Accessory clamp and spindle lock mechanism for power tool

Patent metadata

Field	Value
Publication number	US-10682736-B2
Application number	US-201715718609-A
Country	US
Kind code	B2
Filing date	Sep 28, 2017
Priority date	Sep 29, 2016
Publication date	Jun 16, 2020
Grant date	Jun 16, 2020

Abstract

A power tool is provided including a motor driving a shaft and a drive spindle. The drive spindle includes an outer spindle rotatably driven by the shaft and an inner spindle disposed within the outer spindle. The outer spindle includes an end portion defining an engagement surface for mounting a working accessory, and the inner spindle is axially moveable along a longitudinal axis of the outer spindle but rotationally fixed to the outer spindle. A spring member is arranged to apply a biasing force on the inner spindle in a first direction with respect to the outer spindle. Securing the working accessory on the drive spindle against the engagement surface of the outer spindle applies an axial force on the inner spindle in a second direction opposite the first direction with respect to the outer spindle.

First claim

The invention claimed is:

1. A power tool comprising:
a motor driving a shaft;
a drive spindle including an outer spindle rotatably driven by the shaft and an inner spindle disposed within the outer spindle, the outer spindle having an end portion defining an engagement surface for mounting a working accessory, the inner spindle being axially moveable along a longitudinal axis of the outer spindle but rotationally fixed to the outer spindle; and
a spring member arranged to apply a biasing force on the inner spindle in a first direction with respect to the outer spindle,
wherein the inner spindle includes a lower portion extending out of the end portion of the outer spindle and arranged to be received through an opening of the working accessory, the lower portion of the inner spindle including a threaded portion on an outer surface thereof, the lower portion of the inner spindle being receivable through the opening of the working accessory in a direction from an upper surface of the working accessory towards a lower surface thereof as the upper surface of the working accessory moves into contact with the engagement surface of the outer spindle, the threaded portion of the inner spindle being fastened either directly to a threaded portion of the opening of the working accessory or to a threaded nut provided in contact with the lower surface of the working accessory to secure the working accessory on the drive spindle, and
wherein securing the working accessory on the drive spindle against the engagement surface of the outer spindle applies an axial force on the inner spindle in a second direction opposite the first direction with respect to the outer spindle.

2. The power tool of claim 1 , wherein the outer spindle comprises an inner collar on an inner surface thereof, and the inner spindle comprises a top portion arranged to engage the inner collar.

3. The power tool of claim 2 , wherein the spring member is arranged to engage the inner collar opposite the top portion of the inner spindle.

4. The power tool of claim 3 , further comprising a shoulder bolt member having a head portion engaging the spring member opposite the inner collar, and a lower portion secured to the top portion of the inner spindle through the inner collar.

5. The power tool of claim 4 , wherein the lower portion of the shoulder bolt member is threaded and the top portion of the inner spindle includes a corresponding threaded opening into which the lower portion of the shoulder bolt member is fastened.

6. The power tool of claim 4 , further comprising a depressor arranged to engage the head portion of the shoulder bolt member opposite the spring member, wherein a depression of the depressor applies an axial force to the inner spindle in the second direction with respect to the outer spindle.

7. The power tool of claim 6 , further comprising a gear case supporting the depressor, and a spring applying a biasing force to the depressor in the first direction with respect to the gear case.

8. The power tool of claim 6 , further comprising an actuation mechanism arranged to engage an upper portion of the depressor to apply an axial force on the depressor in the second direction, the actuation mechanism comprising a pivot member, a cam member pivotably attached to the pivot member, and a handle that pivots the cam member around the pivot member to apply the axial force on the depressor in the second direction.

9. A power tool comprising:
a motor driving a shaft;
a drive spindle including an outer spindle rotatably driven by the shaft and an inner spindle disposed within the outer spindle, the outer spindle having an end portion defining an engagement surface for mounting a working accessory, the inner spindle including a first end arranged to be received through an opening of the working accessory and a second end;
a depressor having a first end and a second end, the first end extending into the outer spindle to selectively engage the second end of the inner spindle within the outer spindle; and
an actuation mechanism arranged to apply force on the second end of the depressor to axially move the first end of the depressor into selective engagement with the second end of the inner spindle,
wherein the first end of the depressor and the second end of the inner spindle include corresponding uneven surfaces engageable to rotationally lock the inner spindle, and thereby the outer spindle, when the depressor is axially moved into engagement with the second end of the inner spindle.

10. The power tool of claim 9 , wherein the actuation mechanism comprises a pivot member, a cam member pivotably attached to the pivot member, and a handle that pivots the cam member around the pivot member to apply force on the depressor towards the drive spindle.

11. The power tool of claim 9 , further comprising a gear case supporting the depressor, and a spring applying a biasing force to the depressor with respect to the gear case away from the drive spindle.

12. The power tool of claim 11 , wherein the gear case comprises an annular collar disposed around the depressor, the first end of the depressor being disposed between the drive spindle and a first surface of the collar, and the spring engaging a second surface of the collar and the second end of the depressor.

13. The power tool of claim 12 , further comprising a rotation arrestor attached around the second end of the depressor to keep the depressor from rotating with respect to the gear case, the spring being disposed around the depressor between the second surface of the collar and the rotation arrestor.

14. The power tool of claim 9 , wherein the drive spindle comprises an outer spindle rotatably driven by the shaft, and an inner spindle disposed within the outer spindle, the inner spindle being axially moveable along a longitudinal axis of the outer spindle but rotationally fixed to the outer spindle.

15. The power tool of claim 9 , wherein the first end of the depressor and the second end of the drive spindle have correspondingly uneven mating surfaces.

Assignees

• Black & Decker Inc

Inventors

• Christophersen Kyle J
• Copeland Jr Earnest N

Classifications

• B24B23/022 Primary

  Spindle-locking devices, e.g. for mounting or removing the tool · CPC title

• B24B45/00

  Means for securing grinding wheels on rotary arbors (suppression of vibrations in systems F16F15/00; testing static or dynamic balancing of machines G01M1/00) · CPC title

• B23Q3/12

  for securing to a spindle in general (B23Q3/152 takes precedence; chucks B23B31/02) · CPC title

• B24B23/028

  Angle tools · CPC title

• B24B55/00

  Safety devices for grinding or polishing machines; Accessories fitted to grinding or polishing machines for keeping tools or parts of the machine in good working condition (of general applicability for machine tools B23Q11/00; in general F16P) · CPC title