Note: Descriptions are shown in the official language in which they were submitted.
1 FIELD OF_THE INVENTION
This invention relates to fittings for an eavestroughing
system and more particularly to a fitting which has a sealing
member molded on its interior surface for purposes of securing
the sealing member to the fitting.
BACKGROVND_OF THE INVENTION
Common practice for eavestrough installations is to form
- the eaves~rough and the fittings therefor of metal, where the
fittings are used to assemble the troughing for attachment to
the eave of a building. In using metal trough, it was always
necessary to join them together by soldering techniques.
There is now a definite move in the industry towards the use
of plastic eavestroughing with plastic fittings and/or the
combination of metal troughing with plastic fittings. To
Eacilitate installa~ion of eavestroughing systems using
plastic fittings and trough, there was a move away from glue
and soldering techniques to join trough sections, because
these techqnles were usually outside of the skill of the
average homeowner. Advances have been made in fittings which
provide for the joining of trough portions together and other
connections. It is noted that reference to eavestroughing is
also meant to refer to guttering systems.
An example of an eavestroughing or guttering system
having fittings provided with seals is disclosed in British
Patent 1,065,596. Plastic eavestroughing sections are clamped
together in a fitting having resilient foamed rubber pads.
The troughing is placed in the fitting and clamps are located
over the fitting and troughing to clamp the trough sections to
the fitting. Recesses are provided in the fi~ting to receive
the foamed rubber pads. A similar arrangement is disclosed in
4~
1 British Patent 1,090,291. Resilient sealing strips are used
in the fitting and usually consi~ts of a synthetic rubber,
5uch as neoprene. The sealing strips are secured to the
interior of the fitting by a suitable adhesive and is intendQd
to form a seal with the eDd of the plastic eavestroughing or
guttering.
British Patent 993,55~ discloses the snap fitting of
troughing sections into fittings which again have sealing
members adhered to the fitting. The sealing members may be
sponge rubber or other suitable deormable material. Canadian
Patent 691,~03 alsc discloses a similar system where the
eaves~roughing sections are snap fitted into ~he fitting. The
fitting includes a foam rubber sealing pad which is located
between the eavestroughing section and the fitting.
United States Patent 4,257,716 discloses an
eavestroughing system of common assignee where metal
eavestroughing is used in combination with plastic fittings.
The plastic fittings include sealing members of foamed
resilient material which are glued to the fitting by an
appropriate adhesive.
With the above fittings the sealing member is either
loosely located in the fitting or adhered to the fitting by an
adhesive. Such cutting of sealing members and locating them
in the fittings are labour intensive and are subject to error,
not only due to improperly glueing them in the fitting, but
also variations in the thicknesses of the sealing member can
result in leakage problems.
Eavestroughing, according to this invention having the
sealing member molded on a preformed fitting, overcomes the
above problems with existing eavestrough fittings and provides
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1 several advantages not reali~able by the prior fitting
arrangements.
SUMMARY OF_THE INVENTION
The eavestrougb fitting, according to this invention, is
for attachment to an end portion of a length o
eavestroughing. The fitting has a compressible seal of a
material dissimilar in physical properties to the material of
the fitting. The seal is secured to the fitting by molding
the seal in a mold cavity onto the preformed fitting. The
seal is configured to approximate the configuration of the
eavestrough~ Means is provided for compressing the seal
be~ween an end portion of the eavestrough and the fitting to
seal such eavestrough to the fitting.
The method, according to this invention for molding the
sea] onto the fitting, comprises supporting the preformed
fitting and inqerting a mold core against the ~upported
fitting interior surface to define by a recessed portion in
the mold core a cavity in the shape of the desired seal
member. Molten plastic material of suitable resilient
properties when set, is injected into the cavity ~o form the
sealing member. The injected plastic material is allowed to
set and then tAe mold core is removed from the fitting leaving
the sealing member secured to the fitting interior surface.
