RETENTION FLANGE FOR POWER TOOL

1 . A power tool comprising:

a housing;

an electric motor housed within the housing;

an output spindle rotatably driven by the electric motor, wherein the output spindle defines a longitudinal axis and includes a threaded portion near a distal end thereof and an annular rim integrally extending radially therefrom at a distance from the threaded portion;

a retention flange including a radially-oriented disc-shaped portion having a center through-hole through which the output spindle extends and a cylindrical wall peripherally extending from the disc-shaped portion around the output spindle, wherein the disc-shaped portion is located between the distal end and the annular rim, and the cylindrical wall extends around the annular rim;

at least one spring member engaging a first surface of the annular rim on one end and the disc-shaped portion on another end to bias the retention flange in a direction away from the annular rim; and

a retention member engaging the retention flange and the annular rim configured to restrain an axial displacement of the retention flange away from the annular rim due to the biasing force of the at least one spring member.

2 . The power tool of claim 1 , wherein, as a tool accessory is tightened on the threaded portion of the output spindle, the tool accessory forces the retention member to move in the direction of the annular rim.

3 . The power tool of claim 1 , wherein the retention member engages a second surface of the annular rim facing away from the at least one spring member.

4 . The power tool of claim 3 , wherein an inner surface of the cylindrical wall of the retention member includes an annular recess, and wherein the retention member comprises a retaining ring received within the annular recess of the retention member, the retaining ring coming into selective contact with the second surface of the annular rim of the output spindle to limit the displacement of the retention flange away from the annular rim.

5 . The power tool of claim 4 , wherein the retention member further comprises an annular shoulder formed by a radial projection on the inner surface of the cylindrical wall radially in line with the at least one spring member, the annular shoulder coming into selective contact with the first surface of the annular rim of the output spindle to limit the displacement of the retention flange towards from the annular rim.

6 . The power tool of claim 1 , further comprising a motor spindle rotatably driven directly by the motor, a gear case mounted on the housing that receives an end of the motor spindle, and a bearing supported by the gear case, wherein the output spindle is received from a lower end of the gear case into the bearing into engagement with the motor spindle.

7 . The power tool of claim 6 , wherein the motor spindle is at a 90 degree angle relative to the output spindle.

8 . The power tool of claim 1 , wherein the at least one spring member comprises one or more Belleville discs.

9 . The power tool of claim 1 , wherein a diameter of the annular rim of the output spindle is greater than a diameter of the at least one spring member, but smaller than a diameter of the cylindrical wall of the retention flange.

10 . The power tool of claim 1 , wherein the retention flange includes a flat wall protruding inwardly from the cylindrical wall that engages a corresponding flat wall of the annular rim of the output spindle to rotationally fix the retention flange to the output spindle.

11 . The power tool of claim 1 , wherein the cylindrical wall of the retention flange includes a plurality of openings and the annular rim of the output spindle includes a plurality of radial projections configured to be fittingly received into the plurality of openings to rotationally fix the retention flange to the output spindle.

12 . A power tool comprising:

a housing;

an electric motor housed within the housing and rotatably driving a motor spindle;

a gear case mounted on the housing;

an output spindle received at least partially within the gear case, wherein the output spindle defines a longitudinal axis and includes a first distal end to which a tool accessory is secured, a second distal configured to engage the motor spindle, and an annular rim integrally extending radially from the output spindle between the first distal end and the second distal end;

a bearing having an inner race secured to the output spindle above the annular rim and an outer race secured to the gear case;

a retention flange including a radially-oriented disc-shaped portion having a center through-hole through which the output spindle extends and a cylindrical wall peripherally extending from the disc-shaped portion around the output spindle, wherein the disc-shaped portion is located between the first distal end and the annular rim, and the cylindrical wall extends around the annular rim; and

at least one spring member disposed between the annular rim and the retention flange to apply a downward biasing force the retention flange away from the annular rim; and

a retention member engaging the retention flange and the annular rim configured to restrain a downward movement of the retention flange away relative to the annular rim along the longitudinal axis due to the biasing force of the at least one spring member.

13 . The power tool of claim 12 , wherein the output spindle includes a threaded portion at the first distal end, and as the tool accessory is tightened on the threaded portion, the tool accessory applies an upward force to the retention member in the direction of the annular rim.

14 . The power tool of claim 12 , wherein an inner surface of the cylindrical wall of the retention member includes an annular recess, and wherein the retention member comprises a retaining ring received within the annular recess of the retention member, the retaining ring coming into selective contact with an upper surface of the annular rim of the output spindle to limit the downward movement of the retention flange.

15 . The power tool of claim 14 , wherein the retention member further comprises an annular shoulder formed by a radial projection on the inner surface of the cylindrical wall radially in line with the at least one spring member, the annular shoulder coming into selective contact with a lower surface of the annular rim of the output spindle to limit an upward movement of the retention flange.

16 . The power tool of claim 12 , wherein the motor spindle is at a 90 degree angle relative to the output spindle.

17 . The power tool of claim 12 , wherein the at least one spring member comprises one or more Belleville discs.

18 . The power tool of claim 12 , wherein a diameter of the annular rim of the output spindle is greater than a diameter of the at least one spring member, but smaller than a diameter of the cylindrical wall of the retention flange.

19 . The power tool of claim 12 , wherein the retention flange includes a flat wall protruding inwardly from the cylindrical wall that engages a corresponding flat wall of the annular rim of the output spindle to rotationally fix the retention flange to the output spindle.

20 . The power tool of claim 12 , wherein the cylindrical wall of the retention flange includes a plurality of openings and the annular rim of the output spindle includes a plurality of radial projections configured to be fittingly received into the plurality of openings to rotationally fix the retention flange to the output spindle.