[0001] This invention relates to a scraper for removing calcareous growths, anemones, mussels,
sea-weeds or algae, etc. on flat or arched surfaces.
[0002] There are already known for treating under water or by means of water such flat or
arched surfaces, scouring disks which are provided on the circumference thereof with
knives which extend directly outwards, either in parallel relationship with the plane
of said disk, or at a slight angle with respect to said plane.
[0003] When such disks engage calcareous growths or shells, they are rapidly blocked as
the disk edge is retained by said growths. Indeed the knives used up to now can attack
such growths but to a limited depth. Moreover, the paint coat on said structure to
be scraped is damaged by said knives during the operation, which should be prevented
in most cases.
[0004] The invention has for object to provide a scraper which obviates the drawbacks of
the scouring disks or scrapers known up to now and which also makes it possible then
to loosen calcareous growths with any structure and extent whatsoever from flat or
arched surfaces, and thereby letting undamaged the paint coat on the structures being
treated.
[0005] To obtain such result according to the invention, the scraper is formed according
to the invention by a motor-driven disk with a number radial knives distributed along
the circumference thereof, which knives have a structure allowing bending thereof
along at least two planes, namely that lengthwise symmetry plane wherein the knife
extends and a plane which extends at right angle to said first plane and in parallel
relationship with the disk geometrical axis.
[0006] Other details and advantages of the invention will stand out from the following description,
given by way of non limitative example and with reference to the accompanying drawings,
in which:
Figure 1 is a perspective bottom view of a scraper according to the invention.
Figure 2 shows on another scale, the edge of a scraper or scouring disk fitted with
slantingly-adjusted straight knives.
Figure 3 shows the way a curled knife from the scraper according to the invention,
operates on calcareous growths.
Figure 4 is a front view of a curled knife from the scraper according to the invention,
in a first possible working position.
Figure 5 is a front view of a curled knife from the scraper according to the invention,
in a second possible working position.
Figure 6 shows a curled knife from the scraper according to the invention, in a third
possible working position.
Figures 7 and 8 show a particular embodiment of a knife intended for a scraper according
to the invention.
Figures 9 and 10 pertain to a possible variation of a knife for a scraper according
to the invention.
Figure 11 pertains to a loop-shaped knife which may be considered as a possible embodiment
of the invention.
Figure 12 pertains to particular possible embodiments of knives to be used with a
scraper according to the invention.
Figure 13 pertains to a last possible embodiment.
[0007] The scraper according to the invention is essentially comprised of a disk 1 whereon
a number radial curled knives 2 are secured.
[0008] In a preferred embodiment, the knives 2 are cantilever ones, which means that the
free end thereof does not bear on some surface of disk 1. Other shapes of cantilever
knives are shown in figures 7, 8, 9, 10 and in some way 12.
[0009] Cantilever knives have as compared to loop-shaped knives which bear with both ends
thereof on disk 1 from the scraper, the very large advantage of bending or deflecting
in that location where they engage the surfaces to be cleaned. Such deflection occurs
due to the knives tapering towards the free end thereof or having a thickness which
is progressively reduced towards the free end. Both these features may naturally be
combined.
[0010] Loop-shaped knives are then to be used efficiently but when they have locally a thickness
which gets progressively thinner. At the same time the knife may narrow in the direction
of the contact point with the surface to be cleaned, or narrow in an arbitrary location
as far as this allows the knife deflecting.
[0011] To understand the accurate and efficient working of the scraper according to the
invention, reference will first be made to figure 2 where it is made clear how a disk
3 fitted with flat knives 4 extending outwards along the circumference, is retained
by calcareous growths 5. The knives 4 do indeed enter to a limited depth the grown
mass, but such mass then directly forms an obstacle to disk 3 which can not further
enter or at least but with great difficulty, the growths to be scoured. The drawback
of such scrapers is mostly evident when calcareous growths are being treated. Moreover
such straight knives 4 unavoidably damage the paint coat on the surfaces to be scoured.
This is also a very substantial drawback of scouring disks fitted with said straight-type
knives.
[0012] When using said knives 2, the shells or other calcareous growths, anemones, sea-weeds
and algae are treated in accordance with a completely new principle. Due to the curl
shape of the knives with a cantilever end (figure 3), the disk edge 6 never does engage
the growths or deposits to be removed. Same are continuously attacked by the radially-arranged
curled knives, in such as a way that said growths and deposits continuously break-off
and may be removed from the surface to be scoured without the scraper being hampered
or slowed-down in the movement thereof as shown by arrow 7 (figure 3). Due to the
knife curled shape, there occurs a continuous breaking-off of the growths the uppermost
part of which breaks and is removed, while the paint coat of those surfaces 8 to be
scoured is not attacked. This is not only due to the specific curled shape of said
knives 2, but also to the curved cross-section of the knife which engages that surface
to be cleaned. The fact that the knife thickness progressively decreases either in
the direction of the knife free end, or in the direction of that location where the
knife engages the surface to be cleaned, also plays hereby an essential part.
