HYDRAULIC CYLINDER CONTAMINATION PREVENTION SYSTEM

SYSTEME ANTICONTAMINATION POUR VERIN HYDRAULIQUE

English Abstract

A hydraulic cylinder contamination prevention system for preventing large and
small contaminants from entering
into a hydraulic cylinder, including a hydraulic cylinder rod cover for
underwater use with at least one automatic valve for preventing
water circulation between the outside environment and the enclosed environment
of the cylinder rod cover when the cylinder
is stationary, egress of water from the cylinder rod cover when the cylinder
is retracted, and ingress of water into the cylinder
rod cover when cylinder is extended, and an external and abrasive cylinder rod
scrubber.

French Abstract

L'invention concerne un système anticontamination pour vérin hydraulique servant à empêcher des contaminants de grande et de petite dimension de pénétrer dans un vérin hydraulique, comprenant un couvre-tige de vérin hydraulique destiné à une utilisation sous-marine et doté d'au moins un clapet automatique servant à empêcher toute circulation d'eau entre l'environnement extérieur et l'environnement fermé du couvre-tige de vérin lorsque le vérin est immobile, la sortie d'eau du couvre-tige de vérin lorsque le vérin est rétracté et l'entrée d'eau dans le couvre-tige de vérin lorsque le vérin est déployé, ainsi qu'un nettoyeur externe abrasif de tige de vérin.

Claims

CLAIMS:
1. A submersible hydraulic cylinder contamination prevention system for use
with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising
an external and
abrasive cylinder rod scrubber having a first attachment portion configured to
be clamped to the
cylinder barrel and a second scrubbing portion sized and configured to extend
around and
engage the cylinder shaft.
2. A submersible hydraulic cylinder contamination prevention system for use
with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising
an external and
abrasive cylinder rod scrubber having a first attachment portion configured to
be clamped to the
cylinder barrel and a second scrubbing portion sized and configured to extend
around and
engage the cylinder shaft, wherein the first portion of the cylinder rod
scrubber has a plurality of
spaced apart legs configured to be spaced apart around the cylinder barrel.
3. A submersible hydraulic cylinder contamination prevention system for use
with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising
an external and
abrasive cylinder rod scrubber having a first attachment portion configured to
be clamped to the
cylinder barrel and a second scrubbing portion sized and configured to extend
around and
engage the cylinder shaft, the second portion having opposing first and second
diagonally
angled ends which when the second portion is extending around the cylinder
shaft mate with
each other.
4. A submersible hydraulic cylinder contamination prevention system for use
with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising
an external and
abrasive cylinder rod scrubber having a first attachment portion configured to
be clamped to the
cylinder barrel and a second scrubbing portion sized and configured to extend
around and
engage the cylinder shaft, wherein the cylinder rod scrubber is made of a non-
metallic material.
5. A submersible hydraulic cylinder contamination prevention system for use
with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising
an external and
abrasive cylinder rod scrubber having a first attachment portion configured to
be clamped to the
cylinder barrel and a second scrubbing portion sized and configured to extend
around and
engage the cylinder shaft, wherein the cylinder rod scrubber is manufactured
from a flat
material and sufficiently flexible to be wrapped around the cylinder shaft.
9

