U.S. patent application number 13/166058 was filed with the patent office on 2011-11-03 for method of forming a pipe fitting.
This patent application is currently assigned to Charlotte Pipe and Foundry Company. Invention is credited to Eric Wayne Lewis, Julie Starnes Parker.
Application Number | 20110266714 13/166058 |
Document ID | / |
Family ID | 34272520 |
Filed Date | 2011-11-03 |
United States Patent
Application |
20110266714 |
Kind Code |
A1 |
Lewis; Eric Wayne ; et
al. |
November 3, 2011 |
METHOD OF FORMING A PIPE FITTING
Abstract
A pipe fitting includes a polymeric body molded into and fixedly
connected to a metallic body, so that the metallic body extends
around the polymeric body. The polymeric body extends around and is
contiguous with a passageway of the pipe fitting, and at least
partially defines a first opening of the passageway that is for
being mated to a polymeric pipe. The metallic body extends around
and is contiguous with the passageway, and at least partially
defines a second opening of the passageway that is for being mated
to a metallic pipe.
Inventors: |
Lewis; Eric Wayne;
(Charlotte, NC) ; Parker; Julie Starnes; (Waxhaw,
NC) |
Assignee: |
Charlotte Pipe and Foundry
Company
Charlotte
NC
|
Family ID: |
34272520 |
Appl. No.: |
13/166058 |
Filed: |
June 22, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12387541 |
May 4, 2009 |
7988204 |
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13166058 |
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10923227 |
Aug 20, 2004 |
7527302 |
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12387541 |
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10923227 |
Aug 20, 2004 |
7527302 |
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10923227 |
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60496808 |
Aug 21, 2003 |
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Current U.S.
Class: |
264/267 |
Current CPC
Class: |
F16L 47/24 20130101;
Y10T 29/4943 20150115; B21K 1/16 20130101 |
Class at
Publication: |
264/267 |
International
Class: |
B29C 45/14 20060101
B29C045/14 |
Claims
1. A method of forming a pipe fitting, comprising: providing a
first body that extends around a passageway and defines at least
two openings to the passageway; mating at least one mold to the
first body, including inserting the mold into the passageway, so
that a chamber is defined between the first body and the mold, with
the first body extending around the chamber and the chamber
extending around the mold, and the mold engaging the first body so
that: the chamber has: a first end that is proximate a first
opening of the openings to the passageway, and a second end that is
located at an interposed position that is within the passageway,
between the first opening and a second opening of the openings of
the passageway, and distant from the second opening of the
passageway, and the mold substantially isolates the chamber from
the portion of the passageway that is between the interposed
position and the second opening of the passageway; molding a second
body in the chamber, so that the second body is formed in and
fixedly connected to the first body, the second body extends around
the mold, and the second body is at least substantially absent from
the portion of the passageway that is between the interposed
position and the second opening of the passageway; and then
separating the first body and the mold, and not separating the
second body from the first body.
2. A method according to claim 1, wherein the molding is injection
molding that includes injecting melted polymeric material into the
chamber.
3. A method according to claim 2, wherein the injecting includes
injecting the polymeric material through a hole which extends
through a sidewall of the first body.
4. A method according to claim 2, wherein the hole is positioned
between the first body's two openings to the passageway, and the
hole is distant from each of the first body's two openings to the
passageway.
5. A method according to claim 2, wherein the injecting includes
injecting the polymeric material through a gate of a jig, and the
method further comprises: placing the first body in the jig prior
to the molding; and removing the pipe fitting from the jig after
the molding.
6. A method according to claim 4, wherein: the injecting includes
injecting the polymeric material through a hole which extends
through a sidewall of the first body, and the placing includes
aligning the hole and the gate.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a division, and claims the
benefit, of co-pending U.S. patent application Ser. No. 12/387,541,
filed May 4, 2009, entitled "A PIPE FITTING FOR CONNECTING BETWEEN
A METAL PIECE OF PLUMBING AND A POLYMER PIECE OF PLUMBING," which
is a continuation and division, and claims the benefit, of U.S.
patent application Ser. No. 10/923,227, filed Aug. 20, 2004,
entitled "PIPE FITTING AND ASSOCIATED METHODS AND APPARATUS", now
U.S. Pat. No. 7,527,302, which claims the benefit of Provisional
Application 60/496,808, which was filed Aug. 21, 2003, each
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] One aspect of the present invention relates to a pipe
fitting for connecting between dissimilar pipes, or the like, and,
more particularly, for connecting between metallic and polymeric
pipes, or the like.
