[0001] The invention relates to a device for cleaning a grate.
[0002] More particularly, the invention is intended for cleaning a grate of the type which
is installed transversely in the current of a creek, a river, a channel or such in
order to retain waste which is carried along by the current, for example, in order
to be able to remove it more easily for discharge and further treatment, or also in
order to protect a downstream-situated pump installation against pollution and the
like.
[0003] It is known that up to the present, for removing waste which has stacked up against
such grate, use is made of machines which are equipped with a gripper, with which
each time a certain amount of waste can be lifted from the water in order to be deposited
in a container.
[0004] A disadvantage of such technique is that the gripper which is in the water, can not
always be seen by the operator of the machine and that consequently the result of
the operation is somewhat insufficient, in particular at the lower end of the grate,
where often quite a lot of waste will remain after cleaning. Nor is it possible to
remove with such gripper the dirt which has stacked up between the bars of the grate.
[0005] Another disadvantage is that such machines having a gripper are rather complex and
expensive and that mostly, an operator is required to perform the work, as a result
of which a grate cleaning action is not only little effective, but moreover also rather
expensive.
[0006] Another known technique for removing the waste is that an endless chain or belt is
used which is provided at its exterior with several hingeably provided shovels, whereby
this belt is installed parallel to the grate, with a portion protruding into the water
and another portion extending up to above a container or conveyor belt installed behind
the grate, in such a manner that the shovels scrape along the grate and carry the
waste along upward, where it drops into the container or onto the conveyor belt.
[0007] With this known technique, too, the result is not optimum and, moreover, the device
applied is very damage-sensitive, as a result of which it is little operationally
reliable and also requires a lot of maintenance, as a consequence of which the utilization
costs can become high.
[0008] Moreover, another disadvantage of this known technique is that cleaning never is
performed up to the bottom side of the grate.
[0009] The present invention aims at offering a remedy for the aforementioned and other
disadvantages.
[0010] To this aim, the invention consists of a device for cleaning a grate of the type
formed by upwardly directed, parallel, whether or not detachable bars which are provided
at regular mutual interspaces, whereby such grate is installed transversely in the
current of a waterway or such, in order to retain dirt, whereby the device consists
of a cleaning machine which is equipped with a lifting basket with an open wall portion
and whereby the cleaning machine is configured such that the lifting basket can be
moved at least over the entire height of the grate along this grate, as a result of
which the dirt is caught between the grate and the lifting basket.
[0011] Preferably, the lifting basket will be provided with teeth which can be brought between
said bars, such that waste which has accumulated between the bars, also is removed
and the grate consequently is cleaned in an efficient manner.
[0012] In a preferred form of embodiment, the cleaning machine will be movably provided
on rails extending parallel to the grate, as a result of which the cost price of the
cleaning machine can be reduced, in consideration of the fact that in that case, no
control device is necessary, and whereby one and the same machine can clean grates
over an unlimited length.
[0013] When, moreover, the wheels of the cleaning machine are seated in a guide provided
on the rails, the cleaning machine always can work under safe conditions, without
any risk of derailing.
[0014] In the most preferred form of embodiment, the cleaning machine will be completely
automatized and, to this end, will be equipped with hydraulic drive means for the
movements, whereby these driving means are connected to separate control valves, which,
whether or not directly, are controlled by means of a common computer.
[0015] This offers the advantage that the cleaning can be performed in a completely automatic
manner, without the intermediary of an operator, and that the cleaning machine can
be programmed such that the lifting basket, during cleaning, serves the entire surface
of the grate, even on the non-visible locations up to the lower edge of the grate.
[0016] Another advantage thereof is that the cleaning machine can be made less expensive,
considering that neither a driver's cabin nor operating elements for an operator must
be provided.
[0017] Such cleaning machine can be radio-controlled from a distance.
[0018] With the intention of better showing the characteristics of the invention, hereafter,
as an example without any limitative character, a preferred form of embodiment of
a device according to the invention for cleaning a grate is described, with reference
to the accompanying drawings, wherein:
figure 1 schematically and in perspective represents a device according to the invention;
figure 2 represents a view according to arrow F2 in figure 1;
figure 3 represents a view similar to that of figure 2, however, for another position;
figure 4 represents a top view of figure 2;
figure 5 represents a view according to arrow F5 in figure 1;
figure 6 represents a view as in figure 5, however, for another position;
figure 7 represents a simplified hydraulic scheme of the control of a device according
to the invention.
