Multi-panel door system, and dual-synchronization drive assembly for a multi-panel door system

A door system, comprising:

• a door having a plurality of door panels of different widths that are each linearly movable between an open position and a closed position;
• and
• a drive assembly operable to generate a drive power to drive the plurality of door panels of different widths between the open position and the closed position at different speeds in a manner that synchronizes linear movement of the plurality of door panels to fully advance the plurality of door panels to the open position or the closed position simultaneously, wherein the drive assembly includes:
• a dual gear unit including a first gear and a second gear, the first gear and the second gear mounted to a drive shaft;
• a stationary main gear and a stationary secondary gear, the stationary secondary gear rotatable about an axis located between a rotation axis of the stationary main gear and the dual gear unit;
• a first transmission belt consisting of a single belt having a first belt length, and wherein the first belt length is sized so that the first transmission belt extends around and meshes with each of the first gear and the stationary main gear to operatively connect the first gear and the stationary main gear to transmit the drive power from the drive shaft to a first door panel of the plurality of door panels and advance the first door panel between the open position and the closed position;
• and
• a second transmission belt having a second belt length that is less than the first belt length, and wherein the second belt length is sized so that the second transmission belt extends around and meshes with each of the second gear and the stationary secondary second gear to operatively connect the second gear and the stationary secondary gear to transmit the drive power from the drive shaft to a second door panel of the plurality of door panels and advance the second door panel in the same direction as the first door panel between the open position and the closed position.

A drive assembly for a door system that includes a door having a plurality of door panels of different widths that are each movable between an open position and a closed position, the drive assembly comprising:

• a dual gear unit operatively connected to the plurality of door panels of different widths to cause a synchronized linear movement of the plurality of door panels of different widths at different speeds which fully advances the door panels to the open position or the closed position simultaneously, the dual gear unit including a drive shaft, the dual gear unity comprising:
• a rotatable first gear mounted to the drive shaft and operatively connected to a first transmission belt;
• and
• a rotatable second gear mounted to the drive shaft and operatively connected to a second transmission belt;
• the first transmission belt consisting of a single belt having a first belt length sized so that the first transmission belt extends around and operatively engages the rotatable first gear and a stationary main gear to operatively connect the rotatable first gear and the stationary main gear to transmit a drive power to a first door panel of the plurality of door panels which advances the first door panel between the open position and the closed position;
• and
• the second transmission belt having a second belt length that is less than the first belt length, the second belt length sized so that the second transmission belt extends around and operatively engages the rotatable second gear and a stationary secondary second gear to operatively connect the rotatable second gear and the stationary secondary gear to transmit the drive power to a second door panel of the plurality of door panels which advances the second door panel in the same direction as the first door panel between the open position and the closed position, and wherein the stationary secondary gear rotates about an axis that is located between a rotation axis of the stationary main gear and the dual gear unit.