The fitting has a socket to receive the eavestrough end
portion, where the fitting has spaced-apart tab portions at
the upper regions of the fitting socket. A resilient insert
may be used for qnap fitting under the tab ~ortions to
compress the seaLing member between the eavestrough and the
fitting to form thereby a seal between the fitting and the
e~vestrough. The eavestrough may be shaped to also snap fit
1 within the fitting socket by engaging the tab portions. In
using the resilient insert, additional pressure is applied for
compressing the seal between the eavestrough and the fitting
to ensure a seal. The resilient insert may be Eormed of a
material which is not affected by tamperatures exceeding 140
degrees F which can occur when the eavestroughing system is
exposed to direct sunlight.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention are shown in the
drawings wherein:
Figure 1 is a perspective exploded view showing various
components of an eavestroughing system, according to the
invention;
Figure 2 is an exploded view showing an endcap to be
connected to an end portion of a length of eavestroughing;
Figure 3 is a perspective view of an endcap fitting;
Figure 4 is a side elevation of the endcap of Figure 3
showing an end portion of an eavestrough to be inserted
therein;
Figure 5 shows the eavestrough snap fitted in the endcap
portion of Figure 3;
Figure 6 is a cross-section of the endcap of Figure 5
along the lines 6-6 of Figure 5;
Figure 7 is a perspective view showing the use of a
resilient inserl: to sacure the eavestrough end portion in the
endcap;
Figura 8 is an exploded view of mold components used in
injection molding the sealing member onto the interior suxface
of the preformed endcap fitting;
Figure 9 shows the insertion of the collapsible mold
22
1 core into the preformed endcap fitting which is supported by
the mold block; and
Figure 10 shows the collapsible core of Figure g
e~panded against the in~erior sur~ace of the preformed fitting
in preparation for injection molding of the sealing member
onto the interior surface of the endcap Eitting.
DETAILED DESCFIPTION OF THE PREFE ~R~D ~M~OD/U~N--
To facilitate installation of precut lengths of
eavestroughing or guttering, fittings are used in joining the
lengths of trough together, to provide for downspout portions,
mitre fittings traversing corners of buildings and providing
blank ends for the troughing system. The fittings have been
designed with a view to assisting the homeowner and other
do--it yourselfers to facilitate installation of the
eavestroughing. To avoid having to make seals between the
lengths of trough, should they be metal or plastic, the
fittings are adapted to sealingly engage the trough end
portion and to provide for downspo~ts, endcaps, miter joints,
etc~
Referring to Figure 1, several of the fittings and
downspout arrangements are shown. Lengths of eavestroughing
10 having end portions 12 are inserted in the various types of
fittings shown in Figures 1 and 2. The fittings include
joiner 14, a centre drop downspout fitting 16, a miter fitting
18 for traver~ing corners of buildings and an endcap fitting
20. Although not shown, another fitting commonly used is the
end drop downspout. Each fitting is adapted to sealingly
engage the end portion 12 of each length of eavestroughing
10. With the centre drop downspout fitting 16, it has
provided centrally thereof a hole 22 and depending from the
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1 underside of the fitting 16 is a spigot 24, which is sized to
be inserted within the downspout piping 26.
Each of the fittings is provided with a sealing member.
The joiner has two sealing members 28 and 30 which engage the
respective end portions 12 of eavestroughing section 10.
Similarly, fitting 16 is provided with two sealing members 32
and 34 which also engage the respective end portions of the
troughing. Miter 18 has sealing members 36 and 38 which
engage the respective end portions 12 of the eavestroughing
which e~tend along each side of the building away from the
corner. Similarly, fitting 20 has sealing member 40 for
engaging a free end 12 of an eavestroughing section 10. By
providing each fitting with a sealing member to sealingly
engage each trcugh section, water can then flow along the
eavestroughing over the joiners and other fittings and drain
collected water away through the centre drop downspout piping
26. The seals prevent any water carried by the troughing
leaking out between the troughing and the fittings.
Each of the fittings is provided with tab portions which
are identically formed on each fitting and are generally
referred to as tab portions 42 and 44 on endcap fitting 20 of
Figure 2. The tab portions are provided at the upper
e~tremities of the socket or recess of the f itting to receive
the troughing. The tab portions are used in securing the
troughing section in the f itting and in compressing the
compressible sealing member to sealingly engage the fitting
with the troughing.
Turning to Figure 3, further details of a representative
fitting are shown. It is appreciated that all fittings have
the same feat~lres with respect to the sealing member and ~ab
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1 portions, so that details in referring to the endcap of Figure
3 applies equally well to the oth~r fittings of 14, 16 and 18
which all must sealingly engage the eavestroughing.
