Power equipment with systems to mitigate or prevent injury

• US 8,011,279 B2
• Filed: 12/17/2007
• Issued: 09/06/2011
• Est. Priority Date: 08/14/2000
• Status: Expired due to Fees

• Current Assignee: Sawstop Holding LLC
• Original Assignee: SD3, LLC
• Inventors: D'Ascenzo, David S., Gass, Stephen F.
• Primary Examiner(s): Alie; Ghassem
• Application Number:
  US12/002,388
• Publication Number:
  US 20080092702A1
• Time in Patent Office: 1,359 Days
• Field of Search: 83/58, 83/59, 83/621, 83D/IG.1, 835/81, 833/971, 834/771, 835/772, 834/71, 144/3.1
• US Class Current: 83/58
• CPC Class Codes: B23D 59/001 Measuring or control devices, e.g. for automatic control of work feed pressure on band saw blade measuring in general G01; controlling in general G05
• CPC Class Codes: B27B 13/14 Braking devices specially designed for band sawing machines, e.g. acting after damage of the band saw blade
• CPC Class Codes: B27B 5/38 Devices for braking the circular saw blade or the saw spindle; Devices for damping vibrations of the circular saw blade, e.g. silencing B23D47/005 takes precedence
• CPC Class Codes: B27G 19/00 Safety guards or devices specially adapted for wood saws; Auxiliary devices facilitating proper operation of wood saws
• CPC Class Codes: B27G 19/02 for circular saws
• CPC Class Codes: F16P 3/12 with means, e.g. feelers, which in case of the presence of a body part of a person in or near the danger zone influence the control or operation of the machine F16P3/08 takes precedence
• CPC Class Codes: F16P 3/148 using capacitive technology
• CPC Class Codes: Y10T 83/04 Processes
• CPC Class Codes: Y10T 83/081 With randomly actuated stopping means
• CPC Class Codes: Y10T 83/083 With means to permit subsequent hand operation
• CPC Class Codes: Y10T 83/089 Responsive to tool characteristic
• CPC Class Codes: Y10T 83/536 Movement of work controlled
• CPC Class Codes: Y10T 83/613 Work guard
• CPC Class Codes: Y10T 83/7684 With means to support work relative to tool[s]
• CPC Class Codes: Y10T 83/7726 By movement of the tool
• CPC Class Codes: Y10T 83/773 Work-support includes passageway for tool [e.g., slotted table]
• CPC Class Codes: Y10T 83/8773 Bevel or miter cut

Abstract

Woodworking machines are disclosed having cutting tools for cutting workpieces. The machines include a detection system adapted to detect one or more dangerous conditions between a person and the cutting tool. The machines also include a mechanism having a moveable component adapted to move upon detection of the dangerous condition by the detection system. Movement of the moveable component contributes to one or more of the following actions to mitigate or prevent injury to the person: deceleration of the cutting tool, retraction of the cutting tool, and placement of a barrier over at least a part of the cutting tool. An actuator is adapted to move the moveable component at a high acceleration when the dangerous condition is detected.

Claims

1. A woodworking machine comprising:

a support frame;

a motor supported by the frame;

a cutting tool supported by the frame and moveable by the motor;

a detection system adapted to detect a dangerous condition between a person and the cutting tool;

a mechanism having a moveable component adapted to move upon detection of the dangerous condition by the detection system, where movement of the moveable component contributes to one or more of the following actions to mitigate or prevent injury to the person;

deceleration of the cutting tool, and retraction of the cutting tool; and

an actuator having stored energy sufficient to move the moveable component 1/32^nd of an inch within approximately 3 milliseconds or less after the dangerous condition is detected.

2. The machine of claim 1, where the actuator includes one or more springs.

3. The machine of claim 2, where the one or more springs are adapted to apply at least 50 lbs. of force to move the moveable component.

4. The machine of claim 2, where the one or more springs are adapted to apply at least 100 lbs. of force to move the moveable component.

5. The machine of claim 1, where the actuator is adapted to move the moveable component at an acceleration of over 500 ft/s² when the detection system detects the dangerous condition.

6. The machine of claim 1, where the actuator is adapted to move the moveable component at an acceleration of over 2000 ft/s² when the detection system detects the dangerous condition.

7. The machine of claim 1, where the movement of the moveable component contributes to the deceleration of the cutting tool.

8. The machine of claim 7, where the moveable component is a brake.

9. The machine of claim 1, where the movement of the moveable component contributes to deceleration of the cutting tool and to retraction of the cutting tool.

10. The machine of claim 1, where the support frame includes a table and the cutting tool comprises a blade adapted to extend at least partially above the table.

11. The machine of claim 10, where the movement of the moveable component contributes to the retraction of the cutting tool at least partially below the table.

12. The machine of claim 1, where the support frame includes a table and a housing, and where the moveable component is within the housing.

13. A woodworking machine comprising:

a support frame;

a motor supported by the frame;

a cutting tool supported by the frame and moveable by the motor;

a detection system adapted to detect a dangerous condition between a person and the cutting tool;

a mechanism having a moveable component adapted to move upon detection of the dangerous condition by the detection system, where movement of the moveable component contributes to the mitigation or prevention of injury to the person; and

an actuator having stored energy sufficient to move the moveable component 1/32^nd of an inch within approximately 3 milliseconds or less after the dangerous condition is detected at an acceleration of 500 ft/sec² or more.

14. The machine of claim 13, where the actuator is adapted to move the moveable component at an acceleration of approximately 2000 ft/s².

15. The machine of claim 13, where movement of the moveable component contributes to deceleration of the cutting tool.

16. A woodworking machine comprising:

a support frame;

a motor supported by the frame;

a cutting tool supported by the frame and moveable by the motor;

a detection system adapted to detect a dangerous condition between a person and the cutting tool;

a mechanism having a moveable component adapted to move upon detection of the dangerous condition by the detection system, where movement of the moveable component contributes to the mitigation or prevention of injury to the person through retraction of the cutting tool; and

an actuator having stored energy sufficient to move the moveable component 1/32^nd of an inch within approximately 3 milliseconds or less after the dangerous condition is detected.

17. The machine of claim 16, where the actuator is configured to move the moveable component at an acceleration of 500 ft/sec² or more.

18. The machine of claim 16, where the cutting tool is a circular blade and where the mechanism comprises brake means for decelerating the circular blade.