Bobbin winding device and sewing machine

A bobbin winding device comprising:

• a spool shaft to which a small-diameter bobbin or a large-diameter bobbin having a larger diameter and a shorter shaft length than the small-diameter bobbin is mounted;
• an engaging member provided on the spool shaft and having an engaging portion configured to be engageable with the small-diameter bobbin or the large-diameter bobbin mounted on the spool shaft;
• a holder that is integrally rotatable on the spool shaft and is movable in the axial direction of the spool shaft, and the large-diameter bobbin is sandwiched with the engaging portion in the axial direction of the spool shaft at the first position, and the small-diameter bobbin is sandwiched with the engaging portion in the axial direction of the spool shaft at the second position on the base end side of the spool shaft with respect to the first position;
• a switch which detects the completion of winding of a bobbin thread around the small-diameter bobbin or the large-diameter bobbin mounted on the spool shaft;
• a rotating body which is configured to be rotatable around an axis parallel to the spool shaft, and presses the switch by rotating from a non-pressing position separated from the switch to a pressing position via an intermediate position on one side of the rotation direction;
• a contact portion provided on the rotating body and configured to be able to contact the bobbin thread, and is arranged radially outside the core portion of the small-diameter bobbin or the large-diameter bobbin at the non-pressing position, and rotates the rotating body to one side in the rotation direction by being pressed by the bobbin thread wound around the small-diameter bobbin or the large-diameter bobbin;
• an urging member that urges the rotating body on the other side in the rotating direction at the non-pressing position and on one side in the rotating direction at the pressing position, and switches the urging direction with respect to the rotating body at the intermediate position;
• a switching member that is rotatably configured around an axis parallel to the spool shaft and is connected to the urging member, and by rotating from the initial position to the switching position, the intermediate position is changed to one side in the rotation direction of the rotating body, and the bobbin winding mode for the small-diameter bobbin or the large-diameter bobbin is switched from a small-diameter bobbin mode to a large-diameter bobbin mode;
• and
• an adjusting member that operates in conjunction with the rotation of the switching member,
• wherein,
• in the small-diameter bobbin mode, the small-diameter bobbin is allowed to be mounted at a regular mounting position with respect to the spool shaft;
• and
• in the large-diameter bobbin mode, the adjusting member prevents the holder placed in the first position from moving to the second position or moves the holder at the second position to the first position so that the adjusting member prohibits the small-diameter bobbin from being mounted at a regular mounting position with respect to the spool shaft, or prevents the rotation of the holder at the second position.