposes that contains about 100 parts of a curable silicone polymer, about 40 parts of filler and from about 0.5 to 2.0 parts of a vulcanizing catalyst. The silicone polymer is derived from one or more polydiorganosiloxanes and has very substantial numbers of saturated side groups and relatively minor amounts of vinyl organic groups (the amount of vinyl in the silicone polymer can range from 0 to 5 mole percent).

In this invention, a continuous length of the curable silicone elastomer is extruded through a special die having a die opening that is shaped to produce a pair of blades joined at a mid-section thereof in edge-to-edge relation. The mid-section is either scored or preformed to produce a weakened portion. The resulting continuous length of wiper blade is then cured. Cold rolled high carbon steel spring steel strip The resulting flat wiper blade is oil resistant, possesses high hardness and tensile strength, and has an elongation of 190%.

High Durability

The unitary, resilient belt wiper blades are welded to a base, frame or like fixed support beneath the conveyor belt lower run and, in use, are self-biased to move into an arced central portion which flattens against the belt, thereby ensuring uniform contact therewith over the major part, if not all, of the bottom surface of that belt. This substantially reduces the offset or eccentricity of loading by up to 50% and, as a result, significantly lowers the bending moment which otherwise would cause the wiper blade tip to curl downward towards the mounting base and buckle.

A more robust wiper blade design is incorporated with a multiradius concave side profile, thicker base section and a high-profile metal mounting insert which combine to substantially reduce the bending moments associated with wiping operations and provide an improved structural profile with a higher moment of inertia. This enables the use of a soft, wear-resistant elastic polymer without risk of blade buckling.

Unlike conventional rubber wiper blades, premium beam blades offer an infinite number of pressure points, making them more resistant to wind lift which can cause them to lose contact with your windshield. This helps your windshield wiper blades resist the forces of nature, so you can see what’s ahead. Check your vehicle manual for the right size blades or try Imperial Supplies’ new Wiper Blade Finder to find your perfect match.

Good Heat Resistance

For those who find that their windshield wiper blades seem to be getting a bit sticky and streaky, there are several things that may cause this. Often, it’s just a matter of dirt or other residue that is stuck to the windshield and must be removed. In addition, there may be a problem with the wiper arm or a connection that must be reworked.

The present invention relates to self-biasing belt wiper blades of unitary or composite construction, and to the method of using them. It involves the flexing of a resilient belt wiper blade into an arc, which in turn causes the central portion of the wiper blade to flatten against the bottom surface of an endless conveyor belt or like belts. This results in intimate contact with and improved scraping of clinging foreign deposits from the bottom surface of the conveyor belt or like belts.

In one form of the invention, a unitary resilient belt wiper blade is of solid or tubular construction, and is bowed at its central portion, as shown in FIGS. 1 and 2. This bending action of the wiper blade is caused by a force which develops when a foreign deposit such as a clump of ice or other material clings to the bottom surface of the conveyor belt or like strands.

Good Abrasion Resistance

The abrasion resistance of the abrasion resistant belt is better than that of conventional rubbers and polyethylene and comparable to that of ultra-high molecular weight polyethylene (UHMW PE). The specific properties required for a particular application are best determined by the Abrasion Resistance Test, ASTM G65. In the present case, the abrasion resistance is optimized for sliding abrasion from dry, rounded quartz aggregate.

A composite self-biased resilient belt wiper blade is provided having a central portion indicated generally at 412 and opposite legs 412a which extend obliquely downward from the center of the leg forming section, to terminate in integral right angle feet as at 412d. Loops 412e are located within the central portion 412c adjacent to each leg. The legs and feet are welded together at their respective ends.

In a simplified embodiment, the ends of the unitary resilient belt wiper blade may be welded to a base, frame or like fixed support beneath a conveyor belt lower Tinplate Sheet supplier run. The bowed central portions of the wiper blade face and flatten against the bottom surface 40 of the belt and engage therewith over a major part, if not all, of the width of the belt lower run.

The wiper blade body 17 has first and second straight wall portions 19 and 20 extending upward from the base to thicken it and add structural rigidity. The straight wall surfaces connect with a curved wall portion 22 which is smoothly and concavely curved to a point 22e at the end of the blade.