[0003] It is common for substances to flow between metallic and
polymeric pipes that are connected by a pipe fitting. As a more
specific example, water is often supplied from an upstream metallic
pipe to a downstream polymeric pipe that is the inlet of a plumbing
fixture or appliance, such as a faucet or the like. It is critical
for this type of pipe fitting to remain watertight, often for very
many years. Nonetheless, it is common for some of these pipe
fittings to occasionally fail, since they are typically exposed to
many cycles of stress caused by variations in the pressure and/or
temperature of the water being supplied.
[0004] A known pipe fitting for connecting between metallic and
polymeric pipes is formed by separately manufacturing generally
cylindrical polymeric and metallic bodies, and then connecting the
bodies to one another. The polymeric body is inserted into an
annular opening of the metallic body, and then the annular edge of
the opening is bent inward (e.g., crimped) to hold the polymeric
body in the metallic body. For this known pipe fitting, the
polymeric body extends around a passageway of the pipe fitting and
defines a first opening to the passageway, and the first opening is
for being mated to the polymeric pipe. In addition, the metallic
body extends around the polymeric body and defines a second opening
to the passageway, and the second opening is for being mated to the
metallic pipe. These pipe fittings have been known to fail at the
crimp, because the crimping can weaken the metallic body.
[0005] Accordingly, there is a need in the industry for improved
pipe fittings for connecting between metallic and polymeric
pipes.
BRIEF SUMMARY OF SOME ASPECTS OF THE INVENTION
[0006] Aspects of the present invention include the provision of an
improved pipe fitting that is capable of connecting between pieces
of plumbing such as, but not limited to, metallic and polymeric
pipes, and the provision of methods and apparatus for making pipe
fittings.
[0007] In accordance with one aspect of the present invention, a
composite pipe fitting includes a polymeric body that is molded to
and fixedly connected to a metallic body. It is preferred for at
least a portion of the polymeric body to be molded into the
metallic body such that the metallic body extends around the
polymeric body. The polymeric body extends around and is contiguous
with a passageway of the pipe fitting. The polymeric body also at
least partially defines a forward opening of the passageway that is
for being mated to a piece of plumbing such as, but not limited to,
a polymeric pipe. The metallic body at least partially defines a
rearward opening of the passageway that is for being mated to a
piece of plumbing such as, but not limited to, a metallic pipe. It
is preferred the metallic body to extend around and be contiguous
with the passageway.
[0008] In accordance with one aspect of the present invention,
restrictions in relative movement between the metallic and
polymeric bodies are advantageously facilitated by virtue of
contact therebetween. For example, it is preferred for at least one
protrusion of one of the bodies to be mated with at least one
shoulder, cavity or hole of the other body in a manner that
restricts relative movement between the bodies. It is preferred for
at least one of the protrusions and corresponding cavities (e.g.,
grooves) to be annular and contain an o-ring, for sealing
purposes.
[0009] According to one aspect of the present invention, the
polymeric body does not extend for the entire length of the
metallic body. In accordance with one embodiment of the present
invention, a forward end of the polymeric body, that defines the
forward opening, is readily viewable, whereas the other, rearward
end of the polymeric body is positioned between the ends of the
metallic body and is, therefore, substantially hidden from
view.
[0010] In accordance with one aspect of the present invention, the
polymeric body is formed by injecting molding material through a
hole in the sidewall of the metallic body. In accordance with some
embodiments of the present invention, the sidewall is cylindrical,
and the hole extends radially away from the axis which the
cylindrical side wall extends around. The hole in the sidewall of
the metallic body is preferably for receiving the molding material
from a gate in a jig that holds the metallic body in a
predetermined manner. It is preferred for the hole to be positioned
between the forward, viewable end of the polymeric body and the
substantially hidden, rearward end of the polymeric body.
Preferably the hole is closer to the rearward end of the polymeric
body than it is to the forward end of the polymeric body. This
advantageously helps to ensure that the polymeric body is fully and
properly formed within the metallic body. It is preferred for the
polymeric body to include a protruding portion that at least
partially occupies the hole, which further secures the bodies to
one another. Each of the composite fittings can include at least
one additional hole, which is for having molding material injected
thereinto, and associated structures.
[0011] In accordance with one aspect of the present invention, the
readily viewable forward end face of the polymeric body includes
indicia.
[0012] Further to one aspect of the present invention, the metallic
body of the composite fitting includes at least one spiral thread,
which can be internal or external, for facilitating connection of
the composite fitting to a piece of plumbing by twisting. The piece
of plumbing preferably includes metallic thread(s) for mating with
the thread(s) of the metallic body. The metallic body can include
an outer polygonal portion for being engaged by a wrench, for
facilitating the twisting.
