U.S. patent application number 09/977119 was filed with the patent office on 2002-03-14 for combination workpiece positioning/hold-down and anti-kickback device for a work table.
Invention is credited to Jukoff, Peter.
Application Number | 20020029822 09/977119 |
Document ID | / |
Family ID | 27617356 |
Filed Date | 2002-03-14 |
United States Patent
Application |
20020029822 |
Kind Code |
A1 |
Jukoff, Peter |
March 14, 2002 |
Combination workpiece positioning/hold-down and anti-kickback
device for a work table
Abstract
A combination workpiece positioning, hold-down and anti-kickback
device for a work table having a fence against which a workpiece is
guided, includes a non-rotatable positioning member having an
arcuate cam surface at one edge for engaging a side surface of a
workpiece on the work table; an adjustment device for moving the
positioning member in lengthwise and transverse directions relative
to the workpiece and for locking the same thereat; a pivot
pivotally mounting the positioning member to the adjustment device;
a spring connected between the positioning member and the
adjustment device for biasing the positioning member in a pivot
direction into engagement with the side surface of the workpiece; a
variable tensioning device for variably adjusting the biasing force
of the spring; a non-rotatable hold-down member having a second
arcuate cam surface at one edge for engaging an upper surface of
the workpiece; an adjustment device for moving the hold-down member
in lengthwise and vertical directions relative to the workpiece,
and for locking the same thereat; a pivot pivotally mounting the
hold-down member to the second adjustment device; a second spring
connected between the hold-down member and the adjustment device
for biasing the hold-down member in a second pivot direction into
engagement with the upper surface of the workpiece; and a second
variable tensioning device for variably adjusting the biasing force
of the second spring.
Inventors: |
Jukoff, Peter; (Richmond
Hill, NY) |
Correspondence
Address: |
FRISHAUF, HOLTZ, GOODMAN, LANGER & CHICK, P.C.
767 THIRD AVENUE
NEW YORK
NY
10017-2023
US
|
Family ID: |
27617356 |
Appl. No.: |
09/977119 |
Filed: |
October 12, 2001 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09977119 |
Oct 12, 2001 |
|
|
|
09482772 |
Jan 13, 2000 |
|
|
|
6315016 |
|
|
|
|
60115932 |
Jan 14, 1999 |
|
|
|
Current U.S.
Class: |
144/253.6 |
Current CPC
Class: |
B27B 29/00 20130101;
B23D 47/04 20130101; B27G 21/00 20130101; B23Q 3/002 20130101; B27G
19/02 20130101; B27C 5/06 20130101 |
Class at
Publication: |
144/253.6 |
International
Class: |
B27C 001/12; B27C
005/02; B27B 031/00 |
Claims
What is claimed is:
1. A combination workpiece positioning and anti-kickback device for
a work table having a fence against which a workpiece is guided,
comprising: a positioning member having a main body, and an arcuate
cam surface at one edge of the main body for engaging a side
surface of a workpiece on the work table; an adjustment device for
moving the positioning member relative to the workpiece, the
adjustment device including: a lengthwise adjustment assembly
movable in a lengthwise direction of movement of the workpiece
along the work table for adjusting the position of the positioning
member in said lengthwise direction, and a transverse adjustment
assembly movable in a direction transverse relative to said
lengthwise direction for adjusting the position of the positioning
member in the transverse direction, the transverse adjustment
assembly being movably connected to the lengthwise adjustment
assembly; a lengthwise releasable locking device for releasably
locking the lengthwise adjustment assembly relative to the work
table at a desired location in the lengthwise direction; a
transverse releasable locking device for releasably locking the
transverse adjustment assembly relative to the work table at a
desired location in the transverse direction; a pivot which
pivotally mounts the positioning member to the adjustment device
for pivoting movement; a spring connected between the positioning
member and the adjustment device for biasing the positioning member
with a biasing force in a first pivot direction about said pivot
such that said arcuate cam surface is biased in a direction
opposite to a feed direction of said workpiece and into engagement
with the side surface of the workpiece; and a variable tensioning
device for variably adjusting the biasing force of the spring,
wherein said lengthwise adjustment assembly includes at least first
and second lengthwise adjustment members, the first lengthwise
adjustment member being received within an interior portion of the
second lengthwise adjustment member.
2. The combination workpiece positioning and anti-kickback device
according to claim 1, wherein said first lengthwise adjustment
member includes a plurality of apertures along at least one side
thereof and wherein the lengthwise releasable locking device
comprises a retractable pin operatively coupled to said second
lengthwise adjustment member for releasably engaging one of the
plurality of apertures of the first lengthwise adjustment member
such that the first lengthwise adjustment member is releasably
coupled to the second lengthwise adjustment member and such that
the positioning member is situated at a desired lengthwise location
on the work table.
3. The combination workpiece positioning and anti-kickback device
according to claim 1, wherein said lengthwise adjustment assembly
further comprises a third lengthwise adjustment member, the first
lengthwise adjustment member being received within an interior
portion of the third lengthwise adjustment member.
4. The combination workpiece positioning and anti-kickback device
according to claim 3 wherein said first lengthwise adjustment
member includes a plurality of apertures along at least one side
thereof and wherein the lengthwise releasable locking device
comprises a retractable pin operatively coupled to said third
lengthwise adjustment member for releasably engaging one of the
plurality of apertures of the first lengthwise adjustment member
such that the first lengthwise adjustment member is releasably
coupled to the third lengthwise adjustment member and such that the
positioning member is positioned at a desired location.
5. The combination workpiece positioning and anti-kickback device
according to claim 3, wherein said third lengthwise adjustment
member is collinear with said second lengthwise adjustment member
with a gap between said second and third lengthwise adjustment
members in which said first lengthwise adjustment member is
located.
6. The combination workpiece positioning and anti-kickback device
according to claim 1, wherein: said transverse adjustment assembly
includes: a first abutment secured to said second lengthwise
adjustment member for engaging one transverse side of the work
table; and a second abutment secured to said third lengthwise
adjustment member for engaging an opposite transverse side of the
work table; and said transverse releasable locking device includes:
a first and second releasable clamps respectively secured to said
second and third lengthwise adjustment members for moving said
first and second abutments into releasable engagement with the work
table; and a threaded rod which respectively connects the first and
second abutments to the first and second releasable clamps with an
adjustable distance therebetween.
7. The combination workpiece positioning and anti-kickback device
according to claim 1, wherein said main body is oriented
substantially in said transverse direction, and said arcuate cam
surface has a curvature with an increasing radius in a direction
opposite to the direction of movement of said workpiece along the
work table such that smaller radius portions of said arcuate cam
surface extend closer toward the workpiece than larger radius
portions of said arcuate cam surface.
8. The combination workpiece positioning and anti-kickback device
according to claim 1, wherein said main body has an oblong
shape.
9. The combination workpiece positioning and anti-kickback device
according to claim 1, wherein said pivot pivotally mounts the
positioning member to the lengthwise adjustment member for pivoting
movement.
10. The combination workpiece positioning and anti-kickback device
according to claim 1, further comprising a stop disposed on said
lengthwise adjustment assembly for limiting pivotal movement of
said positioning member.
11. The combination workpiece positioning and anti-kickback device
according to claim 1, wherein said variable tensioning device
includes a threaded tensioning rod connected between said spring
and said lengthwise adjusting assembly, and threadedly connected
with said lengthwise adjustment assembly for variably changing the
biasing force of the spring.
12. The combination workpiece positioning and anti-kickback device
according to claim 1, further comprising a positioning adjustment
member including a threaded rod extending through an interior
portion of the second lengthwise adjustment member and being
operatively engaged with the first lengthwise adjustment member for
altering and fixing a position of the first adjustment member with
respect to the second adjustment member.
13. A combination workpiece positioning and anti-kickback device
for a work table having a fence against which a workpiece is
guided, comprising: a positioning member having a main body, and an
arcuate cam surface at one edge of the main body for engaging a
side surface of a workpiece on the work table; an adjustment device
for moving the positioning member relative to the workpiece, the
adjustment device including: a lengthwise adjustment assembly
movable in a lengthwise direction of movement of the workpiece
along the work table for adjusting the position of the positioning
member in said lengthwise direction, and a transverse adjustment
assembly movable in a direction transverse to said lengthwise
direction for adjusting the position of the positioning member in
the transverse direction, the transverse adjustment assembly being
movably connected to the lengthwise adjustment assembly; a
lengthwise releasable locking device for releasably locking the
lengthwise adjustment assembly relative to the work table at a
desired location in the lengthwise direction; a transverse
releasable locking device for releasably locking the transverse
adjustment assembly relative to the work table at a desired
location in the transverse direction; a pivot which pivotally
mounts the positioning member to the adjustment device for pivoting
movement; a spring connected between the positioning member and the
adjustment device for biasing the positioning member with a biasing
force in a first pivot direction about said pivot such that said
arcuate cam surface is biased in a direction opposite to a feed
direction of said workpiece and into engagement with the side
surface of the workpiece; and a variable tensioning device for
variably adjusting the biasing force of the spring, wherein said
lengthwise adjustment assembly includes a lengthwise adjustment
member operatively engaged within a guide track of the work
table.