6. A submersible hydraulic cylinder contamination prevention system for use
with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising:
a submersible hydraulic cylinder rod cover defining an interior space sized to
at least
partially receive the hydraulic cylinder therein and having at least one
automatic valve
configured to prevent water circulation between the outside environment and
the space within
the cylinder rod cover when the cylinder is stationary, egress of water from
the space within the
cylinder rod cover when the cylinder is retracted, and ingress of water into
the space within the
cylinder rod cover when the cylinder rod is extended.
7. The submersible hydraulic cylinder contamination prevention system of
claim 6
wherein the hydraulic cylinder rod cover has a bellows shape.
8. The submersible hydraulic cylinder contamination prevention system of
claim 6
wherein the hydraulic cylinder rod cover is made of a rubber material.
9. A submersible hydraulic cylinder contamination prevention system for use
with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, where the
cylinder shaft has a
hole sized to receive a pin, comprising:
a submersible hydraulic cylinder rod cover defining an interior space sized to
at least
partially receive the hydraulic cylinder therein and having at least one
automatic valve
configured to prevent water circulation between the outside environment and
the space within
the cylinder rod cover when the cylinder is stationary, and to allow egress of
water from the
space within the cylinder rod cover when the cylinder is retracted, and
ingress of water into the
space within the cylinder rod cover when the cylinder rod is extended, wherein
the hydraulic
cylinder rod cover has a hole to allow the pin to pass therethrough and into
the cylinder shaft
hole.
10. A submersible hydraulic cylinder contamination prevention system for
use with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, where the
cylinder barrel has a
fluid port at an end thereof toward the cylinder shaft, comprising:
a submersible hydraulic cylinder rod cover defining an interior space sized to
at least
partially receive the hydraulic cylinder therein and having at least one
automatic valve
configured to prevent water circulation between the outside environment and
the space within
the cylinder rod cover when the cylinder is stationary, and to allow egress of
water from the
space within the cylinder rod cover when the cylinder is retracted, and
ingress of water into the
space within the cylinder rod cover when the cylinder rod is extended, wherein
the cylinder rod
cover has an end portion sized and shaped to extend over the end portion of
the cylinder barrel
with an opening sized and positioned therein to allow the fluid port to extend
therethrough.

11. A submersible hydraulic cylinder contamination prevention system for
use with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising:
a submersible hydraulic cylinder rod cover defining an interior space sized to
at least
partially receive the hydraulic cylinder therein and having at least one
automatic valve
configured to prevent water circulation between the outside environment and
the space within
the cylinder rod cover when the cylinder is stationary, and to allow egress of
water from the
space within the cylinder rod cover when the cylinder is retracted, and
ingress of water into the
space within the cylinder rod cover when the cylinder rod is extended, and
further including an
external and abrasive cylinder rod scrubber having a first attachment portion
configured to be
attached to the cylinder barrel and a second scrubbing portion sized and
configured to extend
around and engage the cylinder shaft.
12. The submersible hydraulic cylinder contamination prevention system of
claim 11
wherein the first portion of the cylinder rod scrubber has a plurality of
spaced apart legs
configured to be spaced apart around the cylinder barrel.
13. The submersible hydraulic cylinder contamination prevention system of
claim 11
wherein the second portion has opposing first and second diagonally angled
ends which when
the second portion is extending around the cylinder shaft mate with each
other.
14. A submersible hydraulic cylinder contamination prevention system for
use with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising:
a hydraulic cylinder rod cover for underwater use defining an interior space
sized to at
least partially receive the hydraulic cylinder therein; and
an external and abrasive cylinder rod scrubber configured to attach to the
cylinder barrel
and extend around and engage the cylinder shaft.
15. The hydraulic cylinder contamination prevention system of claim 14
wherein said
cylinder rod cover is made from a rubber material.
16. A submersible hydraulic cylinder contamination prevention system for
use with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising:
a hydraulic cylinder rod cover for underwater use defining an interior space
sized to at
least partially receive the hydraulic cylinder therein; and
an external and abrasive cylinder rod scrubber configured to attach to the
cylinder barrel
and extend around and engage the cylinder shaft, wherein the hydraulic
cylinder rod cover has
at least one automatic valve configured to prevent water circulation between
the outside
environment and the enclosed environment within the cylinder rod cover when
the cylinder is
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stationary, and to allow egress of water from the cylinder rod cover when the
cylinder rod is
retracted, and ingress of water into the cylinder rod cover when the cylinder
rod is extended.
17. A submersible hydraulic cylinder contamination prevention system for
use with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising:
a hydraulic cylinder rod cover for underwater use defining an interior space
sized to at
least partially receive the hydraulic cylinder therein; and
an external and abrasive cylinder rod scrubber configured to attach to the
cylinder barrel
and extend around and engage the cylinder shaft, wherein the abrasive cylinder
rod scrubber is
made from a non-metallic material.
18. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft; and
an external and abrasive cylinder rod scrubber having a first attachment
portion
attached to the cylinder barrel and a second scrubbing portion extending
around and engaging
the cylinder shaft.
19. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft;
an external and abrasive cylinder rod scrubber having a first attachment
portion
attached to the cylinder barrel and a second scrubbing portion extending
around and engaging
the cylinder shaft, the first portion of the cylinder rod scrubber having a
plurality of legs
positioned at spaced apart locations around the cylinder barrel; and
a clamp clamping the plurality of legs to the cylinder barrel.
20. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft; and
an external and abrasive cylinder rod scrubber having a first attachment
portion
attached to the cylinder barrel and a second scrubbing portion extending
around and engaging
the cylinder shaft, the second portion having opposing first and second
diagonally angled ends
which mate with each other.
21. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft; and
an external and abrasive cylinder rod scrubber having a first attachment
portion
attached to the cylinder barrel and a second scrubbing portion extending
around and engaging
the cylinder shaft, wherein the cylinder rod scrubber is made of a flat, non-
metallic, flexible
material and is wrapped around the cylinder shaft.
12

22. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft; and
a submersible hydraulic cylinder rod cover defining an interior space at least
partially
receiving the hydraulic cylinder therein and having at least one automatic
valve configured to
prevent water circulation between the outside environment and the space within
the cylinder
rod cover when the cylinder is stationary, egress of water from the space
within the cylinder rod
cover when the cylinder is retracted, and ingress of water into the space
within the cylinder rod
cover when the cylinder rod is extended.
23. The submersible hydraulic cylinder contamination prevention system of
claim 22
wherein the hydraulic cylinder rod cover has a first end portion attached to
the cylinder barrel
and a second end portion attached to the cylinder rod for movement therewith.
24. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft, the
cylinder shaft
having a hole with a pin received therein; and
a submersible hydraulic cylinder rod cover defining an interior space at least
partially
receiving the hydraulic cylinder therein and having at least one automatic
valve configured to
prevent water circulation between the outside environment and the space within
the cylinder
rod cover when the cylinder is stationary, and to allow egress of water from
the space within the
cylinder rod cover when the cylinder is retracted, and ingress of water into
the space within the
cylinder rod cover when the cylinder rod is extended, the hydraulic cylinder
rod cover having a
hole through which the pin to extends.
25. The submersible hydraulic cylinder contamination prevention system of
claim 24
wherein the hydraulic cylinder rod cover has a first end portion attached to
the cylinder barrel
and a second end portion attached to the cylinder rod for movement therewith.
26. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft; and
a submersible hydraulic cylinder rod cover defining an interior space at least
partially
receiving the hydraulic cylinder therein and having at least one automatic
valve configured to
prevent water circulation between the outside environment and the space within
the cylinder
rod cover when the cylinder is stationary, and to allow egress of water from
the space within the
cylinder rod cover when the cylinder is retracted, and ingress of water into
the space within the
cylinder rod cover when the cylinder rod is extended, wherein the hydraulic
cylinder rod cover
has a bellows shape.
27. A submersible hydraulic cylinder contamination prevention system,
comprising:
13

