Patent ID: 8215241
Filing Date: 2012-07-10
Classification: A47B,B60N,Y10T

Abstract:
1. A vertical linear actuator mechanism for positioning a load at a desired elevation above a support surface, said vertical linear actuator mechanism comprising an electric motor having a drivable shaft, a gear assembly coupling interconnecting said drivable shaft to a linear extendable mechanism having a load connector at a top end thereof, a position sensing gear coupled to said gear assembly coupling to detect the position of said load connector relative to said support surface, said position sensing gear providing position signals to a motor controller circuit which monitors the position of said load connector and controls the operation of said electric motor, a drive override means coupled to said gear assembly coupling to impart a drive to said gear assembly coupling to operate said linear extendable mechanism in the absence of power supply to said electric motor, said drive override means having an override shaft gear coupled to said gear assembly coupling, said override shaft gear having a drivable gear secured thereto, and a drive gear supported for disconnectable engagement with said drivable gear, said drive gear being normally biased at a disengaged position with respect to said drivable gear, and external drive means to impart a pushing force to engage said drive gear with said drivable gear and a rotational force to impart a rotation to said override shaft and said pear assembly coupling to displace said load relative to said support surface.