Telescopic cylinders consist of a series of telescopically arranged tubular sections with a cap closing a first end of each section. A second end of each section is mounted with a two-piece cylinder head while an inner tubular member has a plunger pin eye which threads into the tube section. The cylinder heads are threadedly mounted to an outer wall at the second end of each section; they are provided with dynamic and static seal means for sealing and with scraper means for removing debris from a surface along which the dynamic seal means slidably contacts.
Industrial telescoping cylinders may be exposed to a wide range of contaminants, especially when provided on refuse collection trucks or garbage compactors for example. In refuse collection trucks, organic or mineral substances tend to adhere and accumulate on exposed surfaces of the vehicles, such as surfaces of sections of cylinder heads of the telescoping cylinders, where they cook under the action of heat. Such substances stick to surfaces of the cylinder heads and result in rapid damages of the sealing joints thereof, which may result in premature spills and leaks.
Benjamin et al., in the U.S. Pat. No. 4,168,837, disclose a scraper ring for a shaft, which has a scraping edge formed by pinching or piercing a brass member. Wyse, in the U.S. Pat. No. 4,577,363 describes a scraper ring formed of two semicircular mating sections made of a metal such as brass or bronze, or formed of a rigid high strength plastic material, intended to clean a piston rod of a hydraulic cylinder exposed to dirt, mud and ice for example. Such scraper rings are not satisfactory in application involving industrial telescoping cylinders that are exposed to the wide range of contaminants cooked on a tubular surface as discussed hereinabove.
Therefore, there is a need in the art for an improved cleaning assembly for a shaft such as a cylinder member.
USPTO Backgrounds
USPTO Backgrounds