a hydraulic cylinder having a cylinder barrel and a cylinder shaft; and
a submersible hydraulic cylinder rod cover defining an interior space at least
partially
receiving the hydraulic cylinder therein and having at least one automatic
valve configured to
prevent water circulation between the outside environment and the space within
the cylinder
rod cover when the cylinder is stationary, and to allow egress of water from
the space within the
cylinder rod cover when the cylinder is retracted, and ingress of water into
the space within the
cylinder rod cover when the cylinder rod is extended, wherein the cylinder
barrel has a fluid port
at an end thereof toward the cylinder shaft, and the hydraulic cylinder rod
cover has an end
portion extending over the end portion of the cylinder barrel, the end portion
of the hydraulic rod
cover having an opening into which the fluid port extends.
28. A submersible hydraulic cylinder contamination prevention system,
comprising:
a hydraulic cylinder having a cylinder barrel and a cylinder shaft;
a submersible hydraulic cylinder rod cover defining an interior space at least
partially
receiving the hydraulic cylinder therein and having at least one automatic
valve configured to
prevent water circulation between the outside environment and the space within
the cylinder
rod cover when the cylinder is stationary, and to allow egress of water from
the space within the
cylinder rod cover when the cylinder is retracted, and ingress of water into
the space within the
cylinder rod cover when the cylinder rod is extended; and
an external and abrasive cylinder rod scrubber having a first attachment
portion
attached to the cylinder barrel and a second scrubbing portion extending
around and engaging
the cylinder shaft.
29. The submersible hydraulic cylinder contamination prevention system of
claim 28
wherein the first portion of the cylinder rod scrubber has a plurality of
spaced apart legs
positioned at spaced apart locations around the cylinder barrel.
30. The submersible hydraulic cylinder contamination prevention system of
claim 28
wherein the second portion of the cylinder rod scrubber has opposing first and
second
diagonally angled ends which mate with each other.
31. A submersible hydraulic cylinder contamination prevention system for
use with a
hydraulic cylinder having a cylinder barrel and a cylinder shaft, comprising:
a submersible hydraulic cylinder rod cover defining an interior space sized to
at least
partially receive the hydraulic cylinder therein and having at least one
automatic valve
configured to prevent water circulation between the outside environment and
the space within
the cylinder rod cover when the cylinder is stationary, and to allow egress of
water from the
space within the cylinder rod cover when the cylinder shaft is retracted, and
ingress of water
into the space within the cylinder rod cover when the cylinder shaft is
extended, wherein a first
14

end portion of the cylinder rod cover is attached to the cylinder barrel and
an opposite second
end portion of the cylinder rod cover is attached to the cylinder shaft, and
the cylinder rod cover
longitudinally contracts and expands as the cylinder shaft retracts and
extends, respectively,
and further including a plurality of guides positioned within the interior
space of the cylinder rod
cover, each guide including a central aperture through which the cylinder
shaft is extendable
when positioned within the cylinder rod cover, each guide further including at
least one hole for
the flow of water within the cylinder rod cover therethrough as the cylinder
shaft retracts and
extends.
32. The submersible hydraulic cylinder contamination prevention system of
claim 31
wherein the guides are coupled to the cylinder rod cover for travel therewith
as the cylinder rod
cover longitudinally contracts and expands
33. The submersible hydraulic cylinder contamination prevention system of
claim 32
further including an abrasive rod scrubber attached to each of the guides for
engagement with
the cylinder shaft when positioned within the cylinder rod cover and extending
through the
central aperture of the guide as the guide moves along the cylinder shaft as
the cylinder rod
cover longitudinally contracts and expands and the cylinder shaft retracts and
extends,
respectively.
34. The submersible hydraulic cylinder contamination prevention system of
claim 33
wherein the abrasive rod scrubber is an abrasive ring member extending about
the central
aperture of the guide.
35. The submersible hydraulic cylinder contamination prevention system of
claim 34
wherein the abrasive ring member extends fully around the central aperture of
the guide and
the cylinder shaft when extending therethrough.
36. The submersible hydraulic cylinder contamination prevention system of
claim 31
wherein the cylinder rod cover is a flexible corrugated boot with each of the
guides nested
internally within a different ridge of the corrugated boot.
37. The submersible hydraulic cylinder contamination prevention system of
claim 31
wherein the hydraulic cylinder rod cover is made of a rubber material.
38. The submersible hydraulic cylinder contamination prevention system of
claim 31
further including an external and abrasive cylinder rod scrubber configured to
attach to the
cylinder barrel and extend around and engage the cylinder shaft.

