Abstract: A drive mechanism for a dry shaver comprising a shear foil and a cutter reciprocatory relative to the shear foil includes a single-phase synchronous motor having a drive shaft. A cam is mounted on the drive shaft, and a transmission roller is constantly in contact with the cam. The surface of at least one of the cam and the transmission roller is provided with a layer approximately 1 mm in thickness of an elastic material.

Abstract: The invention relates to a drive mechanism which comprises a single-phase synchronous motor (5) for converting the rotation of the motor shaft (3) into a pulsating axial movement by means of an eccentric cam (25). The motor shaft (3) carries a coaxial cylindrical body (13) whose eccentric cam (25) co-operates with a piston rod. The drive-shaft system comprising the motor shaft and body is supported in a multiple bearing comprising a broad-area bearing (23) for the circumferential surface (21) of the cylindrical body (13) and a shaft bearing (19) for the shaft end (15) which projects from the body (13) at the end which is remote from the motor (5). The end portion (29) of the piston rod is guided so as to be axially slidable.

Abstract: An electrically driven appliance such as a citrus press comprises a drivable tool; a self-starting single-phase synchronous motor including a diametrically magnetized permanent-magnet rotor forming a rotor field and positioned between two stator poles forming a stator field; and a drive mechanism arranged between the motor and the tool, for driving the latter, such mechanism including a plurality of drive elements each engaging the adjacent element or elements. A stalling device coacts with one drive element having a pair of stops, the stalling device including a member alternately engageable with such stops after a specific number of revolutions of the rotor in either direction of rotation, such engagement effecting stalling of the rotor and automatic reversal of the direction of the rotation of the rotor.

Abstract: In a return stop for a self-starting synchronous motor (1) having an inert mass (9) which is arranged coaxially with a shaft (6) operatively connected to the motor, is rotatable with respect to the shaft, is positioned on the shaft in axial direction and is coupled to the shaft via a helical spring (10) extending coaxially with the shaft, one end (11) of the helical spring being fixedly connected to the inert mass, it is ensured that the helical spring is loosely disposed on the shaft together with the inert mass, the helical spring being connected to the shaft solely by means of friction contact (FIG. 1).

Abstract: In a dry-shaving apparatus which is adapted to be connected to an a.c. source and which comprises at least one reciprocating cutter, there is provided a self-starting single-phase synchronous motor for driving the cutter. Via at least one drive mechanism, which couples the drive spindle of the motor to the cutter and which converts the rotary movement of the drive spindle into a reciprocating movement of the cutter, the cutter is made to occupy substantially one of the two extreme positions in its reciprocating movement in those positions of the rotor of the motor in which the driving torque has zero value.

Abstract: A dryshaving apparatus in which a shaving head and an oscillating-armature motor constitute an assembly. This assembly is mounted in the housing of the dryshaving apparatus by elastic elements only, at least one elastic element being a strip-shaped integral hinge extending transversely to the oscillating movement and connected at one end to the assembly and at its other end to the housing. The assembly together with the elastic elements has a mechanical resonant frequency less than the oscillation frequency, divided by .sqroot.2, of the parts of the assembly performing the oscillating movement.