Note: Descriptions are shown in the official language in which they were submitted.
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Backf~round of the Invention
The present invention relates to a miter gauge assembly, and more particularly, to a
self~ ning and self-adjusting miter gauge assembly that takes up dimensional clearances
between a miter gauge rod received within a miter gauge slot in a worktable for accurate miter
gauge positioning.
Conventional miter gauges are used in various powered tool equipment including table
saws, routers, sanders, band saws and the like. Typically, the miter gauge includes a miter
gauge rod that is pivotally attached to a miter gauge body having a semi-circular plate with
calibrations in degrees for accurately positioning the miter gauge body, including the semi-
circular calibrated plate, relative to the miter gauge rod. For mounting the miter gauge rod
relative to a worktable used in the aforementioned powered tool equipment, a miter gauge slot
is provided in an upper surface of a worktable for receiving the miter gauge rod.
It is well known that miter gauge rods and miter gauge slots vary in dimensional
clearances with respect to one another. For example, miter gauge rods of one manufacturer
may not fit the miter gauge slots in the worktables of other manufacturers of powered tool
equipment. Even for those manufacturers who manufacture their own miter gauges for use in
their own powered tool equipment, it is well known that typical dimensional variations
between a miter gauge rod and miter gauge slot create undesirable dimensional tolerances
which affect miter gauge positioning, particularly as wear and tear occur over time.
There have been attempts to solve this problem such as through the use of an
adjustable miter gauge bar, as shown in U.S. Patent No. 5,402,5~1, or an adjustable width
miter gauge bar, as shown in U.S. Patent No. 5,097,601. Despite the improvements
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associated with these devices, both of these and other prior art devices require continued and
repeated adjustment in constructions that also include a substantial number of parts. As will
be explained in the discussion that follows, the present invention
allows construction of a new and improved miter gauge assembly that
overcomes the aforementioned and other problems of the prior art. ~
The several objects and advantages of the present disclosure
include:
The provision of a new and improved miter gauge assembly that overcomes the
aforementioned and other problems of the prior art;
The provision of the aforementioned new and improved miter gauge assembly which
provides self-~ligning and self-adjustment of a miter gauge rod relative to a miter gauge slot
n a worktable;
The provision of the aforementioned new and improved miter gauge assembly which,
through its self-aligning and self-adjustment capabilities, takes up dimensional clearances
between a miter gauge rod and a miter gauge slot in the upper surface of a worlctable for
accurate miter gauge positioning;
The provision of the aforementioned new and improved miter gauge assembly in
which the miter gauge rod readily and quickly adapts to dimensional tolerances relative to a
miter gauge slot in an upper surface of a worktable;
The provision of the aforementioned new and improved miter gauge assembly which
includes adjustable spring ball elements that readily adapt to wear and tear of the miter gauge
rod relative to its associated miter gauge slot;
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The provision of the aforementioned new and improved miter gauge assembly which
is simple in construction and operation; uses a minimum number of parts; is relatively
economical to produce and maintain; is readily adaptable for initial and continuous adjustment
as desired; and is otherwise well adapted for the purposes intended.
Briefly stated, the self-aligning and self-adjusting miter gauge
assembly embodied in the present invention includes an elongated miter
gauge rod with at least two longitudinally spaced spring
ball elements that extend laterally from the elongated miter gauge rod for self-aligning and
self-adjustable engagement relative to adjacent surfaces of a complementary shaped miter
gauge slot, in order to take up dimensional clearance between the miter gauge rod and miter
gauge slot for accurate miter gauge positioning.
Each spring ball element may include a coil spring having a ball element attached to
one end. Each spring ball element also preferably includes an adjustable element to increase
or decrease the spring pressure of each associated spring ball element. Each adjustable
element is constructed to threadably engage an intemally t'nreaded passageway in the miter
gauge rod.
The spring ball element may include a spnng ball plunger as the adjustable element
that threadably engages intemally threaded passageway in the miter gauge rod.
The spring ball element may also include a coil spring having a ball attached to one
end with an extemally threaded element in the form of a set screw which engages the other
end of the coil spring, while threadably engaging the intemally threaded passageway, for
adjustment of the spring ball element.
