Note: Descriptions are shown in the official language in which they were submitted.
5903-166CN CA 02224134 1997-12-09
FITTING FOR PLAIN END PIPES
BACKGROUND OF THE INVENTION
The present invention relates to pipe fittings,
and more particularly, to pipe fittings for joining plain
end pipes.
Several techniques have been developed for joining
pipes made of metal. Ferrous pipe has typically been welded
or threaded in the field. The latter are mated with
threaded pipe fittings or couplings (both hereinafter
referred to collectively as "fittings"). However, the use
of threaded fittings in ferrous piping adds significantly to
the labor costs of installing such systems. Copper tubing
installs more quickly than ferrous pipe as the cut lengths
of copper can simply be slip-mated with appropriate fittings
and then soldered. However, copper is quite expensive in
material cost compared to ferrous pipe.
- A number of systems have been developed for plain
end ferrous piping that do not require threading or welding
of the pipe end(s). Crimping systems are known in which
crimpable fittings can be used to join small diameters of
the lightest Schedule 5 steel piping. Other types of
mechanical, compression type fittings are known which
sealingly mate with the exterior ends of grooved piping.
These systems may or may not employ a tubular insert in the
CA 02224134 1997-12-09
pipe ends and may or may not require grooving or other
machining of the pipe end(s).
BRIEF SUM~ARY OF THE INVENTION
In a first aspect, the present invention is a pipe
fitting that includes a fixture member having a hollow
interior, an outer surface and a channel, the channel
extending outwardly from the hollow interior through the
outer surface of the fixture member on one outer side of the
fixture member and defining a pipe opening through the outer
surface of the fixture member. The opening and the channel
are shaped to encircle a plain end of a pipe and the opening
and the channel have a common central axis. The pipe
fitting also includes an engagement member having a cutting
surface exposed outside of the fixture member and a threaded
attachment member. The threaded attachment member extends
outwardly from the outer surface of the fixture member on
the one outer side of the fixture member to the engagement
_ member and connects the engagement member with the fixture
member. The threaded attachment member has a central axis
that extends sequentially away from the engagement member,
through the outer surface, into the fixture member and
generally toward the central axis of the channel and the
opening.
In a second aspect, the present invention is a
method of using a fitting of the present invention to secure
a plain end pipe within the fitting.
-- 2
CA 02224134 1997-12-09
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The foregoing summary, as well as the following
detailed description of preferred embodiments of the
invention, will be better understood when read in
conjunction with the appended drawings. For the purpose of
illustrating the invention, there is shown in the drawings,
which are diagrammatic, embodiments which are presently
preferred. It should be understood, however, that the
invention is not limited to the precise arrangements and
instrumentalities shown. In the drawings:
Fig. l is a partially broken front view of a
fitting in accordance with the present invention;
Fig. 2 is a right side view of the fitting of Fig.
l;
Fig. 3 is cross-section of the fitting fixture
member;
Fig. 4 is a broken-away right side view of the
fixture member in Fig. 3;
Fig. 5 is a front view of an engagement member;
- Fig. 6 is a side view of an engagement member;
Fig. 7 is a broken-away front view of the fitting
in cross section, showing a preferred type of gasket
situated in an annular recess and an engagement member in an
initial position to receive a plain end pipe;
Fig. 8 is a front view of the preferred gasket;
Fig. 9 is a cross-sectional view taken along lines
9-9 of Fig. 8;
CA 02224134 1997-12-09
Fig. 10 is a broken away, front view of an
alternative embodiment fitting which has a permanently
attached threaded attachment member and a threaded nut;
Fig. ll is a broken-away front view in cross
section of the fitting of Figs. 1 and 7, showing a pipe
inserted into the channel of the fixture member with the
engagement member in an initial position during a method of
securing a pipe in the fitting;
Fig. 12 is a broken-away front view of the fitting
in cross section, showing the engagement member at an
engaged position during movement of the engagement member
toward the fixture member;
Fig. 13 is a greatly enlarged view of the area
indicated in Fig. 12, showing the cutting engagement of the
engagement member and accumulated material; and
Fig. 14 is a side view of the fitting with two
pipes secured therein and a sprinkler head connected within
a supplemental channel, showing one intended application of
the fitting.