39. The submersible hydraulic cylinder contamination prevention system of
claim 38
wherein the cylinder rod cover is made from a rubber material.
40. The submersible hydraulic cylinder contamination prevention system of
claim 31
further including an external and abrasive cylinder rod scrubber having a
first attachment
portion attached to the cylinder barrel and a second scrubbing portion
extending around and
engaging the cylinder shaft.
16

Description

CA 02750606 2013-11-13
HYDRAULIC CYLINDER CONTAMINATION PREVENTION SYSTEM
Field of Invention
The invention generally relates to an apparatus and method for preventing
contamination from entering a hydraulic cylinder in an underwater environment.
Background of Invention
The use of hydraulic cylinders for lifting heavy loads is well known. A common
problem in the use of hydraulic cylinders in dirty or underwater environments
is
contaminants entering into the hydraulic system and causing problems with the
hydraulic pumps. Contaminants such as mud, dirt, marine growth, and mineral
deposits build up on the cylinder rod and are dragged through the seals of the
cylinder
barrel. One of the most challenging contaminants are mineral deposits because
they
are microscopic particles diluted into water. As water flows around the
cylinder rod
minerals such as calcium carbonate attach to the cylinder rod.
There are many solutions for protecting a hydraulic cylinder shaft in above
water
applications, but most will not work in an underwater application for various
reasons
that will be described. The most common cylinder rod protection is a boot that
prevents contaminants from contacting the rod of a cylinder. These can be seen
in use
on motorcycle shock absorbers, heavy machinery and more. The main problem with
using a standard boot on an underwater cylinder is the change in volume inside
the
cylinder boot when the cylinder expands and contracts. Standard cylinder boots
allow
air to free flow in and out of the boot such as in US Patent 6932356 to
Gloaguen. If the
standard cylinder boot is used underwater the boot will implode while the
cylinder
extends because the cylinder boot cannot suck in water at same rate it can
suck air in.
When the cylinder retracts the cylinder boot will balloon because the cylinder
boot
cannot push water out as fast as it can push air out. A simple solution to
allowing water
to flow in and out of the cylinder boot would be to add a large vent hole. The
cylinder
boot with a large vent hole would work to keep large contaminants off of the
cylinder
rod, but because the hole in the cylinder boot allows water to free flow in
and out of the
cylinder boot unlimited minerals can float into the cylinder boot and attach
to the
cylinder rod still leaving a contamination problem.
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CA 02750606 2013-11-13
Another common device used to prevent contamination entering into a hydraulic
cylinder is an internal cylinder scrapper. US Patent 4577363 to Wyse, US
Patent
4461486 to Tregonning and US Patent 6047970 to Friend are examples of cylinder
scrapers. Internal cylinder scrappers are knife edged rings, made from
stainless steel or
bronze, that are fixed into a cylinder head above the cylinder seals. Internal
cylinder
scrappers do a good job of removing large marine growth like barnacles, but
they allow
small particles like mineral deposits or marine growth residue to pass through
into the
cylinder.
Accordingly, there is a need in the art for a cylinder contamination
protection
system suitable for underwater use that protects a cylinder from one or both
of large
contaminants such as mud, dirt and marine growth, and small contaminants such
as
mineral deposits and marine growth residues.
Summary of the Invention
The disclosed embodiments of the present invention include a hydraulic
cylinder
contamination prevention system that prevents one or both of large and small
contaminants from entering into the hydraulic cylinder. The hydraulic cylinder
contamination prevention system may include a hydraulic cylinder rod cover for
underwater use with at least one automatic valve for preventing water
circulation
between the outside environment and the enclosed environment of the cylinder
rod
cover when the cylinder is stationary, egress of water from the cylinder rod
cover when
