[0001] This invention relates to retention devices for removably retaining an object in
a passage or cavity, and is intended particularly though not solely to provide a device
which can be removably retained in a body cavity or passage, such as within the digestive
or reproductive systems of an animal, for example for veterinary or reproduction control
purposes.
[0002] It is an object of the invention to provide a retention device for removable retention
in a passage or cavity which will at least provide the public with a useful choice.
[0003] Accordingly, in one aspect, the invention consists in a retention device for removable
retention in a passage or cavity, comprising: a pair of bifurcated members each having
a pair of resilient movable branch members the branch members of one bifurcated member
being movably connected to the branch members of the other bifurcated member to form
a diamond in one configuration of the pair; and an operating member connected or associated
with one of said bifurcated members; said bifurcated members being displaceable between
at least two relative configurations, a first configuration in which a first one of
said bifurcated members is substantially nested inside the other of said bifurcated
members for insertion purposes, and a second configuration being a laterally extended
configuration in which parts of said bifurcated members are resiliently expanded to
bear in use against walls of a selected passage or cavity to retain the device therein
and said device is laterally compressible so as to be insertable into and removable
from said passage or cavity, said device being displaceable between said configurations
by use of said operating member.
[0004] To those skilled in the art to which the invention relates, many changes in construction
and widely differing embodiments and applications of the invention will suggest themselves
without departing from the scope of the invention as defined in the appended claims.
The disclosures and the descriptions herein are purely illustrative and are not intended
to be in any sense limiting.
[0005] One preferred form of the invention will now be described with reference to the accompanying
drawings, in which
Figure 1 shows a device in accordance with the invention in an open or diamond configuration;
Figure 2 shows the device of Figure 1 in an insertion configuration when laterally
compressed for insertion into a selected passage or cavity; and
Figure 3 shows the device of Figures 1 and 2 in a retention configuration so as to
be retained in the passage or cavity.
[0006] Referring now to the figures, a device for retention in a cavity or passage, such
as in a body cavity or passage of animals such as cattle or pigs, is provided and
shown in Figure 1. The retention device comprises a pair of resilient movable bifurcated
members, for example "V" or "U" shaped members 1 and 2 which are movably preferably
resiliently interconnected at the open ends of the "V" or "U", for example by interconnections
3; and an operating member 4 is attached to or demountably associated with the junction
or closed end 5 of the bifurcated member 2. Bifurcated member 1 has two preferably
resiliently flexible branches 6, and bifurcated member 2 has two preferably resiliently
flexible branches 8. The branches 6 are resiliently interconnected with one another
at a junction 7 forming the closed end of bifurcated member 1 and the branches 8 are
resiliently interconnected with each other at the junction 5 or closed end of bifurcated
member 2. Branches 8 of bifurcated member 2 are suitably relatively shorter than equivalent
branches 6 of bifurcated member 1 to enable nesting as shown in Figure 2.
[0007] The retention device in use may be associated with or form part of a device for veterinary
purposes and may then include some other functional portion such as a known device
9 having zones impregnated with a particular pharmaceutical to be dispensed to an
animal,and having foldable legs 10 or any other desired functional portion.
[0008] The device may be moulded for example of a suitable plastics material which may be
moulded in the configuration shown in Figure 1 (referred to herein as the second configuration),
and preferably comprises a skeleton 11 of a harder but still flexibly resilient material
such as nylon or polypropeylene onto which a drug carrying matrix 12 of e.g. silicone
or EVA is applied. Such a device 9 is disclosed in Patent Specifications GB2154875A
and US4678463 which are incorporated herein by reference. Parts or all of branches
6 and 8 and parts or all of interconnections 3 are preferably coated with a cushioning
layer 15 which is preferably a continuation of or of the same composition as the drug
carrying matrix 12.
[0009] When it is desired to insert the device into a passage or cavity of an animal eg.
the vagina of a pig, the device may be folded, from the moulded second configuration
shown in Figure 1 in which the interconnection 3 of the bifurcated members 1 and 2
are spaced apart and so that the bifurcated members 1 and 2 are in a diamond configuration
opposite one another into the retention configuration shown in Figure 2 by applying
force to the operating member 5 towards the bifurcated members substantially along
the longitudinal axis of the device, in the direction indicated by the arrow 16, so
that the junction 5 of the bifurcated member 2 is forced towards the junction 7 of
the opposite facing bifurcated member 1. Due to the pivoting and preferably resilience
of the bifurcated members and of the connections 3 and 4 between them, initially the
paired branches of the two bifurcated members are spread apart by application of such
force, and when the relatively shorter branches 8 of member 2 are in line in the space
between the interconnections 3, sprung over that line and nest with the branches 6
of the facing bifurcated member 1, as shown in Figures 2 and 3.