14. The combination workpiece positioning and anti-kickback device
according to claim 13, wherein the lengthwise adjustment member
includes a guide rail slidably engagable in said guide track of
said work table.
15. The combination workpiece positioning and anti-kickback device
according to claim 13, wherein said lengthwise releasable locking
device includes a releasable clamping device which engages the
guide track to releasably fix the lengthwise adjustment member to
the work table at a desired location therealong.
16. The combination workpiece positioning and anti-kickback device
according to claim 13, wherein said transverse adjustment assembly
comprises: a traverse adjustment member operatively coupled to the
lengthwise adjustment member, the positioning member being
operatively coupled to the transverse adjustment member.
17. The combination workpiece positioning and anti-kickback device
according to claim 16, wherein the transverse adjustment member
includes an aperture whose length extends in a direction which is
non-parallel with respect to the guide track, and a clamping device
engaging the lengthwise adjustment member to releasably fix the
transverse adjustment member to the lengthwise adjustment
member.
18. The combination workpiece positioning and anti-kickback device
according to claim 17, wherein at least a portion of the clamping
device is engaged within the aperture of said transverse adjustment
member.
19. The combination workpiece positioning and anti-kickback device
according to claim 13, wherein said main body is oriented
substantially in said transverse direction, and said arcuate cam
surface has a curvature with an increasing radius in a direction
opposite to the direction of movement of said workpiece along the
work table such that smaller radius portions of said arcuate cam
surface extend closer toward the workpiece than larger radius
portions of said arcuate cam surface.
20. The combination workpiece positioning and anti-kickback device
according to claim 13, wherein said main body has an oblong
shape.
21. The combination workpiece positioning and anti-kickback device
according to claim 13, wherein said pivot pivotally mounts the
positioning member to the lengthwise adjustment member.
22. The combination workpiece positioning and anti-kickback device
according to claim 13, further comprising a stop on said lengthwise
adjustment assembly for limiting pivotal movement of said
positioning member.
23. The combination workpiece positioning and anti-kickback device
according to claim 13, wherein said variable tensioning device
includes a threaded tensioning rod connected between said spring
and said lengthwise adjusting assembly, and threadedly connected
with said lengthwise adjustment assembly for variably changing the
biasing force of the spring.
24. A combination workpiece hold-down and anti-kickback device for
a work table having a fence against which a workpiece is guided,
comprising: a hold-down member having a main body, and an arcuate
cam surface at one edge of the main body for engaging an upper
surface of a workpiece on the work table; an adjustment device for
moving the hold-down member relative to the workpiece, the
adjustment device including: a lengthwise adjustment assembly
movable in a lengthwise direction of movement of the workpiece
along the work table for adjusting the position of the hold-down
member in said lengthwise direction, and a vertical adjustment
assembly movable in a vertical direction transverse to said
lengthwise direction for adjusting the position of the hold-down
member in the vertical direction, the vertical adjustment assembly
being movably connected to the lengthwise adjustment assembly; a
lengthwise releasable locking device for releasably locking the
lengthwise adjustment assembly relative to the work table at a
desired location in the lengthwise direction; a vertical releasable
locking device for releasably locking the vertical adjustment
assembly relative to the work table at a desired location in the
vertical direction; a pivot which pivotally mounts the hold-down
member to the adjustment device for pivoting movement; a spring
connected between the hold-down member and the adjustment device
for biasing the hold-down member with a biasing force in a first
pivot direction about said pivot such that said arcuate cam surface
is biased in a direction opposite to a feed direction of said
workpiece and into engagement with the upper surface of the
workpiece; and a variable tensioning device for variably adjusting
the biasing force of the spring, wherein said vertical adjustment
assembly includes a vertical adjustment member operatively coupled
to said lengthwise adjustment assembly, said vertical adjustment
member including an aperture whose length extends in a direction
which is non-parallel with respect to a longitudinal length of the
lengthwise adjustment assembly, and a clamping device engaging said
vertical adjustment member so as to releasably fix a height of the
hold-down member with respect to the work table.
25. The combination workpiece hold-down and anti-kickback device
according to claim 24 wherein at least a portion of the clamping
device is engaged within said aperture of said vertical adjustment
assembly, and wherein said clamping device operatively engages said
hold-down member.
26. The combination workpiece hold-down and anti-kickback device
according to claim 24, wherein said main body is oriented
substantially in said vertical direction, and said arcuate cam
surface has a curvature with an increasing radius in a direction
opposite to the direction of movement of said workpiece along the
work table such that smaller radius portions of said arcuate cam
surface extend closer toward the workpiece than larger radius
portions of said arcuate cam surface.
27. The combination workpiece hold-down and anti-kickback device
according to claim 24, wherein said main body has an oblong
shape.
28. The combination workpiece hold-down and anti-kickback device
according to claim 24, wherein said lengthwise adjustment assembly
includes a guide track extending in said lengthwise direction, and
a guide rail movable in said guide track in said lengthwise
direction, with said vertical adjustment assembly being mounted to
said guide rail.
29. The combination workpiece hold-down and anti-kickback device
according to claim 28, wherein said lengthwise releasable locking
device includes a releasable clamping device for releasably
clamping the guide rail to the guide track at a desired location
therealong.
30. The combination workpiece hold-down and anti-kickback device
according to claim 24, wherein said pivot pivotally mounts the
hold-down member to the vertical adjustment member for pivoting
movement.
31. The combination workpiece hold-down and anti-kickback device
according to claim 24, further comprising a stop on said vertical
adjustment assembly for limiting pivotal movement of said hold-down
member.
32. The combination workpiece hold-down and anti-kickback device
according to claim 24, wherein said variable tensioning device
includes a threaded tensioning rod connected between said spring
and said vertical adjustment assembly, and threadedly connected
with said vertical adjustment assembly for variably changing the
biasing force of the spring.
33. A combination workpiece positioning, hold-down and
anti-kickback device for a work table having a fence against which
a workpiece is guided, comprising: a first positioning member
having a main body, and a first arcuate cam surface at one edge of
the main body for engaging a side surface of a workpiece on the
work table; a first adjustment device for moving the first
positioning member relative to the workpiece, the adjustment device
including: a first lengthwise adjustment assembly movable in a
lengthwise direction of movement of the workpiece along the work
table for adjusting the position of the positioning member in said
lengthwise direction, and a first transverse adjustment assembly
movable in a direction transverse to said lengthwise direction for
adjusting the position of the positioning member in the transverse
direction, the transverse adjustment assembly being movably
connected to the lengthwise adjustment assembly; a first lengthwise
releasable locking device for releasably locking the lengthwise
adjustment assembly relative to the work table at a desired
location in the lengthwise direction; a first transverse releasable
locking device for releasably locking the transverse adjustment
assembly relative to the work table at a desired location in the
transverse direction; a first pivot which pivotally mounts the
positioning member to the adjustment device for pivoting movement;
a first spring connected between the positioning member and the
adjustment device for biasing the positioning member with a biasing
force in a first pivot direction about said pivot such that said
arcuate cam surface is biased in a direction opposite to a feed
direction of said workpiece into engagement with the side surface
of the workpiece; a first variable tensioning device for variably
adjusting the biasing force of the spring; a hold-down member
having a main body, and a second arcuate cam surface at one edge of
the main body for engaging an upper surface of a workpiece on the
work table; a second adjustment device for moving the hold-down
member relative to the workpiece, the second adjustment device
including: a second lengthwise adjustment assembly movable in said
lengthwise direction for adjusting the position of the hold-down
member in said lengthwise direction, and a vertical adjustment
assembly movable in a vertical direction transverse to said
lengthwise direction for adjusting the position of the hold-down
member in the vertical direction, the vertical adjustment assembly
being movably connected to the lengthwise adjustment assembly; a
second lengthwise releasable locking device for releasably locking
the second lengthwise adjustment assembly relative to the work
table at a desired location in the lengthwise direction; a vertical
releasable locking device for releasably locking the vertical
adjustment assembly relative to the work table at a desired
location in the vertical direction; a second pivot which pivotally
mounts the hold-down member to the second adjustment device for
pivoting movement; a second spring connected between the hold-down
member and the second adjustment device for biasing the hold-down
member with a biasing force in a second pivot direction about said
second pivot such that said second arcuate cam surface is biased in
a direction opposite to the feed direction of said workpiece and
into engagement with the upper surface of the workpiece; and a
second variable tensioning device for variably adjusting the
biasing force of the second spring, wherein said first lengthwise
adjustment assembly includes at least first and second lengthwise
adjustment members, the first lengthwise adjustment member being
received within an interior portion of the second lengthwise
adjustment member.