the cylinder is retracted, and ingress of water into the cylinder rod cover
when cylinder
is extended. The hydraulic cylinder contamination prevention system may
include an
external and abrasive cylinder rod scrubber.
The cylinder boot with at least one automatic valve serves two purposes; it
protects the cylinder rod from large contaminant build up like mud, barnacles,
muscles,
and other marine growth and it eliminates the free flow of mineral filled
water around
the cylinder rod, thus greatly reducing and possibly eliminating the mineral
build up on
the cylinder rod. The preferred embodiment of the automatic valve of the
cylinder rod
cover is a rubber flapper valve with a diameter of at least 3/8 inch. The
rubber flapper
valve seals on itself while the cylinder is stationary. When the cylinder is
retracted or
extended the force of the water entering in or exhausting from the cylinder
rod cover
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CA 02750606 2013-11-13
pushes open the flapper valve. The open flapper valve allows water to flow in
and out
of the cylinder rod cover without causing implosion or ballooning of the
cylinder rod
cover when the cylinder is extending or retracting. The automatic valve may
also be a
slit in the flexible material of the hydraulic cylinder rod cover such as a
slit in a rubber
cylinder boot.
The preferred embodiment of the cylinder rod cover is a corrugated shape
similar to a bellows. The number and size of the corrugations is selected to
allow
marine growth on the cylinder rod cover while not inhibiting the expansion and
contraction of the corrugated cylinder rod cover. The cylinder rod cover is
preferably be
made of a durable material such as EPDM rubber so the marine growth does not
cause
tearing. The durometer of the material is also to be considered since too soft
durometer material will allow ballooning of the cylinder rod cover and too
hard a
durometer material will cause the cylinder rod cover to buckle. Through
testing a
preferred durometer is around Shore 80A.
If some small contaminants are able to attach to the cylinder rod the external
and
abrasive cylinder rod scrubber removes the remaining contaminants from the
cylinder
rod. The preferred embodiment of the cylinder rod scrubber is cut out of an
abrasive
scotch-brite type pad and then wrapped around the cylinder rod and clamped to
the
cylinder barrel. The cylinder rod slides through the abrasive cylinder rod
scrubber
removing any small contaminant build up.
Preferably, the cylinder rod cover and cylinder rod scrubber will be used
together, but in some cases the cylinder rod cover and cylinder rod scrubber
can be
used separate of each other and perform their singular functions. An example
of this
would be a location with high marine growth, but low mineral content in the
water (such
as in salt water); in this case someone may choose to use just the cylinder
rod cover.
Another example would be a low marine growth low mineral content water
location
(such as in a fresh water lake); in this case someone may choose to use just
the
cylinder rod scrubber to keep the cylinder rod clean.
Brief Description of the Drawings
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CA 02750606 2013-11-13
The foregoing aspects and many of the attendant advantages of this invention
will become more readily appreciated as the same becomes better understood by
reference to the following detailed description, when taken in conjunction
with the
accompanying drawings, which are schematic, and not to scale, wherein:
FIGURE 1 is an isometric view of a cylinder boot.
FIGURE 2 is a transparent isometric view of the cylinder boot.
FIGURE 3 is a side view of the cylinder boot.
FIGURE 4 is an isometric view of the cylinder boot mounted to a cylinder.
FIGURE 5 is an isometric view of a boat lift with an extend cylinder with a
boot
attached thereto.
FIGURE 6 is an isometric view of the boat lift of FIGURE 5 with the cylinder
retracted.
FIGURE 7 is a side view of the cylinder boot with an abrasive ring.
FIGURE 8 is an isometric view of a second embodiment of the cylinder boot.
FIGURE 9 is a second embodiment of the abrasive ring.
FIGURE 10 is a side view of a cylinder with the abrasive ring of FIGURE 9
shown attached to the cylinder.
FIGURE 11 is a cross-sectional side view of the cylinder of FIGURE 10 with a
