Note: Descriptions are shown in the official language in which they were submitted.
CA 02593699 2013-01-14
CLAMPING DEVICE
REFERENCE TO RELATED APPLICATION
This application claims benefit of priority to U.S. Provisional application
serial number 60/830,617, filed
July 14,2906 and entitled "CLAMPING DEVICE".
FIELD OF THE INVENTION
1.0 This invention relates in general to devices and methods for securing
plate-like work pieces during
machining.
DESCRIPTION OF THE RELATED ART
The precision machining, of large work pieces, such as plate-like work pieces,
requires the use of a wide
array of machine tools such as gauges, templates, cooling systems, hydraulic
clamps, and drill-sets. These
= tools are expensive to acquire and maintain.
=
Large work pieces, such as steel plates, are typically manufactured using a
large gantry milling machine. In
one conventional system, steel plates are stacked on a milling table and
clamped at regular locations along
their aligned peripheries so not to interfere with the machining process,
which may involve one or more
milling and/or drilling steps. A gantry is configured to move along tracks
that extend parallel to the work
pieces, such that the gantry provides an overhead tool head to support for one
or more machining tools.
The gantry may be adjusted along the length of the work pieces, and the tool
head may be adjusted along x,
y and z axes relative to the work pieces to machine the work pieces. As the
process proceeds, there is a
tendency of bulging between the work pieces as material shavings force
themselves in between the work
pieces. This problem is more pronounced as the size of the work pieces
increase, the amount of machining
that is done on the work pieces and as the distance from the clamped
peripheral edges increases. For
example, the problem may be come acute when the machining step occurs in a
central region of these work
pieces.
What is needed is a novel approach to clamping such work pieces. =
SUMMARY OF THE INVENTION
The following presents a simplified summary of the general inventive concept
herein to provide a basic
understanding of some aspects of the invention. This summary is not an
extensive overview of the
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invention. It is not intended to restrict key or critical elements of the
invention or to delineate the scope or
the invention beyond that explicitly or implicitly described by the following
description and claims.
In one aspect, there is provided a device for securing work pieces comprising
a first body and a second
body, the first body including at least two opposed body sections, a
resiliently compressible biasing portion
arranged to allow an outer diameter of the first body to contract allowing
passage within a plurality of
= aligned openings in said work pieces, a restraining portion for
preventing the first body from expanding
beyond an operable expanded orientation, the first body including a segment of
an engagement portion
near a first end thereof, the engagement portion including an operative
surface to engage an outer surface
on a first outer work piece, the first body having a second end and a threaded
inner support extending
between the opposed body sections the second body being operable to engage an
outer surface on a second
outer work piece, the second body including a passage to receive a threaded
member to engage the threaded
inner support, the threaded member being rotationally operational to draw the
first body toward the second
body.
In some embodiments, the engagement portion includes a peripheral lateral lip.
Furthermore, in preferred
embodiments, the operative surface of the peripheral lateral lip is inclined
at its outermost edge toward the
second end.
- 20 In Some embodiments, ihe resiliently compressible biasing portion is a
spring.
In some embodiments, one or both of the body sections includes a formation to
engage the resiliently
compressible biasing portion and in preferred embodiments the fonnation
includes a first cavity in each of
the body sections and near the first end.
In some embodiments, the first body includes a second cavity in each of the
body sections and near the
second end to receive the threaded inner support. In preferred embodiments,
the threaded inner support has
a pair of end sections, each of which extend into the second cavity in a
corresponding body section, with a
threaded passage being aligned with the first passage.
-In some embodiments, the threaded member has a length corresponding to a
depth of the plurality of
openings. Furthermore, in some embodiments, the threaded member is a bolt.
In some embodiments, the second body includes a cap having a hole to receive
the threaded member.
In some embodiments, the first body includes a second cavity to receive the
threaded inner support.
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In sonic embodiments, the restraining, portion is located along the first body
at a location between the
biasing portion and the threaded inner support. In some embodiments, the first
body further includes an
outer peripheral groove to receive the restraining portion. In preferred
embodiments, the restraining portion
= , is an o-ring.
= In some embodiments, the threaded inner support is a nut or a bobbin.
