Worm shaft attachment structure for spinning reel

A spinning reel to be mounted to a fishing rod, comprising:

• a handle;
• a reel unit that rotatably supports said handle and is to be mounted to the fishing rod;
• a rotor supported rotatably at a front of said reel unit;
• a spool arranged at a front of said rotor for winding fishing line around its outer circumferential surface, said rotor being for winding fishing line on said spool, said spool being shiftable back and forth;
• a rotor driving mechanism for rotating said rotor in cooperation with rotation of said handle;
• an oscillation mechanism for reciprocating said spool back and forth in cooperation with rotation of said handle, said oscillation mechanism including
• a worm shaft rotatably attached to said reel unit via first and second bearings that are disposed at two ends of said worm shaft, said worm shaft having intersecting helical grooves formed on an outer circumferential surface thereof,
• a slider that moves back and forth along said worm shaft, and an intermediate gear that is fixedly coupled to a front end of said worm shaft, said worm shaft being;
• and
• a worm shaft attachment structure including
• a mechanism attachment portion formed unitarily with said reel unit, said mechanism attachment portion having formed thereon a first attachment portion, to which a rear end of the worm shaft being mountable, said first attachment portion having an aperture portion and a bearing mounting portion that is depressed from said aperture portion in a first direction, which intersects with a rotation axis direction of said worm shaft, said bearing mounting portion being able to come into contact with an outer circumferential surface of said first bearing to which a rear end of said worm shaft is attachable, the rear end of the worm shaft being mountable to said bearing mounting portion, and
• a locking member that is mounted detachably to said first attachment portion so as to close said aperture portion and to restrict shifting of said first bearing in the first direction by abutting against the outer circumferential surface of said first bearing.