-
DETAILED DESCRIPTION OF THE INVENTION
Certain terminology is used in the following
description for convenience only and is not limiting. The
words "inner and "outer" refer to directions toward and away
from, respectively, the center of a fitting and/or the
center of a fixture member. The terminology includes the
CA 02224l34 l997-l2-09
words above specifically mentioned, derivatives thereof and
words of similar import.
Referring now to the drawings in detail, wherein
like numerals are used to indicate like elements throughout,
there is shown in Figs. 1, 7, 11, 12 and 14, an exemplary
preferred embodiment of the pipe fitting 10 of the present
invention for one or more plain end pipes 11 in the form of
a Tee. The pipe fitting 10 is primarily comprised of a
fixture member 12, an engagement member 14 and threaded
attachment member 16 extending outwardly from the fixture
member 12 to the engagement member 14 and connecting the
engagement member 14 with the fixture member 12.
Referring to Figs. 1-4, the fixture member 12 has
a hollow interior 18, an outer surface 20 and a channel 22.
Preferably, the fixture member 12 iS constructed of a single
main body 13 that has a generally cylindrical shape and
includes a tubular wall 15. However, it is within the scope
of the present invention to construct the fixture member 12
of two or more pieces assembled together (not shown) and/or
to construct the fixture member of another appropriate
- shape, such as for example, a tubular polygonal cylinder
(not shown).
Referring to Figs. 2-4, the channel 22 iS defined
by a first inner circumferential surface 23 of the fixture
member 12. The channel 22 extends outwardly from the hollow
interior 18 through the outer surface 20 of the fixture
member 12 on at least one outer side 24 of the fixture
member 12 and defines a pipe opening 26 through the outer
surface 20 of the fixture member 12. The pipe opening 26
CA 02224l34 l997-l2-09
and the channel 22 are shaped to encircle a plain end of a
pipe 11 and the opening 26 and the channel 22 have a common
central axis 28. Preferably, as shown in Figs. 2 and 4, the
pipe opening 26 and the channel 22 have a circular shape
with a common diametric value and are both sized to fit
about a particular standard sized pipe 11 with a slip fit.
Referring to Figs. 3 and 4, preferably, the first
inner circumferential surface 23 defining the channel 22
includes an outer section 30 preferably having a constant
inner diameter do and extending inwardly from the pipe
opening 26, and an inner section 32 preferably having a
constant inner diameter diand extending inwardly from the
outer section 30 to at least a central axis 34 of the
fixture member 12. The inner diameter do of the outer
section 30 iS greater than the inner diameter di of the
inner section 32 SO that the fixture member 12 includes a
radial surface 36 disposed between the inner section 32 and
the outer section 30. The radial surface 36 faces toward
the pipe opening 26 and provides a seating surface for the
end of a pipe 11 inserted into the fixture member 12, as
- discussed in detail below. However, it is within the scope
of the present invention to construct the channel 22 SO that
the inner circumferential surface 23 has a constant inner
diameter throughout or varies in other ways, for example, by
having an inner diameter that decreases toward the center of
the fixture member 12.
The exemplary preferred fixture member 12 has a
second pipe opening 40 through the outer surface 20 of the
fixture member 12 on a second outer side 25 of the fixture
CA 02224l34 l997-l2-09
me~,ber 12 shaped to encircle a plain end of a pipe 11. The
channel 22 extends between the first pipe opening 26 and the
second pipe opening 40 and the openings 26 and 40 and the
channel 22 all have a common central axis 28. The first
inner circumferential surface 23 defining the channel 22
further includes a second outer section 42 extending
inwardly from the second pipe opening 40 to the inner
section 32 and having a constant inner diameter do2 that is
greater than the inner diameter di of the inner section 32,
so that the fixture member 12 further includes a second
radial surface 44 disposed between the inner section 32 and
the second outer section 42. The second radial surface 44
faces toward the second pipe opening 40 and provides a
second seating surface 46 for the end of a second pipe 11
inserted into the fixture member 12, as discussed below.