[0019] In the figures, an inclined upward-standing grate 1 is represented, which is placed
transverse to the current S in a U-shaped portion, which in this application is formed
of concrete, of a channel 2 or such, whereby said grate 1 extends over the entire
width of the channel 2 in order to retain the dirt carried along by the current S.
[0020] It is clear that such grate 1, to the same end and with the same result, can be provided
in any other waterway, whether of natural origin or not.
[0021] The grate 1 is formed of parallel, upwardly directed bars 3 situated at regular mutual
interspaces and rests with its lower edge on the bottom of the channel 2, whereas
with the upper edge, which normally protrudes above the water level, it is anchored
in points 4 in a construction formed by pillars 5, upon which a horizontal plate 6
is resting.
[0022] On the aforementioned plate 6, a device according to the invention is provided which,
in first instance, consists of a cleaning machine 7, the construction of which is
almost analogous to that of a classical hydraulic digger, such as it is used in civil
engineering; however, which, according to the invention, is adapted in order to work
fully automatic and to move on rails 8, parallel to the longitudinal direction of
the grate 1.
[0023] The rails 8 are provided downstream from the grate 1 on the location 6 by means of
supports 9 and are situated on a level which is situated above the upper edge of the
grate 1.
[0024] The cleaning machine 7 is equipped with a lifting basket 10, with which the dirt
which has accumulated against the grate 1, can be scooped out of the water, and which
subsequently can be deposited in a waste container 11 situated adjacent to the device
on the embankment.
[0025] The lifting basket 10 is provided with teeth 12, the interspaces of which are chosen
such that those teeth can be brought between said bars 3 of the grate 1.
[0026] Preferably, the teeth 12 will be situated at equal mutual interspaces, and such that
the core distance between two adjacent teeth 12 is equal to the core distance between
two adjacent bars 3.
[0027] The dimensions and the interspaces of the teeth 12 may vary in function of the shape
of the bars 3 and the interspaces between these bars 3.
[0028] The device can be provided with several exchangeable lifting baskets 10 which may
mutually vary in respect to dimensions, content and type of teeth 12.
[0029] The lifting basket 10 has an open wall portion 13 which is formed by parallel bars
14 which are situated at a certain distance from each other, such that the water easily
can flow out of the lifting basket 10 and, consequently, only the dirt is scooped
up.
[0030] In this case, the cleaning machine 7 comprises a carriage 15 which, at opposite sides,
is provided with freely rotatable wheels 16 which are guided in a U-shaped portion
17 of the rails 8.
[0031] With a singlefold grate, such carriage (15), of course, will not be necessary.
[0032] The carriage 15 is provided with drive means in the form of an hydraulic motor 20
which is attached at the bottom of the carriage 15 and which is provided with a gearwheel
21 which engages into a toothed rack 22 which is provided under one of said rails
8 over its entire length.
[0033] On the carriage 15 of the cleaning machine 7, a base 23 is rotatably provided which
is provided with drive means in the form of a hydraulic motor 24 and a gearwheel transmission
coupled thereto and not represented in the figures, between this hydraulic motor 24
and the carriage 15.
[0034] On the base 23, an arm 25 is provided pivotably around a horizontal axis 26. Between
the base 23 and the arm 25, drive means are provided in the form of a jack 27 which,
at each extremity, is hingeably connected to the base 23, on one hand, and the arm
25, on the other hand, by means of an axis 28, 29, respectively.
[0035] At the other extremity of the arm 25, a second arm 30 is hingeably provided around
a horizontal axis 31 which is bearing-mounted between the extremities of this arm
30. The arm 30 is provided with drive means in the form of a jack 32, which is provided
between the top side of the arm 25 and one extremity of the arm 30, whereby this jack
32, at each extremity, is hingeable on an axis 33, 34, respectively.
[0036] At the other extremity of the arm 30, said lifting basket 10 is hingeably provided
around an axis 35.
