accelerometer

         Accelerometer 

Potentiometric type accelerometer :-

 working principle :-

A potentiometric accelerometer employs a seismic mass, spring arrangement, dashpot,

and a resistive element. 
The seismic mass (potentiometer) is connected between spring and dashpot. The wiper of the potentiometer is connected to the mass.

In the presence of vibration or acceleration, vibrational displacement of seismic mass takes

place with respect to the housing of the device. The displacement of mass is transferred to the

potentiometers through the wiper. Therefore the resistance of the potentiometer changes. 

This change in resistance gives the value of displacement and hence the acceleration.

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spiral type bourdon tube

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                                   Bourdon tube    ( Spiral type) :

working principle of Spiral type bourdon tube:-

The working principle of spiral type bourdon tube is that the applied pressure

is converted into mechanical deflection or displacement. 

The generated displacement will give the value of applied pressure. The materials used in

the construction of bourdon tube are brass, steel and rubber.

Construction and working of Spiral type bourdon tube :

Spiral type bourdon tubes are constructed by winding the long tube into several turns in the

form spiral shape. 

One end of the bourdon tube is opened through which the pressure to be

measured is applied whereas another end is closed. 

The sealed end of the bourdon tube is mechanically connected to a pointer .

Whenever the fluid whose pressure is to be known is applied to the open end of the spiral

tube, it tends to uncoil. 
Due to this a long movement of the tip (end) takes place and this displacement is transmitted to pointer. 
Therefore the pointer moves on the calibrated scale, thereby indicating the applied pressure. When compared to C-type bourdon tube spiral type bourdon tube produces the results with very high accuracy.