Plastics leaf springs

Nickel, H.W. (January 1986). Bushing constmction for a fiber reinforced plastic leaf spring,... 

Ryan, W.E. (December 1985). Method of making a molded fiber reinforced plastic leaf spring, US pat 4, 560,525... 

Composites are being employed in a number of automotive applications. These include racing car bodies as well as regular automobiles. Most automobiles have the lower exterior panels composed of rubbery, plastic blends, and/or composite materials. Corvettes have composite bodies that allow a lightweight vehicle with decent fuel economy and they do not rust. Other parts such as drive shafts and leaf springs in private cars and heavy trucks, antennas, and bumpers are being made from composite materials. 

The first all-around automobile application of composite leaf-springs was made in the Sherpa 200 series van and mini buses built by Freight Rover. These fiber-reinforced plastic (FRP) components for high stress, high-temperature uses were developed by GKN. ICl s Verton, a long-fiber reinforced thermoplastic is also suitable for such applications. 

Figure 12 shows an example of compact compression hardware with improved force distribution. The force is transferred to the end plate hardware by steel or plastic bands. This permits a very short distance from the stack. The band lies on a leaf spring which is nearly flat when the force is applied. As a result the force is not transferred to the end plate at a single point but over a wide area. As this area lies in the center of the plate, the deflection of the plate is much reduced. 

This point was made clearly by Wong, Cowan Farquhar (1985). They imposed slow water stress on 30-day-old Zea mays plants grown in 45 1 plastic bins during early spring where glasshouse vapour pressure deficit was generally about 1.0-1.5 kPa. During the 14 day period the predawn leaf water potential declined from - 0.5 to - 0.8 MPa. Rate of assimilation. 

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