In another aspect, there is provided a device for clamping a group of work
pieces together comprising a
first body having a peripheral lateral surface, the first body being laterally
dimensioned to pass through an
inner path formed by aligned passages in the group of work pieces, the first
body having a first end region
with a circumferential laterally outwardly extending flange, the first body
having at least two body sections,
each having a corresponding portion of the peripheral lateral surface and a
portion of the flange, a biasing
portion positioned between the first body sections for laterally outwardly
biasing the first body sections and
a limiting portion for limiting movement of the first body sections beyond an
expanded orientation, the first
body being movable between a compressed orientation in which the flange fits
within the inner path, to the
expanded orientation in which the flange extends laterally beyond the inner
path to engage an outer surface
on a first outer one of the group of work pieces, the first body having a
second end region opposite the first
end region with a central opening therein, an anchor portion extending between
the body sections near the
second end region, the anchor portion having a first threaded passage and
exposed to the central opening; a
second body to lie against a second one of the group of work pieces, the
second body having a second
passage which is alignable with the first threaded passage; a threaded member
arranged to engage the first
threaded passage and the second passage and to extend between the first and
second bodies, the threaded
member rotatably operable to draw the first and second bodies together against
the first and second outer
work pieces.
In some embodiments, the first body is provided as being generally cylindrical
in shape.
In some embodiments, at least one of the body sections including a first inner
formation to receive the
biasing portion.
In some embodiments, the first inner formation includes a first cylindrical
cavity. Furthermore, in some
embodiments, the body sections include a pair of second inner formations to
receive the anchor portion. In
some embodiments, the second inner formations each include a second
cylindrical cavity.
In some embodiments, the outer peripheral surface includes a recess with the
limiting portion including an
o-ring to be located in the recess.
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In some embodiments, the flange has a beveled peripheral edge region.
In some embodiments, there is provided an undercut formation between the
peripheral lateral surface and
the circumferential laterally outwardly extending flange.
In some embodiments, the peripheral lateral surface has a taper extending
between the first end region and
= the second end region.
In another aspect, there is provided a device for clamping a plurality of work
pieces together comprising a
body having a first portion of a first diameter and a second portion of a
second diameter, the first portion =
having a circumferential laterally outwardly extending flange to engage an
outer surface of a first work
piece, the first portion further having at least two body sections, each
having a corresponding portion of the
flange, a biasing portion positioned between the body sections for laterally
outwardly biasing the body
sections and a restraining portion for preventing the body sections from
expanding beyond an operable
second orientation, the body being operable in a first orientation with a
first diameter to permit the flange to
pass through a plurality of aligned passages in said work pieces and the
second orientation with a second
diameter to present the flange to extend beyond the aligned passages and
engage an outer surface of a
second work piece, the first and second portions having a threadable member to
be rotatable to draw the
first and second bodies together.
In yet another aspect, thereis provided a kit for clamping a group of work
pieces together comprising a first
= body having a peripheral lateral surface, the first body being laterally
dimensioned to pass through an inner
= path formed by aligned passages in the group of work pieces, the first
body having a first end region with a
circumferential laterally outwardly extending flange, the first body having at
least two body sections, each
having a corresponding portion of the peripheral lateral surface and a portion
of the flange, a biasing
portion positioned between the first body sections for laterally outwardly
biasing the first body sections and
a restraining portion for preventing the first bOdy sections from expanding
beyond an expanded orientation,
the first body being movable from a compressed orientation in which the flange
fits within the inner path,
. to the expanded orientation in which the flange extends laterally beyond the
inner Path to engage an outer
surface on a first outer One of the group of work pieces, the first body
having a second end region opposite
the first end region with a central opening therein, an anchor portion
extending between the body sections
near the first second end region, the anchor portion having a first threaded
passage and exposed to the
central opening; a second body to lie against a second one of the group of
work pieces, the second body
having a second passage which is alignable with the first threaded passage; a
plurality threaded members of
various lengths each operable to be arranged to engage the first threaded
passage and the second passage
and to extend between the first and second bodies, each of the threaded
members rotatably operable to draw
the first and second bodies together against the first and second outer work
pieces, an instructional manual
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instructing an user how to assemble the first and second bodies, how to choose
the appropriate length of the
threaded member and how to disengage the first and second bodies from the work
pieces.
