A personnel access door assembly of an opposing wing of a mine ventilation door. The personnel access door includes a frame including a top portion, a bottom portion, a first post portion and a second post portion, the top frame portion and the bottom frame portion coupled to respective top and bottom ends of the first post and second post portions. The personnel access door further includes sets of trolley wheels affixed to the top or bottom of the frame to engage a top rail or bottom rail affixed on the opposing wing.

An oven appliance includes a cabinet that defines a chamber. A pair of doors is rotatably mounted to provide selective access to the chamber of the cabinet. The pair of doors is connected with a linkage assembly such that the doors rotate open and closed simultaneously. The linkage assembly includes a spur gear that engages another gear of the linkage assembly. The spur gear can hinder unwanted rotation of the pair of doors or compress the pair of doors against a seal.

A door actuation system may include an actuation device to move a first door leaf and a second door leaf between an open and a closed position. The actuation device may provide an open preload force in the open position. The actuation device may provide a closed preload force in the closed position. The system may include one or more of: a first engagement member that may contact the actuation device and may allow movement of the actuation device to adjust the open and closed preload force; or the actuation device may be coupled with the first door leaf by a first rod and the second door leaf by a second rod, at least one of the first or second rod may adjust a length of the first or second rod to maintain the open preload force in the open position and the closed preload force in the closed position.

A vehicle door element (120, 122) for reversibly closing at least part of a body opening (102) on a vehicle (100) comprises a door leaf (124, 126) and at least one guide arm (128, 130, 132, 134) which includes a door-side portion and a vehicle-side portion, wherein the door-side portion of the guide arm (128, 130, 132, 134) is mounted on the door leaf (124, 126), and the vehicle-side portion of the guide arm (128, 130, 132, 134) includes connecting means (140, 142, 144, 146) which are configured for shiftably connecting the vehicle door element (120, 122) to the vehicle (100). The connecting means (140, 142, 144, 146) comprise at least one first connecting means (140, 142) which is configured for shiftable connection to a first guide rail (150, 152) of a vehicle door system (110) of the vehicle (100), and at least one second connecting means (144, 146) which is configured for shiftable connection to a second guide rail (154, 156) of the vehicle door system (110) of the vehicle (100). A sensor device (500) for a vehicle door system (110) comprises a sensor unit (510), an adjusting device (520), and a control unit (530) which is configured to control the adjusting device (520) in dependence on the position of at least one vehicle door element (120, 122) of the vehicle door system (110).

A door assembly for a fuselage of an aerial vehicle is described, including a pair of complementary door pieces, and an actuation mechanism that includes a first transmission member. The first transmission member actuates either one or both door pieces for portions thereof to be in a sliding action with respect to the fuselage while maintaining close conformity thereto as either one or both of them are actuated to either meet or separate. Further disclosed are various embodiments of the door assembly, and a related aerial vehicle and system for delivering goods.

An embodiment integrated operating apparatus for different types of gates includes a driving motor, a main shaft rotatable by the driving motor, a first clutch portion at a first side of the main shaft and configured to selectively transmit power to a first gate of a vehicle, the first clutch portion including a first clutch and a first gear selectively engaged with each other, and a second clutch portion at a second side of the main shaft and configured to selectively transmit power to a second gate of the vehicle, the second clutch portion including a second clutch and a second gear selectively engaged with each other, wherein the first and second gates are configured to be independently operated based on the first clutch portion being in an engaged state or a released state and the second clutch portion being in the engaged state or the released state.