34. A combination workpiece positioning, hold-down and
anti-kickback device for a work table having a fence against which
a workpiece is guided, comprising: a first positioning member
having a main body, and a first arcuate cam surface at one edge of
the main body for engaging a side surface of a workpiece on the
work table; a first adjustment device for moving the first
positioning member relative to the workpiece, the adjustment device
including: a first lengthwise adjustment assembly movable in a
lengthwise direction of movement of the workpiece along the work
table for adjusting the position of the positioning member in said
lengthwise direction, and a first transverse adjustment assembly
movable in a direction transverse to said lengthwise direction for
adjusting the position of the positioning member in the transverse
direction, the transverse adjustment assembly being movably
connected to the lengthwise adjustment assembly; a first lengthwise
releasable locking device for releasably locking the lengthwise
adjustment assembly relative to the work table at a desired
location in the lengthwise direction; a first transverse releasable
locking device for releasably locking the transverse adjustment
assembly relative to the work table at a desired location in the
transverse direction; a first pivot which pivotally mounts the
positioning member to the adjustment device for pivoting movement;
a first spring connected between the positioning member and the
adjustment device for biasing the positioning member with a biasing
force in a first pivot direction about said pivot such that said
arcuate cam surface is biased in a direction opposite to a feed
direction of said workpiece into engagement with the side surface
of the workpiece; a first variable tensioning device for variably
adjusting the biasing force of the spring; a hold-down member
having a main body, and a second arcuate cam surface at one edge of
the main body for engaging an upper surface of a workpiece on the
work table; a second adjustment device for moving the hold-down
member relative to the workpiece, the second adjustment device
including: a second lengthwise adjustment assembly movable in said
lengthwise direction for adjusting the position of the hold-down
member in said lengthwise direction, and a vertical adjustment
assembly movable in a vertical direction transverse to said
lengthwise direction for adjusting the position of the hold-down
member in the vertical direction, the vertical adjustment assembly
being movably connected to the lengthwise adjustment assembly; a
second lengthwise releasable locking device for releasably locking
the second lengthwise adjustment assembly relative to the work
table at a desired location in the lengthwise direction; a vertical
releasable locking device for releasably locking the vertical
adjustment assembly relative to the work table at a desired
location in the vertical direction; a second pivot which pivotally
mounts the hold-down member to the second adjustment device for
pivoting movement; a second spring connected between the hold-down
member and the second adjustment device for biasing the hold-down
member with a biasing force in a second pivot direction about said
second pivot such that said second arcuate cam surface is biased in
a direction opposite to the feed direction of said workpiece and
into engagement with the upper surface of the workpiece; and a
second variable tensioning device for variably adjusting the
biasing force of the second spring wherein said first lengthwise
adjustment assembly includes a lengthwise adjustment member
operatively engaged within a guide track of the work table, wherein
said vertical adjustment assembly includes a vertical adjustment
member operatively coupled to said second lengthwise adjustment
assembly, said vertical adjustment member including an aperture
whose length extends in a direction which is non-parallel with
respect to a longitudinal length of the second lengthwise
adjustment assembly, and a clamping device engaging said vertical
adjustment member so as to releasably fix a height of the hold down
member with respect to the work table.
35. A combination workpiece positioning, hold-down and
anti-kickback device for a work table having a fence against which
a workpiece is guided, comprising: a first positioning member
having a main body, and a first arcuate cam surface at one edge of
the main body for engaging a side surface of a workpiece on the
work table; a first adjustment device for moving the first
positioning member relative to the workpiece, the adjustment device
including: a first lengthwise adjustment assembly movable in a
lengthwise direction of movement of the workpiece along the work
table for adjusting the position of the positioning member in said
lengthwise direction, and a first transverse adjustment assembly
movable in a direction transverse to said lengthwise direction for
adjusting the position of the positioning member in the transverse
direction, the transverse adjustment assembly being movably
connected to the lengthwise adjustment assembly; a first lengthwise
releasable locking device for releasably locking the lengthwise
adjustment assembly relative to the work table at a desired
location in the lengthwise direction; a first transverse releasable
locking device for releasably locking the transverse adjustment
assembly relative to the work table at a desired location in the
transverse direction; a first pivot which pivotally mounts the
positioning member to the adjustment device for pivoting movement;
a first spring connected between the positioning member and the
adjustment device for biasing the positioning member with a biasing
force in a first pivot direction about said pivot such that said
arcuate cam surface is biased in a direction opposite to a feed
direction of said workpiece into engagement with the side surface
of the workpiece; a first variable tensioning device for variably
adjusting the biasing force of the spring; a hold-down member
having a main body, and a second arcuate cam surface at one edge of
the main body for engaging an upper surface of a workpiece on the
work table; a second adjustment device for moving the hold-down
member relative to the workpiece, the second adjustment device
including: a second lengthwise adjustment assembly movable in said
lengthwise direction for adjusting the position of the hold-down
member in said lengthwise direction, and a vertical adjustment
assembly movable in a vertical direction transverse to said
lengthwise direction for adjusting the position of the hold-down
member in the vertical direction, the vertical adjustment assembly
being movably connected to the lengthwise adjustment assembly; a
second lengthwise releasable locking device for releasably locking
the second lengthwise adjustment assembly relative to the work
table at a desired location in the lengthwise direction; a vertical
releasable locking device for releasably locking the vertical
adjustment assembly relative to the work table at a desired
location in the vertical direction; a second pivot which pivotally
mounts the hold-down member to the second adjustment device for
pivoting movement; a second spring connected between the hold-down
member and the second adjustment device for biasing the hold-down
member with a biasing force in a second pivot direction about said
second pivot such that said second arcuate cam surface is biased in
a direction opposite to the feed direction of said workpiece and
into engagement with the upper surface of the workpiece; and a
second variable tensioning device for variably adjusting the
biasing force of the second spring wherein said first lengthwise
adjustment assembly includes a lengthwise adjustment member
operatively engaged within a guide track of the work table, wherein
said first lengthwise adjustment assembly includes a lengthwise
adjustment member operatively engaged within a guide track of the
work table.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 USC 120 of
application Ser. No. 09/482,772, filed Jan. 13, 2000, which claims
the benefit of Provisional Application Serial No. 60/115,932 filed
Jan. 14, 1999, the entire contents of which are incorporated herein
by reference.
BACKGROUND INFORMATION
[0002] The present invention relates generally to work tables for
power tools and the like, and is more particularly directed to a
combination workpiece positioning/hold-down and anti-kickback
device for a work table.
[0003] A work table for a woodworking device, such as a power saw,
router and the like, generally includes a horizontal tabletop on
which the workpiece is supported and a fence secured to the
tabletop and extending in the direction of movement of the
workpiece. The workpiece is moved on the upper surface of the
tabletop and is guided along the fence, during a cutting or other
woodworking action.
[0004] Featherboard and other devices are known for pressing the
workpiece against the fence during such movement, and various
hold-down devices are known for pressing the upper surface of the
workpiece to hold the workpiece down on the tabletop. These devices
have some of the following desirable features.
[0005] One such desirable feature is the ability to prevent
kick-back of the workpiece during a woodworking operation. Another
desirable feature is the adjustment of the positioning or hold-down
member in lengthwise, transverse and vertical directions relative
to the workpiece. Still another desirable feature is the ability to
variably adjust the biasing force of the positioning or hold-down
member against the workpiece. The applicant is not aware, however,
of any devices that include all of these features in a simple
arrangement.
OBJECTS AND SUMMARY OF THE INVENTION
[0006] Accordingly, it is an object of the present invention to
provide a combination workpiece positioning/hold-down and
anti-kickback device that overcomes inherent disadvantages of know
workpiece positioning/hold-down devices.
[0007] It is another object of the present invention to provide a
combination workpiece positioning/hold-down and anti-kickback
device that presses the side and/or top surface of the workpiece,
while preventing kick-back thereof.
[0008] It is still another object of the present invention to
provide a combination workpiece positioning/hold-down and
anti-kickback device in which the positioning or hold-down member
is adjustable in lengthwise, transverse and vertical directions
relative to the workpiece.
[0009] It is yet another object of the present invention to provide
a combination workpiece positioning/hold-down and anti-kickback
device in which the biasing force of the positioning or hold-down
member against the workpiece is variably adjustable.
[0010] In accordance with one form of the present invention, a
combination workpiece positioning and anti-kickback device for a
work table having a fence against which a workpiece is guided,
includes a positioning member having a main body, and an arcuate
cam surface at one edge of the main body for engaging a side
surface of a workpiece on the work table; an adjustment device for
moving the positioning member relative to the workpiece, the
adjustment device including a lengthwise adjustment assembly
movable in a lengthwise direction of movement of the workpiece
along the work table for adjusting the position of the positioning
member in the lengthwise direction, and a transverse adjustment
assembly movable in a direction transverse to the lengthwise
direction for adjusting the position of the positioning member in
the transverse direction, the transverse adjustment assembly being
movably connected to the lengthwise adjustment assembly; a
lengthwise releasable locking device for releasably locking the
lengthwise adjustment assembly relative to the work table at a
desired location in the lengthwise direction; a transverse
releasable locking device for releasably locking the transverse
adjustment assembly relative to the work table at a desired
location in the transverse direction; a pivot which pivotally
mounts the positioning member to the adjustment device for pivoting
movement; a spring connected between the positioning member and the
adjustment device for biasing the positioning member with a biasing
force in a first pivot direction about the pivot such that the
arcuate cam surface is biased in a direction opposite to a feed
direction of the workpiece and into engagement with the side
surface of the workpiece; and a variable tensioning device for
variably adjusting the biasing force of the spring, wherein the
lengthwise adjustment assembly includes at least first and second
lengthwise adjustment members, the first lengthwise adjustment
member being received within an interior portion of the second
lengthwise adjustment member.