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The elongated miter gauge rod preferably has a generally rectangular cross sectional
configuration having generally parallel longer upper and lower surface than generally parallel
opposite side edges. The miter gauge rod is mounted in a complementary shaped miter gauge
slot of a powered tool equipment worktable with the miter gauge slot including side surfaces
generally parallel to and in confronting relationship to the opposed side edges. Longitudinally
spaced threaded passageways extend laterally through the elongated miter gauge rod in
generally parallel relationship to its upper and lower surfaces and also provides openings in
each of the opposed side edges from each threaded passageway. An adjustable spring ball
element is mounted in each of the threaded passage~ays and includes an associated threaded
element for engaging the adjustable spring ball element while being in threaded engagement
with an associated threaded passageway. Each adjustable spring ball element, including the
threaded element, cooperates to move an associated adjustable spring ball element in self-
aligning and self-adjusting engagement with one of the opposed side surfaces of the miter
gauge slot in order to take up dimensional clearances between the miter gauge rod and miter
gauge slot for accurate miter gauge positioning.
Embodiments of the invention will now be described with reference
to the accompanying drawings, wherein,
Figure 1 is a top plan view of the miter gauge assembly embodying
the present invention that is mounted with respect to a miter gauge
slot in a powered tool equipment worktable;
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Figure 2 is a perspective view of the self-aligning and self-adjusting miter gauge
assembly that is constructed in accordance with the teachings of the present invention;
Figure 3 is an enlarged sectional view illustrating a spring ball plunger that serves as
one type of spring ball element used in conjunction with a miter gauge rod;
Figure 4 is an enlarged sectional view of another type of spring ball element, with a
coil spring having a ball bearing at one end and a set screw at the other end, for association
with a miler gauge rod.
Corresponding reference nurnerals will be used throughout the several figures of the
drawings.
Description of the Preferred l~;mbodiments
The following detailed description illustrates embodiments of the
invention by way of example and not by way of limitation. This
description will clearly enable one skilled in the art to make and
use the invention, and describes several embodiments, adaptations, variations, alternatives and
uses of the invention, including what I presently believe is the best mode of carrying out the
invention.
The self-aligning and self-adjusting miter gauge assembly 1
includes a miter gauge rod 3 having a miter gauge body 5 at one end. The miter gauge rod 3
is adapted to be received within a complementary shaped miter gauge slot 7 of a powered tool
equipment worktable 9. The various types of power tool equipment with which miter gauge
assemblies are used include table saws, routers, sanders, band saws, and the like.
As best illustrated in Figure 2 of the drawings, the self-aligning and self-adjusting
miter gauge assembly 1 is constructed to enable the miter gauge body 5 to be pivotally
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mounted to the miter gauge rod 3. Thus, as the threadable miter gauge knob l l is unscrewed,
enabling a lower face 13 of the knob I I to be moved out of engagement relative to the
elongated curvilinear surfaces 15 on opposite sides of the curvilinear slot 17, the miter gauge
body ~ can be pivotally adjusted relative to the miter gauge rod 3. In order to provide for
precise adjustments of the miter gauge body 5 relative to the miter gauge rod ~, the miter
gauge body 5 includes a semi-circular plate 17 that is calibrated in degrees. This permits
appropriate positioning of the miter gauge body ~ and associated calibrated semi-circular plate
17 relative to a pointed indicator l 9 mounted on a miter gauge indicator block 21 attached to
one end of the miter gauge rod 3. Following desired positioning, the knob l l is re-tightened.
All of the foregoing described components of the miter gauge assembly l are well-
known in the art and provide background understanding of the environment in which the self-
aligning and self-adjusting miter gauge assembly 1 is used.
The self-aligning and self-adjusting miter gauge assembly 1
includes at least two longitudinally spaced spring ball elements 23,
23 which extend laterally from the elongated miter gauge rod 3 for
self-aligning and self-adjustable engagement relative to adjacent
surfaces of a complementary shaped miter gauge slot 7, as
shown in Figure l, in order to take up dimensional clearances between the miter gauge rod 3
and the miter gauge rod 7, for accurate miter gauge positioning.
As shown in Figures 2-4 of the drawings, the elongated miter gauge rod 3 is of
generally rectangular cross sectional configuration having generally parallel longer upper and
lower surfaces 25, 25 than generally parallel opposed side edges 27, 27. The miter gauge slot
7 includes side surfaces 29, 29 tllat are generally parallel to and in confronting relationship to
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the opposed side edges 27, 27 of the miter gauge rod 3. A pair of longitudinally spaced
threaded passageways 31, 31 extend through the elongated miter gauge rod 3 in generally
parallel relationship to the upper and lower surfaces 25, 25 and also provide openings 33,33
in each of the opposed side edges 27 from each threaded passageway 31. The self-aligning
and self-adjusting miter gauge assembly 1 further includes an adjustable spring ball element
that is mounted in each of the longitudinally spaced threaded passageways 31,31. Each such
spring ball element is also selectively adjustable for increasing or decreasing the spring
pressure of its associated spring ball element.
