Brake cartridges for power equipment

• US 7,845,258 B2
• Filed: 03/27/2008
• Issued: 12/07/2010
• Est. Priority Date: 08/20/2003
• Status: Active Grant

• Current Assignee: Sawstop Holding LLC
• Original Assignee: SD3, LLC
• Inventors: Fanning, David A., Gass, Stephen F., Fulmer, J. David
• Primary Examiner(s): Alie; Ghassem
• Application Number:
  US12/079,820
• Publication Number:
  US 20080184857A1
• Time in Patent Office: 985 Days
• Field of Search: 83/621, 83D/IG.1, 834/772, 835/221.2, 835/81, 83/72, 83/767, 834/78, 834/615, 834/73, 834/771, 834/81, 83487-490, 835/74, 838/21, 838/23, 838/27, 838/29, 836/65, 836/66, 839/54, 833/971, 451/451, 451/1, 451/6, 451/9, 451/119, 451/158, 451/177, 307/326, 283/74, 188/73.31, 188/300, 188/367, 188/156, 188/242, 188/DIG.1, 188/73.34, 340/530, 340/590, 340/680, 403/2, 403/28, 144/384, 144/391, 144/427, 144/154, 144/356
• US Class Current: 83/58
• 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: F16D 2127/008 Trigger mechanisms
• CPC Class Codes: F16D 63/00 Brakes not otherwise provided for; Brakes combining more than one of the types of groups F16D49/00 - F16D61/00
• 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 83/7726 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
• CPC Class Codes: Y10T 83/8773 Bevel or miter cut

Abstract

Safety systems for power equipment and components and brake cartridges for use in those safety systems are disclosed. The safety systems, components and brake cartridges are specifically applicable for woodworking equipment such as saws. An exemplary brake cartridge includes a housing and a braking component configured to engage a moving part of the power tool upon occurrence of a predetermined event. The brake cartridge may further include a switch configured so that proper installation of the cartridge in the power tool triggers the switch.

Claims

1. A brake cartridge for use in safety systems for power tools, the cartridge comprising:

a housing;

a system to perform a predetermined action, where at least part of the system is enclosed within the housing;

circuitry enclosed in the housing and adapted to trigger the system;

switch means enclosed in the housing and operably associated with the circuitry for indicating through activation of the switch means that the cartridge is properly installed in a power tool; and

switch contactor means enclosed in the housing for activating the switch means when the cartridge is properly installed in the power tool.

2. A brake cartridge for use in safety systems for power tools, the cartridge comprising:

a housing;

a brake pawl associated with the housing and adapted to pivot relative to the housing;

a spring at least partially enclosed in the housing and adapted to pivot the brake pawl relative to the housing when the spring expands;

a fuse wire adapted to hold the spring in compression;

circuitry enclosed in the housing and adapted to fuse the fuse wire to release the spring;

a plug associated with the housing and adapted to engage a corresponding plug in the power tool;

switch means enclosed in the housing for indicating the cartridge is properly installed when the switch means is activated, where the switch means is configured to be activated through contact; and

switch contactor means enclosed in the housing for contacting and activating the switch means when the cartridge is properly installed in the power tool.

3. The brake cartridge of claim 2, further comprising aperture means for receiving a rotatable key, where rotation of the key causes the switch contactor means to contact and activate the switch means.

4. The brake cartridge of claim 3, where the aperture means is configured to allow the key to rotate to cause the switch contactor means to contact and activate the switch means only when the cartridge is properly installed in the power tool.