[0037] The lifting basket 10 is controlled by drive means in the form of a jack 36, which,
with one extremity, is hingeably attached to an axis 37 at the top side of the arm
30 and which, with its other extremity, by means of an axis 38, is hingeably connected
to a lever mechanism consisting of two pairs of rods, 39 and 40, respectively, whereby
each of these aforementioned rods is provided with one extremity on the aforementioned
axis 38.
[0038] With their other extremity, the rods 39 are provided on a common axis 41 provided
through the arm 30, whereas the rods 40, with their other extremity, are hingeably
connected to the wall portion 13 of the lifting basket 10, by means of an axis 42.
[0039] It is clear that, by controlling the aforementioned drive means, more particularly,
the hydraulic motors 20 and 24, which respectively provide for the movement of the
cleaning machine 7 along the rails 8, and for swinging the base 23 around a vertical
axis, and the jacks 27, 32 and 36 which operate the arm 25, the arm 30 and the lifting
basket 10, respectively, the lifting basket 10 can be put into a variety of positions.
[0040] The drive means, 20, 24, 27, 32 and 36, respectively, are taken up into a hydraulic
circuit, as, for example, represented in figure 7 in a very schematic manner.
[0041] This circuit comprises a hydraulic power source 43 in the form of a 43A driving a
pump 43B which is fed with liquid from a reservoir 44, whereby the outlet of the pump
43B is connected to a manifold block 45 with several independent control valves 46,
which each are hydraulically connected to one of said drive means 20, 24, 27, 32 and
36.
[0042] Each control valve 46 is provided with a coil 47 which, under the impulse of an electric
current, can move an internal bar, which is not represented in the figures, in order
to let hydraulic oil pass towards the respective hydraulic component, in such a manner
that the delivered flow rate is parallel to the supplied electric control signal.
[0043] The coils 47 are electrically coupled, directly or indirectly, by means of relays
or such, to a computer 48, in which a certain program is loaded for performing synchronized
movements of the driven parts of the cleaning machine 7, to wit the carriage 15; the
base 23; the arm 25; the arm 30, and the lifting basket 10, respectively, in order
to obtain an automatized working of the device.
[0044] Preferably, for the control of the cleaning machine 7, a servo control will be used,
whereby the computer 48, at any moment, takes into account the actual position and
location of the lifting basket 10 in respect to the grate 1, by calculating this position
starting from the position signals which it receives from measuring sensors 49, which,
for clarity's sake, only are represented in figure 7, and which transmit the absolute
or mutual position of said driven parts 15, 23, 25, 30 and 10 and/or of the drive
means 20, 24, 27, 32 and 36 which operate these parts.
[0045] If necessary, an operator control panel 50, represented in dashed line, can be connected
to the computer 48 in order to allow the loading of another performance program or
to adapt the existing performance program, when, for example, the lifting basket 10
is replaced by a lifting basket 10 of, for example, larger or smaller dimensions and
content.
[0046] Once the computer 48 is set and adjusted, the device works completely autonomous.
[0047] The computer 48 is programmed such, that the hydraulic drive means, 20, 24, 27, 32
and 36, respectively, are controlled in a synchronized manner, such that the cleaning
machine 7 automatically positions itself successively at several pre-determined locations
along the grate and that, at each of these locations, the lifting basket 10 is moved
such that it moves with its teeth 12 between the bars 3 of the grate 1 upward, starting
from the lowermost edge of the grate 1, as represented in figure 5, up to the uppermost
edge of this grate 1, as represented in figure 6, such that waste which has stacked
up against the grate 1 or between the bars 3 of the grate 1, is taken up by the lifting
basket 10 and lifted in order to empty the content of the lifting basket 10 in a waste
container 11.
[0048] Afterwards, the cleaning machine 7 moves to a subsequent position along the grate
1 in order to there again lift the waste, according to the same procedure, out of
the water and to deposit it into the waste container 11. The successive positions
of the cleaning machine 7 are chosen such that the successively cleaned zones of the
grate 1 overlap each other.
[0049] The succession of automatic operations can continue until the waste container 11
is full, after which the device, whether or not automatically, is shut down until
the full waste container 11 is replaced by an empty waste container 11.