[0013] In accordance with one aspect of the present invention, an
internal stop, which is preferably annular and part of the
polymeric body, protrudes into the passageway for engaging an end
of the polymeric pipe, or other piece of plumbing, inserted into
composite fitting, for arresting relative movement between the
composite fitting and the piece of plumbing (e.g., polymeric pipe).
Likewise, it is preferred for an internal or external stop, which
is preferably annular and part of the metallic body, to be
available for engaging an end of the metallic pipe or fitting, or
other piece of plumbing, installed to the composite fitting, for
arresting relative movement between the composite fitting and the
piece of plumbing (e.g., metallic pipe or fitting).
[0014] In accordance with one aspect of the present invention, the
composite fitting is advantageously compact as compared to
comparable conventional fittings.
[0015] Other aspects and advantages of the present invention will
become apparent from the following.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Having thus described the invention in general terms,
reference will now be made to the accompanying drawings, which are
not necessarily drawn to scale, and wherein:
[0017] FIG. 1 is a pictorial view of a composite fitting that is
for connecting between polymeric and metallic pipes, in accordance
with an exemplary embodiment of the present invention;
[0018] FIG. 2 is an elevational view of the front end of composite
fitting of FIG. 1;
[0019] FIG. 3 is a cross-sectional view of the composite fitting
taken along line 3-3 of FIG. 2;
[0020] FIG. 4 is an isolated pictorial view of a metallic body of
the composite fitting of FIG. 1;
[0021] FIG. 5 is an isolated cross-sectional view of the metallic
body taken along line 3-3 of FIG. 2;
[0022] FIG. 6 is an isolated pictorial view of a polymeric body of
the composite fitting of FIG. 1;
[0023] FIG. 7 is an isolated pictorial view of an o-ring of the
composite fitting of FIG. 1;
[0024] FIG. 8 schematically illustrates the composite fitting of
FIG. 1 connecting polymeric and metallic pipes, in accordance with
the exemplary embodiment of the present invention;
[0025] FIG. 9 schematically illustrates a molding machine for
manufacturing the composite fitting of FIG. 1, with the machine
containing the metallic body, in accordance with the exemplary
embodiment of the present invention;
[0026] FIG. 10 is an isolated, cross-sectional view of a portion of
the jig of the molding machine of FIG. 9, with the cross-section
taken along line 10-10 of FIG. 9;
[0027] FIG. 11 is an isolated, cross-sectional view of a portion of
the jig taken along line 11-11 of FIG. 9;
[0028] FIG. 12, is a cross-sectional view of a portion of the
molding machine of FIG. 9, with the machine containing the metallic
body and the cross-section taken along lines 12-12 of FIG. 10;
[0029] FIG. 13 is a cross-sectional view of a composite fitting in
accordance with another exemplary embodiment of the present
invention;
[0030] FIG. 14 is a cross-sectional view of a portion of a
composite fitting in accordance with other exemplary embodiments of
the present invention;
[0031] FIG. 15 is a pictorial view of a composite fitting in
accordance with another embodiment of the present invention;
[0032] FIG. 16 is a cross-sectional view of the composite fitting
of FIG. 15 taken along line 16-16 of FIG. 15; and
[0033] FIG. 17 is a cross-sectional view of the composite fitting
of FIG. 15 taken along line 17-17 of FIG. 15.
DETAILED DESCRIPTION OF THE INVENTION
[0034] The present inventions now will be described more fully
hereinafter with reference to the accompanying drawings, in which
some, but not all embodiments of the inventions are shown. Indeed,
these inventions may be embodied in many different forms and should
not be construed as limited to the embodiments set forth herein;
rather, these embodiments are provided so that this disclosure will
satisfy applicable legal requirements. Like numbers refer to like
elements throughout.
[0035] FIG. 1-3 illustrate a composite fitting 20 that is suitable
for connecting between pieces of plumbing such as, but not limited
to, polymeric and metallic pipes, in accordance with an exemplary
embodiment of the present invention. Although the composite fitting
20 is often described herein in the context of connecting between
polymeric and metallic pipes, the composite fitting 20 has other
uses that are not limited to connecting between polymeric and
metallic pipes. As one example, rather than being connected to a
metallic pipe, the fitting 20 can be connected to other devices
that can have metallic threads, such as valves, fittings or other
pieces of plumbing, or the like, that can be associated with
plumbing fixtures or appliances. Those of ordinary skill in the art
will understand that there are a wide variety of uses for the
composite fitting 20; and the present invention is not intended to
be limited to the embodiments described herein.
