Referring to the drawings and initially to
The head box (10) has a chamber (11) longitudinally defined therein for receiving the operating system (20) and the adjusting device (30). A series of slats (12) are connected under the head box (10). A first frame (13) and a second frame (13′) are respectively mounted to a bottom of the head box (10) in interval. A lower bar (14) is used as the lowest slat (12) for user to raise/lower the slats (12).
The operating system (20) includes a shaft (21) rotatably and movably extending through a lower portion of each of the first and second frames (13, 13′). A first operating cord (22) has a first end coiled on the shaft (21) and a second end downwardly extending through the head box (10) and the series of slats (12). Lastly, the second end of the first operating cord (22) is secured on a bottom of the lower bar (14). A second operating cord (23) has a first end coiled on the shaft (21) and a second end downwardly extending through the head box (10) and the series of slats (12). Lastly, the second end of the second operating cord (23) is secured on a bottom of the lower bar (14). The second frame (13′) has a roller (26) mounted thereon. A drive device (24) with a spring (not numbered) is disposed in the head box (10) and corresponds to the second frame (13′). A drive cord (25) has a first end sequentially winding the roller (26) and coiled on the shaft (21), and a second connected to the spring in the drive device (24).
The adjusting device (30) includes a adjusting driver (32) mounted in the head box (10) opposite to the drive device (24) and two drive seats (37) respectively rotatably mounted on a top portion of a corresponding one of the two frames (13, 13′). A polygonal shaft (31) longitudinally extends through the two drive seats (37) and engaged to the adjusting driver (32). The adjusting driver (32) has a wheel (33) laterally mounted thereon. An adjusting rope (34) is wound the wheel (33) and extending through the bottom of the head box (10) for user to drive the adjusting driver (32). Each drive sear (37) has a connector (371) formed thereon. A first adjusting cord (35) extends through a corresponding one of the two drive seats (37) and has a middle portion connected to the connector (371) of the corresponding one of the two drive seats (37). The first adjusting cord (35) has two opposite ends respectively extending the bottom of the head box (10) and sequentially connected to two opposite sides of each of the series of slats (12) and the lower bar (14) for adjusting the angle of the series of slats (12). A second adjusting cord (36) extends through a corresponding one of the two drive seats (37) and has a middle portion connected to the connector (371) of the corresponding one of the two drive seats (37). The second adjusting cord (36) has two opposite ends respectively extending the bottom of the head box (10) and sequentially connected to two opposite sides of each of the series of slats (12) and the lower bar (14) for adjusting the angle of the series of slats (12).
The head box (10) has two first through hole (15) defined in the bottom thereof to allow the first operating cord (22) and the second operating cord (23) extending the bottom of the head box (10). The head box (10) has multiple second through holes (16) defined in the bottom thereof to allow the opposite ends of the first adjusting cord (35) and the second adjusting cord (36) extending through the bottom of the head box (10). The head box (10) has a third through hole (17) defined in the bottom thereof to allow the adjusting rope (34) extending through the bottom of the head box (10).
With reference to
With reference to
Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.