Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to means for interconnec-
ting leng-ths of pipe and more particularly to a joint for
vertically standing pipe used in buildings.
A building constructed mainly of wood has one
great disadvantage which has proven troublesome over the
years and that is the natural tendency of the structure to
become compacted to a slight extent due to its own weight
and the loads it is required to carry. A wood frame build-
ing, for example, is known to settle as much as one half an
inch for each storey of the structure and this presents
problems particularly in the plumbing. The soil and other
pipes which stand vertically and extend from the top floor
to the basement of the building are usually formed of cast
iron with the joint connecting the pipe sections between
each floor. Because of the settling of the building, the
pipe sections move relative to one another to such an extent
that the joints will often fail and flooding occurs along
with other attendant problems which require costly mainte- -
nance to remedy.
Such a settling problem is solved by use of the
present pipe joint which is designed to slip sufficiently to
compensate for any reasonable amount of settling while still
maintaining a fluidtight connection between the pipe sections.
More specifically, a device according to the present inven-
tion may be defined as a contrac-tion joint for connecting
aligned sections of pipe which joint comprises inner and
outer sleevRs having opposite ends adapted to be secured to
the pipe sections, a first guide member at a lower end of
the inner sleeve, a second guide member at an upper end of
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the outer sleeve, said first and second guide members
slidably and telescopically supporting the inner and suter
sleeve for coaxial movement between an expanded position and
a contracted position, said inner and outer sleeves being
radially spaced apart to provide an annular chamber between
said sleeves and the first and second guide members, and
sealing means contained within the annular chamber having
rolling contact with opposing surfaces of the inner and
outer sleeves between the first and second guide members as
said sleeves move between the expanded position and the
contracted position.
In drawings which illustrate a preferred embodi-
ment of the invention,
Figure 1 is an elevational view, part in section,
showing the present contraction joint in an extended position,
Figure 2 is an enlarged vertical section of the
joint in a fully contracted position, and
Figure 3 is a horizontal section taken on the line
3-3 of Figure 2.
Referring to the drawings, the numeral 10 in-
dicates generally a contraction joint constructed in accor-
dance with the present invention. The joint 10 is shown in
Figure 1 used to provide a connection between two pipe
sections 12 and 14. These pipe sections are assumed to be
parts of a vertically standirlg soil pipe installed in an
apartment building of wood frame construction since such
buildings are subject to a considerable amount of settling
which is the cause of failure in conventional joints. It
should be noted that most building codes require that soil
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pipes and the jolnt itself be made of cast iron for dura-
bility and strenyth.
The cast iron joint 10 is formed of outer and
inner sleeves 20 and 21 which have lower and upper ends 22
and 23 respectively. Conventional flange couplings 24 and
25 or the like may be used to connect the ends 22 and 23 of
the sleeves to the adjoining ends of the pipe sections.
This type of connection secures each sleeve against axial
movement relative to the adjoining pipe sections and, of
course, provides a fluidtight seal therebetween.
As shown in Figure 2, the cylindrical outer sleeve
20 is reduced in diameter near its lower end to provide an
inwardly and downwardly tapering seat 26 on the inside of
the sleeve. The inner sleeve 21 has an integral guide
flange 28 at lower end 29 of the sleeve and this end is
bevelled to provide a tapered shoulder 31 conforming to the
tapered seat 26.
Upper end 33 of the outer sleeve is fitted with a
guide ring 35. This guide ring is tapered in cross section
so as to fit fairly snuggly between the two sleeves of the
contraction joint. Set screws 36 (Figures 2 and 3) secure
the guide ring to the upper end 33 of the outer sleeve.
The two sleeves of the joint 10 are thus spaced
apart to provide an annular chamber 38 which extends between
the guide flange 28 and the guide ring 35. It will be noted
that the sleeves 20 and 21 have opposing surfaces 40 and 41
which are very rough as would be expected of cast iron so
that an exceptionally tough and durable sealing arrangement
is required for the chamber 38.
Such an arrangement is provided by means of rubber
or Neoprene O-rings 45 which are sliyhtly oversize relative
to the space which they must occupy between the opposing
surfaces 40 and 41. The sealing rings 45 are forced into
the chamber 38 before the guide 35 is fitted in place of
course, and the O-rings must be compressed to some extent in
order to enter the chamber whereupon they assume the oval
shape which is shown in Figure 2. secause of this size and
shape of the O-rings, these sealing members roll on the
surfaces 40 and 41 whenever the telescopic sleeves are moved
longitudinally with respect to one another. Thus, a tight
and effective seal is provided by the O-rings 45 which have
the capacity of moving lengthwise of the annular chamber 38.
Figure 1 shows the compression joint 10 fully
extended or expanded as it would be when first installed in
a building. As settling occurs in that building, the
sleeves teiescope eventually to reach the fully compressed
or contracted position shown in Figure 2 where the tapered
shoulder 31 comes into contact with the tapered seat 26.
Water flowing down the pipe carries a certain amount of
debris such as paper and rags which tends to hang up on any
obstruction and eventually to clog the pipe~ However, the
tapered shoulder and seat in the present joint prevents any
such build up regardless of the position of the inner sleeve
within the outer sleeve. The guide members 28 and 35 keep
these sleeves coaxially aligned and sliding smoothly as the
sleeves move longitudinally relative to one another and this
is achieved even when the pipe sections 12 and 14 are not
too accurately aligned as often is the case. Furthermore,
the guide members maintain the spacing between the opposing
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surfaces 40 and 41 of the sleeves and this prevents damage
to the O-rings 45 as they roll between the roughened surfaces
of the cast iron joint. The rouyhened surfaces 40 and 41
impart a rolling action to the O-rings without wearing the
surfaces of those sealing members to any appreciable extent
and do so normally while maintaining the vertical spacing
between the rings and, at the same time, the rings provide a
long lasting and fluidtight sealing action between the
relatively moving sleeves. Should the joint 10 be subjected
to some unusual force tending to pull the sleeves apart, the
O-rings are locked between the guide flange 28 and the guide
ring 35 and those members co-operate to prevent the sleeves
from separating completely.