[0011] In accordance with another form of the present invention, a
combination workpiece positioning and anti-kickback device for a
work table having a fence against which a workpiece is guided,
includes a positioning member having a main body, and an arcuate
cam surface at one edge of the main body for engaging a side
surface of a workpiece on the work table; an adjustment device for
moving the positioning member relative to the workpiece, the
adjustment device including a lengthwise adjustment assembly
movable in a lengthwise direction of movement of the workpiece
along the work table for adjusting the position of the positioning
member in said lengthwise direction, and a transverse adjustment
assembly movable in a direction transverse to said lengthwise
direction for adjusting the position of the positioning member in
the transverse direction, the transverse adjustment assembly being
movably connected to the lengthwise adjustment assembly; a
lengthwise releasable locking device for releasably locking the
lengthwise adjustment assembly relative to the work table at a
desired location in the lengthwise direction; a transverse
releasable locking device for releasably locking the transverse
adjustment assembly relative to the work table at a desired
location in the transverse direction; a pivot which pivotally
mounts the positioning member to the adjustment device for pivoting
movement; a spring connected between the positioning member and the
adjustment device for biasing the positioning member with a biasing
force in a first pivot direction about said pivot such that said
arcuate cam surface is biased in a direction opposite to a feed
direction of said workpiece and into engagement with the side
surface of the workpiece; and a variable tensioning device for
variably adjusting the biasing force of the spring, wherein the
lengthwise adjustment assembly includes a lengthwise adjustment
member operatively engaged within a guide track of the work
table.
[0012] In accordance with another form of the present invention, a
combination workpiece hold-down and anti-kickback device for a work
table having a fence against which a workpiece is guided, includes
a hold-down member having a main body, and an arcuate cam surface
at one edge of the main body for engaging an upper surface of a
workpiece on the work table; an adjustment device for moving the
hold-down member relative to the workpiece, the adjustment device
including a lengthwise adjustment assembly movable in a lengthwise
direction of movement of the workpiece along the work table for
adjusting the position of the hold-down member in the lengthwise
direction, and a vertical adjustment assembly movable in a vertical
direction transverse to the lengthwise direction for adjusting the
position of the hold-down member in the vertical direction, the
vertical adjustment assembly being movably connected to the
lengthwise adjustment assembly; a lengthwise releasable locking
device for releasably locking the lengthwise adjustment assembly
relative to the work table at a desired location in the lengthwise
direction; a vertical releasable locking device for releasably
locking the vertical adjustment assembly relative to the work table
at a desired location in the vertical direction; a pivot which
pivotally mounts the hold-down member to the adjustment device for
pivoting movement; a spring connected between the hold-down member
and the adjustment device for biasing the hold-down member with a
biasing force in a first pivot direction about the pivot such that
the arcuate cam surface is biased in a direction opposite to a feed
direction of the workpiece and into engagement with the upper
surface of the workpiece; and a variable tensioning device for
variably adjusting the biasing force of the spring, wherein said
vertical adjustment assembly includes a vertical adjustment member
operatively coupled to said lengthwise adjustment assembly, said
vertical adjustment member including an aperture whose length
extends in a direction which is non-parallel with respect to a
longitudinal length of the lengthwise adjustment assembly, and a
clamping device engaging said vertical adjustment member so as to
releasably fix a height of the hold-down member with respect to the
work table.
[0013] In accordance with another form of the present invention, a
combination workpiece positioning, hold-down and anti-kickback
device for a work table having a fence against which a workpiece is
guided, includes a first positioning member having a main body, and
a first arcuate cam surface at one edge of the main body for
engaging a side surface of a workpiece on the work table; a first
adjustment device for moving the first positioning member relative
to the workpiece, the adjustment device including a first
lengthwise adjustment assembly movable in a lengthwise direction of
movement of the workpiece along the work table for adjusting the
position of the positioning member in the lengthwise direction, and
a first transverse adjustment assembly movable in a direction
transverse to the lengthwise direction for adjusting the position
of the positioning member in the transverse direction, the
transverse adjustment assembly being movably connected to the
lengthwise adjustment assembly; a first lengthwise releasable
locking device for releasably locking the lengthwise adjustment
assembly relative to the work table at a desired location in the
lengthwise direction; a first transverse releasable locking device
for releasably locking the transverse adjustment assembly relative
to the work table at a desired location in the transverse
direction; a first pivot which pivotally mounts the positioning
member to the adjustment device for pivoting movement; a first
spring connected between the positioning member and the adjustment
device for biasing the positioning member with a biasing force in a
first pivot direction about the pivot such that the arcuate cam
surface is biased in a direction opposite to a feed direction of
the workpiece into engagement with the side surface of the
workpiece; a first variable tensioning device for variably
adjusting the biasing force of the spring; a non-rotatable
hold-down member having a main body, and a second arcuate cam
surface at one edge of the main body for engaging an upper surface
of a workpiece on the work table; a second adjustment device for
moving the hold-down member relative to the workpiece, the second
adjustment device including a second lengthwise adjustment assembly
movable in the lengthwise direction for adjusting the position of
the hold-down member in the lengthwise direction, and a vertical
adjustment assembly movable in a vertical direction transverse to
the lengthwise direction for adjusting the position of the
hold-down member in the vertical direction, the vertical adjustment
assembly being movably connected to the lengthwise adjustment
assembly; a second lengthwise releasable locking device for
releasably locking the second lengthwise adjustment assembly
relative to the work table at a desired location in the lengthwise
direction; a vertical releasable locking device for releasably
locking the vertical adjustment assembly relative to the work table
at a desired location in the vertical direction; a second pivot
which pivotally mounts the hold-down member to the second
adjustment device for pivoting movement; a second spring connected
between the hold-down member and the second adjustment device for
biasing the hold-down member with a biasing force in a second pivot
direction about the second pivot such that the second arcuate cam
surface is biased in a direction opposite to the feed direction of
the workpiece and into engagement with the upper surface of the
workpiece; and a second variable tensioning device for variably
adjusting the biasing force of the second spring, wherein the
lengthwise adjustment assembly includes at least first and second
lengthwise adjustment member, and the first lengthwise adjustment
member being received within an interior portion of the second
lengthwise adjustment member.
[0014] In accordance with another form of the present invention a
combination workpiece positioning, hold-down and anti-kickback
device for a work table having a fence against which a workpiece is
guided, includes a first positioning member having a main body, and
a first arcuate cam surface at one edge of the main body for
engaging a side surface of a workpiece on the work table; a first
adjustment device for moving the first positioning member relative
to the workpiece, the adjustment device including a first
lengthwise adjustment assembly movable in a lengthwise direction of
movement of the workpiece along the work table for adjusting the
position of the positioning member in said length-wise direction,
and a first transverse adjustment assembly movable in a direction
transverse to said lengthwise direction for adjusting the position
of the positioning member in the transverse direction, the
transverse adjustment assembly being movably connected to the
lengthwise adjustment assembly; a first lengthwise releasable
locking device for releasably locking the lengthwise adjustment
assembly relative to the work table at a desired location in the
lengthwise direction; a first transverse releasable locking device
for releasably locking the transverse adjustment assembly relative
to the work table at a desired location in the transverse
direction; a first pivot which pivotally mounts the positioning
member to the adjustment device for pivoting movement; a first
spring connected between the positioning member and the adjustment
device for biasing the positioning member with a biasing force in a
first pivot direction about said pivot such that said arcuate cam
surface is biased in a direction opposite to a feed direction of
said workpiece into engagement with the side surface of the
workpiece; a first variable tensioning device for variably
adjusting the biasing force of the spring; a hold-down member
having a main body, and a second arcuate cam surface at one edge of
the main body for engaging an upper surface of a workpiece on the
work table; a second adjustment device for moving the hold-down
member relative to the workpiece, the second adjustment device
including a second lengthwise adjustment assembly movable in said
lengthwise direction for adjusting the position of the hold-down
member in said lengthwise direction, and a vertical adjustment
assembly movable in a vertical direction transverse to said
lengthwise direction for adjusting the position of the hold-down
member in the vertical direction, the vertical adjustment assembly
being movably connected to the lengthwise adjustment assembly; a
second lengthwise releasable locking device for releasably locking
the second lengthwise adjustment assembly relative to the work
table at a desired location in the lengthwise direction; a vertical
releasable locking device for releasably locking the vertical
adjustment assembly relative to the work table at a desired
location in the vertical direction; a second pivot which pivotally
mounts the hold-down member to the second adjustment device for
pivoting movement; a second spring connected between the hold-down
member and the second adjustment device for biasing the hold-down
member with a biasing force in a second pivot direction about said
second pivot such that said second arcuate cam surface is biased in
a direction opposite to the feed direction of said workpiece and
into engagement with the upper surface of the workpiece; and a
second variable tensioning device for variably adjusting the
biasing force of the second spring, wherein said vertical
adjustment assembly includes a vertical adjustment member
operatively coupled to said lengthwise adjustment assembly, said
vertical adjustment member including an aperture whose length
extends in a direction which is non-parallel with respect to a
longitudinal length of the second lengthwise adjustment assembly,
and a clamping device engaging said vertical adjustment member so
as to releasably fix a height of the hold-down member with respect
to the work table.