cylinder boot and abrasive ring attached.
FIGURE 12 is a cross-sectional side view of an alternative cylinder boot
extending over a hydraulic fluid port of a cylinder.
Detailed Description of the Preferred Embodiment
The following descriptions illustrate aspects of the invention, and identify
certain
preferred embodiments of these aspects. The descriptions are not intended to
be
exhaustive, but rather to inform and teach a person of skill in the art who
will come to
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CA 02750606 2013-11-13
appreciate more fully other aspects, equivalents, and possibilities presented,
and hence
the scope of the invention is set forth in the claims, which alone limit its
scope.
Several details of the preferred embodiments are set forth in the following
description: Figures 1 through 12 provide a thorough understanding of such
embodiments. One skilled in the art will understand that the present invention
may be
practiced without several of the details described herein. In the following
description of
the embodiments, it is understood that the figures related to the various
embodiments
are not to be interpreted as conveying any specific or relative physical
dimension, and
that specific or relative dimensions related to the various embodiments, if
stated, are
not be considered limiting unless the claims state otherwise.
Figure 1 shows an isometric view of a preferred embodiment of a cylinder boot
10 comprising of a flexible corrugated cylinder 11. The cylinder boot 10 uses
a cylinder
barrel attachment 12 which may be a clamp or zip tie to hold it fast to a
cylinder barrel
41 of a hydraulic cylinder 40 such as shown in Figure 4. The cylinder boot 10
also
includes cylinder rod attachment 13 which is an end portion of the cylinder
boot which
fits more tightly around a cylinder shaft or rod 42 such as shown in Figure 4
to hold the
end portion fast to the cylinder rod so that the end portion of the cylinder
boot attached
to the cylinder rod moves with the cylinder rod as it extends from and
retracts into the
cylinder barrel 41. In the illustrated embodiment, the cylinder rod attachment
13
includes a pin hole 16 that is sized and located to coincide with a pin hole
in the
cylinder rod to allow insertion of a pin (not shown) through the pin hole 16
and the pin
hole of the cylinder rod and thereby attach the end of the cylinder rod 42 to
the
mechanism it moves. When the pin is inserted into the pin hole 16 and the pin
hole in
the cylinder rod, the end portion of the cylinder boot 10 is securely affixed
to the
cylinder rod 42 and held in place during operation of the hydraulic cylinder
40.
The cylinder boot 10 also includes a duck bill vent 14 and flapper vent 15.
Duck
bill vent 14 and flapper vent 15 of cylinder boot 10 allow water to flow in
and out of
cylinder boot 10 when it travels between extended position "A" (shown in
Figure 5) and
collapsed position "B" (shown in Figure 6). When cylinder boot 10 is
stationary, duck
bill vent 14 and flapper vent 15 keep water from free flowing through cylinder
boot 10.
The cylinder boot 10 may be made of a rubber material. Alternative venting may
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CA 02750606 2013-11-13
include a slit in the flexible material of the cylinder boot 10. Although a
slit would allow
some leakage since not a perfect seal, it would serve the same purpose and
accomplishes the desired function. In the preferred embodiments passive acting
valves
are used so their action is automatic and require no external control or power
to
operate, and simply respond to the water pressure applied thereto during
operation of
the cylinder boot 10 and the water flow.
Figure 2 is a transparent isometric view of the cylinder boot 10 further
comprising
interiorly positioned collapsing guides 21. Collapsing guides 21 have holes 22
to allow
water to flow through.
Figure 3 is a side cross-sectional view of cylinder boot 10 showing collapsing
guides 21 nesting in the corrugated flaps of flexible corrugated cylinder 11.
Figure 4 is an isometric view of cylinder 40 illustrating its cylinder barrel
41 and
cylinder rod 42, shown with cylinder boot 10 protecting cylinder rod 42. As
discussed
above, cylinder boot 10 attaches to cylinder 40 at cylinder barrel 41 with
cylinder barrel