Referring to Figs. 3 and 4, preferably, the
fixture member 12 further includes at least one threaded
bore 48A extending through the outer surface 20 on the one
outer side 24 of the fixture member 12. In a preferred
embodiment, the fixture member 12 includes a second threaded
- bore 48B extending through the outer surface 20 on the
second outer side 25 of the fixture member 12. The threaded
bores 48A, 48B enable attachment of one embodiment of the
threaded engagement member 16 to the fixture member 12, as
discussed in detail below. Preferably, the threaded bores
48A, 48B each have a thread that is sized to engage a
standard threaded bolt. Each threaded bore 48 has a central
axis 50A and 50B, respectively, that converges generally
with the central axis 28 of the channel 22 and the pipe
CA 02224134 1997-12-09
openings 26, 40. Preferably, the central axes 50A, 50B of
the threaded bores 48A, 48B, respectively, form an acute
angle 01 with respect to the central axis 28 of the channel
22 and the pipe openings 26, 40 that is greater than O
5 degrees and less than 45 degrees, desirably lO degrees or
less and, preferably, about 5 degrees or less.
Referring to Figs. 1, 3 and 4, the fixture member
12 preferably includes two attachment projections 52A, 52B
which each extend from the main body 13 of the fixture
member 12. Preferably, the attachment projections 52A, 52B
each have a semi-cylindrical shape and are substantially
aligned with each other on the outer surface 20 of the
fixture member 12. The threaded bores 48A, 48B are each
disposed within a separate one of the attachment projections
15 52A, 52B, respectively, and extend at least partially, and
preferably completely, therethrough.
By having the attachment projections 52A, 52B, the
main body 13 of the fixture member 12 can be constructed
with a tubular wall 15 that has a lesser thickness than is
20 required if the threaded bores 48A, 48B are disposed within
- the main body 13 of the fixture member 12. The attachment
projections 52A, 52B therefore minimize the amount of
material necessary to construct the fixture member 12.
However, it is within the scope of the present invention to
25 construct the fixture member 12 without the attachment
projections 52A, 52B and to dispose the threaded bores 48A,
48B within a more uniformly tubular main body of a fixture
member.
CA 02224134 1997-12-09
Referring to Figs. 3 and 7, the fixture member 12
also includes at least one annular recess 56 extending
circumferentially into the fixture member 12 from the inner
surface 23 of the channel 22. In the depicted preferred
embodiment of the fitting 10 in which the fixture member 12
has first and second pipe openings 26 and 40, respectively,
the fixture member 12 includes two annular recesses 56A, 56B
which are each disposed proximal to a separate one of the
pipe openings 26, 40, respectively. Each annular recess 56
has a width wr that is constant about the circumference of
the inner surface 23 and is sized and shaped to enable a
cylindrical gasket to be disposed therein.
Referring to Figs. 1-3, preferably, the fixture
member 12 further includes two annular projections 58A, 58B
which each extend outwardly from a remainder of the main
body 13 of the fixture member 12 and extend
circumferentially about the main body 13.
According to the invention, the fixture member 12
also includes at least one gasket 60 disposed within an
annular recess 56A. Referring to Figs. 7-9, when disposed
- within the annular recess 56A, a portion of the gasket 60
extends from the recess 56A and into the channel 22. In the
depicted preferred embodiment of the fitting 10 in which the
fixture member 12 has two annular recesses 56A, 56B, the
fixture member 12 includes a second gasket 60 in the
remaining annular recess 56B.
Preferably, as shown in Figs. 8 and 9, each gasket
60 is constructed of a substantially cylindrical outer ring
62 having an inner surface 64 and an annular projection 66
g
CA 02224l34 l997-l2-09
extending radially inwardly from the inner surface 64 of the
outer ring 62. The projection 66 has a wedge-shaped cross-
section and is deformable in an axial direction. Each
gasket 60 iS assembled into a separate annular recess 56A
and 56B SO that the projection 66 deforms toward the central
axis 34 of the fixture member 12 and therefore, each gasket
60 iS oriented in opposite directions with respect to the
fixture member 12.
Referring to Figs. 11, 12 and 14, when a pipe 11
is inserted into the channel 22 and through the gasket 60, a
portion of the projection 66 becomes deformed and juxtaposed
with the inner surface 64 of the outer ring 62, providing a
firm seal between the gasket 60 and the pipe 11.
