Abstract: A system for exerting torque on a shaft includes: a spring assembly having; a spring; a companion member to the spring, wherein at least one of the spring and the companion member is in compression and the other of the spring and companion member is in tension; connecting structure for transmitting a force associated with the spring outside of the gear assembly; and a gear train for connecting the connecting structure to the shaft to apply torque to the shaft. A method of exerting torque on a shaft includes: arranging a plurality of spring assemblies arranged in an array around the shaft, each spring assembly having; a spring; connecting structure for transmitting a force associated with the spring; attaching a gear train to the connecting structure; and configuring the gear train to apply the force associated with the spring to the shaft in the form of torque on the shaft.

Abstract: A system for exerting torque on a shaft includes: a spring assembly having; a spring; a companion member to the spring, wherein at least one of the spring and the companion member is in compression and the other of the spring and companion member is in tension; connecting structure for transmitting a force associated with the spring outside of the gear assembly; and a gear train for connecting the connecting structure to the shaft to apply torque to the shaft. A method of exerting torque on a shaft includes: arranging a plurality of spring assemblies arranged in an array around the shaft, each spring assembly having; a spring; connecting structure for transmitting a force associated with the spring; attaching a gear train to the connecting structure; and configuring the gear train to apply the force associated with the spring to the shaft in the form of torque on the shaft.

Abstract: A door hoist includes a bracket, drive sprocket, ring gear, hub assembly, set of planetary gears, and governor shaft. The drive sprocket has a drive sprocket axis. The ring gear is fastened to the drive sprocket. The ring gear has a ring gear axis that is in alignment with the drive sprocket axis. The hub assembly includes a connector to receive a door drive shaft and secure the door drive shaft in a fixed rotational alignment with the hub assembly. The set of planetary gears is rotationally mounted to the hub assembly. The set of planetary gears is configured to mate with the ring gear. The governor shaft includes a sun gear, brake assembly, and link. The sun gear is configured to mate with the set of planetary gears. The brake assembly has an engaged position and a disengaged position. The sun gear is rotationally fixed relative to the bracket in response to the brake assembly being in the engaged position.

Abstract: A door hoist includes a bracket, drive sprocket, ring gear, hub assembly, set of planetary gears, and governor shaft. The drive sprocket has a drive sprocket axis. The ring gear is fastened to the drive sprocket. The ring gear has a ring gear axis that is in alignment with the drive sprocket axis. The hub assembly includes a connector to receive a door drive shaft and secure the door drive shaft in a fixed rotational alignment with the hub assembly. The set of planetary gears is rotationally mounted to the hub assembly. The set of planetary gears is configured to mate with the ring gear. The governor shaft includes a sun gear, brake assembly, and link. The sun gear is configured to mate with the set of planetary gears. The brake assembly has an engaged position and a disengaged position. The sun gear is rotationally fixed relative to the bracket in response to the brake assembly being in the engaged position.

Abstract: A door hoist includes a bracket, drive sprocket, ring gear, hub assembly, set of planetary gears, and governor shaft. The drive sprocket has a drive sprocket axis. The ring gear is fastened to the drive sprocket. The ring gear has a ring gear axis that is in alignment with the drive sprocket axis. The hub assembly includes a connector to receive a door drive shaft and secure the door drive shaft in a fixed rotational alignment with the hub assembly. The set of planetary gears is rotationally mounted to the hub assembly. The set of planetary gears is configured to mate with the ring gear. The governor shaft includes a sun gear, brake assembly, and link. The sun gear is configured to mate with the set of planetary gears. The brake assembly has an engaged position and a disengaged position. The sun gear is rotationally fixed relative to the bracket in response to the brake assembly being in the engaged position.

Abstract: A counterbalance system for an upward acting door including a first casing and a second casing. Each casing includes a spring element disposed therein operable to store and release potential energy in response to movement of the upward acting door between open and closed positions. The first casing is interlockable with the second casing to accommodate and counterbalance upward acting doors of differing weights.

Abstract: A door release mechanism includes a drop wheel coupled to a holding brake sprocket; a brake drive sprocket fixed to a drop wheel coupled with a governor; and a drop arm having a tooth to mesh with the drop wheel. The drop arm has an engaged position and a disengaged position. In the engaged position, the drop arm prevents rotation of the brake drive sprocket; in the disengaged position, the drop arm allows rotation of the brake drive sprocket. The door release mechanism includes a second brake having a brake sprocket rotationally coupled to the brake drive sprocket. The second brake is configured to provide resistance to rotation of the brake sprocket in response to rotation of the brake sprocket exceeding a predetermined braking speed.

Abstract: A door hoist includes a bracket, drive sprocket, ring gear, hub assembly, set of planetary gears, and governor shaft. The drive sprocket has a drive sprocket axis. The ring gear is fastened to the drive sprocket. The ring gear has a ring gear axis that is in alignment with the drive sprocket axis. The hub assembly includes a connector to receive a door drive shaft and secure the door drive shaft in a fixed rotational alignment with the hub assembly. The set of planetary gears is rotationally mounted to the hub assembly. The set of planetary gears is configured to mate with the ring gear. The governor shaft includes a sun gear, brake assembly, and link. The sun gear is configured to mate with the set of planetary gears. The brake assembly has an engaged position and a disengaged position. The sun gear is rotationally fixed relative to the bracket in response to the brake assembly being in the engaged position.

