Spring scales for determining force or weight

The spring scale /spring dynamometer (also popularly known as rag or bag scales) is a measuring device for determining weight or force. The weight/force is indicated by the corresponding expansion (“elongation”) of a mechanical coil spring. The linear expansion measured, which is in the linear expansion range, uses Hooke's law, in which the expansion of the spring is proportional to the tensile force.
A spring balance determines the mass via the weight force and has a Scale in kilograms (kg). For spring dynamometers the scale is given in Newton (N). Read more...

Construction of a spring balance

The handy scales have a robust anodized and abrasion-free aluminum tube as well as a long precision scale with high resolution. The spring balances have as standard a tare and zero setting device as well as rotating and swiveling suspension brackets. The mechanical principle is always ready for use and without batteries. The spring balances with an accuracy of +0.3% of the hanging Load have a tare range of 20% of the maximum weighing range and are available in both grams (g) and Newton (N).

The measuring devices are supplied with a hook or clip. The spring scales with a weighing range of 1 to 1000 grams have a clamp as a load-carrying device, while the spring scales with a weighing range of 2.5 kg to 50 kg have a hook.

Assembly is child's play, because this scale consists only of the spring mentioned above, a suspension device at the upper end, a scale with a pointer along the spring travel and a clip or hook at the lower end.

Functions and examples of spring balances

The spring scale is valued primarily because of its uncomplicated handling (with sliding weight scales, sliding weights have to be operated, electronic scales have to be switched on and off again).

The disadvantage of spring scales is the measuring accuracy, which is significantly higher with modern, electronic scales. The gravitational acceleration acting on mechanical scales cannot be compensated for, resulting in inaccuracies of up to 0.3%. For most applications, the spring balance remains an accurate and handy scale.

Drag pointer

The larger models are equipped with a split pointer and handle. The split pointer is a white ring that is pulled over the body and remains in the last position. This ring can be retracted after completion and you can begin the next weighing.

Durability

All spring scales are virtually indestructible under normal use. They are designed so that they can be loaded several million times and do not experience any permanent deformation. Also thanks to the abrasion-free aluminum tube.

Conversion to a pressure transducer

Using the easily adaptable conversion set, you can also turn the spring balances into pressure dynamometers.

Applications

Balances that work according to the spring balance principle are mainly used in industry, in commerce and also in laboratories. Spring balances are also used as teaching aids in physics lessons, showing the weight of bodies in Newtons. The advantage in the medical field is the ability to be stored for 15 hours in acetylene or in an autoclave at +120 °C at 1 bar. Sterilize for 45 minutes. The spring balances do not suffer any mechanical damage. It is precisely their uncomplicated handling and their reliability, coupled with a very low susceptibility to errors, that have ensured their widespread use in the past.

With spring balances from BOSCHE you have a long-lasting, precise device for measuring tensile force.

Practical examples of spring balances:


Animal research: ornithology Weight determination, growth control	Numismatic: Coin scale	Tensile force meter: for determining the tearing force of fasteners	Fire protection: Control of extinguisher fillings	Fishing: Fish scales for determining the weight of fish

Pressure force measurement: Determination of the resistance of push buttons	Read the infusion amount directly thanks to the inverse scale (custom made)	Determination of the closing force of doors with a drag pointer and pressure set	Agriculture: Spring-loaded scale with rotating special hook for enclosing fruits (e.g. suitable for olives of any size).	Speech therapy: Lip closing forces with myofunctional therapy