Drive mechanism and head rail for a blind

A head rail and motor unit assembly for a vertical venetian blind an array of retractable and tiltable slats, the assembly including:

• an elongate head rail having a mechanism at one end for tilting or retracting the slats of the vertical blind along the elongate head rail;
• the mechanism having a rotatable control gear, the rotation of which controls the tilting or retracting;
• wherein the control gear is located at a position along the elongate head rail;
• wherein the head rail includes a housing forming a generally enclosed structure, the housing including an aperture, wherein the housing has an elongate surface, from which the slats are adapted to extend and at least one other elongate surface, in which said aperture is formed;
• and
• a motor unit for detachable attachment to the at least one other elongate surface of the head rail;
• the motor unit having a toothed drive gear for meshing with the control gear through said aperture;
• and
• the mechanism also including a lost motion mechanism comprising:
• first and second components relatively rotatable about a common axis;
• a spacer disposed between the first and second components;
• and a flexible elongate member having ends attached respectively to the first and second components;
• wherein relative rotation of the first and second components causes the flexible elongate member to wrap around the spacer such that the first and second components can rotate relative to one another by an amount determined by the length of the flexible elongate member;
• and wherein the lost motion mechanism is driven by the control gear to tilt or retract the slats.

A head rail and motor unit assembly for a vertical venetian blind having an array of retractable and tiltable slats, the assembly including:

• an elongate head rail having a mechanism at one end for tilting or retracting the slats of the vertical blind along the elongate head rail;
• the mechanism having a rotatable control gear, the rotation of which controls the tilting or retracting;
• wherein the control gear is located at a position along the elongate head rail for operative coupling with a motor unit having a toothed drive gear;
• wherein the head rail includes a housing forming a generally enclosed structure, the housing including an aperture, through which the control gear meshes with the teeth of said toothed drive gear;
• wherein the housing has a first elongate surface, from which the slats are adapted to extend and at least one other elongate surface in which the aperture is formed;
• and wherein
• the motor unit is releasably attached to said at least one other elongate surface of the head rail, wherein the motor unit is a generally elongate structure having an elongate attachment surface for mounting along side the at least one other elongate surface and wherein, proximate the aperture, the at least one other elongate surface has a non-circular opening proximate the drive gear, and the motor unit includes a rotatable latch extending from the attachment surface and insertable through the non-circular opening for rotation so as to secure the motor unit to the head rail.

A head rail and motor unit assembly for a vertical venetian blind having an array retractable and tiltable slats, the assembly including:

• an elongate head rail having a mechanism at one end for tilting or retracting the slats of the vertical blind along the elongate head rail;
• the mechanism having a rotatable control gear, the rotation of which controls the tilting or retracting;
• wherein the control gear is located at a position along the elongate head rail for operative coupling with a motor unit having a toothed drive gear;
• wherein the head rail includes a housing forming a generally enclosed structure, the housing including an aperture, through which the control gear meshes with the teeth of said toothed drive gear;
• wherein the housing has a first elongate surface, from which the slats are adapted to extend and at least one other elongate surface in which the aperture is formed;
• and wherein
• the motor unit is releasably attached to said at least one other elongate surface of the head rail, wherein the mechanism is a drive mechanism including;
• a rotatable tilt drive for tilting the slats or a rotatable retract drive for retracting and deploying the slats;
• and a transmission for rotating the tilt drive or retract drive by rotation means;
• the transmission also including the control gear, and wherein the drive mechanism further includes the rotatable tilt drive and the transmission includes a clutch for rotating the tilt drive;
• the clutch incorporating a first lost motion mechanism whereby, after a predetermined number of rotations in the same direction, transmission by the clutch to the tilt drive is disengaged.