Simple Screw Jack

Features

• Low cost, effective teaching
• Self-contained
• Bench mounted
• Introduction to simple machines
• Determination of velocity ratio mechanical advantage and efficiency
• Overhauling
• Three year warranty

Range of Experiments

1. Experimental determination of velocity ratio and comparison with calculated value
2. Determination of variation with load of:
   
   • 1. effort
   • 2. friction
   • 3. efficiency
     
3. Limiting efficiency of the machine

Description

This simple screw jack is a 220 mm diameter turntable fitted with a 30 mm x 6 mm pitch screw is supported in a heavy cast iron base. The apparatus is stood on a firm bench and a cord and weight hanger are wound round the rim of the turntable and hung over the pulley. The pulley runs on ball bearings to reduce friction to a minimum.

This equipment is part of a range designed to both demonstrate and experimentally confirm basic engineering principles. Great care has been given to each item so as to provide wide experimental scope without unduly complicating or compromising the design. Each piece of apparatus is self-contained and compact. Setting up time is minimal, and all measurements are made with the simplest possible instrumentation, so that the student involvement is purely with the engineering principles being taught. A complete instruction manual is provided describing the apparatus, its application, experimental procedure and typical test results.