Oscillating tool accessory holder mechanism

An oscillating power tool system, comprising:

• a motor;
• an output power shaft extending along an axis and operably connected to the motor, the output power shaft driven in an oscillatory manner by the motor about the axis;
• a flange supported by the output power shaft and fixedly positioned with respect to the output power shaft so as to oscillate with the output power shaft when driven by the motor, the flange including a lower surface defining a first plane;
• a plurality of mounting pins extending from the flange to a location beneath the first plane, the plurality of mounting pins configured such that when an accessory is mounted to the flange, a mounting force is applied directly to the plurality of mounting pins from the accessory at a plurality of locations spaced apart from the first plane;
• and
• a clamping mechanism including
• a spindle axially slideably positioned within a central bore of the output power shaft and rotationally fixed with the output power shaft;
• a foot portion extending orthogonally to the axis and configured to clamp the accessory against the plurality of mounting pins when the accessory is mounted to the flange;
• and
• a spring operably connected to the spindle, wherein the spring is configured to selectively force the foot portion against the accessory when the accessory is mounted to the flange.