[0036] The composite fitting 20 includes a polymeric body 22 that
is preferably molded into and fixedly connected to a metallic body
24, and the bodies are preferably coaxial. The polymeric body 22
can consist essentially of polymeric material, and the metallic
body 24 can consist essentially of metallic material. The polymeric
body 22 is preferably fixed to the metallic body 24 by conforming
to the internal surface of the metallic body, as will be discussed
in greater detail below. It is preferred for the metallic body 24
to extend around the polymeric body 22, so that the metallic body
advantageously reinforces the polymeric body.
[0037] The polymeric body 22 extends around and is preferably
contiguous with (e.g., contacts/defines) a portion of a passageway
26 that extends through the composite fitting 20, and the polymeric
body defines a forward opening 28 to the passageway 26. The forward
opening 28 is preferably part of a receptacle of the composite
fitting 20 that is for internally receiving the polymeric pipe, as
will be discussed in greater detail below. Similarly, and as best
understood with reference to FIG. 3, the metallic body 24 extends
around and is preferably contiguous with (e.g., contacts/defines) a
portion of the passageway 26 of the composite fitting 20, and the
metallic body 24 defines a rearward opening 30 to the passageway
26. As illustrated in FIGS. 1-3, the rearward opening 30 is part of
an open plug portion 32 of the metallic body 24 that is for
externally receiving the metallic pipe. The plug 32 preferably
includes an external spiral thread 34 for connecting the plug to
the metallic pipe, or the like, by twisting, as will be discussed
in greater detail below. On the other hand, the thread 34 can be
omitted and the connection can be facilitated by other means. As
illustrated in FIGS. 1-3, the forward opening 28 and the rearward
opening 30 are the only openings to the passageway 26.
[0038] As best understood with reference to FIGS. 1, 2 and 4, the
metallic body 24 preferably includes an outer polygonal portion 36,
which is preferably hexagonal, for being engaged by a wrench, to
facilitate twisting of the composite fitting 20 for installation
purposes, as will be discussed in greater detail below. As best
understood with reference to FIG. 5, which is an isolated
cross-sectional view of the metallic body 24, it includes annular,
outwardly extending, forward and rearward cavities or grooves 38,
40 that respectively include annular, outwardly extending shoulders
which encircle, and preferably extend perpendicularly with respect
to, the central axis of the metallic body. As best understood with
reference to FIG. 4, it is preferred for a cylindrical hole 42 to
extend through a cylindrical sidewall 44 of the metallic body 24.
The hole 42 preferably extends radially away from the central axis
of the metallic body 24. That is, the hole 42 preferably extends
angularly away from the passageway 26 through the composite
fitting, and most preferably an angle of about 90 degrees is
defined between central axes of the hole and the passageway.
[0039] As best understood with reference to FIG. 6, which is an
isolated view of the polymeric body 22, it preferably includes a
generally cylindrical, annular midportion 46. Annular, outwardly
extending, forward and rearward protrusions 48, 50 are at opposite
ends of the midportion 46/polymeric body 22. The protrusions 48, 50
respectively include annular, outwardly extending shoulders that
encircle, and preferably extend perpendicularly with respect to,
the central axis of the polymeric body 22. The polymeric body 22
further includes a protrusion or stub 52 that extends outwardly
from the outer surface of the midportion 46. The stub is preferably
cylindrical and extends radially away from the polymeric body
22.
[0040] The forward protrusion 48 of the polymeric body 22 includes
a forward end face 54 that faces away from the metallic body 24,
and extends around and defines the forward opening 28. As
illustrated in FIGS. 1 and 3, the end face 54 is at least about
flush with the adjacent end of the metallic body 24, and preferably
the end face and the adjacent end of the metallic body are
substantially flush. In accordance with the exemplary embodiment of
the present invention, the surface area of the forward end face 54
is sufficiently broad so that it can be molded to include, or
otherwise marked to include, indicia (e.g., letters, numbers,
symbols and/or other markings for conveying information). As
illustrated in FIG. 2, exemplary indicia 56 of the forward end face
54 can be seen in an end elevational view of the composite fitting
20.
[0041] Referring to FIG. 6, the rearward protrusion 50 of the
polymeric body 22 includes a rearward end face 58 that faces one of
the shoulders of the metallic body 24 and is hidden from view in
the assembled configuration of the composite fitting 20. In
accordance with the exemplary embodiment of the present invention,
the rearward protrusion 50 includes an outwardly open, annular
groove 60 that, together with the rearward groove 40 (FIG. 5) of
the metallic body 24, contains/encases a polymeric o-ring 61 (FIG.
7) in the assembled configuration of the composite fitting 20. In
accordance with an alternative embodiment of the present invention,
the o-ring 61 is omitted.
