Pressure-retaining cap screwing and unscrewing device for marine natural gas hydrate pressure-retaining rock-core barrel

A pressure-retaining cap screwing and unscrewing device for a marine natural gas hydrate pressure-retaining rock-core barrel, wherein the pressure-retaining cap screwing and unscrewing device comprises a cap-unscrewing chuck, a support cylinder, a pressure-retaining cap screwing and unscrewing head, a spring, a screwing and unscrewing shaft, and a pressure-retaining cap screwing and unscrewing sleeve, a reducer and a motor;

• an input shaft of the reducer is connected to the motor, an output shaft of the reducer is the screwing and unscrewing shaft which is a tubular structure with a plurality of guide holes provided on a side wall thereof;
• a bottom of the screwing and unscrewing shaft is fixed with a connecting head;
• an end of the pressure-retaining cap screwing and unscrewing head facing the screwing and unscrewing shaft is provided with a blind hole, a top of the blind hole is provided with a guide hole, the top of the blind hole is connected to a boss on a side wall of the screwing and unscrewing shaft through a spring, a top surface of the pressure-retaining cap screwing and unscrewing head is provided with a plurality of forks, the pressure-retaining cap screwing and unscrewing head is coaxial with the screwing and unscrewing shaft;
• the pressure-retaining cap screwing and unscrewing sleeve is mounted on the screwing and unscrewing shaft and is located outside of the pressure-retaining cap screwing and unscrewing head, a guide plate on an outer wall of the pressure-retaining cap screwing and unscrewing head is mounted in a guide groove of the pressure-retaining cap screwing and unscrewing sleeve;
• the support cylinder is mounted on the reducer and is located outside of the pressure-retaining cap screwing and unscrewing sleeve;
• and a top of the support cylinder is mounted with the cap-unscrewing chuck.