[0015] In accordance with another form of the present invention, a
combination workpiece positioning, hold-down and anti-kickback
device for a work table having a fence against which a workpiece is
guided, includes a first positioning member having a main body, and
a first arcuate cam surface at one edge of the main body for
engaging a side surface of a workpiece on the work table; a first
adjustment device for moving the first positioning member relative
to the workpiece, the adjustment device including a first
lengthwise adjustment assembly movable in a lengthwise direction of
movement of the workpiece along the work table for adjusting the
position of the positioning member in said lengthwise direction,
and a first transverse adjustment assembly movable in a direction
transverse to said lengthwise direction for adjusting the position
of the positioning member in the transverse direction, the
transverse adjustment assembly being movably connected to the
lengthwise adjustment assembly; a first lengthwise releasable
locking device for releasably locking the lengthwise adjustment
assembly relative to the work table at a desired location in the
lengthwise direction; a first transverse releasable locking device
for releasably locking the transverse adjustment assembly relative
to the work table at a desired location in the transverse
direction; a first pivot which pivotally mounts the positioning
member to the adjustment device for pivoting movement; a first
spring connected between the positioning member and the adjustment
device for biasing the positioning member with a biasing force in a
first pivot direction about said pivot such that said arcuate cam
surface is biased in a direction opposite to a feed direction of
said workpiece into engagement with the side surface of the
workpiece; a first variable tensioning device for variably
adjusting the biasing force of the spring; a hold-down member
having a main body, and a second arcuate cam surface at one edge of
the main body for engaging an upper surface of a workpiece on the
work table; a second adjustment device for moving the hold-down
member relative to the workpiece, the second adjustment device
including a second lengthwise adjustment assembly movable in said
lengthwise direction for adjusting the position of the hold-down
member in said lengthwise direction, and a vertical adjustment
assembly movable in a vertical direction transverse to said
lengthwise direction for adjusting the position of the hold-down
member in the vertical direction, the vertical adjustment assembly
being movably connected to the lengthwise adjustment assembly; a
second lengthwise releasable locking device for releasably locking
the second lengthwise adjustment assembly relative to the work
table at a desired location in the lengthwise direction; a vertical
releasable locking device for releasably locking the vertical
adjustment assembly relative to the work table at a desired
location in the vertical direction; a second pivot which pivotally
mounts the hold-down member to the second adjustment device for
pivoting movement; a second spring connected between the hold-down
member and the second adjustment device for biasing the hold-down
member with a biasing force in a second pivot direction about said
second pivot such that said second arcuate cam surface is biased in
a direction opposite to the feed direction of said workpiece and
into engagement with the upper surface of the workpiece; and a
second variable tensioning device for variably adjusting the
biasing force of the second spring wherein said first lengthwise
adjustment assembly includes a lengthwise adjustment member
operatively engaged within a guide track of the work table, wherein
said first lengthwise adjustment assembly includes a lengthwise
adjustment member operatively engaged within a guide track of the
work table.
[0016] The above and other objects, features and advantages of the
present invention will become readily apparent from the following
detailed description of the preferred embodiments thereof, which is
to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a perspective view of the combination workpiece
positioning/hold-down and anti-kickback device according to the
present invention;
[0018] FIG. 2 is a front elevational view, partly in section, of
the combination workpiece positioning/hold-down and anti-kickback
device, as viewed along line 2-2 of FIG. 1;
[0019] FIG. 3 is an end elevational view, partly in section, of the
combination workpiece positioning/hold-down and anti-kickback
device, as viewed along line 3-3 of FIG. 2;
[0020] FIG. 4 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 4-4 of FIG. 2;
[0021] FIG. 5 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 5-5 of FIG. 2;
[0022] FIG. 6 is a top plan view, partly in section, of the
combination workpiece positioning/hold-down and anti-kickback
device, as viewed along line 6-6 of FIG. 1;
[0023] FIG. 7 is an end elevational view, partly in section, of the
combination workpiece positioning/hold-down and anti-kickback
device, as viewed along line 7-7 of FIG. 6;
[0024] FIG. 8 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 8-8 of FIG. 7; and
[0025] FIG. 9 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 9-9 of FIG. 7;
[0026] FIG. 10 is a top plan view, partly in section, of a modified
embodiment wherein locking teeth 56, 70 are replaced with mutually
engaging linear gear racks;
[0027] FIG. 11 is an end elevational view, partly in section, of
the modified embodiment of FIG. 10;
[0028] FIG. 12 is a cross-sectional view of the modified embodiment
shown in FIGS. 10 and 11, taken along line 12-12 in FIG. 11;
[0029] FIG. 13 is a perspective view of the combination workpiece
positioning/hold-down and anti-kickback device according to another
embodiment of the present invention;
[0030] FIG. 14 is a front elevational view, partly in section, of
the combination workpiece positioning/hold-down and anti-kickback
device, as viewed along line 14-14 of FIG. 13;
[0031] FIG. 15 is an end elevational view, partly in section, of
the combination workpiece positioning/hold-down and anti-kickback
device, as viewed along line 15-15 of FIG. 14;
[0032] FIG. 16 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 16-16 of FIG. 13;
[0033] FIG. 17 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 17-17 of FIG. 16;
[0034] FIG. 18 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 18-18 of FIG. 17;
[0035] FIG. 19 is a cross-sectional view of the combination
workpiece positioning/hold-down and anti-kickback device, taken
along line 19-19 of FIG. 17;
[0036] FIG. 20 is a top plan view, partly in section, of a modified
embodiment of the present invention;
[0037] FIG. 21 is cross-sectional view of the modified embodiment
of FIG. 20 taken along line 21-21 of FIG. 20;
[0038] FIG. 22 is a top plan view, partly in section of another
modified embodiment of the present invention; and
[0039] FIG. 23 is a perspective view of the combination workpiece
positioning/hold-down and anti-kickback device according to the
embodiment shown in FIG. 22.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] Referring to the drawings in detail, a combination workpiece
positioning/hold-down and anti-kickback device 10 according to the
present invention is designed for a use with a work table 12 having
a tabletop 14 with an upper surface 16 and opposite transverse
sides 18 and 20. As is conventional, a fence 22 is secured at one
edge of work table 12. During operation, a workpiece 24, such as a
piece of wood, is positioned on upper surface 16 and against fence
22. Then, a woodworking operation is performed by a woodworking
tool such as a saw, router 26 and the like, while workpiece 24 is
moved in the lengthwise direction 27 of work table 12, against
fence 22.
[0041] In order to press workpiece 24 against fence 22, combination
workpiece positioning/hold-down and anti-kickback device 10
includes a positioning member 28 having a main body 30 with a
generally oblong shape, and an arcuate cam surface 32 at one
shorter edge of main body 30 for engaging a side surface of
workpiece 24 on work table 12. Positioning member 28 can be made of
a plastic material, a Teflon (trademark) like material, or the
like. In accordance with the present invention, as will be
described in more detail below, main body 30 is oriented
substantially in a direction 34 transverse to lengthwise direction
27. Further, arcuate cam surface 32 has a curvature with an
increasing radius in a direction opposite to the direction 27 of
movement of workpiece 24 along work table 12 such that smaller
radius portions 32a of arcuate cam surface 32 extend closer toward
workpiece 24 than larger radius portions 32b of arcuate cam surface
32. This means that, as positioning member 28 is pivoted about a
fixed pivot pin, as will be described hereinafter, engagement with
smaller radius portions 32a provides a stronger biasing action.
[0042] A pivot pin 36 which is fixed to main body 30 at a side
opposite from arcuate cam surface 32, is pivotally mounted to an
adjustment device 38 for moving positioning member 28 relative to
workpiece 24. Specifically, adjustment device 38 includes a
lengthwise adjustment assembly 40 movable in lengthwise direction
27 for adjusting the position of positioning member 28 in
lengthwise direction 27, and a transverse adjustment assembly 42
movable in transverse direction 34 for adjusting the position of
positioning member 28 in transverse direction 34, with transverse
adjustment assembly 42 being movably connected to lengthwise
adjustment assembly 40.
[0043] Lengthwise adjustment assembly 40 includes a first guide
track 44 extending in lengthwise direction 27 and a second guide
track 46 extending in lengthwise direction 27, second guide track
46 being collinear with first guide track 44, with a gap 48 between
first and second guide tracks 44 and 46. Positioning member 28 is
located in gap 48. Each guide track 44 and 46 includes two spaced
apart and parallel grooves 50 and 52 therein, the purpose for which
will become apparent from the discussion hereinafter. Further, side
plates 54 are secured to sides of guide tracks 44 and 46 at
adjacent ends of guide tracks 44 and 46, with upper edges of side
plates 54 having short locking teeth 56 thereon.
