Abstract: A height measuring device includes a height measuring sleeve and a distance measuring mechanism. The height measuring sleeve is vertically disposed on the equipment to be measured and includes at least two sleeves which are sleeved and matched with each other. The distance measuring mechanism is provided at bottom or top of the height measuring sleeve. When the lifting mechanism drives the main body rise or fall, the height measuring sleeve extends or retracts as the main body or the lifting mechanism, so that a height information of the main body or the lifting mechanism is obtained according to a height information of the height measuring sleeve measured by the distance measuring mechanism.

Abstract: A braking system for a passenger boarding bridge are provided. The braking system includes a locking member fixedly mounted on the cabin and at least one set of braking assemblies. Each set of the braking assemblies includes an oscillating member rotatably mounted on the cab, an oscillating wheel mounted on the oscillating member and an elastic member having a pre-tightening force. The oscillating wheel cooperates with an outer side of the drive belt to form an abutting force so as to balance the pre-tightening force. The pre-tightening force of the elastic member rotates the oscillating member to a direction of the locking member and cooperates with the locking member in a locking manner to realize braking when the length of the drive belt between the driven wheel and the driving wheel exceeds a preset value or is in a broken state.

Abstract: The present disclosure discloses a braking system and a passenger boarding bridge. The braking system includes a locking member and at least one set of braking assemblies. The locking member is fixedly mounted on the tunnel. Each set of the braking assemblies includes an oscillating member rotatably mounted on the cab, an oscillating wheel mounted on the oscillating member and an elastic member. Wherein the elastic member presents a pre-tightening force. The oscillating wheel cooperates with an outer side of the drive belt to form an abutting force so as to balance the pre-tightening force of the elastic member when the drive belt is in a normal working state. The pre-tightening force of the elastic member rotates the oscillating member to a direction of the locking member and cooperates with the locking member in a locking manner to realize braking when the length of the drive belt between the driven wheel and the driving wheel exceeds a preset value or is in a broken state.