[0050] The working of the device can be continuous or can also be controlled by the computer
48 in such a manner that the device only is operating during limited, preprogrammed
periods of time.
[0051] It is clear that other forms of control by the computer are possible, for example,
by the intermediary of a separate hydraulic control circuit, operated by electrovalves
or similar.
[0052] According to a not-represented embodiment variant, the whole cleaning process also
can be performed manually by an operator which controls the afore-discussed operations
manually from a driver's cabin which is provided with operating elements for manually
controlling each of said hydraulic drive means, 20, 24, 27, 32 and 36, respectively.
[0053] The present invention is in no way limited to the form of embodiment described as
an example and represented in the figures; on the contrary, a device according to
the invention may be realized in various forms and dimensions, without leaving the
scope of the invention.
1. Device for cleaning a grate (1) of the type formed by upwardly directed, parallel
bars (3) provided at regular mutual interspaces, whereby such grate (1) is installed
transversely in the current of a waterway or such, in order to retain pollutions,
characterized in that the device consists of a cleaning machine (7) which is equipped with a lifting basket
(10) with an open wall portion (13), whereby the cleaning machine (7) is configured
such that the lifting basket (10) can be moved at least over the entire height of
the grate (1) along this grate (1).
2. Device according to claim 1, characterized in that the cleaning machine (7) consists of a base (23) rotatably provided around a vertical
axis; a first arm (25) hingeably provided on the base (23) by means of a horizontal
axis (26); a second arm (30), which, by means of a horizontal axis (31), is hingeably
provided on the first arm (25), whereby said lifting basket (10) is hingeably provided
on this second arm by means of a horizontal axis (35); drive means (20-21-22) for
moving the carriage (15) on the rails (8); drive means (24) for pivoting the base
(23); drive means, (27) and (32), respectively, for pivoting the arms (25) and (30);
and finally drive means (36-39-40) for tilting the collecting basket (10).
3. Device according to claim 2, characterized in that the base (23) is provided on a carriage (15), the wheels (16) of which are guided
in rails (8).
4. Device according to claim 2, characterized in that the rails (8) are parallel to the longitudinal direction of the grate (1).
5. Device according to claim 3, characterized in that the rails (8) are situated upstream from the grate (1) and on a level situated above
the top edge of the grate (1).
6. Device according to claim 2, characterized in that said drive means consist of a motor (20) which is mounted on the carriage (15) and
which is provided with a gearwheel (21) cooperating with a fixed toothed rack (22);
a motor (24) which is provided on the base (23) and a gearwheel transmission between
this motor (24) and the carriage (15); a jack (27) which is provided between the base
(23) and the first arm (25); a jack (32) connecting the first arm (25) to the second
arm (30); and finally a jack (36) which is provided on the second arm (30) and which,
by means of a lever mechanism (39-40), is connected to the lifting basket (10).
7. Device according to claim 5, characterized in that said lever mechanism (39-40) consists of rods, (39) and (40), respectively, which
each are hingeably connected to said jack (36), whereby the rods (39) are hingeably
provided on the second arm (30) and the rods (40), by means of an axis (42), are hingeably
connected to the lifting basket (10).
8. Device according to any of the preceding claims, characterized in that the open wall portion (13) of the lifting basket (10) is formed by parallel bars
(14).
9. Device according to any of the preceding claims, characterized in that the lifting basket (10) is provided with teeth (12) which can be brought between
the bars (3) of the grate (1).
10. Device according to claim 8, characterized in that the teeth (12) are situated at equal mutual interspaces and that the core distance
between two adjacent teeth (12) is equal to the core distance between two adjacent
bars (3) of the grate (1).
11. Device according to any of the preceding claims, characterized in that the cleaning machine (7) is completely automatized.
12. Device according to claim 10, characterized in that said drive means (20-24-27-32-36) are connected to separate control valves (46) which,
whether directly or not, are controlled by means of a common computer (48).
13. Device according to claim 11, characterized in that the computer control is a servo control.
14. Device according to claim 12, characterized in that the computer is coupled to measuring sensors (49) measuring the position of the drive
means (20-24-27-32-36) and/or of the driven parts (10-15-23-25-30).