Keyless chuck assembly

Patent metadata

Field	Value
Publication number	US-10946455-B2
Application number	US-201916530318-A
Country	US
Kind code	B2
Filing date	Aug 2, 2019
Priority date	Aug 3, 2018
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

A keyless chuck for attaching a tool bit to a power tool includes a knob having a central aperture and defining a longitudinal axis, a hub within the central aperture and configured to attach to the power tool, and a collet within the hub and having a receiving end configured to receive the tool bit. The knob is adjustable between a locked position in which a clamping force is applied to the collet to retain the tool bit therein, and an unlocked position in which the clamping force is relieved to permit removal of the tool bit.

First claim

What is claimed is:

1. A keyless chuck for attaching a tool bit to a power tool, the power tool including a spindle having a tapered internal bore, the keyless chuck comprising:
a knob having a central aperture and defining a longitudinal axis;
a hub within the central aperture and configured to attach to the power tool, the hub having a threaded bore;
a collet within the hub and having a receiving end configured to receive the tool bit; and
a coil spring that resides within the threaded bore for biasing the collet outward from the tapered internal bore;
wherein the knob is adjustable between a locked position in which a clamping force is applied to the collet to retain the tool bit therein, and an unlocked position in which the clamping force is relieved to permit removal of the tool bit;
wherein the collet is received by the tapered internal bore, and wherein the collet advances into the tapered internal bore when the keyless chuck is adjusted from the unlocked position to the locked position.

2. The keyless chuck of claim 1 , wherein the hub is configured to attach to the spindle.

3. The keyless chuck of claim 1 , wherein the knob is adjustable between the locked position and the unlocked position by rotation of the knob relative to the hub about the longitudinal axis.

4. The keyless chuck of claim 3 , wherein one of the knob and the hub includes a circumferential slot extending about a circumference thereof, wherein at least a portion of the circumferential slot is obliquely oriented relative to the longitudinal axis, and wherein the keyless chuck further comprises a ball bearing that protrudes partially into the slot.

5. The keyless chuck of claim 4 , wherein the other of the knob and the hub includes an indentation, and the ball bearing is partially contained within the indentation.

6. The keyless chuck of claim 5 , wherein the circumferential slot includes a first end and a second end, and the ball bearing traverses the slot between the first and second ends when the knob is rotated relative to the hub about the longitudinal axis.

7. The keyless chuck of claim 6 , further comprising a disk spring within the knob for applying an axial preload force to the collet in response to adjustment of the knob from the unlocked position to the locked position.

8. The keyless chuck of claim 7 , wherein the knob, when adjusted from the locked position to the unlocked position, permits the disk spring to rebound and relieve the axial preload force on the collet, and thus the clamping force, to permit removal of the tool bit.

9. The keyless chuck of claim 7 , wherein the knob includes a lower counterbore, and wherein the keyless chuck further comprises a lower washer supported within the lower counterbore beneath the disk spring.

10. The keyless chuck of claim 9 , further comprising a captured washer fitted to the collet adjacent the receiving end, wherein the disk spring is positioned between the captured washer and the lower washer.

11. The keyless chuck of claim 1 , wherein the keyless chuck is configured to be adjusted between the unlocked position and the locked position without the use of tools.

12. A router configured to attach to a tool bit, the router comprising:
a motor unit including a spindle having a tapered internal bore;
a keyless chuck for attaching the tool bit to the spindle, the keyless chuck including
a knob having a central aperture and defining a longitudinal axis;
a hub within the central aperture and configured to attach to the spindle;
a collet within the hub and received by the tapered internal bore and having a receiving end configured to receive the tool bit; and
a disk spring within the knob;

wherein the knob is adjustable between a locked position in which a clamping force is applied to the collet to retain the tool bit therein, and an unlocked position in which the clamping force is relieved to permit removal of the tool bit;
wherein the collet advances into the tapered internal bore when the keyless chuck is adjusted from the unlocked position to the locked position; and
wherein the disk spring applies an axial preload force to the collet in response to adjustment of the knob from the unlocked position to the locked position.

13. The router of claim 12 , wherein the knob is adjustable between the locked position and the unlocked position by rotation of the knob relative to the hub about the longitudinal axis.

14. The router of claim 13 , wherein the knob includes a circumferential exterior surface configured to be gripped by a user to apply torque to the knob to adjust the knob between the locked position and the unlocked position.

15. The router of claim 14 , wherein the circumferential exterior surface includes a texture configured to enhance a grip of the user.

16. The router of claim 12 , wherein one of the knob and the hub includes a circumferential slot extending about a circumference thereof, wherein the keyless chuck further comprises a ball bearing that protrudes partially into the slot, wherein the circumferential slot includes a first end and a second end, and wherein the ball bearing traverses the slot between the first and second ends when the knob is rotated relative to the hub about the longitudinal axis.

17. A keyless chuck for attaching a tool bit to a power tool, the power tool including a spindle having a tapered internal bore, the keyless chuck comprising:
a knob having a central aperture and defining a longitudinal axis;
a hub within the central aperture and configured to attach to the power tool;
a collet within the hub and having a receiving end configured to receive the tool bit; and
a disk spring within the knob;
wherein the knob is adjustable between a locked position in which a clamping force is applied to the collet to retain the tool bit therein, and an unlocked position in which the clamping force is relieved to permit removal of the tool bit, and wherein the disk spring applies an axial preload force to the collet in response to adjustment of the knob from the unlocked position to the locked position.

Assignees

• Milwaukee Electric Tool Corp

Inventors

• Sigafoose Tyler S

Classifications

• B23B31/20125 Primary

  Axially fixed cam, moving jaws · CPC title

• Y10T279/17538

  Threaded-sleeve actuator · CPC title

• Y10T409/309408

  with cutter holder · CPC title

• B27C5/10

  Portable hand-operated wood-milling machines; Routers · CPC title

• B23B2260/106

  Nuts · CPC title