Table saw riving knife mounting arrangement

Patent metadata

Field	Value
Publication number	US-10046476-B2
Application number	US-201514848434-A
Country	US
Kind code	B2
Filing date	Sep 9, 2015
Priority date	Sep 9, 2014
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

A riving knife mounting assembly rigidly and accurately positions the riving knife relative to the cutting blade by way of a simple and intuitive mechanism. Interaction between a clamping plate and a locking plate engage opposite sides of the riving knife to hold the riving knife in place, and provides a sensible indication that the two components are properly mated. A cam lever assembly allows loosening or tightening the clamping plate and locking plate together about the riving knife by simply rotation of the lever. A spring assembly maintains pressure on the riving knife even in the loosened position to maintain proper positioning of the components. The clamping plate is part of a mounting bracket that is mounted to a motor arm movable with the drive assembly, and includes adjustment screws for adjusting the orientation of the riving knife relative to the cutting blade in multiple degrees of freedom.

First claim

What is claimed is:

1. A mounting assembly for mounting a riving knife of a table saw to a motor arm of the table saw, the riving knife having an arcuate slot extending along a length of the riving knife that allows adjustment of an angular position of the riving knife relative to a saw blade and to a workpiece being cut by the blade, the mounting assembly comprising:
a mounting bracket mountable to the motor arm of the table saw, the mounting bracket including a clamping plate defining a clamping surface facing the riving knife;
a locking plate defining a locking surface facing the riving knife and the clamping plate;
a tab and recess arrangement defined by the mounting bracket and the locking plate, the locking plate including a plurality of peripheral edges, at least one of the peripheral edges interrupted by a vertical slot having a single monolithic tab projecting substantially perpendicular relative to the locking surface, the single tab sized to extend through and in a running fit with the arcuate slot of the riving knife, and the clamping plate including a recess sized to receive the tab when the tab extends through the arcuate slot; and
a lever assembly engaged between the mounting bracket and locking plate and operable to press the mounting bracket and locking plate together about the riving knife to clamp the riving knife between the clamping surface and the locking surface, the lever assembly including;
an elongated locking shaft extending through shaft openings in the mounting bracket and the locking plate, the locking shaft configured to extend through the arcuate slot in the riving knife;
one end of the locking shaft fastened to the clamping plate;
an opposite end of the locking shaft including a lever hub rotatably mounted thereon, the lever hub including a manually engagable lever for rotating the lever hub relative to the locking shaft;
a spring arrangement mounted on the locking shaft between the lever hub and the locking plate; and
a cam arrangement between the locking shaft and the lever hub operable to pull the locking shaft toward the lever hub upon rotation of the lever hub, to thereby pull the clamping plate toward the locking plate against a force of the spring arrangement to thereby clamp the riving knife between the clamping surface and locking surface.

2. The mounting assembly of claim 1 , wherein the spring arrangement includes at least one bevel washer.

3. The mounting assembly of claim 2 , wherein the spring arrangement includes two bevel washers opposing each other.

4. The mounting assembly of claim 1 , wherein:
the lever hub defines a bore therethrough and an arcuate cam slot in communication with the bore;
the locking shaft includes a shaft hub at the opposite end, the shaft hub received within the bore of the lever hub and sized to permit rotation of the lever hub relative to the shaft hub, the shaft hub including a pin projecting from the shaft hub and into the arcuate cam slot;
the cam slot configured to move the pin toward or away from the clamping plate upon rotation of the lever hub.

5. The mounting assembly of claim 1 in which the riving knife includes at least one pair of openings therethrough flanking the arcuate slot, wherein:
one of the clamping plate and the locking plate includes a pair of bosses corresponding to the pair of openings in the riving knife; and
the other of the clamping plate and the locking plate includes a pair of openings corresponding to the pair of bosses, the bosses sized to extend through the pair of openings in the riving knife and the pair of openings in the other of the clamping plate and the locking plate only when the riving knife is clamped between the clamping plate and locking plate.

6. The mounting assembly of claim 1 , wherein:
the locking shaft includes a keyed portion extending through the shaft opening in the clamping plate; and
the shaft opening of the clamping plate is complementary configured to the keyed portion to prevent rotation of the locking shaft relative to the clamping plate.

7. The mounting assembly of claim 1 , wherein the mounting bracket includes a mounting plate defining at least one fastener opening to receive a fastener for engaging the motor arm of the table saw, the clamping plate extending perpendicularly from the mounting plate.

8. The mounting assembly of claim 7 , wherein the mounting plate includes two fastener openings that are elongated in a direction perpendicular to the clamping plate to permit adjustment of a position of the clamping plate relative to the motor arm when the mounting bracket is engaged to the motor arm.

9. The mounting assembly of claim 7 , wherein the mounting bracket includes at least one adjustment screw extending through a threaded adjustment opening in the mounting plate and arranged to bear on the motor arm when the mounting plate is engaged to the motor arm to adjust a position of the mounting bracket relative to the motor arm.

10. The mounting assembly of claim 1 , further comprising:
a shoulder screw extending through the locking plate, through the arcuate slot in the riving knife and fastened to the clamping plate at a position below the elongated locking shaft relative to the length of the riving knife, the shoulder screw having a head at one end and a threaded end fastened to the clamping plate; and
a spring disposed between the head and the locking plate applying a spring force between the clamping plate and locking plate, the spring sized and configured to only apply a spring force that is insufficient to clamp the riving knife between the clamping plate and the locking plate.

11. The mounting assembly of claim 10 in which the riving knife includes at least one pair of openings therethrough flanking the arcuate slot, wherein:
one of the clamping plate and the locking plate includes a pair of bosses corresponding to the pair of openings in the riving knife; and
the other of the clamping plate and the locking plate includes a pair of openings corresponding to the pair of bosses, the bosses sized to extend through the pair of openings in the riving knife and the pair of openings in the other of the clamping plate and the locking plate only when the riving knife is clamped between the clamping plate and locking plate.

12. The mounting assembly of claim 1 , further comprising:
a U-shaped spring engaging the clamping plate and the locking plate at a position below the elongated locking shaft relative to the length of the riving knife to sandwich the riving knife between the clamping plate and the locking plate, the spring sized and configured to only apply a spring force that is insufficient to clamp the riving knife between the clamping plate and the locking plate.

13. A riving knife assembly for a table saw having motor-driven saw blade supported on a motor arm, comprising:
a riving knife having an arcuate slot extending along a length of the riving knife that allows adjustment of an angular position of the riving knife relative to a saw blade and to a workpiece being cut by the blade; and
a mounting assembly for mounting the riving knife to the motor arm including;
a mounting bracket mountable to the motor arm of the table saw, the mounting bracket including a clamping plate defining a clamping surface facing the riving knife;
a locking plate defining a locking surface facing the riving knife and the clamping plate;
a tab and recess arrangement defined by the mounting bracket and the locking plate, the locking plate including a plurality of peripheral edges, at least one of the peripheral edges interrupted by a vertical slot having a single monolithic tab projecting substantially perpendicula

Assignees

• Frolov Andrew
• Bosch Tool Corp
• Bosch Gmbh Robert

Inventors

• Frolov Andrew

Classifications

• B27G19/08 Primary

  Accessories for keeping open the saw kerf, e.g. riving knives or wedge plates · CPC title

• B23D45/061

  the saw blade being mounted on a carriage · CPC title

• B27G19/02 Primary

  for circular saws · CPC title