Safety Mechanism for Locks

A security device for a lock, comprising:

• a grip portion or knob which is freely rotatable in a resting state, and is adapted to be coupled to a locking member of the lock in an open state or in a closed state, wherein
• at least one radially guided displaceable flyweight (13) is coupled to the grip portion or knob (1),
• said flyweight (13) engages with a fixed portion (11) of the lock, and blocks any further rotary movement above a defined number of revolutions of the grip portion or knob (1) per unit time,
• the flyweight (13) can be displaced from a first locking position radially outwards into a second locking position,
• the grip portion or knob (1) is connected to a shaft (2) which dips into a housing of the lock,
• said shaft (2) comprises at least one radial opening (9) in which the flyweight (13) is arranged with a center of gravity located outside an axis of rotation (10) of the shaft (2),
• a recess or groove (11) is arranged in the housing (12) of the lock, into which recess or groove (11) the flyweight (13) dips during a radially outward movement of the flyweight (13),
• the shaft (2) is configured as a hollow shaft, and said shaft (2) is connected rotationally fixedly to a coupling shaft (3) which passes through the lock for coupling with a locking member (7) of the lock,
• the flyweight (13) is mounted in an elongated hole (9) of the shaft,
• the flyweight (13) is held in said elongated hole (9) of the shaft (2) by interposed spring-mounted locking balls (14),
• the elongated hole (9) comprises walls having grooves (15) shaped to engage the locking balls (14) in a radially inner resting position and in a radially outer locking position,
• each of said at least one flyweight (13) has a beveled edge (17) in an axial section of the flyweight (13), said beveled edge (17) being shaped to press the flyweight (13) from the second radially outer locking position into the first resting position by turning in a direction opposite to a direction of rotation effecting locking of the lock, and
• neighboring or opposite flyweights (13) of said at least one flyweight (13) in a circumferential direction have sloping surfaces (17), said sloping surfaces (17) being shaped to effect a release of the blocking during two rotating movements in respectively opposite directions of rotation.