Safety mechanism for door handle

Apparatus comprising

• a pivoting member pivotable about an axis and configured to be operably connected to a device to be operated, the pivoting member having therein an aperture defined by a wall,
• an actuating member manually pivotable about the axis, the actuating member including a hub surrounding a portion of the pivoting member, the hub having therein an opening, and
• a safety mechanism including a manually movable cam member having a detent surface and a driving surface, the cam member movable relative to the hub between an inner position, an outer position and an intermediate position between the inner and outer positions, and the mechanism also including a first spring exerting on the cam member a force biasing the cam member in the direction from the intermediate position to the inner position, and a second spring exerting on the cam member a force biasing the cam member in the direction from the inner position to the intermediate position, the first and second springs having spring forces such that the cam member is in the intermediate position absent external forces,
• wherein, when the cam member is in the intermediate position, the cam member extends partially into the aperture such that if the actuating member is pivoted relative to the pivoting member, engagement between the detent surface and the wall causes the cam member to move against the force of the spring to the outer position,
• wherein, when the cam member is in the outer position, the cam member is withdrawn from the aperture such that pivotal movement of the actuating member does not cause pivotal movement of the pivoting member, and
• wherein, when the cam member is in the inner position, the cam member extends fully into the aperture such that if the actuating member is pivoted relative to the pivoting member, the driving surface of the cam member engages the wall and pivotal movement of the actuating member causes pivotal movement of the pivoting member.

A mechanism for selectively coupling a first moving part with a second moving part such that the first and second moving parts move together, the second moving part having an aperture, the mechanism comprising:

• an engaging member carried by the first part, the engaging member having a detent surface and a load transferring surface, the engaging member being movable between a detent position in which the detent surface is within the aperture of the second moving part, a uncoupled position in which the engaging member is fully retracted from the aperture, and a coupled position in which the load transferring surface is within the aperture;
• a biasing member acting with a biasing force on the engaging member to bias the engaging member into the detent position;
• and
• an actuating member for manually actuating the engaging member to overcome the biasing force of the biasing member and move the engaging member into the coupled position such that the first and second moving parts are coupled for movement together;
• wherein relative movement of the first moving part and second moving part with the engaging member in the detent position results in a component of force acting against the biasing force, such that the biasing force is overcome and the engaging member rides out of the aperture in the second moving member, into the uncoupled position.

A mechanism for selectively coupling a first moving part with a second moving part such that the first and second moving parts move together, the second moving part having an aperture, the mechanism comprising:

• an engaging member carried by the first part, the engaging member having a detent surface and a load transferring surface, the engaging member being movable between a detent position in which the detent surface is within the aperture of the second moving part, a uncoupled position in which the engaging member is fully retracted from the aperture, and a coupled position in which the load transferring surface is within the aperture;
• a biasing member acting with a biasing force on the engaging member to bias the engaging member into the coupled position;
• and
• an actuating member for manually actuating the engaging member to overcome the biasing force of the biasing member and move the engaging member into the detent position such that the first and second moving parts are coupled for movement together;
• wherein relative movement of the first moving part and second moving part with the engaging member in the detent position results in a component of force acting against the biasing force, such that the biasing force is overcome and the engaging member rides out of the aperture in the second moving member, into the uncoupled position.