Particle separation assembly for power tool

Patent metadata

Field	Value
Publication number	US-9821433-B2
Application number	US-201514717168-A
Country	US
Kind code	B2
Filing date	May 20, 2015
Priority date	May 20, 2014
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

A power tool is provided including a having a field case portion and a gear case portion, a motor disposed in the field case portion of the housing, a fan rotatably connected to the motor, intake conduits disposed along the housing, and a particle separation assembly in fluid communication with the intake conduits. The particle separation assembly includes a baffle and a centrifugal chamber, where the baffle is operable to direct airflow from the intake conduits into the centrifugal chamber in a cyclonic path, and the centrifugal chamber includes a radial gap forming a particle dispersion port in the cyclonic path of the airflow to eject contamination from the airflow. Additionally or alternatively, the centrifugal chamber includes air-directing fins arranged angularly to direct contamination from the airflow towards the particle dispersion port.

First claim

The invention claimed is:

1. A power tool comprising:
a housing including a field case portion and a gear case portion;
a motor disposed in the field case portion of the housing, the motor having a longitudinal axis;
a gear set disposed in the gear case portion of the housing and operatively connected to the motor via a motor spindle;
a fan rotatably connected to the motor;
a plurality of intake conduits disposed along the housing; and
a particle separation assembly in fluid communication with the plurality of intake conduits and including a baffle and a centrifugal chamber, wherein the baffle includes a plane being substantially perpendicular to the longitudinal axis of the motor, the baffle comprising a plurality of blades that extend angularly with respect to the plane of the baffle and are operable to direct airflow from the intake conduits into the centrifugal chamber in a cyclonic path, and wherein the centrifugal chamber is defined by an inner surface, the inner surface following a substantially spiral path outwardly about the longitudinal axis from an inner edge to an outer edge that is radially offset from the inner edge to form a particle dispersion port in the cyclonic path of the airflow, wherein contamination is substantially separated from the airflow within the centrifugal chamber and ejected from the centrifugal chamber through the particle dispersion port.

2. The power tool of claim 1 , wherein the particle separation assembly includes an end cap.

3. The power tool of claim 2 , wherein the end cap includes an inner surface having a substantially semi-spherical, semi-spherical with a frustum flat portion, or frusto-conical shape around the centrifugal chamber.

4. The power tool of claim 3 , wherein the inner surface of the end cap includes a spiral portion having a radius that gradually increases to form the particle dispersion port.

5. The power tool of claim 2 , further comprising a handle portion disposed between the field case portion and the particle separation assembly.

6. The power tool of claim 5 , wherein the end cap comprises an inwardly-projecting post projecting through the baffle to mate with the handle portion.

7. The power tool of claim 5 , wherein the handle portion comprises a plurality of spaced-apart fins arranged circumferentially around an end of the handle portion.

8. The power tool of claim 7 , wherein the end of the handle portion includes a sloped surface forming the plurality of intake conduits between the plurality of spaced-apart fins, and the baffle comprises an outer ring mounted on an end of the plurality of spaced-apart fins to receive the airflow through the plurality of intake conduits.

9. The power tool of claim 2 , wherein the end cap comprises a plurality of air-directing fins on an inner surface thereof disposed angularly with respect to a center of the end cap to direct particles from the airflow towards an outer periphery of the centrifugal chamber.

10. The power tool of claim 1 , wherein the particle separation assembly does not include a passive fan or a separate active fan different from the fan.

11. A power tool comprising:
a housing including a field case portion and a gear case portion;
a motor disposed in the field case portion of the housing;
a gear set disposed in the gear case portion of the housing and operatively connected to the motor via a motor spindle;
a fan rotatably connected to the motor;
a plurality of intake conduits disposed along the housing; and
a particle separation assembly in fluid communication with the plurality of intake conduits and including a baffle and an end cap forming a centrifugal chamber, wherein the baffle includes a plurality of angular blades operable to direct airflow from the intake conduits into the centrifugal chamber in a cyclonic path, and an inner surface of the end cap includes a particle dispersion port at or near a periphery of the centrifugal chamber and at least one air-directing fin arranged angularly with respect to a center of the end cap to direct contamination from the airflow towards the particle dispersion port.

12. The power tool of claim 11 , wherein the inner surface of the end cap includes a substantially semi-spherical, semi-spherical with a frustum flat portion, or frusto-conical shape around the centrifugal chamber.

13. The power tool of claim 11 , wherein the inner surface of the end cap includes a spiral portion having a radius that gradually increases to form a radial gap for the particle dispersion port.

14. The power tool of claim 11 , further comprising a handle portion disposed between the field case portion and the particle separation assembly.

15. The power tool of claim 14 , wherein the end cap comprises an inwardly-projecting post projecting through the baffle to mate with the handle portion.

16. The power tool of claim 14 , wherein the handle portion comprises a plurality of spaced-apart fins arranged circumferentially around an end of the handle portion.

17. The power tool of claim 16 , wherein the end of the handle portion includes a sloped surface forming the plurality of intake conduits between the plurality of spaced-apart fins, and the baffle comprises an outer ring mounted on an end of the plurality of spaced-apart fins to receive the airflow through the plurality of intake conduits.

18. The power tool of claim 11 , wherein the particle separation assembly does not include a passive fan or a separate active fan different from the fan.

19. The power tool of claim 11 , wherein the power tool is a grinder having a handle girth of less than approximately 25 cm.

20. A power tool comprising:
a housing including a field case portion and a gear case portion;
a motor disposed in the field case portion of the housing, the motor having a longitudinal axis;
a gear set disposed in the gear case portion of the housing and operatively connected to the motor via a motor spindle;
a fan rotatably connected to the motor;
a plurality of intake conduits disposed along the housing; and
a particle separation assembly in fluid communication with the plurality of intake conduits and including a baffle having a plane extending radially from the longitudinal axis of the motor, and an end cap having a substantially semi-spherical inner surface forming a centrifugal chamber and a particle dispersion port disposed on a peripheral portion of the centrifugal chamber, wherein the baffle includes a plurality of blades that extend angularly with respect to the plane of the baffle and are operable to direct airflow from the intake conduits into the centrifugal chamber in a cyclonic path to dispense contamination from the airflow through the particle dispersion port, and wherein an inner surface of the end cap includes a spiral portion having a radius that gradually increases from an inner point to an outer point that is disposed farther from an axial center of the end cap than the inner point, the particle dispersion port being formed as a radial gap between the inner point and the outer point.

Assignees

• Black & Decker Inc

Inventors

• Copeland Earnest N
• Cirincione Ii Robert J

Classifications

• B25F5/008

  Cooling means · CPC title

• B24B41/007

  Weight compensation; Temperature compensation; Vibration damping · CPC title

• B24B23/028

  Angle tools · CPC title

• B01D45/16

  generated by the winding course of the gas stream {, the centrifugal forces being generated solely or partly by mechanical means, e.g. fixed swirl vanes} · CPC title

• B24B55/102 Primary

  with rotating tools · CPC title