The endcap fitting 20 of Figure 3 has a body portion 46
which defines a recess generally designated 48 and defined by
the interior surface 50 of the fitting body portion. In view
of the rectilinear shape of the eavestroughing, the socket or
recess 48 has a similar shape, so that the body portion of the
fitting 20 consists of a base 52 and generally integrally
formed upstanding sidewalls 54 and 56. At the upper
extremi~ies of each sidewall are integrally formed tab
portions 42 and 44. Since the endcap fitting closes off the
end of the eavestroughing, the body portion also includes an
end wall 58 to prevent water flowing out the free end of the
eave~troughing. The sealing member 40 is molded onto the
interior surface 50 of the eavestrough fitting 20. The
sealing member is compressible and consists of two upstanding
fin portions 60 and 62.
As shown in Figure 4, the tab portions 42 and 44,
according to this preferred embodiment, act as clips into
which the end portion 12 of tha eavestroughing is sn~p
fitted. The end portion 12 of the eavestroughing, as shown in
dot in Figure 4~ has one edge 64 inserted in clip portion 42.
The trough is forced down into the fitting 20, so as to be
snap fitted under the clips 42 and 44 and take on the shape as
shown in Figure S as it compresses the sealing member 40
between the eavestrough and the fitting. The eavestroughing,
as with the fitting, consists of a base portion 66 and
generally upstanding wall portions 68 and 70. Each wall
portion is ang~ed slightly at 72 to provide a vertical portion
1 74~ which presents the respective eavestrough edges 64 and
76. Clip portions 42 and 44 have depending ledges 88 and 90
to re~cain the trough edges when snap fitted into the clips.
The ledges resist dislodging the trough from the fit~ings when
a lateral force is exerted on the trough, such as, leaning a
ladder against the trough section.
The compressible sealing member 40 is dimensioned
relative to the clip portions 42 and 44 such that, when the
edges 64 and 76 of the eavestroughing are snap fitt~d therein,
the sealing member is compressed along the sidewall portions
68 and 70 and the base portion 66. In snap fitting the
eavestroughing into the fitting 20, the base portion 66 tends
to bow upwardly slightly about junctures 78 and 80. To
compensate fox this bowing, the sealing member 40 varies in
thickness along lts length in a predetermined manner to
resemble the shape of the eavestroughing end portion 12 when
snap fitted into the fitting. Thus, the sealing mamber 40 is
thinner in the juncture area 78 and 80 of the eavestroughing
than in its central region 82, to match the configuration of
the base portion 66 of the eavestrough as snap fitted into t~e
fitting. This ensures a leak tight sealing engagement with
the base portion of the fitting. Similarly with the sidewalls
of the troughing, they are sealingly contacted by the sealing
member 40, æo that no leakage can occur along the junctures 78
and 80 and along the sidewalls 68 and 70 of the
eavestroughing.
~ s shown in Figure 6, the fitting 20 has the trough end
portion 12 snap fitted therein to sealingly engage the sealing
member 40. The sealing member consists of two upright fins 60
and 62. Interconnecting the upright fins 60 and 62 is a
1 planar base 84. 8ase 84 adds support to the ~ins 60 and 62
and also is useful in en~uring a secure bonding of the seal
member 40 to tbe in~erior surface 50 of the fitting.
Accordingly~ the fittings of Figures 1 and 2 having the
clip portions 42 and 44 provide the means for compressing the
seal between the eavestroughing end portion and the fitting.
It is appreciated, of course, tha~ other devices may be
employed to effect such compression or supplement the
compression exerted by snap fitting the eavestroughing into
the fitting. Referring to Figure 7, the fitting 20 has the
eavestrough end portion 12 snap fitted into the clips 42 and
44. To apply additional compression on the seal sandwiched
between the eavestrough and fitting, a resilient insert 86 is
used which is snap fitted into the clips 42 and 44. There is
sufficient room within the ledges 88 and 90 of the clip
portions to accommodate the edges 92 and 94 of the insert 86.
ThP insert 86 has a shape corre ponding to the interior shape
of the eavestrough 12, only dimensionally somewhat smaller.
With the insert 86 snap fitted into the clips 42 and 44,
addi~ional presssure is exerted on the sealing member. The
base portion 96 of the insert may be bowed downwardly slightly
such that, when snap fitted into the fitting, the additional
pressure is maintained on the fitting and along ~he base 66 of
the eavestrouqhing section 12.