Several different types of adjustable spring ball elements may be used. One such
adjustable spring ball element is shown in Figure 3 of the drawings and comprises a spring
ball plunger 35 that threadably engages an internally threaded and laterally extending
passageway 33. The spring ball plunger 35 includes a screwdriver slot 37 (or other equivalent
driving elements such as a hexagon or square shape) at one end and an elongated
longitudinally extending opening 39 at an opposite end for receiving a coil spring 41 and
associated ball 43. The spring ball plunger 35 is swaged or deformed at the outer end of the
elongated longitudinally extending opening 39 in order to retain a ball 43 in the relative
position illustrated in Figure 3 of the drawings. This prevents disassociation of the ball and its
associated spring 41 from the spring ball plunger 35.
It is important to note that the ball 43 extends laterally outwardly beyond the spring
ball plunger 35, as well as beyond one of the opposed side edges 27 of the miter gauge rod 3,
in order to enable the ball 43 to engage one of the side surfaces 29 of the miter gauge slot 7.
Since a predetermined amount of spring pressure is consistently applied through the coil
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spring 41 to the ball 43, the longitudinally spaced pair of spring ball elements 43 are capable
of engaging one adjacent side surface 29 of the miter gauge slot 7 for self-aligning and self-
adjustable engagement within a predetermined range. This self-aligning and self-adjustable
engagement further take up dimensional clearances between the miter gauge rod 3 and the
miter gauge slot 7 for accurate miter gauge positioning. It will be appreciated that the spring
pressure of the coil spring 41 may be increased or decreased by threadably engaging or
disengaging the externally threaded spring ball plunger 35 relative to its associated
longitudinally extending threaded passageway. This can be easily accomplished by a
screwdriver (not shown) engaging the screwdriver slot 37 for selective adjustment of the
spring pressure in the coil spring 41.
A second type of adjustable spring ball element is shown in Figure 4 of the drawings
and includes an externally threaded ferrule 45 in the form of a set screw having a screwdriver
slot 47 at one end. The externally threaded ferrule or set screw 45 engages a coil spring 51 at
its opposite end which is associated with a ball 53. In order to retain the ball in its relative
position shown in Figure 4, the side edge 27, through which the ball 53 extends, is deformed
or swaged in order to hold the ball in its relative position as illustrated in Figure 4. Selective
adjustment of the spring pressure of the coil spring 51 can be accomplished simply by
inserting a screwdriver blade in the screwdriver slot 47 and tightening the externally threaded
ferrule or set screw 45 to increase the spring pressure or by loosening the externally threaded
fe-rule or set screw 45 relative to the internally threaded passageway 31 for decreasing the
spring pressure in the coil spring 51.
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.
In the use of the adjustable spring ball elements disclosed in Figures 3 or 4 of the
drawings or in other equivalent embodiments, it will be appreciated that the at least two
spaced spring ball elements, including their associated threaded elcments that engage the
internally threaded passageways, enable the longitudinally spaced adjustable spring ball
elements to be positioned in self-aligning and self-adjusting engagement with one of the
opposed side surfaces of the miter gauge slot in order to take up dimensional clearances
between the miter gauge rod and miter gauge slot for accurate miter gauge positioning. The
longitudinally spaced adjustable spring ball elements not only readily and quickly adapt to
dimensional tolerances between the miter gauge rod and miter gauge slot, but also readily
adapt to wear and tear of the miter gauge rod relative to its associated miter gauge slot.
Should adjustment be required, selective adjustment of the adjustable spring ball elements
may be accomplished, in the manner described above. In addition, adjusting the spring ball
elements forces the miter gauge rod against an opposite side of the miter gauge slot to
maintain alignment. Adjusting the spring ball elements also makes continuous adjustment for
variations in width of any given miter gauge slot. Moreover, there is an ease of engagement
of the miter gauge rod into the miter gauge slot by using the spring ball elements rather than
prior art fixed adjustment techniques.
In view of the above, it will be seen that the several objects and advantages of the
present invention have been achieved and other advantageous results have been obtained.
As various changes could be made in the above constructions without departing from
the scope of the invention, it is intended that all matter contained in the above description or
1~
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shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting
sense.