[0044] Lengthwise adjustment assembly 40 further includes a guide
rail 58 mounted on top of guide tracks 44 and 46 and
interconnecting guide tracks 44 and 46. In this regard, guide rail
58 lies above gap 48, with pivot pin 36 being pivotally mounted in
a recess 60 at the underside of guide rail 58. In addition, guide
rail 58 includes a downwardly extending stop pin 62 which limits
the angular pivoting range of positioning member 28.
[0045] Guide rail 58 includes two spaced apart and parallel,
lengthwise extending rods 64 and 66 secured to an underside thereof
by countersunk screws 67 (FIG. 8), and which slidably extend within
grooves 50 and 52, respectively, to prevent transverse movement of
guide rail 58 relative to guide tracks 44 and 46.
[0046] Further, guide rail 58 includes side plates 68 at opposite
ends thereof, each having locking teeth 70 at the lower edge
thereof which engage with locking teeth 56 of side plates 54 of
first and second guide tracks 44 and 46, to prevent relative
lengthwise movement therebetween when guide rail 58 is clamped to
guide tracks 44 and 46, as will be described hereinafter.
[0047] In order to provide such clamping operation, a lengthwise
releasable locking device 72 is provided, which effectively
releasably locks lengthwise adjustment assembly 40 relative to work
table 12 at a desired location in lengthwise direction 27.
Specifically, lengthwise releasable locking device 72 includes two
releasable clamping devices 74 for releasably clamping guide rail
58 to first and second guide tracks 44 and 46 at a desired location
therealong.
[0048] As best shown in FIG. 8, each releasable clamping device 74
includes a bolt 76 extending through a vertically oriented hole 78
in each guide track 44 and 46. The lower end of hole 78 can have a
hexagonal recess 80 therein for receiving the hexagonal bolt head
76a. Guide rail 58 includes two aligned through slots 82 at
opposite ends thereof, each through slot 82 extending in lengthwise
direction 27. Each bolt 76 thereby extends through hole 78 and a
respective through slot 82, and then to a position above guide rail
58, where it threadedly receives a nut 84 thereon. A clamping head
86 is secured to nut 84.
[0049] Thus, as clamping head 86 is rotated, nut 84 is caused to
rotate, whereby clamping head 86 moves down in order to press guide
rail 58 onto guide tracks 44 and 46, and thereby releasably lock
guide rail 58 to guide tracks 44 and 46. In such condition, guide
rail 58 and guide tracks 44 and 46 form a unitary assembly.
[0050] With this arrangement, assuming that guide tracks 44 and 46
are fixed in position, as will be discussed hereinafter, guide rail
58 can move in lengthwise direction 27. Since positioning member 28
is pivotally mounted to guide rail 58, positioning member 28 is
also moved in lengthwise direction 27 for adjusting the position
thereof.
[0051] A coil spring 88 is connected between positioning member 28
and adjustment device 38 for biasing positioning member 28 with a
biasing force in a first pivot direction 90 about pivot pin 36 such
that arcuate cam surface 32 is biased in a direction opposite to
feed direction 27 of workpiece 24 and into engagement with the side
surface of workpiece 24.
[0052] In this regard, an eyelet 92 is secured to the side edge of
positioning member 28 which is opposite arcuate cam surface 32,
with one end of spring 88 secured to eyelet 92. The opposite end of
spring 88 is secured to a threaded rod 94 which forms part of a
variable tensioning device 96 for variably adjusting the biasing
force of spring 88. Rod 94 extends through an opening 98 in an
L-shaped bracket 100 which is secured to the side edge of guide
rail 58, and a wing nut 102 is threaded to the end of rod 94
extending out through opening 98. As a result, positioning member
28 is pivoted in pivot direction 90 about pivot pin 36 with a
biasing force which is variably adjustable by tightening or
loosening wing nut 102.
[0053] In order to move positioning member 28 in transverse
direction 34, that is, closer to or farther away from workpiece 24,
adjustment device 38 includes transverse adjustment assembly 42
which is movable in transverse direction 34. Transverse adjustment
assembly 42 includes a first abutment 104 in the form of an
L-shaped bracket fixed to the lower surface of first guide track 44
for engaging one transverse side 18 of work table 12 and a second
abutment 116 for engaging the opposite transverse side 20 of work
table 12.
[0054] In order to lock first and second abutments 104 and 116
against work table 12, and thereby releasably lock positioning
member 28 in a desired transverse position, a transverse release
locking device 105 includes an overcenter clamp 106 fixed to the
lower surface of second guide track 46, with overcenter clamp 106
having a handle 108 pivotally secured to a linkage 110 that is
slidably mounted to the lower surface of second guide track 46 by a
holder 112. A threaded rod 114 is threadedly secured to the end of
linkage 110, and second abutment 116 is secured to the opposite end
of threaded rod 114.
[0055] With this arrangement, threaded rod 114 is turned so as to
move second abutment 116 closer to or farther away from handle 108
in lengthwise direction 27. This is performed until abutments 104
and 116 loosely abut against transverse sides 18 and 20 of work
table 12. Then, handle 108 is pivoted to a closed position, thereby
moving threaded rod 114 away from it, whereby first and second
abutments 104 and 116 tightly engage tabletop 14. In this manner,
positioning member 28 can be moved toward or away from workpiece
24, and be secured in a desired transverse position.
[0056] In operation, the position of positioning member 28 in
lengthwise direction 27 is first adjusted by lengthwise adjustment
assembly 40. Thereafter, the position of positioning member 28 in
transverse direction 34 is adjusted by transverse adjustment
assembly 42. Wing nut 102 is then rotated to adjust the spring
biasing force.
[0057] When workpiece 24 is moved in feed direction 27, for
example, for a router operation, spring 88 rotates arcuate cam
surface 32 of positioning member 28 into engagement with the side
of workpiece 24 with a light spring tension. Thus, workpiece 24 is
pushed against fence 22 to obtain exact positioning of workpiece
24. It is to be pointed out that the material of positioning member
28 and the spring force on positioning member 28 do not damage
workpiece 24, even if workpiece 24 is made from a soft wood
material, such as pine.
[0058] As workpiece 24 is moved in the feed direction 27, there may
be a tendency for router 26 to impart a force to workpiece 24 which
tends to push it in a direction away from fence 22, that is, to
provide a kick-back. With the present invention, however, this
results in positioning member 28 being rotated further in pivot
direction 90. As a result, because of the curvature of arcuate cam
surface 32, there is a stronger force applied to workpiece 24,
which acts against such kick-back in order to prevent or minimize
the same. This occurs even through positioning member 28 is made of
a plastic material, a Teflon (trademark) like material, or the
like, and may be somewhat slippery.
[0059] In order to press workpiece 24 down from above, combination
workpiece positioning/hold-down and anti-kickback device 10
includes a hold-down member 128 having a main body 130 with a
generally oblong shape, and an arcuate cam surface 132 at one
shorter edge of main body 130 for engaging an upper surface of
workpiece 24 on work table 12. Hold-down member 128 can be made of
a plastic material, a Teflon (trademark) like material, or the
like. In accordance with the present invention, as will be
described in more detail below, main body 130 is oriented
substantially in a vertical direction 134 transverse to lengthwise
direction 27. Further, arcuate cam surface 132 has a curvature with
an increasing radius in a direction opposite to the direction 27 of
movement of workpiece 24 along work table 12 such that smaller
radius portions 132a of arcuate cam surface 132 extend closer
toward workpiece 24 than larger radius portions 132b of arcuate cam
surface 132.
[0060] A pivot pin 136 which is fixed to main body 130 at a side
opposite from arcuate cam surface 132, is pivotally mounted to an
adjustment device 138 for moving hold-down member 128 relative to
workpiece 24. Specifically, adjustment device 138 includes a
lengthwise adjustment assembly 140 movable in lengthwise direction
27 for adjusting the position of hold-down member 128 in lengthwise
direction 27, and a vertical adjustment assembly 142 movable in
vertical direction 134 for adjusting the position of hold-down
member 128 in vertical direction 134, with vertical adjustment
assembly 142 being movably connected to lengthwise adjustment
assembly 140.
[0061] Lengthwise adjustment assembly 140 includes a guide track
144 extending in lengthwise direction 27. Guide track 144 is formed
by a generally tubular member 145 of a square cross-section and
having a slot 147 running the length at the upper surface thereof.
Lengthwise adjustment assembly 140 further includes a guide rail
158 slidably mounted on top of guide track 144.
[0062] In order to provide such sliding movement and to also
provide a clamping operation, a lengthwise releasable locking
device 172 is provided, which effectively releasably locks
lengthwise adjustment assembly 140 relative to work table 12 at a
desired location in lengthwise direction 27. Specifically,
lengthwise releasable locking device 172 includes a releasable
clamping device 174 for releasably clamping guide rail 158 to guide
track 144 at a desired location therealong.