[0042] The assembled configuration of the composite fitting 20 can
be best understood with reference to FIGS. 1 and 3, and with
occasional reference also to FIGS. 5 and 6. Relative movement
between the bodies 22, 24 is advantageously restricted by virtue of
the contact between the bodies, with that contact resulting from
the polymeric body having been molded into the metallic body. For
example, the protrusions 48, 50 (FIG. 6) of the polymeric body 22
respectively extend into the grooves 38, 40 (FIG. 5) of the
metallic body 24, so that the shoulders of the protrusions and
grooves respectively engage one another in a manner that restricts
relative movement between the bodies at least in the axial
direction. Likewise, the stub 52 (FIGS. 1, 3 and 6) of the
polymeric body 22 closes and occupies (e.g., plugs) the hole 42
(FIGS. 1 and 4) of the metallic body 24 in a manner that restricts
relative movement between the bodies in the axial direction. The
stub 52 can substantially fill the hole 42. In addition, the stub
52 occupies the hole 42 in a manner that restricts relative
rotation between the bodies 22, 24 about the central axis of the
composite fitting 20. That is, in accordance with the exemplary
embodiment of the present invention, the polymeric and metallic
bodies 22, 24 are connected to one another without requiring that
the metallic body be bent for facilitating this connection;
therefore, the composite fitting 20 is advantageously not weakened
by the connecting. In accordance with alternative embodiments of
the present invention, one or more of the stub 52, hole 42, grooves
38 and 40, and protrusions 48 and 50 are omitted, and it is within
the scope of the present invention for other contact between the
polymeric and metallic bodies 22, 24 to restrict undesired relative
movement therebetween.
[0043] As shown in FIGS. 2 and 3, in accordance with the exemplary
embodiment of the present invention, the polymeric body 22 further
includes an annular, inwardly extending protrusion 62 having
annular shoulders which encircle, and preferably extend
perpendicularly with respect to, the central axis of the composite
fitting 20. One of the shoulders of the protrusion 62 functions as
a stop for engaging an end of a polymeric pipe inserted into the
forward opening 28. The stop feature of the protrusion 62 is for
arresting relative movement between the polymeric pipe and the
composite fitting 20. The other shoulder of the protrusion 62 is
for engaging a corresponding shoulder of the metallic body 24 for
reinforcing the protrusion 62 and for further securing the bodies
22, 24 to one another. In accordance with an alternative embodiment
of the present invention, the inwardly extending protrusion 62 can
be omitted and/or replaced with another component that functions as
a backstop for the polymeric pipe.
[0044] As best understood with reference to FIG. 3, in accordance
with the exemplary embodiment of the present invention, the length
L1 of the polymeric body 22 is less than the length L2 of the
metallic body 24. Preferably the length L1 is about 33% to about
67% of the length L2, and most preferably the length L1 is about
43% of the length L2. Also in accordance with the exemplary
embodiment of the present invention, the plug portion 32 of the
metallic body 24 has a smaller outer diameter than the remainder of
the metallic body. As a result, an outer and outwardly extending
annular shoulder 63 of the metallic body 24 can function as a stop
for engaging an end of a metallic pipe or fitting installed onto
the plug portion 32, for arresting relative movement between the
composite fitting 20 and the metallic pipe or fitting.
[0045] FIG. 8 schematically illustrates a coupling, which includes
the composite fitting 20 and a metallic fitting 64, connecting a
polymeric pipe 66 and a metallic pipe 68 so that they are in fluid
communication with one another, in accordance with the exemplary
embodiment of the present invention. In accordance with one example
of the exemplary embodiment of the present invention, the metallic
pipe 68 is connected to the metallic fitting 64 in a conventional
manner, such as by soldering, or the like. In FIG. 8, the metallic
pipe 68 is partially illustrated by broken lines as extending into
an opening of a passageway that extends through the metallic
fitting 64. The metallic pipe 68 and the metallic fitting 64 can be
together referred to as a metallic pipe. For the embodiment
illustrated in FIG. 8, an opening of the passageway that extends
through the metallic fitting 64 includes internal threads 70 that
are hidden from view and are, therefore, schematically illustrated
by broken lines in FIG. 8. The external threads 34 (FIGS. 1 and
3-5) of the composite fitting 20 are threaded into the internal
threads 70 of the metallic fitting 64 by relatively twisting the
fittings. Accordingly, broken lines in FIG. 8 illustrate the
composite fitting 20 extending into the passageway that extends
through the metallic fitting 64.