=
In still yet another aspect, there is provided a method of machining plate-
like work pieces comprising:
- assembling individual plate-like work pieces into a stack;
- clamping an outer region of the plate-like work pieces in a manner so as not
interfere with a
subsequent machining operation;
- drilling at least one hole through the stack;
- providing a device for securing the plate-like work pieces, the device
comprising a first body and
= 10 a second body, the first body including at least two
opposed body sections, a resiliently
compressible biasing portion arranged to allow an outer diameter of the first
body to contract so as
to allow passage with in the at least one hole and a restraining portion for
preventing the first body
=
from expanding beyond an operable expanded orientation, the first body
including a segment of an
engagement portion near a first end thereof, the engagement portion including
an operative surface
for engaging a first outer surface on a first plate-like work piece of the
stack, the first body having
a second end and a threaded inner support extending between the opposed body
sections, the
second body being operable to engage a second outer surface on another plate-
like work piece
Opposing the first plate-like work piece of the stack, the second body
including a passage to
receive a threaded member to engage the threaded inner support, the threaded
member being
rotationally operational to draw the first body toward the second body;
- manipulating the device to laterally a contracted orientation and inserting
the first body with the
At least one hole such that the engagement portion extends beyond the first
outer surface of the
first plate-like work piece of the stack;
- rotating the threadable member to draw the first body and the second body
together so as to
engage the engagement portion with the first outer surface and the second body
with the second
outer surface;
- machining the stack;
- releasing the device from the stack; and
- disassembling the plate-like work pieces from the stack.
In some embodiments, the method includes installing the restraining portion at
a predetermined location on
the first body. In some embodiments, the method includes installing the
restraining portion as an o-ring in
= a predetermined recess on the first body.
In another aspect, there is provided a temporary securing device for plate-
like work pieces comprising a
first body including at least two body sections maintained in an operable
aligned configuration against a
laterally outward bias by a limiting portion and a second body having a second
passage;
=
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=
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the least two body sections each having a first end region and a second end
region;
the second body portion having a cross-sectional dimension greater than the
diameter of an opening
= located in the work piece;
the at least two body sections each having a peripheral lateral surface and an
inner surface, the inner
. 5 surface defining a portion of a central cavity with a central
opening located near the second end region;
= the first and second body portions being provided in an arrangement so as
to align the second passage
and the central opening for receiving respectively therethrough and therein a
threaded member for engaging
a first threaded passage located in an anchor portion operably maintained
between the at least two body
sections near the second end region;
a compressible biasing portion being operably maintained between the
respective inner surfaces near .
= the first end regions of the at least two body sections and being
provided so as to laterally outwardly bias
the first end regions; the at least two body sections each having an
engagement portion located near the first
= end;
the engagement portion having an operative surface to engage an outer surface
on a first outer work
piece;
the threaded member being rotationally operational so as to draw the at least
two body sections toward
the second body and to outwardly laterally move the first end regions in the
direction of the bias.
= In some embodiments, the engagement portion includes a peripheral lateral
lip inclined at its outermost
edge toward the second end region.
In some embodiments, the limiting portion is provided as art a-ring seated in
a recess located along the first
= body at a location between the biasing portion and the threaded inner
support and is provided for
preventing the at least two body sections from expanding beyond an operable
expanded orientation.
BRIEF DESCRIPTION OF THE DRAWINGS
,Several preferred embodiments of the present invention will be provided, by
way of examples only, with
reference to the appended drawings, wherein,
. 30
Figure I is a sectional view of a device for clamping a_group of work pieces;
Figure 2 is a top plan view of a machining installation for a stack of work
pieces of figure I;
=
Figure 3 is a side view of the stack of figure 2 in a measuring step;
= Figures 4 and 5 are perspective side views, of the device of figure 1 in
alternative orientations;
=
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Figures 6, 7 and 8 are fragmentary perspective views of the stack of figure 2
and the device of
figure I in different operative positions;
= 5 Figure 8a is a side view of a portion of the device of figure 1 in
an operative position according to
figure 8;
=
Figure 9 is a top plan view of a machining installation of figure 2 with a
plurality of devices of
figure i in an operative orientation;
. Figures 10, it and 12 are fragmentary perspective views of the
stack of figure 2 and the device of
figure 1 in still further different operative positions; and
Figure 13 is a side view of a kit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
It should be understood that the invention is not limited in its application
to the details of construction and
the arrangement of components set forth in the following description or
illustrated in the drawings. The
invention is capable of other embodiments and of being practiced or of being
carried out in various ways. =
Also, it is to be understood that the phraseology and terminology used herein
is for the purpose of
description and should not be regarded as limiting. The use of "including,"
"comprising," or "having" and
variations thereof herein is meant to encompass the item listed thereafter and
equivalents thereof as well as
additional items. Unless limited otherwise, the terms "connected," "coupled,"
and "mounted," and
variations thereof herein are used broadly and encompass direct and indirect
connections, couplings, and
mountings. In addition, the terms "connected" and "coupled" and variations
thereof are not restricted to
physical or mechanietil connections or couplings. Furthermore, and as
described in subsequent paragraphs,
the specific mechanical configurations illustrated in the drawings are
intended to exemplify embodiments
of the invention. However, other alternative mechanical configurations are
possible which are considered
to be within the teachings of the instant disclosure. Furthermore, unless
otherwise indicated, the term "or"
is to be considered Inclusive.
