What is used in digital scale to measure object weight?

[ryu2112]

Digital Scale

I was wondering, what device is used in a digital scale to measure the weight of an object. (same precision in scales used in chemistry labs). Are pressure sensors used? I am having a hard time finding these sensors. Any help would be appreciated. thanks

 

[echo47]

Digital Scale

I have a scale that uses strain gauges bonded to a metal beam that flexes under load.

Example and info:
https://sartorius.balances.com/applications/glossary.html

 

[flatulent]

Re: Digital Scale

The technical term for these sensors is "load cell" and you can do a search on the web and find hundreds of suppliers for them.

 

[ryu2112]

Re: Digital Scale

thanks for the helpful replies.

i've been trying to look for load cells which are capable of weighing small objects like coins, but all I can find is from kilograms to pounds.

 

[IanP]

Re: Digital Scale

Try this link:
**broken link removed**
It is about subminiature load cells ..
Reards,
IanP

 

[Tohu]

Re: Digital Scale

Has several method using in digital scale. Can separate in two different groups :
1. direct measurement
2. indirect measurement

First group has a more used, in this group include Load cells with tension sensor, load cells with quartz sensor, Load cells with piezo sensors. Tension sensors using tension element, this is plate with very thinly platinum resistors, when this plate is bend, has change the resistor geometry and the result is a change of resistance. In quartz sensor is using very similar effect, but the sensor change the frequency.

In the second group includes many different position measuring sensors. This is not a special sensor for measuring weight. This measurement method is using when is need to transformate mechanical or electro-mechanical scale to electronic scale. In this scale is used standard principal with ballast, and sensor measure the movement and position. This method is not a very accurate.

Have one more method with seldom use, this is electromagnetic balance method, or electrostatic method. This method is using in some laboratory and scientific scale.

if you want see more information, see links below, sorry but now i can't find links for the quartz sensors.

h**p://www.hbm.com
h**p://www.revere.nl/index/indexp.htm