Abstract: Embodiments of the present disclosure provide a datum selection method for minimizing hole position errors in group hole machining of large components, comprising: 1) determining a type of a computer numerical control (CNC) machine tool and establishing a topological structure of the CNC machine tool; 2) establishing a theoretical postural model of a tool center point during a motion; 3) establishing a hole position error model; 4) establishing an average error model of hole positions in group hole machining; and 5) obtaining a machining datum for group holes of corresponding components. For the skeleton and skinned group hole machining of aircraft components, different principles of datum selection are provided respectively, which can effectively improve the positional accuracy of the skeleton or skinned group hole machining, at the same time provides a more scientific and reasonable approach for the datum selection in group hole machining of large components.

Abstract: The present utility model provides a contactor, comprising: a housing, including a first side plate and a second side plate disposed opposite to each other; a static iron core and a movable iron core located inside the housing, a coil bobbin fitted on the static iron core, a coil wound on the coil bobbin, an elastic device located between the coil bobbin and the movable iron core, and a moving contact and astatic contact disposed opposite to each other, wherein the coil bobbin includes a contact end surface facing the movable iron core and a first fixing part and a second fixing part fixed to edges of the contact end surface, length directions of the first fixing part and the second fixing part are parallel to the first side plate and the second side plate, the first fixing part is in contact with and connected to the first side plate, and the second fixing part is in contact with and connected to the second side plate.

Abstract: The present utility model provides a contactor, comprising: a housing, including a first side plate and a second side plate disposed opposite to each other; a static iron core and a movable iron core located inside the housing, a coil bobbin fitted on the static iron core, a coil wound on the coil bobbin, an elastic device located between the coil bobbin and the movable iron core, and a moving contact and astatic contact disposed opposite to each other, wherein the coil bobbin includes a contact end surface facing the movable iron core and a first fixing part and a second fixing part fixed to edges of the contact end surface, length directions of the first fixing part and the second fixing part are parallel to the first side plate and the second side plate, the first fixing part is in contact with and connected to the first side plate, and the second fixing part is in contact with and connected to the second side plate.

Abstract: The present invention relates to the video surveillance field, and discloses a trunk management method and apparatus for video surveillance systems. In the present invention, the connection priority of a surveillance equipment is the highest priority amon/between priorities of all clients, when multiple clients with different priorities access the same surveillance equipment. The connection priority of the surveillance equipment is set as the priority of a new client, if the new client accesses the surveillance equipment and the priority of the new client is higher than the connection priority of the surveillance equipment; the connection priority of the surveillance equipment is remained unchanged, if the priority of the new client is not higher than the connection priority of the surveillance equipment.

Abstract: The present invention relates to the video surveillance field, and discloses a trunk management method and apparatus for video surveillance systems. In the present invention, the connection priority of a surveillance equipment is the highest priority amon/between priorities of all clients, when multiple clients with different priorities access the same surveillance equipment. The connection priority of the surveillance equipment is set as the priority of a new client, if the new client accesses the surveillance equipment and the priority of the new client is higher than the connection priority of the surveillance equipment; the connection priority of the surveillance equipment is remained unchanged, if the priority of the new client is not higher than the connection priority of the surveillance equipment.

Abstract: An electronic fuse circuit for interrupting a current flowing through a power circuit includes: a trip switch structured to open and close to interrupt and permit, respectively, the current flowing through the power circuit; a current sensing circuit structured to sense when a magnitude of the current flowing through the power circuit is greater than a predetermined magnitude; a trip circuit structured to control the trip switch to open and close based on the sensed magnitude of the current flowing through the power circuit; and a processor having a routine structured to monitor a characteristic of the trip circuit and, when the monitored characteristic meets a predetermined criteria, to enter an override mode and control the trip circuit to control the trip switch to open regardless of the magnitude of the current flowing through the power circuit.

Abstract: An electronic fuse circuit for interrupting a current flowing through a power circuit includes: a trip switch structured to open and close to interrupt and permit, respectively, the current flowing through the power circuit; a current sensing circuit structured to sense when a magnitude of the current flowing through the power circuit is greater than a predetermined magnitude; a trip circuit structured to control the trip switch to open and close based on the sensed magnitude of the current flowing through the power circuit; and a processor having a routine structured to monitor a characteristic of the trip circuit and, when the monitored characteristic meets a predetermined criteria, to enter an override mode and control the trip circuit to control the trip switch to open regardless of the magnitude of the current flowing through the power circuit.