[0046] As alluded to previously, the composite fitting 20 can be
connected to items other than the metallic fitting 64 and metallic
pipe 68. For example, other plumbing items can be connected to the
composite fitting 20 in place of the metallic fitting 64 and
metallic pipe 68. As one example, the threads 34 of the composite
fitting 20 can be mated with metallic threads of valves, fittings
or other pieces of plumbing, or the like, that can be associated
with plumbing fixtures or appliances. Those of ordinary skill in
the art will understand that there can be a wide variety of uses
for the composite fitting 20.
[0047] An end of the polymeric pipe 66 is inserted into the forward
opening 28 (FIGS. 1-3) of the composite fitting 22 and secured
therein by way of solvent welding, adhesives, or the like. Broken
lines in FIG. 8 illustrate the polymeric pipe 66 extending into the
forward opening 28 of the composite fitting 20. Although not
illustrated in the figures, and as best understood with reference
to FIGS. 1 and 6, it is preferred for the entirety of the annular
edge of the polymeric body 22 that defines the forward opening 28
(e.g., the edge of the of the polymeric body 22 which is located at
the inner periphery of the forward end face 54) to be slightly
rounded or chamfered in a manner which facilitates insertion of the
pipe 66 into the forward opening 28.
[0048] In accordance with the exemplary embodiment of the present
invention, the metallic body 24 is brass, or the like, and the
metallic pipe 68 is copper, or the like. In accordance with
alternative embodiments of the present invention, the metallic body
24 and metallic pipe 68 are constructed of other metals, and they
can include, or be constructed of, materials other than metals. In
accordance with the exemplary embodiment of the present invention,
the polymeric body 22 and the polymeric pipe 66 are chlorinated
polyvinyl chloride (CPVC), or the like. In accordance with
alternative embodiments of the present invention, the polymeric
body 22 and pipe 66 are constructed of polymers other than CPVC,
and they can include, or be constructed of, materials other than
polymers.
[0049] FIG. 9 schematically illustrates a portion of a molding
machine 72 for forming the composite fittings 20, in accordance
with the exemplary embodiment of the present invention. It is
preferred for the molding machine 72 to manufacture multiple of the
composite fittings 20 simultaneously; however, and for purposes of
clarifying this disclosure, only a representative portion of the
molding machine 72 is illustrated in FIG. 9. As schematically
illustrated in FIG. 9, the machine 72 includes an actuator 74 for
moving a mold insert 76 relative to a jig 78. The actuator 74 moves
the mold insert 76 between a molding configuration and a loading
configuration. As will be discussed in greater detail below, the
composite fitting 20 is formed during the molding configuration. In
contrast, the loading configuration is for loading and unloading,
as will be discussed in greater detail below. FIG. 9 schematically
illustrates the molding configuration, in which the metallic body
24 is hidden from view within the closed jig 78, and a portion of
the mold insert 76 is hidden from view within the jig and the
metallic body; and these hidden from view items are schematically
illustrated by broken lines in FIG. 9.
[0050] FIGS. 10 and 11 are partial, isolated, cross-sectional views
of the jig 78, in its closed configuration, respectively taken
along lines 10-10 and 11-11 of FIG. 9. FIGS. 10 and 11 illustrate
that the openable and closable jig 78 includes opposite halves. The
opposite halves of the jig 78 are closed/locked together during the
molding configuration of the molding machine 72, and they are
unlocked/separated from one another during the loading
configuration of the molding machine. When closed/locked together,
the opposite halves of the jig 78 together define a receptacle 80
for initially holding a metallic body 24 and subsequently holding a
composite fitting 20 formed by molding a polymeric body 22 into the
metallic body being held. In accordance with the exemplary
embodiment of the present invention, the receptacle 80 of the jig
includes adjacent polygonal and cylindrical envelopes that are
respectively illustrated in FIGS. 10 and 11. The polygonal envelope
of FIG. 11 is most preferably hexagonal and is for closely engaging
and extending around the hexagonal portion 36 (FIGS. 1 and 2) of
the metallic body 24. The cylindrical envelope of FIG. 10 is for
closely engaging and extending around the outer surface of the
cylindrical sidewall 44 (FIGS. 1-3) of the metallic body 24.
[0051] Referring to FIG. 10, the receptacle 80 is for holding the
metallic body 24 in a predetermined position so that the hole 42
(FIGS. 1 and 4) in the sidewall 44 of the metallic body is aligned
with a gate 82 (e.g. passageway for supplying molding material) of
the jig 78 during the molding configuration. Referring to FIG. 9,
the gate 82 is in fluid communication with conventional equipment
84 for providing molding material under pressure, and the gate is
for injecting the molding material into the hole 42. The gate 82
and portions of a supply channel 86 connecting the gate to the
equipment 89 that is the source of molding material are hidden from
view in FIG. 9; therefore, broken lines illustrate them.
