40 Inventive Principles
Replacement of a Mechanical System

a) Replace a mechanical system by an optical, acoustic or olfactory system.

b) Use an electrical, magnetic or electromagnetic field to interact with the object.

c) Replace fields: -> static fields to movable fields, -> fixed fields to those which change in time, -> random fields to structured fields.

d) Use a field in conjunction with ferromagnetic particles.

  1. As an additional warning mechanism for detecting leaks of odourless and/or dangerous gases, a harmless but bad-smelling additive is introduced which is detectable even in very low concentrations.
  2. To increase the adhesive force and density of the layer of metal powder on a thermoplastic object, an electromagnetic field is applied during the coating process.
  3. For the non-destructive monitoring of the degree of setting of polymers, a magnetic powder is added. During setting, the changes in permeability can be measured.