Referring to Figs. 1 and 3, the fixture member 12
preferably further includes a supplemental channel 68
extending from the hollow interior 16 through the outer
surface 20 of the fixture member 12. The supplemental
channel 68 iS defined by a second inner circumferential
surface 70 of the fixture member 12, with the second inner
circumferential surface 70 being threaded in this
- embodiment. The supplemental channel 68 defines a
supplemental opening 72 through the outer surface 20 of the
fixture member 12. Further, the supplemental channel 68
connects with the channel 22 so that flow communication is
established between one or more pipes 11 inserted into the
channel 22 and a threaded member engaged with the
supplemental channel 68, such as, for example, a sprinkler
head as shown in Fig. 13 and as described below or a drop
connected with such head.
- 10 -
CA 02224134 1997-12-09
Further, the fixture member 12 includes a third,
supplemental channel 68 that extends through a mounting
projection 69 such that a supplemental opening 72 is
disposed at the outer end 71 of the mounting projection 69.
The mounting projection 69 includes a threaded inner surface
70 and a circular mounting surface 73 which surrounds the
supplemental opening 72 and provides a surface against which
a shoulder of a sprinkler head or other fluid manipulating
device may be abutted.
Although the preferred depicted embodiment of the
fitting 10 is a "tee", it is possible to adapt the present
invention to other types of fittings (none of which are
shown): straight couplings (two pipe openings), bent
couplings (elbows), crosses (four pipe openings) or as an
"adapter" with one plain end pipe opening and a threaded
opening or flange end. In any of these alternative
constructions, a channel is provided which extends through
the fixture member between or among the openings of the
fixture member.
Preferably, the fixture member 12 is constructed
- as a hollow, machined, one-piece casting of ductile iron.
However, it is within the scope of the present invention to
construct the fixture member 12 by other techniques, such as
forging or extruding and to machine utilizing any other
finishing techniques necessary to complete the fixture
member 12. Furthermore, it is within the scope of the
present invention to construct the fixture member 12 of
another appropriate material, such as, for example, steel,
copper, aluminum or a polymeric material or a combination of
CA 02224l34 l997-l2-09
materials, e.g. polymeric body with metal inserts,
particularly for use of the invention with pipe of other
material(s). The gaskets are preferably commercially
available gaskets made of rubber or a comparable polymeric
material.
Referring to Figs. 1, 2, 5 and 6, the engagement
member 14 includes a cutting surface 74 that is exposed
outside of the fixture member 12 when the pipe fitting 10 is
assembled as described below. Preferably, the engagement
member 14 iS a plate 76 having a radiused side 78 forming
the cutting surface 74, with the radiused side 78 and
cutting surface 74 having at least one cutting edge 80.
Furthermore, the plate 76 preferably has a partially
circular contour with the center of the radius rc of the
radiused side 78 being located off of the plate 76 SO that
the radiused side 78 iS generally concave. However, is
within the scope of the present invention to construct the
engagement member 14 of any other appropriate shape that
enables the engagement member 14 to perform the intended
function as described in detail below.
- Preferably, as shown in Figs. 5 and 6, the
engagement member 14 includes a through hole 82 which has a
central axis 83 that is substantially parallel to the
radiused side 78 of the plate 76. The through hole 82
2 5 enables attachment of the engagement member 14 with the
threaded attachment member 16, as described below. However,
it is within the scope of the present invention to construct
the engagement member 14 without the through hole 82 and to
include a separate member such as a bracket (not shown)
CA 02224134 1997-12-09
attached to the engagement member 14 and connectable with
the threaded attachment member 16.
Preferably, the engagement member 14 is
constructed by being stamped from a plate of low carbon
steel, with the through hole 80 being pierced prior to
blanking the outer contour of the plate 76. However, it is
within the scope of the present invention to construct the
engagement member 14 of another material, such as, for
example, powdered metal, or to manufacture the engagement
member 14 by another process, such as, for example, casting
or machining.
Referring to Figs. 1, 2, 11, 12 and 14, the
threaded attachment member 16 is preferably a commercially
available bolt having a shaft 84, threads 85, a central axis
88 and a head section 86 that is disposed at one end of the
shaft 84.
In an alternative embodiment fitting 10' shown in
Fig. 10, the threaded attachment member 16' is a threaded
rod 84' without a head section, which is fixedly attached to
the fixture member 12' by suitable means such as, for
_ example, welding or threading. The alternative embodiment
fitting 10' further includes a threaded nut 90 that is
threadably engageable with the attachment member 16' and the
fixture member 12 does not include a threaded bore 48. The
engagement member 14 and the threaded nut 90 are assembled
to the threaded attachment member 16' so that the attachment
member 16' extends through the through hole 82 of the
engagement member 14 and the engagement member 14 is
CA 02224l34 l997-l2-09
disposed between the threaded nut 9O and the fixture member 12'.