attachment 12 and at cylinder rod 42 with cylinder rod attachment 13.
Collapsing
guides 21 of cylinder boot 10 slide over cylinder rod 42 to allow cylinder
boot 10 to
collapse evenly when cylinder 40 is drawn into the collapsed position "B" (see
Figure 6).
The cylinder barrel 41 of cylinder 40 includes two hydraulic fluid ports 43
and 44 to
control fluid powered operation of the cylinder. In the embodiment of Figure
4, the
cylinder barrel attachment 12 is located longitudinally outward of the fluid
port 43 at the
end of the cylinder barrel 41 from which the cylinder rod 42 extends.
Figure 5 is a partial isometric view of a boatlift 50 with cylinder 40 in the
extended position "A" with the cylinder rod 42 extended, with the cylinder
boot 10
protecting cylinder rod 42 from the marine environment.
Figure 6 is a partial isometric view of boatlift 50 with cylinder 40 in the
collapsed
position "B" with the cylinder rod 42 retracted, again with the cylinder boot
10
protecting cylinder rod 42 from the marine environment.
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Figure 7 is a side cross-sectional view of cylinder boot 10 showing collapsing
guides 21 nesting in the corrugated flaps of flexible corrugated cylinder 11.
The rear
collapsing guide 21 has abrasive ring 71 attached which serves as a cylinder
rod
scrubber. Abrasive ring 71 fits tightly to cylinder rod 42 shown in Figure 4,
to clean off
any contamination attached to the cylinder rod 42.
Figure 8 shows an isometric view of a second preferred embodiment of the
cylinder boot 10 comprising of a flexible corrugated cylinder 11, cylinder
barrel
attachment 12, cylinder rod attachment 13, pin hole 16, and flapper vent 15.
Flapper
vent 15 of cylinder boot 10 allows water to flow in and out of cylinder boot
10 when it
travels between extended position "A" (shown in Figure 5) and collapsed
position "B"
(shown in Figure6). When cylinder boot 10 of Figure 8 is stationary, duck bill
vent 14
and flapper vent 15 keep water from free flowing through cylinder boot 10.
Figure 9 is a second embodiment showing an alternative abrasive ring 90. The
abrasive ring 90 is preferably manufactured from a flat stock material by
cutting out the
design illustrated in Figure 9 with a scrubbing head portion including a pair
of opposite
diagonal cuts 91 which mate together in opposing positions when wrapped around
the
cylinder rod 42 when installed on the cylinder rod, and a scrubbing surface 93
that
engages the cylinder rod as it extends and retracts to clean the cylinder rod.
The
cylinder rod 42 slides through the abrasive ring 90 which scrubs and thereby
removes
any small contaminant build up. The abrasive ring 90 includes a pair of
attachment
legs 92 that when the installed abrasive ring is wrapped around the cylinder
rod 42 are
positioned on opposite sides of the cylinder barrel 41 as shown in Figure 10.
The legs
92 are spaced apart sufficiently to be positioned with the fluid port 43
projecting
therebetween. The preferred embodiment of the abrasive ring 90 is cut out of
an
abrasive scotch-brite type pad and then wrapped around cylinder barrel 41 and
cylinder
rod 42, and clamped to thereto as will be described below.
Figure 10 is a side view of cylinder 40 with abrasive ring 90 of Figure 9
clamped
to cylinder rod 42 with scrubbing surface 93 thereof extending around the
cylinder rod
and clamped thereto by zip ties 111 thereby holding the scrubbing surface in
tight
engagement with the cylinder rod. The legs 92 of the abrasive ring 90 are
shown
7

CA 02750606 2013-11-13
clamped to cylinder barrel 41 with a zip tie 112. With this arrangement, the
cylinder rod
42 can slide through scrubbing surface 93 to clean off mineral deposits such
as calcium
carbonate.
Figure 11 is a side cross-sectional view of cylinder 40 of Figure 9 with
cylinder
boot 10 and abrasive ring 90 attached.
Figure 12 is a side cross-sectional view of cylinder 40 of Figure 9 using an
alternative cylinder boot 10 with an end portion that extends over the fluid
port 43 of the
cylinder barrel 41 which has a hole or cutout sized and positioned to permit
the fluid
port 43 to extend therethrough. In this embodiment the fluid port 43 retains
the cylinder
boot 10 attached to the cylinder barrel 41 with or without the use of the zip
time 112.
8

Representative Drawing