[0063] As best shown in FIG. 3, releasable clamping device 174
includes a bolt 176 extending through slot 147 and a hole 178 in
guide rail 158, with bolt head 176a being received in guide rail
144. The opposite end of bolt 176 extends into guide rail 158 where
it is engaged with a clamp 177 having a rotatable handle 179 (shown
in FIGS. 1, 2 and 5). When handle 179 is rotated in one direction,
bolt 176 is pulled up, so that bolt head 176a engages with guide
track 144 so as to releasably lock guide rail 158 to guide track
144. When handle 179 is rotated in the opposite direction, bolt 176
is lowered, thereby permitting sliding movement of guide rail 158
on guide track 144 to adjust the lengthwise position thereof.
[0064] In order to move hold-down member 128 in vertical direction
134, that is, closer to or farther away from workpiece 24,
adjustment device 138 includes vertical adjustment assembly 142
which is movable in vertical direction 134. Vertical adjustment
assembly 142 includes two vertically oriented rods 181 extending
upwardly from guide rail 158 in parallel, spaced apart relation. A
guide block 183 is slidably mounted along vertically oriented rods
181.
[0065] As best shown in FIG. 4, guide block 183 has two T-shaped
slots 185 extending in vertical direction 134. A vertical
releasable locking device 205 includes a releasable clamp 207
secured to guide block 183 for releasably engaging vertically
oriented rods 181. Specifically, a bolt 209 extends through each
T-shaped slot 185 such that the respective rod 181 is captured in
the T-shaped slot 185 between the bolt head 209a and guide block
183. A clamp head 211 threadedly receives the free end of bolt 209
extending through T-shaped slot 185. When clamp head 211 is
tightened, bolt head 209a clamps the respective rod 181 against
guide block 183 to releasably lock guide block 183 in a desired
vertical position. When clamp head 211 is loosened, bolt head 209a
no longer clamps the rod 181, so that guide block 183 is free to
move along rods 181.
[0066] A coil spring 188 is connected between hold-down member 128
and adjustment device 138 for biasing hold-down member 128 with a
biasing force in a first pivot direction 190 about pivot pin 136
such that arcuate cam surface 132 is biased in a direction opposite
to feed direction 27 of workpiece 24 and into engagement with the
upper surface of workpiece 24.
[0067] In this regard, an eyelet 192 is secured to a side edge of
hold-down member 128 which is transverse to arcuate cam surface
132, with one end of spring 188 secured to eyelet 192. The opposite
end of spring 188 is secured to a threaded rod 194 which forms part
of a variable tensioning device 196 for variably adjusting the
biasing force of spring 188. Rod 194 extends through an opening 198
in an L-shaped bracket 200 which is secured to guide block 183, and
a nut 202 is threaded to the end of rod 194 extending out through
opening 198. As a result, hold-down member 128 is pivoted in pivot
direction 190 about pivot pin 136 with a biasing force which is
variably adjustable by tightening or loosening nut 202.
[0068] In operation, the position of hold-down member 128 in
lengthwise direction 27 is first adjusted by lengthwise adjustment
assembly 140. Thereafter, the position of hold-down member 128 in
vertical direction 134 is adjusted by vertical adjustment assembly
142. Nut 202 is then rotated to adjust the spring biasing
force.
[0069] When workpiece 24 is moved in feed direction 27, for
example, for a router operation, spring 188 rotates arcuate cam
surface 132 of hold-down member 128 into engagement with the upper
surface of workpiece 24 with a light spring tension. Thus,
workpiece 24 is pushed down. It is to be pointed out that the
material of hold-down member 128 and the spring force on hold-down
member 128 do not damage workpiece 24, even if workpiece 24 is made
from a soft wood material, such as pine.
[0070] As workpiece 24 is moved in the feed direction 27, there may
be a tendency for router 26 to impart a force to workpiece 24 which
tends to push it in a direction opposite the feed direction 27,
that is, to provide a kick-back. With the present invention,
however, this results in hold-down member 128 being rotated further
in pivot direction 190. As a result, because of the curvature of
arcuate cam surface 132, there is a stronger force applied to
workpiece 24, which acts against such kick-back in order to prevent
or minimize the same. This occurs even through hold-down member 128
is made of a plastic material, a Teflon (trademark) like material,
or the like, and may be somewhat slippery.
[0071] Thus, in accordance with the present invention, the side and
upper surface of workpiece 24 are held or biased, while preventing
kick-back thereof. Further, positioning member 28 is adjustable in
lengthwise and transverse directions relative to workpiece 24,
while hold-down member 128 is adjustable in lengthwise and vertical
directions relative to workpiece 24. In addition, the biasing force
of the positioning or hold-down member against workpiece 24 is
variably adjustable.
[0072] FIGS. 10-12 illustrate a modified embodiment wherein the
locking teeth 56, 70 and the side plates are eliminated so as to
provide smooth mating (facing) surfaces for guide tracks 44, 46 and
guide rail 58. Locking of the members 46, 58 relative to each other
is achieved by providing a linear gear rack 150 in each of grooves
50 (of FIG. 1) of each of members 44, 46 and by providing a mating
linear gear rack section 160 in the upper clamping part 58 which
clamps against the lower gear rack 150. See FIG. 12.
[0073] Referring to FIGS. 10-12, the modified embodiment is
explained in more detail. As shown in FIGS. 10 and 11, a linear
gear rack, such as a spur gear rack manufactured by Boston Gear
(part No. L505-4) having a pitch of 24 teeth per inch and a width
of about 1/4 inch is mounted in mounting groove 164 of each of
members 44, 46. The linear gear rack 150 is stationary relative to
the respective guide tracks 44, 46. A clamping member 74, which
clamps upper guide rail 58 to lower guide rail 46 (see FIG. 12) is
provided for tightening the clamping between the upper and lower
guide rails 46, 58 and for mutually engaging the teeth of the lower
gear rack 150 with the teeth of the upper gear rack 160. The area
170 in FIG. 12 shows the mutually engaged teeth of the upper and
lower gear racks 160, 150, respectively. The clamping member 74 in
FIG. 12 is similar to the clamping arrangement of FIG. 8, and a
detailed description thereof is not given. To move the guide rails
58, 46 relative to each other, the clamping member 74 is loosened,
the upper guide rail 58 is lifted so as to bring the teeth of the
upper linear gear rack 160 out of engagement with the teeth of
lower linear gear rack 150, so that the parts 46, 58 can be moved
horizontally relative to each other. After proper location, the
clamp member 74 is tightened so as to bring the teeth of the gear
rack sections 150, 160 back into engagement with each other,
thereby locking member 58 relative to member 46.
[0074] The linear gear rack sections 150, 160 are maintained in
position by use of screws shown in FIG. 12. Other attachment could
be used, such as nails rivets, adhesives, etc.
[0075] The reference numerals in FIGS. 10-12 which are the same as
in FIGS. 1-9 represent the same or similar articles as in FIGS.
1-9.
[0076] As seen in FIG. 11, the lower gear rack section 150 extends
horizontally only from point A to point B so as to have a length L,
which is substantially shorter than the length of the upper linear
gear rack section 160. It is not necessary for the lower linear
gear rack section 150 to extend for the full length of the upper
gear rack section 160. As seen in the right hand side of FIG. 11,
the upper gear rack section has a length L2 which is much greater
than length L1 of the upper gear rack section.
[0077] As should be clear, the groove 50 shown in FIG. 1 is
rounded, whereas the groove for accepting the lower gear rack
section 150 is rectangular to accept the gear rack section.
Similarly, the upper groove in member 58 is made rectangular so as
to accept the upper gear rack section 160. A benefit of the
modified arrangement of FIGS. 10-12 is that the locking mechanism
is now internal and the user would be less likely to snag a sleeve
or other clothing or otherwise contact exposed sawtooth sections,
as is possible in the embodiment of FIGS. 1-9.
[0078] Referring now to FIGS. 13-19, wherein reference numerals
which are the same as in FIGS. 1-12 represent the same or similar
articles as in FIGS. 1-12, a modified embodiment of the combination
workpiece positioning and anti-kickback device 310 for a work table
12 is shown. In this alternative embodiment the lengthwise
adjustment assembly 40 includes first, second and third lengthwise
adjustment members 312, 314, 316. The first lengthwise adjustment
member 312 is disposed in a gap between the second and third
lengthwise adjustment members 314, 316. The second and third
lengthwise adjustment members are preferably hollow or have at
least an aperture therein such that at least a portion of the first
lengthwise adjustment member 312 is slidably received in each of
the second and third lengthwise adjustment members 314, 316.
[0079] Positioning member 28 is coupled to the first lengthwise
adjustment member 312 via a pivot pin 36. The position of the
positioning member 28 with respect to the work table 12 and
workpiece 24 is adjustable by changing the orientation of the first
lengthwise adjustment member 312 in relation to the second and
third lengthwise adjustment members 314, 316. That is, if the
positioning member 28 needs to be positioned with respect to the
work table 12 at a point which is closer to the second lengthwise
adjustment member 314, the first lengthwise adjustment member is
slidably engaged to a greater extent within the interior portion of
the second lengthwise adjusting member 314 and to a lesser extent
within the interior portion of the third lengthwise adjusting
member 316. Likewise, if the positioning member 28 needs to be
positioned with respect to the work table 12 at a position which is
closer to the third lengthwise adjustment member 316, the first
lengthwise adjustment member is slidably engaged to a greater
extent within the third lengthwise adjustment member 316 and to a
lesser extent within the interior portion of the second lengthwise
adjusting member.
