Safety system for power equipment

• US 20060225551A1
• Filed: 06/05/2006
• Published: 10/12/2006
• Est. Priority Date: 10/01/1999
• Status: Abandoned Application

• Current Assignee: SD3, LLC
• Original Assignee: SD3, LLC
• Inventors: Gass, Stephen F.
• Application Number:
  US11/447,449
• Publication Number:
  US 20060225551A1
• Time in Patent Office: Days
• US Class Current: 83/76.800
• 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 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 vibration-damping of sawing machines or devices working with circular saw blades B23D47/005
• 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: H01H 27/00 Switches operated by a removable member, e.g. key, plug or plate; Switches operated by setting members according to a single predetermined combination out of several possible settings combined with plug-and-socket connectors H01R13/70; with current-carrying plug H01R31/08
• CPC Class Codes: H01H 3/022 Emergency operating parts, e.g. for stop-switch in dangerous conditions
• CPC Class Codes: H01H 9/161 comprising light emitting elements
• CPC Class Codes: Y10S 83/01 Safety devices
• CPC Class Codes: Y10T 83/081 With randomly actuated stopping means
• CPC Class Codes: Y10T 83/089 Responsive to tool characteristic
• CPC Class Codes: Y10T 83/175 With condition sensor
• CPC Class Codes: Y10T 83/178 Responsive to work
• 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 83/7788 Tool carrier oscillated or rotated

Abstract

Safety systems for power equipment are disclosed. The safety systems include a detection system adapted to detect contact between a person and a working portion of a machine, where the detection system is adapted to capacitively impart an electric charge on the working portion and to detect when that charge drops; and a reaction system associated with the detection system to cause a predetermined action to take place relative to the working portion upon detection of contact between the person and the working portion by the detection system. Machines equipped with safety systems are also disclosed, such as saws, jointers, etc. The machines include a working portion, such as a cutter or blade, a detection system adapted to detect a dangerous condition between a person and the working portion, and a reaction system associated with the detection system to cause a predetermined action to take place upon detection of the dangerous condition, such as a brake system to stop the working portion, a retraction system to retract the working portion, or a system to cover the working portion. The machines may include a control system adapted to control the operability of one or more of the working portion, the detection system and the reaction system.

Claims

1. A table saw comprising:

a table;

a circular blade adapted to spin and to extend at least partially above the table to cut a work piece on the table;

a detection system capable of detecting contact or dangerous proximity between a person and the blade when the blade is spinning; and

a reaction system adapted to perform some action upon detection of such contact or dangerous proximity with sufficient speed so that the person is cut no deeper than ⅛

^th of an inch when contacting or approaching the blade at any point above the table at a rate of one foot per second.

2. The table saw of claim 1, where the reaction system includes a brake adapted to stop the blade when the detection system detects contact or dangerous proximity.

3. The table saw of claim 1, where the reaction system includes a retraction system adapted to retract the blade when the detection system detects contact or dangerous proximity.

4. The table saw of claim 1, where the reaction system includes a retraction system adapted to move the blade away from the person when the detection system detects contact or dangerous proximity.

5. The table saw of claim 1, where the reaction system is adapted to stop and retract the blade when the detection system detects contact or dangerous proximity.

6. A table saw comprising:

a table;

a circular blade adapted to spin and to extend at least partially above the table to cut a work piece on the table;

detection means for detecting contact or dangerous proximity between a person and the blade when the blade is spinning; and

reaction means for performing some action upon detection of such contact or dangerous proximity with sufficient speed so that the person is cut no deeper than ⅛

^th of an inch when contacting or approaching the blade at any point above the table at a rate of one foot per second.

7. The table saw of claim 6, where the reaction means stops the blade when the detection means detects contact or dangerous proximity.

8. The table saw of claim 6, where the reaction means retracts the blade when the detection means detects contact or dangerous proximity.

9. The table saw of claim 6, where the reaction means moves the blade away from the person when the detection means detects contact or dangerous proximity.

10. The table saw of claim 6, where the reaction means stops and retracts the blade when the detection means detects contact or dangerous proximity.

11. A method of operating a table saw, where the table saw includes a table, a circular blade adapted to spin and to extend at least partially above the table to cut a work piece on the table, a detection system capable of detecting contact or dangerous proximity between a person and the blade when the blade is spinning, and a reaction system adapted to perform some action upon detection of such contact or dangerous proximity with sufficient speed so that the person is cut no deeper than ⅛

^th of an inch when contacting or approaching the blade at any point above the table at a rate of one foot per second, the method comprising;

spinning the blade,

detecting contact or dangerous proximity between the person and the blade, and

if contact or dangerous proximity between the person and the blade is detected, then triggering the reaction system to perform an action with sufficient speed so that the person is cut no deeper than ⅛

^th of an inch when contacting or approaching the blade at any point above the table at a rate of one foot per second.

12. The table saw of claim 11, where the action performed by the reaction system is to stop the blade.

13. The table saw of claim 11, where the action performed by the reaction system is to retract the blade.

14. The table saw of claim 11, where the action performed by the reaction system is to move the blade away from the person.

15. The table saw of claim 11, where the action performed by the reaction system is to stop and retract the blade