Patent ID: 6131642
Filing Date: 2000-10-17
Classification: E06B

Abstract:
A locking device (38) for locking a longitudinally extending roller (12) for a shade (16) of an architectural covering (1), the roller (12) having a circumferential inner surface, said locking device (38) comprising:a center shaft (28) concentrically arranged within the roller;a return spring (32), capable of being operatively interposed between the roller (12) and said center shaft (28), for biasing the roller (12) towards a retracted position of the shade (16);a disc (42) rotatably mounted on said center shaft (28) radially adjacent a first portion (12A) of the circumferential inner surface on the roller (12);at least one detent projection (82, 86) on a second portion (12B) of the circumferential inner surface on the roller (12);a cam member (44), mounted on said center shaft (28), so as to be able to carry out sliding movement transversely of said center shaft (28), between two end positions; said cam member (44) having a lateral cam projection (70, 90) for engaging said detent projection (82, 86); andmeans (47, 48, 49), between said disc (42) and the roller (12), for yieldingly engaging the disc (42) to rotate with the roller (12) in either of two opposite rotational directions;said disc (42) having a face (51) that confronts said cam member (44) and is provided with a guide track (52); andsaid cam member (44) being provided with a pawl (74) engaged in said guide track (52) to move said cam member (44) between said two end positions in response to changes in rotational direction of the roller, whereby the roller may be locked releasably in any position of the shade.