21. Inspection and measurement

In industrial situations, the ability to inspect and, if necessary, re­ject quickly is desirable if further errors are to be prevented. The value of microcomputer-controlled inspection equipment lies in moving probes at high speed or using several probes simultaneously, and in an­alysing the reading obtained to produce a final result quickly and with consistent accuracy. For example, in checking turbine blades twenty transducers might be used simultaneously. Immediate indication of “oversize”, “undersize” or (red, orange, green) and a printout is avail­able for permanent record.

The individual readings can be conveniently stored to allow trends, etc. to be identified. This often enables a situation to be altered before faulty work is produced.

For precision engineering an important measurement is surface quality expressed by about twenty parameters (e. g. roundness). The calculation of these parameters is tedious working from a trance of the surface. Traditional surface measurement instruments provide analog output into, say, chart recorders. By interfacing a microcomputer to the output of the instrument, the analysis can be done directly. In this type of application, therefore, there are microprocessor-based surface meas­urement instruments and also “add-on” systems.

Notes:

turbine blade — лопасть турбины

trend — тенденция

precision engineering —точноемашиностроениеfrom a trace of the surface —попроекцииповерхности(наэкран,плоскостьобъективамикроскопаит.д.)chart recorder — самопишущийприбор“add-on” systems —дополнительныеустройства

22. SAFETY ENGINEERING

Accidents to people in industrial enterprises are called industrial traumatism (injury). They occur when workers have not acquired the requisite for skill and lack the necessary experience in handing tools and equipment. Accidents are also caused through neglect of safety rules and regulations in the factories and training workshops.

The purpose of safety engineering is to prevent accidents and to create such conditions of work in industry which will ensure maximum productivity of labour.

When taking up new duties or when first going to work at any in­dustrial enterprise each worker is obliged to acquaint himself thorough­ly with, and to master the safety instructions.

23. ENGINE OPERATION

An automobile, powered by a petrol engine, begins to operate when the driver turns a flywheel connected to the engine crankshaft. As the crankshaft revolves, a mixture of fuel and air is drawn from a carburator into the engine cylinders. The ignition system provides the electric sparks that ignite this mixture. The resultant explosions of the mixture turn the crankshaft, and the engine starts moving. By regulating the flow of the fuel and air with a throttle, the driver controls the rotational speed of the crankshaft.

Cooling, electrical ignition and lubrication systems are of great importance for the good performance of a car. The lights, radio and heater add to the flexibility, comfort, and convenience of the car. The indicating devices keep the driver informed as to engine temperature, oil pressure, amount of fuel, and battery charging rate.

Brakes are of drum and disk types. The steering system consists of a manually operated steering wheel which is connected by a steering col­umn to the steering gear from which linkages run to the front wheels. It is difficult to turn the steering wheel, and special hydraulic power mech­anisms are used to lessen this effort. Suitable springs are used against shocks. These are leaf springs, coil springs, torsion bars and air suspen­sions.