Referring to the figures 1 and 2, there is provided a device 10 for clamping a
group of work pieces 12
together. An example of such group (or stack 14 as in this case) of work
pieces is shown In figure 3 and in
an operative position on a gantry milling machine 16 as shown in figure 2.
Figure 3 shows, in dashed lines,
.a number of aligned passages 18 in the work pieces of the stack 14.
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The device 10 has a first body 20 with a peripheral lateral surface 22. As
shown in figures 4 and 7, the first
body 20 is laterally dimensioned to pass through an inner path 24 formed by
the aligned passages 18.
Referring to figure I, the first body 20 has a first end region 26 with a
circumferential laterally outwardly
extending flange 28. The first body 20 also has at least two body sections 30,
each bearing a corresponding
portion of the peripheral lateral surface and a portion of the flange 28. A
biasing portion 32 is positioned
between the first body sections 30 for laterally outwardly biasing them.
As will be described below, the first body 20 is movable between a compressed
orientation, as shown in
figure 7, in which the flange fits within. the inner path 24, and an expanded
orientation, as shown in figure
8, in which the flange 28 extends laterally beyond the inner path 24 to engage
an outer surface 38 on a first
outer one of the group of work pieces 40. The first body also has a relaxed
orientation as shown in figure
1, in which it is expanded still further beyond its expanded orientation.
Referring figure 4, the first body 20 has a second end region 42 opposite the
first end region 26 with a
central opening 44 therein. An anchor portion shown in figure 5 at 46 extends
between the body sections
30 near the second end region 42. In this ease, the anchor portion 46 has a
first threaded passage 48 and is
exposed to the central opening 44.
=
As can be seen in a number of the figures, such as figures 1 and 5, the device
10 is also provided with a
= 20 second body 50 to lie against a second one of the group of
work pieces 52 (figure 8) in this case on an outer
surface 54. The second body 50 has a second passage 56 which is alignable with
the first threaded passage
48. A threaded member 58 is arranged to engage the first threaded-passage 48
and the second passage 56
and to extend between the first and second bodies 20, 50 respectively. In this
case the threaded member 58
is rotatably operable, with the help of a rotary tool shown at 60 in figure 6,
to draw the first and second
bodies 20, 50 together against the first and second outer work pieces 4.0, 52.
Other configurations and/or
tools may be employed, if desired, to drive the threaded member 58.
Furthermore, other configurations
may be available in which the first and or second body 20, 50 are
correspondingly engaged with the first
and second outer work pieces 40, 52 in different orientations. For instance,
the second body 50 may
engage the outer surface of' the second work piece at a location distal to the
inner path, or may engage an
upper inner surface facing the inner path.
As shown in figure 1, the first body 20 is generally cylindrical in shape
although the first body 20 may have
other shapes and configurations, such as for instance, an oval or square cross
section. As best illustrated in
=
figure 7, the peripheral lateral surface 22 of the body has a taper 64 that
extends between the first end =
region 26 and the second end region 42 or toward the second end region 42.
This taper 64 enhances the
effect of the biasing portion 32 to bias the first body sections 20 to a fully
expanded orientation and/or to
extend the flange 28 laterally beyond the inner path 24 of the outer surface
38 on the first outer one of the
=
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group of work pieces 40. Alternatively the first body 20 may have a peripheral
lateral surface 22 of the
= body that is not tapered. For example, the peripheral lateral surface 22
may be provided with relatively
consistent or varying diameter between the first end region toward and second
end region.
As illustrated in figures 6, 7, 8 and 8a, at least one, in this case two, of
the body sections 30 includes a first
inner formation 66 to receive the biasing portion 32. In this case, the first
inner formation 66 is provided
by a first cylindrical cavity 68, but may be provided in other forms such as,
for example, a projection. The
biasing portion 32 is, in this case, a spring member 70, though other
resilient elements may also be used in
some cases, as desired, such as for instance a rubber plug,
The body sections 30 include a pair of second inner formations 72 to receive
the anchor portion 46. The
. second inner formations 72 each include a second cylindrical cavity 74. As
shown in dashed lines in Figure
5, the anchor 46 may be a bobbin 76 or nut or alternatively may be integrally
formed with one or both of
the body-sections 30.
As shown in figures 4 and 5, the device further includes a limiting portion 78
for limiting the movement of '
the body sections 30 beyond the expanded orientation. In this case the
limiting portion 78 is an o ring 80
but for example, may be in some other form, such as a tension band. En this
case, the outer peripheral
surface 22 includes a recess 82 to accommodate the limiting portion 78, though
other arrangements may be
utilized to operatively associate the limiting portion 78 with the body
sections.
