Operating mechanism for furniture parts including a shape memory element

1. An operating mechanism comprising

a drive arrangement ( 30 , 130 , 230 ) adapted to be fixed to one of a moveable furniture part ( 21 ) and a stationary furniture part ( 11 ),

the drive arrangement including:

a drive element in the form of a shape memory element ( 91 , 94 , 95 ) which is heatable to be shortened, and

a spring storage device ( 61 , 261 ) in the form of a tension spring, as well as

a linearly movable carriage ( 50 , 150 , 250 ) guided by the stationary furniture part ( 11 ) to which the drive arrangement ( 30 , 130 , 230 ) is fixed,

wherein the drive element ( 91 , 94 , 95 ) is connected to the furniture part ( 11 , 21 ) to which the drive arrangement ( 30 , 130 , 230 ) is fixed and is guided by the movable carriage ( 50 , 150 , 250 ) and wherein the spring storage device ( 61 , 261 ) interconnects the movable carriage ( 50 , 150 , 250 ) and the furniture part ( 11 , 21 ) to which the drive arrangement ( 30 , 130 , 230 ) is fixed,

so that the drive element

operates directly against the linear stroke force of the spring storage device ( 61 , 261 ) which counteracts an operating stroke of the shape memory element ( 91 , 94 , 95 ), and charges the spring storage device ( 61 , 261 ), which is tensioned by the shortening of the shape memory element upon heating thereof, the movable furniture part ( 21 ) and the stationary furniture part ( 11 ) not being in contact with each other when the drive element is not heated,

the operating mechanism further comprising a coupling element ( 24 , 70 , 270 ) in the form of one of a pin ( 24 ) fixed to the furniture part ( 11 , 21 ) to which the drive arrangement ( 30 ) is not fixed and a lever ( 70 , 270 ) arranged on a pivot bearing ( 75 , 275 ) which is fixed to the furniture part ( 11 , 21 ) to which the drive arrangement ( 130 , 230 ) is fixed and is driveable by the movable carriage ( 50 , 150 , 250 ), so that the movable furniture part ( 21 ) and the stationary furniture part ( 11 ) are brought into temporarily abutting contact with each other via the coupling element ( 24 , 70 , 270 ) by shortening the shape memory element ( 91 , 94 , 95 ),

whereby the movement of the movable furniture part ( 21 ) with respect to the stationary furniture part ( 11 ) is initiated, and further shortening of the memory element ( 91 , 94 , 95 ) moves the movable carriage ( 50 , 150 , 250 ) into a position in which the coupling element ( 24 , 70 , 270 ) is decoupleable from the memory element ( 91 , 94 , 95 ), so that the shape memory element ( 91 , 94 , 95 ), upon cooling down, regains its original length without being connected to the coupling element ( 24 , 70 , 270 ).

2. The operating mechanism according to claim 1 , wherein the shape memory element ( 91 , 94 , 95 ) is shortened by heating for generating the force to operate the drive arrangement ( 30 , 130 , 230 ) and is again elongated upon cooling down.

3. The operating mechanism according to claim 1 , wherein the shape memory element ( 91 , 94 , 95 , 591 , 691 ) is electrically energized to be heated.

4. The operating mechanism according to claim 1 , wherein the shape memory element ( 91 , 94 , 95 ) consists of a wire or a bundle of wires.

5. The operating mechanism according to claim 1 , wherein the shape memory element ( 91 , 94 , 95 ) is provided at its ends with electrical connectors or electrical connecting wires.

6. The operating mechanism according to claim 1 , wherein all components needed for the movement of the movable furniture part ( 21 ) are arranged on one of a support plate and a frame and in a housing ( 31 , 131 , 231 ).

7. The operating mechanism according to claim 1 , wherein the coupling element in the form of a lever is an opening lever ( 70 , 270 ) which is pivotally supported on the stationary furniture part so as to be engageable by a coupling projection ( 45 ) for opening the movable furniture part ( 21 ).

8. The operating mechanism according to claim 1 , wherein the shape memory element ( 91 , 94 , 95 ) consists of a nickel titanium alloy.

9. The operating mechanism according to claim 1 , wherein the shape memory element ( 91 , 94 , 95 ) has an intrinsic two way effect.

10. The operating mechanism according to claim 1 , wherein the movable furniture part ( 21 ) is one of a drawer, a revolving door, a pivotable door, a flap and an extension table.