Referring to Figs. 1, 2, and 11, the components of
the fitting lO are preferably assembled together either
prior to inserting a pipe 11 within the pipe opening 26.
When the fitting lO is assembled, the threaded attachment
member 16 extends outwardly from the outer surface 20 of the
fixture member 12 on the one outer side 24 of the fixture
member 12 to the engagement member 14 and connects the
engagement member 14 with the fixture member 12. In the
preferred embodiment, the threaded attachment member 16 or
16' extends through the through hole 82 of the engagement
member 14 and the head section 86 of the attachment member
16, or nut 9O used with member 16', iS disposed against a
side of the plate 76 of the engagement member 14 that faces
generally away from the fixture member 12.
Referring to Figs. lO and 11, in either embodiment
lO or lO' of the assembled fitting, the central axis 88 of
the attachment member 16 or 16' extends sequentially away
from the engagement member 14, through the outer surface 20
of the fixture member 12 or 12', into the fixture member 12
- or 12' and generally toward the central axis 28 of the
channel 22 and the pipe openings 26 and 40. Preferably, as
shown in Figs. lO and 11, the central axis 88 of the
threaded attachment member 16 converges generally toward the
central axis 28 of the channel 22 at acute angle 01 with
respect to the central axis 28 of the channel.
In a preferred embodiment of the pipe fitting lO
of the present invention shown in Fig. 1, the fitting lO
further comprises a second engagement member 14 and a second
- 14 -
CA 02224l34 l997-l2-09
threaded attachment member 16 extending to the second
engagement member 14 from a location on the outer surface 20
of the fixture member 12 proximal to the second pipe opening
40. Preferably, when the second engagement member 14 and the
second threaded attachment member 16 are assembled to the
fixture member 12, the second engagement member 14 and the
second attachment member 16 are each in an orientation with
respect to the fixture member 12 that mirrors the
orientations, described above, of the engagement member 14
and the attachment member 16, respectively, proximal the
first pipe opening 26 about the central axis 34 of the
fixture member 12.
Referring to Figs. 11-13, the present invention
further includes a method of securing at least one plain end
96 of a pipe 11 within a fitting 10 or 10'. First, as shown
in Fig. 11, a plain end 96 of a pipe ll is inserted into the
pipe opening 24 of the fixture member 12 and through gasket
60. The cutting surface 74 of the engagement member 14 is
positioned facing an outer surface 98 of the pipe.
Preferably, the pipe 11 is inserted a sufficient distance
- into the fixture member 12 SO that an end surface 97 of the
pipe 11 is abuts against the seating surface 38 of the
fixture member 12.
The engagement member 14 is then moved toward the
fixture member 12 along the central axis 88 of the threaded
attachment member 16. The central axis 99 of the pipe 11 is
substantially co-linear with the central axis 28 of the
channel 22 of the fixture member 12, so that the central
axis 88 of the attachment member 14 converges toward the
- 15 -
CA 02224l34 l997-l2-09
central axis 99 of the pipe and its outer surface 98 at an
acute angle 02 with respect to the central axis 99 of the
pipe 11, which is preferably equal to 01~ the angle between
the axis 88 of the attachment member 16 and the axis 28 of
the channel 22. Due to the convergence of the central axis
88 of the attachment member 16 with respect to the central
axis 99 of the pipe 11, the engagement member 14 moves in
angled path toward the fixture member 12 which causes the
cutting surface 74 of the engagement member 14 to first
contact, and then progressively cuttingly engage, the outer
surface 98 of the pipe 11. In other words, as the
engagement member 14 moves toward the fixture member 12, the
cutting surface 74 of the fixture member 12 is scraped along
and progressively digs further into the outer surface 98 of
the pipe 11, as shown in Fig. 13.
