Abstract: The present disclosure is directed to stress-responsive compositions comprising (1) at least one (co)polymer comprising at least one mechanophore comprising at least one thiocarbonylthio functional group or derivative thereof and (2) at least one compound comprising at least one functional group capable of reacting with a free radical, The present disclosure is also directed to articles, coatings, and 3D printing binders comprising such stress-responsive compositions, as well as to processes of imparting the abilities of forming and maintaining protective barriers and mechanical self-healing to such articles, coatings, and 3D printing binders by incorporating such stress-responsive compositions therein.

Abstract: The present disclosure is directed to stress-responsive compositions comprising (1) at least one (co)polymer comprising at least one mechanophore comprising at least one thiocarbonylthio functional group or derivative thereof and (2) at least one compound comprising at least one functional group capable of reacting with a free radical, The present disclosure is also directed to articles, coatings, and 3D printing binders comprising such stress-responsive compositions, as well as to processes of imparting the abilities of forming and maintaining protective barriers and mechanical self-healing to such articles, coatings, and 3D printing binders by incorporating such stress-responsive compositions therein.

Abstract: The invention relates to a method for driving an electric motor (1) which is employed, in particular, in manually guided electric tools, such as drilling machines, screwing machines or the like. Variable pulses of an electric voltage are applied to the electric motor (1) in such a way that the rotor of the electric motor (1) moves at a rotational speed which can be set. In order that the rotor of the electric motor (1) moves intermittently or abruptly, at least parts of at least individual pulses are blanked by superposition of a pulse interval having a zero voltage. A circuit arrangement for a method of this type has control electronics (5) and an electronic power switch (4), such as a triac, a transistor, an IGBT or the like, which is switched by the control electronics (5) in such a way that the variable pulses can be applied to the electric motor (1) via the electronic power switch (4).

Abstract: An electrical switch, particularly for a breaking circuit includes first and second changeover switches. The first and second changeover switches each comprise first and second stationary contacts and a switching contact. A plunger is operatively connected to a rocker for causing the rocker to pivot between a non-operated position and an operated position. The second stationary contacts are associated with the non-operated position of the plunger. A spring is connected between the rocker and the switching contacts. The spring is arranged on the rocker and on the switching contacts so that at least when switching over from the second stationary contacts to the first stationary contacts the switching contacts are lifted off the second stationary contacts essentially synchronously.

Abstract: A braking circuit for an electric motor includes a braking device for being connected in a circuit for braking the electric motor, a braking switch including first and second changeover switches for switching between a motor mode and a braking mode, and a control device. Switching contacts of the first and second changeover switches are switched between a first position for contacting, respectively, first stationary contacts of the first and second changeover switches in the motor mode, and a second position for contacting, respectively, second stationary contacts of the first and second changeover switches in the braking mode.