As shown in figure 8a, the flange 28 has a beveled peripheral edge region 84
to assist the entry of the
device 10 into the inner path 24. The flange 28 further includes an undercut
formation 88 adjacent
peripheral lateral surface 22 to aid in "biting" into the outer surface 38 of
the first outer one of the group of
work pieces 40. The device 10 may also be provided with other formations other
then the undercut
formation, or in some other cases, without such undercut formation,
As shown in figure 13, the device 10 may be provided in the form of a kit 92
with a selection of parts
according to the device and configured to be useful for one or more specific
installations. For instance, the =
kit 92 may include a number of different length threaded members 94 as shown
In figure 13, each threaded
member being appropriate for a different stack height. The kit 92 may thus
inClude a set of instructions on
the steps for selecting the appropriate threaded member. The kit 92, may in
some cases not include the
threaded member, thusenabling the user to obtain the threaded member from a
separate source.
The device 10 may thus be used in the following manner. First, the user
assembles individual plate-like
work pieces into the stack 14, and clamps an outer region 96 of the plate-like
work pieces 12 in a manner
which will not interfere with a subsequent machining operation. The user then
drills at least one hole or
=
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passage through the stack, and measures the height of the stack to determine
the appropriate length of
threaded member required.
The user then assembles the device with the first body 20, the second body 50
and the threaded member 58.
.= 50. In this case, the threaded member 58 is selected with a length
appropriate for the overall thickness of
the stack 14 or the overall thickness of the aligned passages 18 therein, as
need be.
The user manipulates the device 10 to the compressed orientation in order to
fit within the aligned passages
18, as shown in figures 6 and 7.
The user passes the device through the aligned passages 18 until the first
body extends beyond the first
outer plate work piece 40 shown at to engage the first contact surface 38
thereon, as shown in figure 8. The
user aligns the second body 50 with the aligned passages 18 and against the
second contact surface 54 on
the second outer plate work piece-52.
The user thus rotates the threadable member 58, such as by way of the tool 60,
to draw the first and second
bodies 20, 50 together to secure the stack.
The user may then repeat this process for as many devices as needed in the
stacked work pieces. This may
involve installing a first device in a first location (as for example shown at
98 in figure 9) on the stack and
then subsequently carrying out a number of machining steps at a predetermined
vicinity of the first location
and then installing a second device at a second location (as for example shown
at 100 in figure 9) and
= repeating the process.
=
Alternatively, the user may predrill a number of strategic locations on the
stack and then pre-install a
device at each of the strategic locations so that all the following machining
steps, such as the boring of a
= hole in the stack, may-be carried out in a corresponding succession of
machining steps.
In this case., for this particular use of the device 10 (among other
possibilities uses thereof) the materials
used in the formation of the threaded member 58 and the first and second
bodies 20, 50 should be sufficient
to withstand the necessary loads thereon to offset the drive forces which are
otherwise applying force to the
shavings against the inner surface of the aligned holes, which would otherwise
cause the stack 14 to bulge
or delaininate.
When the machining operation is complete, the user rotates the threaded member
58 to release the device
10 from the stack 14. To do this, the user displaces the first body 20 out of
the aligned passages 18 as
shown in figure II. The user may then disassemble the plate-like work pieces
from the stack.
QM-TL/CD4 10
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CA 02593699 2013-01-14
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While device is discussed with reference to holes formed in work pieces, the
latter may be configured in
. other ways to accept the device, such as by way of slots, gaps, inner
corners and the like. In this case, the
device may be provided with other features to allow it to secure and clamp the
work pieces together, so that
the work piece has two or more opposing outer termini against which the first
body can act in its expanded =
.5 orientation to engage the work piece. While the device and method herein
are discussed with respect to an
inner path formed by the aligned passages in the work pieces, there may be
some instances where the
passages may not be aligned but may be of other configurations, such as
offset, while still enabling a =
version of the device to be used successfully to clamp the work pieces. The
inner passages may also be of
different dimensions. For instance, the outer plate members may have
relatively smaller passages while the
adjacent inner plate members may have larger passages.
While the present invention has been described for what are presently
considered the preferred
embodiments, the invention is not so limited. To the contrary, the invention
is intended to cover various
modifications and equivalent arrangements included within the spirit and scope
of the appended claims.
The scope of the following claims is to be accorded the broadest
interpretation so as to encompass all such
= modifications and equivalent structures and functions.
=
=
=
=
=
=
= = =
=
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QM-TH/CDA 11
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