[0052] The molding configuration is partially illustrated in FIG.
12, which is a cross-sectional view taken along line 12-12 of FIG.
10 and is illustrative of the jig 78 in its open configuration, in
accordance with the exemplary embodiment of the present invention.
In the molding configuration, the metallic body 24 is held in the
predetermined configuration in the jig 78 and the mold insert 76 is
in the passageway through the metallic body 24 so that an annular
chamber 88 is defined between the metallic body and the mold
insert. The metallic body 24 extends around the chamber 88 and the
chamber 88 extends around the mold insert 76. At the same time, the
mold insert 76 annularly engages surfaces of the metallic body 24
so that the chamber 88 is substantially closed, except for being in
communication with the gate 82. In accordance with the exemplary
embodiment of the present invention, the mold insert 76 generally
resembles a cylindrical rod that is tapered in somewhat of a
stepped fashion so as to include a predetermined arrangement of
annular bevels and shoulders. The cross-section of the mold insert
76 that is illustrated in FIG. 12 is preferably representative of
all straight cross-sections that can be taken through and
perpendicular to the central axis of the mold insert. Although it
is preferred for the metallic body 24 to contain the o-ring 61
(FIGS. 3 and 7) during the molding of the polymeric body 22, the
o-ring is omitted from FIG. 12 to clarify the view.
[0053] During the molding configuration illustrated in FIG. 12, the
molding material (e.g., liquid CPVC) is injected into the chamber
88 via the gate 82 and the hole 42, so that the hole 42 functions
as an injection point by way of which the molding material is
introduced into the chamber 88. This injecting is carried out so
that the chamber 88 and hole 42 are preferably completely filled,
and then the molding material in the chamber 88 is allowed to
solidify, so that it becomes the rigid polymeric body 22. That is,
the polymeric body 22 is preferably formed in the metallic body 24
by injection molding. As will be discussed in greater detail below,
it is preferred for the molding material to be injected with
sufficient pressure and/or under other conditions so that the
o-ring 61 is compressed in a radially outward direction during the
injection molding, so that the o-ring can, if required,
subsequently expand and contract to compensate for any differences
in the expansion and contraction of the polymeric and metallic
bodies 22, 24 and thereby enhance leak-proof functioning of the
composite fitting 20. The molding machine 84 is transitioned to the
loading configuration after the injection molding.
[0054] In the loading configuration of the molding machine 24, the
mold insert 76 has been withdrawn preferably at least from the
receptacle 80 (FIGS. 10 and 11) of the jig 78. Then, the jig 78 can
be opened and the composite fitting 20 can be removed from the jig.
In accordance with the exemplary embodiment of the present
invention, breaking the composite fitting 20 away from the
polymeric material that solidified in the gate 82 and channel 86
completes fabrication of the composite fitting. That is, an annular
shoulder/face 91 (FIG. 12) of the mold insert 76 preferably
includes indicia (not shown) so that the indicia 56 (FIG. 2) of the
composite fitting 20 is formed during molding of the polymeric body
22. Solidified polymeric material in the gate 82 and supply channel
86 is preferably cleared prior to forming the next composite
fitting 20. Then, a metallic body 24 can be placed in the
receptacle 80 of the jig 78 and the molding machine 84 can be
returned to the molding configuration.
[0055] As best understood with reference to FIG. 3, the hole 42 in
the sidewall 44 of the metallic body 24 is preferably positioned
farther from the forward end face 54 of the polymeric body 22 than
from the hidden, rearward end face 58 of the polymeric body. This
advantageously helps to ensure that the polymeric body 22 is fully
and properly formed within the metallic body 24. That is, from a
quality control standpoint, a visual confirmation that the readily
viewable forward end face 54 of the polymeric body 22 is fully
formed should advantageously also serve as a confirmation that the
hidden, rearward end face 58 and other portions of the polymeric
body are fully formed, since the hole 42 is closer to the rearward
end face than it is to the forward end face. In accordance with
alternative embodiments of the present invention, the hole 42 is
arranged differently, and it is possible that the hole 42 could be
omitted, such as by including the gate 82 (FIGS. 9 and 12) in the
mold insert 76 rather than the jig 78.
[0056] FIG. 13 is a cross-sectional view of a composite fitting 20'
that is like the composite fitting 20 described with reference to
FIGS. 1-12, except that the composite fitting 20' of FIG. 13
includes an internally threaded receptacle 90 for internally
connecting the composite fitting 20' to a metallic pipe or fitting.
