Depth adjustment for a fixed base router

A fixed base router comprising:

• a base having a lower planar surface, an upper end, a central bore and a handle affixed thereto;
• an adjusting ring rotatably affixed to the base upper end, coaxial with the central bore, the adjusting ring having an internal thread formed therein and a series of gear teeth defining a ring gear;
• a motor housing including a motor secured therein for imparting rotational movement to a tool holder extending from the motor housing, the motor housing having an external thread formed thereabout, being threadably engaged with the adjusting ring internal thread, and the motor housing being adapted to prevent rotation of the motor housing relative to the base such that rotation of the adjusting ring axially translates the motor housing relative to the base;
• and
• a pinion gear journaled for rotation relative to the base and engaged with the ring gear, the pinion gear having a dial which rotates with the pinion gear relative to the base;
• wherein one of the base and dial includes a scale, and the other of the base and dial includes an indicator for indicating fine adjustment of the motor housing axial position relative to the base.

A fixed base router comprising:

• a base having a lower planar surface, an upper end, a central bore, a pin projecting into the central bore, and a handle affixed to the base;
• an adjusting ring rotatably affixed to the base upper end, coaxial with the central bore, the adjusting ring having an internal thread formed therein and a series of gear teeth defining a ring gear;
• a motor housing including a motor secured therein for imparting rotational movement to a tool holder extending from the motor housing, the motor housing having an external thread formed thereabout, being threadably engaged with the adjusting ring internal thread, and the motor housing including a longitudinal slot formed therealong and cooperating with the pin on the base for preventing rotation of the motor housing relative to the base such that rotation of the adjusting ring axially translates the motor housing relative to the base;
• and
• a pinion gear journaled for rotation relative to the base and engaged with the ring gear, the pinion gear having a dial which rotates with the pinion gear relative to the base;
• wherein the adjusting ring includes a scale and the base includes an indicator for indicating coarse adjustment of the motor housing axial position relative to the base;
• wherein the dial includes a scale and the base includes an indicator for indicating fine adjustment of the motor housing axial position relative to the base;
• and
• wherein a user may rotate the adjusting ring for coarse adjustment of the motor housing axial position relative to the base, and the user may rotate the dial for fine adjustment of the motor housing axial position relative to the base.

A fixed base attachment for a router, the fixed base attachment comprising:

• a base having a lower planar surface, an upper end, a central bore and a handle affixed to the base, the central bore being sized to receive an externally threaded motor housing which includes a motor secured therein for imparting rotational movement to a tool holder extending from the motor housing, and the central bore being adapted to prevent rotation of the motor housing relative to the base;
• an adjusting ring rotatably affixed to the base upper end, coaxial with the central bore, the adjusting ring having an internal thread formed therein for threadably cooperating with a motor housing external thread such that rotation of the adjusting ring axially translates the motor housing relative to the base, and the adjusting ring having a series of gear teeth defining a ring gear;
• and
• a pinion gear journaled for rotation relative to the base and engaged with the ring gear, the pinion gear having a dial which rotates with the pinion gear relative to the base;
• wherein one of the base and dial includes a scale, and the other of the base and dial includes an indicator for indicating fine adjustment of the motor housing axial position relative to the base.