Replaceable brake mechanism for power equipment

• US 20020020261A1
• Filed: 08/13/2001
• Published: 02/21/2002
• Est. Priority Date: 08/14/2000
• Status: Active Grant

• Current Assignee: Sawstop Holding LLC
• Original Assignee: SD3, LLC
• Inventors: McDonald, Anwyl M., Jensen, Joel F., Gass, Stephen F., Johnston, Andrew L., Kim, Sung H., DʼAscenzo, David S.
• Granted Patent: US 7,610,836 B2
• Time in Patent Office: Days
• 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 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 19/00 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: 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 83/613 Work guard
• CPC Class Codes: Y10T 83/7693 Tool moved relative to work-support during cutting
• CPC Class Codes: Y10T 83/7697 Tool angularly adjustable relative to work-support
• CPC Class Codes: Y10T 83/773 Work-support includes passageway for tool [e.g., slotted table]
• CPC Class Codes: Y10T 83/7734 With guard for tool
• CPC Class Codes: Y10T 83/7788 Tool carrier oscillated or rotated
• CPC Class Codes: Y10T 83/8773 Bevel or miter cut

Abstract

Woodworking machines are disclosed having cutting tools adapted to cut workpieces. The machines include a safety system adapted to detect one or more dangerous conditions between a person and the cutting tool, and to stop movement of the cutting tool upon detection of the dangerous condition. At least part of the safety system is housed in a removable cartridge.

Claims

1. A woodworking machine comprising:

a support frame including a work surface for supporting workpieces;

a cutting tool supported by the frame and movable relative to the work surface to cut the workpieces supported by the work surface; and

a safety brake system configured to detect a dangerous condition between a person and the cutting tool, and to stop movement of the cutting tool upon detection of the dangerous condition;

where the safety brake system includes one or more single-use components mounted in a cartridge removably coupled to the support frame.

2. The machine of claim 1, where the cartridge is sealed against entry of sawdust.

3. The machine of claim 1, where the one or more single-use components includes a fusible member.

4. The machine of claim 3, where the safety brake system includes a firing system adapted to melt the fusible member, and where the firing system is mounted in the cartridge.

5. The machine of claim 4, where the firing system includes a capacitor.

6. The machine of claim 1, where the safety brake system includes a brake pawl selectively movable to engage the cutting tool upon detection of the dangerous condition, and where the brake paw l is mounted in the cartridge.

7. The machine of claim 6, where the safety brake system includes a spring mounted in the cartridge and arranged to urge the brake pawl into contact with the cutting tool.

8. The machine of claim 7, where the safety brake system includes a fusible member mounted in the cartridge and arranged to hold the brake pawl spaced-apart from the cutting tool until the dangerous condition is detected.

9. The machine of claim 8, where the safety brake system includes at least one capacitor configured to store electrical charge to melt the fusible member upon detection of the dangerous condition, and where the capacitor is mounted in the cartridge.

10. The machine of claim 1, further comprising at least one motor configured to drive the cutting tool, and a control system configured to determine if at least one of the single-use components mounted in the cartridge has been used, and where the control system is configured to prevent operation of the at least one motor if one of the single-use components has been used.

11. The machine of claim 1, where the cartridge includes key structure, and where the support frame includes corresponding key structure configured to engage the cartridge key structure to prevent incorrect installation of the cartridge.

13. The machine of claim 12, where the cartridge includes at least one opening sealed by a plastic film.

14. The machine of claim 12, where the cartridge includes at least one opening sealed by a metal film.

15. The machine of claim 12, where the brake system includes at least one brake pawl mounted in the cartridge, and where the brake pawl is selectively movable into contact with the cutting tool upon detection of the dangerous condition.

16. The machine of claim 12, where the brake system includes at least one brake pawl and an actuator configured to move the brake pawl into contact with the cutting tool, and where the actuator is mounted in the cartridge.

18. The machine of claim 17, where the brake positioning system allows the cartridge to be adjusted to accommodate different sized cutters.

19. The machine of claim 17, where the brake positioning system includes a pivot on which the cartridge is mounted, and where the position of the brake cartridge relative to the cutter is adjusted by rotating the cartridge on the pivot.

12. A woodworking machine comprising:

a cutting tool adapted to cut a workpiece;

a motor adapted to drive the cutting tool;

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

a brake system adapted to stop the cutting tool upon detection of the dangerous condition, where at least part of the brake system is housed in a cartridge and the cartridge is sealed against entry of sawdust.

17. A woodworking machine, comprising:

a support frame;

a cutter supported by the support frame;

a brake cartridge mountable on the support frame and including a brake pawl adapted to selectively engage and stop the cutter; and

a brake positioning system associated with the support frame and adapted to receive and operably position the brake cartridge relative to the cutter.