Universal joints are used to transmit power, motion, or both. Cardan joints or Hooke joints are the most common and consists of two yokes, one on each shaft, connected by a cross-shaped intermediate member called the ”spider”. The angle between the shafts is called the operating angle. It is usually constant during operation, but not necessarily so. Good design practice calls for low operating angles, often less than 25°.
Universal joints are available in steel or in thermoplastic body members. For maximum load-carrying capacity, for a given size, a steel universal joint should be selected. Universal joints with thermoplastic body members are used in light industrial applications in which their self-lubricating feature, light weight, negligible backlash, corrosion resistance, and capability for high-speed operation are significant advantages. Ball-jointed universals are used for high-speed operation and for carrying large torques. They are available in miniature and standard sizes.
SDP/SI pioneered the concept of combining the exceptional qualities of selected plastic materials with different metals to create products that incorporate both. “SUPER-PLAST” designs have the following advantages:
• Inexpensive replacement of metal components
• Dampens vibration
• Corrosive and chemical resistant
• Electrically insulated
SDP/SI offers an extensive selection of inch and metric-dimensioned universal joints available in steel, stainless steel, acetal, and acetal with brass spider and inserts as standard catalog items.
The molded universal joints can be manufactured to special requirements:
• Bores molded to accommodate square, “D” shape, or hexagonal shafts
• Shafts molded into the components
• Zero backlash or components with built-in backlash
• Gears, pulleys, or other components molded or assembled to couplings or universal joints