Abstract: A door hoist includes a bracket, drive sprocket, ring gear, hub assembly, set of planetary gears, and governor shaft. The drive sprocket has a drive sprocket axis. The ring gear is fastened to the drive sprocket. The ring gear has a ring gear axis that is in alignment with the drive sprocket axis. The hub assembly includes a connector to receive a door drive shaft and secure the door drive shaft in a fixed rotational alignment with the hub assembly. The set of planetary gears is rotationally mounted to the hub assembly. The set of planetary gears is configured to mate with the ring gear. The governor shaft includes a sun gear, brake assembly, and link. The sun gear is configured to mate with the set of planetary gears. The brake assembly has an engaged position and a disengaged position. The sun gear is rotationally fixed relative to the bracket in response to the brake assembly being in the engaged position.

Abstract: A door mechanism includes a door shaft, a drive sprocket fixed to the door shaft, a holding brake to counter a closing bias of the door, and a holding brake sprocket that is rotationally coupled to the drive sprocket. A freewheel is coupled to the holding brake sprocket to facilitate free rotation of the holding brake sprocket in a first direction. A first brake is coupled to the holding brake sprocket via the freewheel to provide resistance to rotation of the door shaft in a second direction. A door release includes a drop wheel coupled to the holding brake sprocket, a brake drive sprocket, a drop arm and a second brake to provide resistance to the brake sprocket when the brake sprocket exceeds a predetermined braking speed.

Abstract: A door mechanism includes a bracket and a door shaft, rotationally mounted to the bracket, to operate a door. The door mechanism includes a gear assembly having a ring gear, set of planetary gears, sun gear, and drive sprocket. The ring gear fixed to the door shaft. The door mechanism includes a holding brake to counter the closing bias of the door. The door release has an engaged position in which rotation of the door shaft in the second direction is impeded by a first brake; and a disengaged position in which rotation of the door shaft in the second direction is unimpeded by the first brake. The door mechanism includes a link and a second brake. The link is configured to melt in response to a predetermined temperature. The second brake is configured to provide resistance in response to component rotation exceeding a predetermined speed.

Abstract: A door hoist includes a bracket, drive sprocket, ring gear, hub assembly, set of planetary gears, and governor shaft. The drive sprocket has a drive sprocket axis. The ring gear is fastened to the drive sprocket. The ring gear has a ring gear axis that is in alignment with the drive sprocket axis. The hub assembly includes a connector to receive a door drive shaft and secure the door drive shaft in a fixed rotational alignment with the hub assembly. The set of planetary gears is rotationally mounted to the hub assembly. The set of planetary gears is configured to mate with the ring gear. The governor shaft includes a sun gear, brake assembly, and link. The sun gear is configured to mate with the set of planetary gears. The brake assembly has an engaged position and a disengaged position. The sun gear is rotationally fixed relative to the bracket in response to the brake assembly being in the engaged position.

Abstract: A door hoist includes a bracket, drive sprocket, ring gear, hub assembly, set of planetary gears, and governor shaft. The drive sprocket has a drive sprocket axis. The ring gear is fastened to the drive sprocket. The ring gear has a ring gear axis that is in alignment with the drive sprocket axis. The hub assembly includes a connector to receive a door drive shaft and secure the door drive shaft in a fixed rotational alignment with the hub assembly. The set of planetary gears is rotationally mounted to the hub assembly. The set of planetary gears is configured to mate with the ring gear. The governor shaft includes a sun gear, brake assembly, and link. The sun gear is configured to mate with the set of planetary gears. The brake assembly has an engaged position and a disengaged position. The sun gear is rotationally fixed relative to the bracket in response to the brake assembly being in the engaged position.

Abstract: A rolling door including an axle supported by end brackets, a plurality of drum wheels mounted on the axle, a multi-section door adapted to be selectively rolled and unrolled about the drum wheels, a gear wheel mounted on the axle proximate to one of the end brackets, a spring retainer associated with the gear wheel, a torsion spring having a first end operatively attached to the multi-section door and a second end attached to the spring retainer, a pivotally mounted pawl selectively engaging the gear wheel to maintain a selected counterbalance force setting and disengaging the gear wheel to permit adjustment of the counterbalance force setting, and a locking assembly carried on the pawl selectively engageable with the support bracket to lock the pawl in an engaged position.

Abstract: A rolling door including an axle supported by end brackets, a plurality of drum wheels mounted on the axle, a multi-section door adapted to be selectively rolled and unrolled about the drum wheels, a gear wheel mounted on the axle proximate to one of the end brackets, a spring retainer associated with the gear wheel, a torsion spring having a first end operatively attached to the multi-section door and a second end attached to the spring retainer, a pivotally mounted pawl selectively engaging the gear wheel to maintain a selected counterbalance force setting and disengaging the gear wheel to permit adjustment of the counterbalance force setting, and a locking assembly carried on the pawl selectively engageable with the support bracket to lock the pawl in an engaged position.