COLLET FOR A POWER TOOL

• US 3,811,361 A
• Filed: 11/13/1972
• Issued: 05/21/1974
• Est. Priority Date: 11/13/1972
• Status: Expired due to Term

• Current Assignee: Ryobi Motor Products Incorporated (Techtronic Industries Company Limited)
• Original Assignee: Robert W. Seely, William A. Batson
• Inventors: Seely, Robert W., Batson, William A.
• Primary Examiner(s): Husar, Francis S.
• Application Number:
  US05/306,090
• Time in Patent Office: 554 Days
• Field of Search: 279/1ME,51,52 90/12D 144/134D,136C
• US Class Current: 409/182
• CPC Class Codes: B23B 31/202 Details of the jaws
• CPC Class Codes: Y10T 279/17538 Threaded-sleeve actuator
• CPC Class Codes: Y10T 409/306608 End mill [e.g., router, etc.]

Abstract

A collet for a power tool such as a router which has a lockable armature shaft, the lower end of which is externally threaded and internally bored so that it may be fitted with an interconnected nut and split sleeve combination. The split sleeve fits within the internal bore of the shaft whereby on turning of the nut in one direction the sleeve will be compressed to lock the shank of a bit within its central aperture. To remove the bit the nut is turned in the opposite direction to jack the sleeve away from the shaft.

Claims

1. In a motor driven router having a housing and a base, the combination of:

a. an armature shaft journaled in the housing with the free end thereof extending toward the base and adapted to rotate a bit, b. a locking means connected to the housing detachably to engage the armature shaft to prevent rotation thereof, c. the free end of the armature shaft being externally threaded and internally bored, d. the internal bore of the free end frustoconical in shape to flare outwardly to the bottom of the end, e. a nut threadedly connected to the external thread of the free end of the armature shaft, f. an inwardly extending radial flange formed on the nut, g. a split sleeve having a frustoconical section corresponding to the taper of the internal bore, an axially extending neck section having an axial length of substantially twice the axial length of the flange, the neck section having an upper end and a lower end, the neck section having a diameter slightly smaller than the diameter of the radial flange of the nut to permit relative axial sliding movement therebetween, and a shoulder extending radially outwardly from the upper end of the neck section to terminate at the lower end of the conical section, h. an annular groove formed on and inwardly of the lower end of the neck section of the sleeve remote from the shoulder, and at an axial distance from the shoulder of approximately one and one-half times the axial length of the flange, i. the sleeve received within the nut with the neck section extending axially below the flange and the shoulder seated upon the flange, j. a retaining clip disposed in the annular groove to define a second annular groove to captively locate the flange between the shoulder and the clip, said second annular groove having an axial extent equal to approximately one and one-half times the axial length of the flange thereby providing an axial clearance for the flange within the second annular groove of approximately one-half the length of said flange, k. the nut threadedly received on the externally threaded lower end of the armature shaft to place the conical section of the sleeve within the internal bore of the free end of the armature shaft, l. the nut to be turned in one direction to have the flange engage the shoulder and force the sleeve into the internal bore to compress the split of the sleeve and clamp the same securely therein, and m. the nut to be turned in the opposite direction to move the flange axially downwardly through an axial distance equal to the axial clearance to engage the clip, and jack the sleevE from the shaft whereby the respective conical sections will separate and the shoulders of the sleeve will come to rest upon the flange with the split in uncompressed position.