[0080] The first lengthwise adjustment member 312 includes a
plurality of apertures 318 (preferably holes or notches) along at
least one side of its length. Coupled to each of the second and
third lengthwise adjustment members is a lengthwise releasable
locking device 72 which includes a locking pin 320 (see FIGS. 16
and 19) having a spring 322, which biases the locking pin 320 in
engagement with the first lengthwise adjustment member 312, and a
knob 324. As a result, when the first lengthwise adjustment member
312 is properly oriented within the second and third lengthwise
adjustment members 314, 316 such that the pin is aligned with
apertures 318, the locking pins 320 releasably engage the apertures
disposed on the first lengthwise adjustment member. The first
lengthwise adjustment member 312 is then prevented from movement
within the second and third lengthwise adjustment members 314,
316.
[0081] The combination workpiece positioning and anti-kickback
device of FIGS. 13-19 also includes a transverse adjustment
assembly 42. In this embodiment, the transverse adjustment assembly
42 includes transverse releasable locking devices 105 which include
first and second clamping devices 326 which are respectively
coupled to and near respective ends of the second and third
lengthwise adjustment members and corresponding ends of the work
table 12. In order to secure the transverse position of the
lengthwise adjustment assembly 40, the first and second clamping
devices 326, which preferably include a knob 328 having a threaded
member 330 are tightened. This secures the transverse position of
the lengthwise adjustment assembly on the work table.
[0082] In the alternative embodiment shown in FIGS. 13-19, the
device also includes a hold-down member 128 which provides a force
on a top surface of the workpiece 24 to ensure that the workpiece
remains in contact with the table top 14 of the work table 12. The
hold-down member includes a lengthwise adjustment assembly 140 and
a vertical adjustment assembly 142 as shown in FIG. 13. The
lengthwise adjustment assembly is similar to that which is shown in
FIG. 1 except that its longitudinal length is shorter due to the
configuration of the vertical adjustment assembly as explained
below.
[0083] Lengthwise adjustment assembly 140 includes a guide track
144 extending in lengthwise direction 27. Guide track 144 is formed
by a generally tubular member 145 of a square cross-section and
having a slot 147 running the length at the upper surface thereof.
Lengthwise adjustment assembly 140 further includes a guide rail
158 slidably mounted on top of guide track 144.
[0084] In order to provide sliding movement and to also provide a
clamping operation, a lengthwise releasable locking device 172 is
provided, which effectively releasably locks lengthwise adjustment
assembly 140 relative to work table 12 at a desired location in
lengthwise direction 27. Specifically, lengthwise releasable
locking device 172 includes a releasable clamping device 174 for
releasably clamping guide rail 158 to guide track 144 at a desired
location therealong.
[0085] As best shown in FIG. 15, releasable clamping device 174
includes a bolt 176 extending through slot 147 and a hole 178 in
guide rail 158, with bolt head 176a being received in guide rail
144. The opposite end of bolt 176 extends into guide rail 158 where
it is engaged with a clamp 177 having a rotatable handle 179. When
handle 179 is rotated in one direction, bolt 176 is pulled up, so
that bolt head 176a engages with guide track 144 so as to
releasably lock guide rail 158 to guide track 144. When handle 179
is rotated in the opposite direction, bolt 176 is lowered, thereby
permitting sliding movement of guide rail 158 on guide track 144 to
adjust the lengthwise position thereof.
[0086] The vertical adjustment assembly 142 includes a vertical
adjustment member 332 operatively coupled to the lengthwise
adjustment assembly 140. The vertical adjustment member 332 can be
integral and contiguous with the lengthwise adjustment assembly
140. The vertical adjustment member 332 is preferably oriented in
non-parallel relation with respect to the work table 12, and
preferably is perpendicular or substantially perpendicular to the
work table 12. The vertical adjustment member 332 includes a
longitudinal aperture 334 along its length which extends through
the hold-down member. The hold-down member 128 is coupled to a
mounting plate 336 by a pivot pin 136. The pivot pin is fixed to
the main body 130 of the hold-down member 128 at a side opposite
the arcuate cam surface. The hold-down member 128 is coupled to the
vertical adjustment member 332 by a clamping device 338 which
extends through the longitudinal aperture 334 of the vertical
adjustment member 332 and the mounting plate 336. In operation, the
clamping device 338 is loosened and its shaft is moved within the
longitudinal aperture 334 such that the height of the hold-down
member is fully adjustable in relation to the work table. When the
desired height of the hold-down member is attained, the clamping
device is tightened to secure the height thereof.
[0087] Referring now to FIGS. 20 and 21, wherein reference numerals
which are the same as in FIGS. 1-12 represent the same or similar
articles as in FIGS. 1-12, an alternative embodiment of the
lengthwise releasable locking device 172 and transverse releasable
locking device 105 of the combination workpiece positioning an
anti-kick back device is shown. The first lengthwise adjustment
member 312 slidably engages an interior portion of the second and
third lengthwise adjustment members 314, 316 as described in
connection with FIGS. 13-19. In this alternative embodiment
however, threaded rods 340 are extended through an end of each of
the second and third lengthwise adjustment members 314, 316. The
end of each of the second and third lengthwise adjustment members
314, 316 through which the threaded rods 340 extend is distal with
respect to the positioning member 28. The threaded rods include at
one end thereof a knob 342 which enables the threaded rod to be
rotated by hand. The opposite end of the threaded rod includes a
nut 344 which is fixed on the rod to indicate a maximum
displacement of the first lengthwise adjustment member 312 in each
lengthwise direction within the second and third lengthwise
adjustment members 314, 316.
[0088] The position of the first lengthwise adjustment member 312
with respect to the second and third lengthwise adjustment members
314, 316 is altered by rotating at least one of the knobs 342 of
the threaded rods 340 which extend within the interior portion of
the second and third lengthwise adjustment members and which engage
the first lengthwise adjustment member. The rotation of the
threaded rods alters the position of the first lengthwise
adjustment member and correspondingly the positioning member 28,
which is coupled thereto, with respect to the workpiece.
[0089] Referring now to FIGS. 22 and 23, wherein reference numerals
which are the same as in FIGS. 1-12 represent the same or similar
articles as in FIGS. 1-12, another alternative embodiment of the
lengthwise adjustment assembly is shown. In this embodiment the
work table 12 includes a groove 346 which is slidably engaged by a
rail 348 disposed on one side of a lengthwise adjustment member
350. The rail of the lengthwise adjustment member 350 slidably
moves within the groove 346 in a longitudinal direction 352, but is
prevented from substantial movement in the transverse direction
354. The groove 346 preferably includes a lip 356 (FIG. 23) at a
top portion thereof. A clamping device 358 having a block 360
disposed within the groove is coupledd to the lengthwise adjustment
member 350. When the clamping device is tightened, the block
engages the lip 356 of the groove 346. As a result, movement of
device is the lengthwise adjustment member 350 in the longitudinal
direction 352 is prevented.
[0090] Coupled to the lengthwise adjustment member 350 is a
transverse adjustment assembly 42 which is movable in a direction
354 transverse to the lengthwise direction 352. The transverse
adjustment assembly adjusts the position of the positioning member
28 in the transverse direction. The positioning member is
preferably coupled to one end of a transverse adjustment member
362. The coupling of the positioning member 28 to the transverse
adjustment member 362 via pivot pin 36 and the biasing of the
positioning member with spring 88 is similar to that previously
described and for brevity will not be repeated here.
[0091] The transverse adjustment member 362 preferably includes an
elongated aperture 364 which extends along the longitudinal length
of the transverse adjustment member 362 and therethrough. A
transverse releasable locking device 105 is included such as the
threaded rod, having a knob 368 at one end thereof, as shown in
FIG. 23. In this embodiment the lengthwise adjustment member 350
includes an aperture 368 for receiving an end of the threaded rod
366. The threaded rod extends through the elongated aperture 364 of
the transverse adjustment member 362 and engages the aperture 368
of the lengthwise adjustment member 350. When in a non-locked
position, the locking device 105 enables movement of the transverse
adjustment member while the threaded rod remains engaged in the
elongated aperture 364 and the aperture 368. When in the locked
position, the transverse releasable locking device 105 maintains
the position of the transverse adjustment member 362 with respect
to the lengthwise adjustment member 350 and, if the lengthwise
adjustment member 350 is secured to the work table 12 via clamping
device 358, the orientation of the positioning member 28 with
respect to the work table 12.
[0092] Having described a specific preferred embodiment of the
invention with reference to the accompanying drawings, it will be
appreciated that the present invention is not limited to that
precise embodiment and that various changes and modifications can
be effected therein by one of ordinary skill in the art without
departing from the scope or spirit of the invention as defined by
the appended claims.
* * * * *