Patent ID: 6779634
Filing Date: 2004-08-24
Classification: B66B

Abstract:
A dumbwaiter comprising:a tower assembly defining a vertical track; a container for receiving and delivering materials, the container slidably coupled to the track for vertical movement of the container between vertically spaced apart positions; a pair of upper sheaves mounted at the top of the tower assembly, wherein the upper sheaves are rotatably coupled to a sheave mount, the sheave mount pivotally mounted at the top of the tower assembly to thereby respond to a change in length of either cable by pivoting to retain a balanced load on each cable; a pair of lower sheaves mounted at the bottom of the tower assembly; and a pair of lifting cables each having a first end mounted to the container and extended there from over one of the upper sheaves and extended there from to one of the lower sheaves, a second end of each cable attached to and wound onto the corresponding one of the lower sheaves, the lower sheaves fixedly mounted to a rotatable cylindrical shaft, the cylindrical shaft encasing a drive motor and engaged by the drive motor for selective rotation of the shaft and accordingly the lower sheaves to thereby wind and unwind the lifting cables to selectively raise and lower the container.