Bag sealing apparatus and bag sealing method

A bag sealing method comprising the steps of:

• positioning a bag at a sealing process position;
• causing relative movement between a first sealing member and a second sealing member from an open position to a closed position in such a manner that the first sealing member and the second sealing member nip the bag positioned at the sealing process position to perform a sealing process of the bag;
• measuring vibration of at least one of the first sealing member and the second sealing member by a vibration measurement device;
• and
• determining quality of the sealing process according to a measurement result of the vibration measurement device from before the first sealing member and the second sealing member reach the closed position to after the first sealing member and the second sealing member reach the closed position,
• wherein the relative movement between the first sealing member and the second sealing member from the open position to the closed position is performed in such a manner that an absolute value of acceleration of vibration which occurs in the at least one of the first sealing member and the second sealing member by placing the first sealing member and the second sealing member in the closed position as a result of the relative movement is larger than an absolute value of acceleration of vibration which occurs in the at least one of the first sealing member and the second sealing member in a state where the first sealing member and the second sealing member are placed in the open position.