Angle grinder

• US 8,087,977 B2
• Filed: 04/24/2006
• Issued: 01/03/2012
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Inventors: Gallagher, William F., Doyle, Michael C., Hatfield, Eric E., Tomayko, David C., Krout, Daniel L., Malloy, Tanika
• Primary Examiner(s): Eley, Timothy V
• Application Number:
  US11/409,904
• Publication Number:
  US 20060276114A1
• Time in Patent Office: 2,080 Days
• Field of Search: 451/11, 451/344, 451/353, 451/355, 451/359, 451/354, 451/357, 451/358, 451/451, 451/456, 451/488, 310/58, 310/62, 310/63, 310/89, 417/423.8, 417/423.14
• US Class Current: 451/359
• CPC Class Codes: B24B 23/022 Spindle-locking devices, e.g. for mounting or removing the tool
• CPC Class Codes: B24B 23/028 Angle tools
• CPC Class Codes: B24B 45/006 Quick mount and release means for disc-like wheels, e.g. on power tools
• CPC Class Codes: B24B 55/102 with rotating tools
• CPC Class Codes: B25B 23/141 Mechanical overload release couplings
• CPC Class Codes: B25B 23/147 specially adapted for electrically operated wrenches or screwdrivers
• CPC Class Codes: B25F 5/001 Gearings, speed selectors, clutches or the like specially adapted for rotary tools
• CPC Class Codes: B25F 5/008 Cooling means
• CPC Class Codes: H01H 9/06 Casing of switch constituted by a handle serving a purpose other than the actuation of the switch, e.g. by the handle of a vacuum cleaner
• CPC Class Codes: H02K 7/145 Hand-held machine tool

Abstract

An angle grinder is provided including a trigger assembly for selectively actuating the angle grinder. A particle separation assembly is provided for the removal of any dust, particle, or artifacts that may have entered into the housing of the angle grinder. A brush biasing system is also provided to ensure proper and efficient operation of the motor of the angle grinder. An overload monitoring system is included to monitor the loading on the motor. A clutch mechanism is also included to prevent overloading on the motor of the angle grinder. A gear wheel lock mechanism is also provided to prevent the wheel spindle from rotating during installation or removal of a grinding wheel on the wheel spindle. An anti-locking flange system is also included to prevent the over-tightening of the flanges and the grinder wheel during the operation of the angle grinder. A gear case labyrinth feature is also provided.

Claims

1. A particle evacuation system for a power tool comprising:

a motor disposed within a housing;

a fan rotatably connected to the motor and driven by the motor;

a baffle disposed in a handle portion of the housing, radially surrounding at least a portion of the fan, and forming a channel in the baffle; and

an exhaust channel formed in the housing having a first end and a second end,

wherein the channel in the baffle is in fluid communication with the first end of the exhaust channel and

wherein the fan generates an air current to expel any particles located within the housing in a direction away from the motor via the channel formed in the baffle and the exhaust channel formed in the housing.

2. The particle evacuation system of claim 1, wherein the baffle is integrally formed with the housing.

3. The particle evacuation system of claim 1, wherein the size of the exhaust channel increases from the first end to the second end.

4. The particle evacuation system of claim 1, wherein the fan has a plurality of blades that are pitched.

5. The particle evacuation system of claim 1, wherein the fan has a plurality of blades that distally decrease in size.

12. The particle evacuation system of claim 1, wherein the fan generates an air current to expel any particles located within the housing via the channel formed in the baffle and the exhaust channel formed in the housing.

6. A power tool comprising:

a housing having a longitudinal axis, a first end and a second end;

a motor disposed in the housing;

a working tool wheel driven by the motor and disposed proximate the first end of the housing;

a first fan disposed in the housing proximate the first end of the housing, the first fan rotatably connected to the motor and driven by the motor, the first fan forcing airflow to move generally linearly along the longitudinal axis;

a second fan disposed in the housing proximate the second end of the housing, the second fan rotatably connected to the motor and driven by the motor, the second fan forcing airflow to rotate about the longitudinal axis, wherein the motor is disposed between the first and second fans;

a baffle disposed in a handle portion of the housing, radially surrounding at least a portion of the second fan, and forming a channel in the baffle; and

an exhaust channel formed proximate the second end of the housing, the exhaust channel having a first end and a second end,

wherein the channel in the baffle is in fluid communication with the first end of the exhaust channel.

7. The power tool of claim 6, wherein the baffle is integrally formed with the housing.

8. The power tool of claim 6, wherein the size of the exhaust channel increases from the first end to the second end.

9. The power tool of claim 6, wherein the fan has a plurality of blades that are pitched.

10. The power tool of claim 6, wherein the fan has a plurality of blades that distally decrease in size.

11. The power tool of claim 6, wherein the second fan generates an air current to expel any particles located within the housing via the channel formed in the baffle and the exhaust channel formed in the housing.

13. An angle grinder comprising:

a housing having a handle portion, 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 wheel spindle operatively connected to the gear set;

a first fan disposed in field case portion of the housing, the first fan rotatably connected to the motor and driven by the motor;

a second fan disposed in the handle portion of the housing, the second fan rotatably connected to the motor and driven by the motor, wherein the motor is disposed between the first and second fans;

a baffle disposed in handle portion of the housing, radially surrounding at least a portion of the second fan, and forming a channel in the baffle; and

an exhaust channel formed in the handle portion of the housing, the exhaust channel having a first end and a second end,

wherein the channel in the baffle is in fluid communication with the first end of the exhaust channel.

14. The angle grinder of claim 13, wherein the baffle is integrally formed with the housing.

15. The angle grinder of claim 13, wherein the size of the exhaust channel increases from the first end to the second end.

16. The angle grinder of claim 13, wherein the fan has a plurality of blades that are pitched.

17. The angle grinder of claim 13, wherein the fan has a plurality of blades that distally decrease in size.

18. The angle grinder of claim 13, wherein the second fan generates an air current to expel any particles located within the housing via the channel formed in the baffle and the exhaust channel formed in the housing.