In fitting lO, the engagement member 14 iS moved
or biased toward the fixture member 12 by rotating the bolt
16 within the threaded bore 48 SO that the bolt 16 advances
into the threaded bore 48. The head section 86 of the bolt
16 pushes the engagement member 14 toward the fixture member
12 and at least initially overcomes any resistance to
cutting into the material of the outer surface 98 of the
pipe 11. In the alternative embodiment of the pipe fitting
lO' shown in Fig. lO, the engagement member 14 iS biased
toward the fixture member 12 by rotating the nut 9O about
the rod 84 of the attachment member 16', and the nut 9O
performs the same function with respect to the engagement
member 14 as the head 86 of the attachment member 16 in the
preferred embodiment.
CA 02224134 1997-12-09
Referring particularly to Fig. 13, as the cutting
surface 74 of the engagement member 14 engages the outer
surface 98 of the pipe 11, material M is removed from the
outer surface 98 of the pipe 11. The removed material M is
accumulated on the outer surface 98 between the engagement
member 14 and the fixture member 12. The accumulated
material M and the cut-away surface 95 of the pipe 11 that
abuts the front surface 75 of the engagement member 14 near
the cutting edge 80 form an interference fit between the
pipe 11 and the engagement member 14. The interference fit
resists the tendency of the pipe 11 to move along the pipe
central axis 99 in a direction away from the fitting 10,
such a tendency being caused by, for example, the pressure
of fluid within the pipe 11.
Since the engagement member 14 contacts the outer
surface 98 of the pipe 11 on only one side of the central
axis 99 of the pipe 11, the engagement member 14 also pushes
a section of the outer surface 98 of the pipe 11 that is on
the opposite side of the axis 99 against the inner surface
23 of the channel 22 of the fixture member 12. Any tendency
- of the pipe 11 to move along the axis of the pipe and out of
the channel 22 of the fixture member 12 will give rise to a
frictional force that is parallel to the central axis 99 of
the pipe 11 and exerted in a direction opposite the
direction of movement. Thus, the engagement member 14 also
provides an additional friction fit between the pipe 11 and
the channel 22 of the fixture member 12 that assists the
securement of the pipe 11 within the fitting 10.
- 17 -
CA 02224134 1997-12-09
When utilizing the preferred embodiment of the
pipe fitting 10 that includes a fixture member 12 having a
second pipe opening 40, a second pipe 11 is secured within
the fitting 10 by the same method as described above.
Finally, the pipe 11 may be removed from the pipe
fitting 10 by moving the engagement member 14 away from the
fixture member 12 a sufficient distance so that the cutting
surface 74 of the engagement member 14 disengages from the
outer surface 98 of the pipe 11. With either embodiment, a
prying force may then have to be applied to the surface 75
of the engagement member 14 by using, for example, a
pressure bar, so that the cutting surface 74 of the
engagement member 14 is dislodged from the outer surface 98
of the pipe 11. The fitting 10 may then be reused with
another pipe 11 in the same manner and may be used
repeatedly for any number of applications.
Referring to Fig. 14, one particular intended
application of the pipe fitting 10 and the method of the
present invention is for use in sprinkler systems. The pipe
fitting 10 may be used to couple one or more pipes to a
- sprinkler head 100, as shown in Fig. 15, or to a threaded
pipe or drop (not shown) connected to a sprinkler head. The
sprinkler head 100 is connected with the fitting 10 by
threading a tubular stem portion of the head 100 into the
supplemental channel 68.
As discussed above, the pipe fittings 10, 10' of
the present invention have a number of advantages over
previous pipe fittings for use with plain end pipes. The
pipe fittings 10, 10' can be used with a plain end pipe 11
- 18 -
CA 02224134 1997-12-09
without the necessity of machining the end section 96 of the
pipe 11 to enable attachment within the fittings 10, 10'.
The pipe 11 is easily secured within the fittings 10, 10' by
merely turning a threaded bolt or nut, which requires the
use of only common hand tools and is therefore less
expensive to use than fittings that require welders,
crimpers or other special machines to enable connection of
the pipe with the fitting. Furthermore, the pipes 11 can be
easily disconnected from the fitting, again by using only
common hand tools, and the fitting 10, 10' is reusable for
any number of further applications.
It will be appreciated by those skilled in the art
that changes could be made to the embodiments described
above without departing from the broad inventive concept
thereof. It is understood, therefore, that this invention
is not limited to the particular embodiments disclosed, but
it is intended to cover modifications within the spirit and
scope of the present invention as defined by the appended
claims.
- 19 -