[0010] The parts of the skeleton 11 forming the inter-connecting portions 3 are preferably
provided as outwardly curved strips or portions of resilient material as shown to
facilitate this springing over.
[0011] Once in the insertion configuration shown in Figure 2, the device can be laterally
compressed by pinching them together as indicated by the arrows 16, and the device
9, may also be folded. The entire device may be contained in this folded form in an
applicator eg. of tubular form as shown in GB2154875A, US4678463. The device is then
inserted lengthwise into a selected passage or cavity, for example into a body cavity
of an animal, and the applicator is then withdrawn. The branches 6 and 8 of the bifurcated
members 1 and 2, when in the insertion configuration shown in Figure 2, are biased
to extend laterally from the longitudinal axis of the device, which can be defined
by the longitudinal axis of the operating member 5, as shown in Figure 3. When the
applicator is withdrawn, the branches tend to adopt the laterally extended retention
configuration shown in Figure 3 and the device is thus retained against expulsion
from the passage or cavity by for example muscular contractions, as the bifurcated
members and/or the connecting portion 3 bear against the walls of the passage or cavity
offering resistance to expulsion.
[0012] When it is desired to remove the device, the extended operating member 5 can be grasped
and pulled in the direction indicated by the arrow 12 which reverses the springing
over procedure, the bifurcated members 1 and 2 resuming their open and opposite facing
configuration as shown in Figure 1. Continued pulling on the operating member 5 tends
to lead the device out of the passage or cavity, with extension lengthwise and narrowing
the width of the diamond shape of the retention the device laterally compressing by
closing of the branches 6 and 8 of bifurcated members 1 and 2 towards each other.
[0013] Thus it can be seen that a retention device is provided by the invention which is
readily operated so as to be securely retained in a selected passage or cavity and
which can also be readily converted into a configuration allowing withdrawal from
the passage or cavity. The device is also simple to make and operate.
[0014] The features disclosed in the foregoing description, in the following claims and/or
in the accompanying drawings may, both separately and in any combination thereof,
be material for realising the invention in diverse forms thereof.
1. A retention device for removable retention in a passage or cavity, comprising:
a pair of bifurcated members(1,2) each having a pair of resilient movable branch members(6,8)
characterised in that the branch members(8) of one bifurcated member(2) are movably
connected(3) to the branch members(6) of the other bifurcated member(1) to form a
diamond in one configuration of the pair, said device also having an operating member(4)
connected(5) or associated with one of said bifurcated members, and said device being
further characterised in that said bifurcated members(1,2) are displaceable between
at least two relative configurations, a first configuration in which a first one of
said bifurcated members is substantially nested inside the other of said bifurcated
members for insertion purposes, and a second configuration being said diamond configuration
in which parts of said bifurcated members are resiliently expanded to bear in use
against walls of a selected passage or cavity to retain the device therein and said
device is laterally compressible so as to be insertable into and removable from said
passage or cavity, said device being displaceable between said configurations by use
of said operating member.
2. A retention device as claimed in claim 1 wherein said operating member(4) is connected(5)
or associated with a junction between branches(8) of said one bifurcated member(2)
and the branches(8) of said one bifurcated member(2) are shorter than the branches(6)
of said other bifurcated member(1).
3. A retention device as claimed in claim 1 or claim 2 wherein the flexible movable
connections(3) between said branches(6,8) of said bifurcated members(1,2) are coated
with a cushioning layer(15).
4. A retention device as claimed in any one of the preceding claims wherein said retention
device is associated with or forms part of a device for veterinary purposes.
5. A retention device as claimed in any one of the preceding claims wherein said branches(6,8)
are flexibly resilient.
6. A retention device as claimed in any one of the preceding claims wherein said branch
members(8) of one bifurcated member(2) are resiliently connected(3) to corresponding
branch members(6) of the other bifurcated member(1).