In instances where it is not desired to snap fit the
troughing into the fitting, the insert 86 may be used as the
sole means for compressing the seal between the eavestroughing
and the fitting. In that instance, the eavestroughing edges
do not clip within the clip portions 42 and 44. Instead the
insert 86 would be used to snap fit in the clip5 42 and 44 to
1 exert the compressive forces on the seal along the base
portion 66 and the sidewall portions 68 and 70 of the
eavestrough to sealingly engage the fitting with the
eavestrough end portion 12.
Aside from complementing the clips 42 and 44 in sealing
of the eavestroughing in the fitting, the resilient insert ~6
may be used in association with eavestroughing when its
temperature exceeds the softening temperatures of the
plastic. The eavestroughing may be formed of various colours,
such as whiter brown and other pastel colours. With darker
colours such as dark brown, the troughing absorbs more of the
radiation from direct sun and can increase the troughing
temperature to well above its softening point of 140 degrees
F. This will permit the eavestroughing base portion 66 to bow
upwardly and break its sealing engagement with the seal 40.
Because the troughing is formed o a rigid polyvinylchloride,
once softened it will not resume its original shape, so that
the exaggerated bow in the trough bottom will not reseal with
the sealing member 40. The insert 86, as it applies
additional compressive force on the troughing, prevents this
unwanted bowing from occurring. The compression insert 86 is
formed of a resilient material which will resist softening at
these higher temperatures. 5uitable insert materials are
those of the pol~carbonates which are thermoplastic and will
not loose their resiliency once subjected to the higher
temperatures of greater than 140 degrees F under direct
sunlight. The inserts are used with whatever fittings include
sealing portions, such as those illustrated in Figures 1 and
2~ namely the eavestrough joiner 14, the centre drop fitting
16, the miter 18 and the endcap 20. ID each instance, the
1 compression clip a6 is of the same configuration.
Although a rectilinear shape for ~he eavestroughing has
been described with respect to the preferred embodiment, it is
appreciated that other cross-sections for troughing may be
used with appropriate change in fitting shape. For example,
the troughing may be somewhat circular with correspondingly
shape Eitting and sealing member.
The use of the insert 86 then allows the installation of
a wider range of colours for the eavestroughing system and
also provides for alternates to snap fitting of the troughing
into the fittings.
As disclosed in United States patent 4,257,716, it was
the prior practice to glue the foam rubber sealing strip in
the eavestrough fitting. This had several drawbacks including
a labour intensive step, unrealiability in always providing a
good seal in the fitting and the inconsistencies of the
extruded foamed rubber resulting in poor sealing contact with
the troughing, particularly along the base portion where a
lack of foam rubber could be critical to assuring a leakproof
structure~ The sealing member, according to this invention,
is molded onto the preformed fitting to provide improved
control on the shape of the sealing member to ensure a
consistent shape for sealing member from fitting to fitting.
To accomplish this objective, the preformed fitting is located
in a mold to support the surfaces of the fitting onto which
the sealing member will be molded. Referring to Figure 8, a
schematic representation of a mold is shown.
It is appreciated that many techniques are available for
molding of a plastic material onto a preformed product.
Examples are provided in Canadian Patents 668,709 and
16~2~
1 758,052. In Canadian Patent 668,709, a ball and socket joint
assembly is formed by injection molding plastic materiai
around a preformed ball stud. In Canadian Patent 768,052, a
compatible thermoplastic material is injection molded between
preformed thermoplastic shapes to join the shapes together to
form an integral structure, which may be in the shape of a
container or the like. Other e~amples of injection molding or
molding a plastic material onto a preformed part are disclosed
in United States Patent 4,115,506 and Canadian Patents
1,032,320 and 1,070,071.
According to the embodiment shown in Figure 8, a mold
block 98 consists of a female mold recess 100 which has
supporting surfaces 102, 104 and 106 for supporting the base
portion 66 and wall portions 68 and 70 of the fitting 22 to be
inserted in the direction of arrow 108. Schematically
represented is a block 110 having the runner system for
delivering the molten plastic to be injected into the cavity
through bore 112. Pins 114 are located on the base 102 of the
mold block to support the base portion 66 in the mold and
prevent lateral movement in retaining it against wall 116 of
the female recess 100. The collapsible core 118 is mounted on
guides, not shown, which are adapted to engage bars 120 and
122 for guiding movement of the collapsible core 118 into the
interior of fitting 20. The collapsible core 118 consists of
two core parts 124 and 126. Each sidewall 128 and base
portion 130 of core 124 and 126 has a recess 132 formed
therein provided with grooves 134 and 136 to define the
cavities in forming the fins 60 and 62 and correspondingly the
planar recess area 138 defines the base 84 of the sealing
member.
