Miniature Housings for Electronics With Standard Interfaces

A family of general-purpose miniature housings has been designed to contain diverse sensors, actuators, and drive circuits plus associated digital electronic readout and control circuits. Each housing fits within an envelope having dimensions of about 2-1.4 by 1-3.4 by 1.2 in. (about 5.7 by 4.4 by 1.3 cm). Each housing can be secured to a mating carrier by use of screws or epoxy; this mounting scheme helps the housings and their contents to withstand severe vibrations and ensures thermal conduction for dissipation of heat generated during operation of the contained circuitry. The circuits contained in the housings communicate with the external world via standard RS-485 interfaces. Multiple units comprising housings and their contents can easily be electrically connected together in a daisychain arrangement, within which individual units are addressable via the RS-485 bus. Hence, a single master computer connected to the bus can program, or read data from, any or all such units. Examples of such units include small motor drives, programmable thermostats, data loggers, and programmable controllers. There are numerous potential uses for these units in medical equipment, automotive electronics, manufacturing equipment, and robots.