[0013] When the knives are moved over an obstacle such as a welding seam 9 for example,
said knives also bend as well in the lengthwise symmetry plane of the knife as in
a plane which lies at right angle thereto and extends in parallel relationship with
the geometrical axis of disk 1.
[0014] In figures 4, 5 and 6, the reference numeral 10 shows a surface to be cleaned where
a welding seam 9 is present, or where growths such as as mussels 12 occur. That direction
the knives 2 move along, is shown by arrow 11.
[0015] Excellent results are obtained with cantilever curled knives. The wording "curled"
covers a series possible embodiment shapes figures 1, 3 and 7 to 13 pertain to.
[0016] In figures 7 and 8, a spiral-like curled knife 13, 13' respectively, is shown. With
such knives also, the knife material thickness decreases from the base the knife is
connected to disk 1 with, in the direction of the free end thereof.
[0017]
Figures 9 and 10 pertain to twin-design curled knives 14 and 15 which each meet the
requirement for having a minimum width, preferably in that location where said knives
will meet the highest resistance. The width of such knives also decreases from the
base in the direction of the free end, in the case of cantilever knives as shown in
said figures. It is due to such features as well as to the knives being curved at
least where they engage the surfaces to be cleaned, that the knives can adapt to such
obstacles and can attack and remove most efficiently the growths of any kind whatsoever.
Figure 11 pertains to a knife 16 with a loop-shape design.
Figure 12 finally pertains to a cantilever knife 17 with a very peculiar L-shaped
section.
Figure 13 finally shows how a series knives may be obtained by winding spiral-like
a strip 18 about the circumferential edge of disk 1.
[0018] The above device described with reference to the accompanying figures, may naturally
be adapted and changed in many ways without departing from the scope of the invention
as defined by the appended claims.
[0019] It is particularly to be noted that due to the structure thereof and thus the position
where the teeth come to lie during the scraper operation, said teeth are self-sharpening.
Due to the shape and section thereof, the knives and the disk they are secured on,
may in many cases be cast as a single part. This is notably true when such components
are made from a synthetic material. Many embodiments allow making the disk with the
teeth by injection-moulding or casting.
1. Scraper for removing calcareous growths, anemones, mussels, sea-weeds, algae, etc.
on flat or arched surfaces, which is formed by a motor-driven disk (1) with a number
radial knives (2) distributed along the circumference thereof, which knives have a
structure allowing bending or deflecting thereof along at least two planes, namely
that lengthwise symmetry plane the knife extends in and a plane which lies at right
angle to said first plane and in parallel relationship with the geometrical axis of
the disk (1).
2. Scraper as defined in claim 1, in which said knives (2) are cantilever ones.
3. Scraper as defined in claim 2, in which said knives (2) have a thickness which
progressively decreases towards the free end thereof.
4. Scraper as defined in any one of claims 1 to 3, in which said knives (2) taper
outwards.
5. Scraper as defined in any one of claims 1 to 4, in which said knives (2) are curved
in a curl shape.
6. Scraper as defined in claim 5, in which said curl extends over 360° at the most.
7. Scraper as defined in claim 5, in which said curl extends over more than 360°.
8. Scraper as defined in claim 5, in which said curl is substantially of U-shape.
9. Scraper as defined in claim 5, in which said curl is substantially of S-shape.
10. Scraper as defined in claim 5, in which said curl is substantially of C-shape.
11. Scraper as defined in claim 5, in which said curl is substantially of V-shape.
12. Scraper as defined in claim 1, in which said knives (2) are secured with both
ends thereof on the disk (1).
13. Scraper as defined in claim 12, in which said knives (2) have in one location
at least, a minimum width to make possible bending or deflecting thereof.
14. Scraper as defined in either one of claims 12 and 13, in which said knives (2)
have in one location at least, a minimum thickness to make possible bending or deflecting
thereof.
15. Scraper as defined in any one of claims 1 to 4, in which said knives (2) are comprised
of a resilient curved blade.
16. Scraper as defined in any one of claims 1 to 4, in which said knives (2) are comprised
of a resilient folded blade.
17. Scraper as defined in any one of claims 1 to 16, in which said knives (2) have
at least in that location where they will engage the surfaces to be treated, in a
cross-section, an arc-like section with a convex side facing outwards.
18. Scraper as defined in any one of claims 1, 5, 7, 13 and 17, in which said knives
(2) result from the spiral-like twisting of a continuous strip.
19. Scraper as defined in any one of claims 1 to 18, in which said scouring disk (1)
and knives (2) are made as a single part by a casting or pressing operation.