8~:22
1Turning to Figure 9, the collapsible core 118 is lowared
in the direction of arrow 140 along guide rods 120 and 122.
The bore 112 of the runner system 110 is partly above the base
66 of the eavestrough fitting 20 as it rests in the mold
recess area 100. As shown in dot at 142, the outline for the
fin recesses is shown. The core in the collapsed mode is
inserted in the fitting and expanded by a wedge forced between
cam faces 144 and 146 of the core 118 to move the parts in the
direction of arrows 148 and 150. ~ith sufficient presquxe,
10the core faces 128 and 130 of each part 124 and 126 form a
cavity of the shape of the sealing member. Molten plastic is
injected in through bore 112 to fill the formed cavityO Once
the molten plastic material has set or solidified within the
cavity, the core is collapsed in the direction reverse to
arrows 148 and 150 and withdrawn. The fitting is retrieved
from the mold recess 100 with the sealing member now formed
thereon.
~ t is appreciated that with the various fitting shapes
and sizes, the mold recess 100 may have to be modified to
accommodate the particular fitting. With the joiner fitting
1~, two sealing members 28 and 30 are provided therein which
are formed in a single mold. The collapsible core has two
recesses formed therein and spaced apart to the extent shown
to form both the sealing members at the same time from a
common hot runner system.
The sealing material is selected such that when injected
in a molten state onto the fitting surface the molten injected
material causes a bonding of the set sealing material onto the
clean fitting surface. For example, when th~ fitting is
formed of a rigid polyvinylchloride, then a more flexible
13
, ~,6~æ
1 plastic~zed polyvinylchloride is used as a suitable sealing
material. Due to the similarity in the makeup of the two
constituents, a physical bond by Eusion is formed between the
injected sealing member and the fitting to ensure that the
sealing member is always secured to the fitting during
transportation, selling and installation of the eavestrough
itting.
In situations where the sealing material is not
compatible and will not ~use with the material of the fitting,
undercut portions may be provided in the preformed fitting
such that, when the sealing material is injected, it is
gripped by the undercut portions to retain the sealing member
on the fitting. When the sealing member is compressed between
the eavestrough and the fitting, a seal is provided at all
areas.
In forming the sealing member with fin portions 60 and
62, and as secured to the fitting interior surface, support is
provided for the fins which do not collapse yet allow movement
of the eaYestroughing relative to the fitting during thermal
contraction and expansion of the eavestroughing system in
extremes of hot and cold. With the sealing members secured to
the fitting, the sealing member is not moved out from the
fitting to ensure that a seal is retained throughout the
usable life of the eavestroughing system.
Because of the injection molding techniques, complete
control can be exercised on the shape of the sealing member to
ensure that a proper seal is formed for all desired shapes and
siæes of eavestroughing. As shown in Figure 4, the height of
the sealing member 40 varies along the length of the seal to
approximate the contour of the eavestroughing. The height of
14
S~ %2
1 the sealing member along the base area 82 is slightly curved
as explained to take on the shape of the troughing when snap
fitted into the fitting 20. Also as shown in Figure 3, a
sprue 41 from the hot runner bloclc 110 of the mold of Figure 8
remains on the surface 52 of the ~Eitting.
By injection molding the sealing member on the fitting,
several advantages are obtained from a marketing and
manufacturing standpoint. The seal will not fall out of the
fi~ting and provides a solid arrangement for the sealing
member. The area within the fitting i8 clean with no
unsightly glue and the like. By maintaining the shape of the
seal, the fitting is functionally a better product and more
readily installed. It maintains its shape and at the retail
level ls not readily removed ~rom the fitting, so that the
retailer need not be concerned with seals falling out oP the
fittings and having to repair them at the store. The sealing
member as mentioned may be formed from a plasticiæed
polyvinylchloride material. This material can be purchased
from B.F. Goodrich under the trademark GEON, Product No.
~0 M544. The lnjection molding of the gasket sealing material
can be exactly tailored to the product shape and thereby
optimized on its sealing properties. The method of
manufacturing also eliminates several present safety hazards
and health problems associated with using adhesives to glue
the foam rubber sealing member into the fitting.
Although various embodiments of the invention have been
described herein in detail, it will be understood by those
skilled in the art that variations may be made therato without
departing from the spirit of the invention or the scope oE the
appended claims.