The threading of the internally threaded receptacle 90 terminates
proximate an inner and inwardly extending annular shoulder 92. The
shoulder 92 can function as a stop for engaging an end of a
metallic pipe or fitting installed into the receptacle 90, for
arresting relative movement between the composite fitting 20' and
the metallic pipe or fitting.
[0057] FIG. 14 is a cross-sectional view of a portion of a
composite fitting 20'' that is, in accordance with a first
embodiment of the present invention, like the composite fitting 20
described with reference to FIGS. 1-12, and that is, in accordance
with a second embodiment of the present invention, like the
composite fitting 20' of FIG. 13, except that for each of these
first and second embodiments, the metallic body 24'' further
includes an axial groove 94 which is occupied by an axial
protrusion 96 of the polymeric body 22''. Each of the axial groove
94 and the axial protrusion 96 encircles and extends preferably
parallel to the central axis of the metallic body 24''. As
illustrated in FIG. 14, the axial groove 94 includes a pair of
shoulders that are radially spaced apart from one another, and that
are each coaxial with the central axis of the composite fitting
20''. Accordingly, in accordance with the first and second
embodiments of the present invention, the metallic body 24''
includes annular grooves that extend nonparallel to one another,
the polymeric body 22'' includes annular protrusions that extend
nonparallel to one another, and the protrusions are respectively
positioned in the grooves in a manner which seeks to stabilize the
composite fittings/allow the composite fittings to function
optimally.
[0058] FIGS. 15-17 illustrate a composite fitting 20''' in
accordance with another embodiment of the present invention. The
composite fitting 20''' is like the composite fitting of the second
embodiment of the present invention except that the metallic body
24''' of the composite fitting 20''' is modified. The metallic body
24''' is angled, such as to define a 90.degree. angle, so that the
composite fitting 20''' is in the form of an elbow. That is, the
portions of the passageway 26''', which respectively include the
openings 28 and 30''', respectively extend around axes, and an
angle is defined between these axes, such as angle of 90.degree.
Other angles are also within the scope of the present invention.
Also, the metallic body 24''' includes ears or lobes 100 that are
generally of the type that are included in conventional drop ear
elbows. A hole 102 extends completely through each of the lobes
100. Fasteners, such as nails or screws, can be inserted through
the holes 102 for the purpose of mounting the composite fitting
20''' to a reference structure, such as a stud or other structural
component of a building, or the like. Also, the metallic body 24'''
optionally includes an annular flange 98 that encircles the opening
30'''. As illustrated in FIGS. 15-17, the metallic body 24''' does
not include the outer polygonal portion 36 (e.g., see FIG. 1), but
the metallic body 24''' can optionally include the outer polygonal
portion 36.
[0059] In accordance with exemplary embodiments of the present
invention, feature(s) of the composite fittings advantageously
operate in a manner which seeks stabilize the composite
fittings/allow the composite fittings to function in a leak-proof
manner for very many years, even if exposed to many extreme cycles
of stress, such as may be caused by variations in the pressure
and/or temperature of the water or other medium passing through the
composite fittings. In this regard, and for example, it is
preferred to incorporate the o-ring 61 as described above, because
it can perform a sealing function that negates effects of different
coefficients of expansion between the metallic and polymeric
bodies. In this regard, it is believed that the functionality of
the O-rings 61 can be enhanced by compressing (e.g., "flattening")
the O-rings in a radially outward direction when molding the
polymeric bodies into the metallic bodies, so that the O-rings can,
if required, subsequently expand and contract to compensate for any
differences in the expansion and contraction of the metallic and
polymeric bodies.
[0060] Such compressing of the O-rings 61 during manufacture can be
enhanced, for example, by decreasing their modulus of elasticity,
such as by preheating the o-rings. As an additional example, the
molding material (e.g., see the source of molding material 84 in
FIG. 9) can be injected in a manner that enhances the compressing
of the O-rings 61, such as by injecting the molding material at
higher pressures, increasing the duration of the injecting, or
making the pressure gradient of the injected molding material more
uniform. As one example, and as best understood with reference to
FIGS. 9 and 10, which only show one gate 82 per receptacle 80, it
may be possible to achieve a more uniform pressure gradient by
injecting the molding material into each receptacle through more
than one gate, such as via two gates which are diametrically
opposed, or the like.
[0061] Many modifications and other embodiments of the inventions
set forth herein will come to mind to one skilled in the art to
which these inventions pertain having the benefit of the teachings
presented in the foregoing descriptions and the associated
drawings. Therefore, it is to be understood that the inventions are
not to be limited to the specific embodiments disclosed and that
modifications and other embodiments are intended to be included
within the scope of the appended claims. Although specific terms
are employed herein, they are used in a generic and descriptive
sense only and not for purposes of limitation.
* * * * *