WO1998055699A1

WO1998055699A1 - Screen cleansing apparatus

Info

Publication number: WO1998055699A1
Application number: PCT/SE1998/000979
Authority: WO
Inventors: Leif Zetterlund
Original assignee: Leif Zetterlund
Priority date: 1997-06-03
Filing date: 1998-05-26
Publication date: 1998-12-10
Also published as: AU8043798A; SE511044C2; SE9702096D0; SE9702096L

Abstract

The present invention relates to a grating cleaning device (1), which comprises a grating (2) and a motor-driven cleaning instrument (3), which cooperates with the grating by means of a rake-like cleaning instrument. According to the invention the portions of the cleaning instrument and the grating, which can mesh with each other, have a multi-fonctional design and purpose, i.e. to, in an introduction period, when they are mutually jointed together, carry out an alignment into the fully joined and consequently final work position, and by means of the alignment design, already in said introduction period carry out a coarse cleaning and achieve an increase in the capacity of the grating to retain contaminants with reduced risk of obstructing the flow, which passes through the grating and, in the final work position, also to accomplish a fine cleaning.

Description

SCREEN CLEANSING APPARATUS

The present invention relates to a grating cleaning device of the type described in more detail in the preamble of claim 1.

Such devices are used e.g. in purifying plants, pumping stations and water inlets for drinking and process water.

The object of such devices is to bring about a coarse separation of large solid contaminants from a water stream, for what purpose there are known gratings , through which the water flow is forced to pass. Of course , said gratings will be stopped-up after some time and it will be necessary to remove from the gratings contaminants, which have adhered to them. For this purpose either strictly manual equipments are used or a cleaning with machinery is performed by means of movable grating portions or motor- driven rakes or the like.

When the conventional grating cleaning with machinery is used , various problems arise. First of all the gratings, due to their construction tend to be easily stopped-up and to obstruct or actually to a considereable degree prevent a normal water flow. Also, the tools designed to carry out the cleaning are considered being impaired by various deficiences . It is e.g. on the whole difficult to achieve a satisfactory cleaning in a relatively short time. Also, there are substantial problems with an exact alignment of the cleaning equipment in e.g. deep and narrow passages. It is particularly difficult to clean so called fine gratings with gap widths of e.g. 2-8 mm. Thus, the gratings will be insufficiently cleaned and consequently their capacity will decrease ; and the cleaning must be carried out more often and possibly be supplemented with manual cleaning. Also, damages to the gratings and their environment and to the mechanical cleaning equipment may arise due to the difficulties in achieving an exact alignment into the correct functional position. The gratings with movable parts have a tendency to get locked, fix contaminants and in their turn be fixed by contaminants. Movable gratings cannot easily take care of sedimentations in the form av sand and gravel in front of a grating. The functioning is always questioned due to all those reasons. The functioning and possible repair jobs are also expensive; in addition , the life of such a grating usually is very limited.

E.g. US-A-2 128 345 relates to a materials handling device with cam-like parts, which mesh with each other. The cam teeth are generally long and fine and have small holes , which can be easily stopped up, the entire device being ineffective. Means which secure the alignment of the cams into each other are missing. The subject matter of US-A-2 009 005 and US-A-1 912 020 have similar problems and drawbacks.

The object of the present invention is to counteract and as much as possible eliminate the above-mentioned problems and deficiences . Also, another object of the invention is to generally develop the state of the art in this field. These objects are attained according to the present invention by mainly designing a grating cleaning device of the type described in the introduction in such a way, as is set forth in the characterizing clause of claim 1.

Additional characterizing features and advantages of the invention are described in the following description, reference being made to the enclosed drawings, which show a preferred but not limiting embodiment of the grating cleaning device according to the drawing, in which , in more detail and partially in schematical form:

Fig. 1 is a cross section of a grating cleaning device according to the invention along section line I-I in Fig. 2;

Fig. 2 is a lateral view of the device according to Fig. 1 and corresponding parts;

Fig. 3 is a view from the left in Fig. 2 of the motor-driven cleaning tool;

Fig. 4 is a section view of a grating according to the invention along section line IV-IV in

Fig. 1;

Fig. 5 is a view from the left in Fig. 1 ; and

Fig. 6-9 are cross sections of alternative grating embodiments

In the drawings a grating cleaning device 1 is shown in its entirety . This device comprises as main portions a grating 2 and a motor-driven cleaning instrument 3.

.The device primarily is designed for gratings in relatively deep and narrow shafts or ducts 4, in which grating 2 can be disposed, e.g. resting on a bottom 5 and filling the space between lateral walls 6, grating 2 suitably being inclined according to Fig. 2.

A grating 2 according to the invention comprises a frame 7 having or comprising lateral profiles all around, between which grating rods 8 and 9 extend, parallelly to each other and preferably made of a flat iron material, which in the device suitably are diposed in vertical planes, which are parallel to a water stream passing through the grating.

The grating rods form with one of their longitudinal edges in relation to the direction of flow at least two planes 10 and 11, at a distance from each other , in the direction of flow, e.g. because flat iron rods 8 and 9 have different widths in the direction of flow and are arranged altematingly (see Fig. 1) . The flat iron rods may instead have the same width in the direction of flow but end within different planes on the downstream side (Fig. 7). According to a further alternative groups of three or more can be used depending on how the widths of flat iron rods 8 , 9 and 9' vary in the direction of flow (Fig. 6b).

The grating has at its bottom a side 12, which is inclined in relation to the direction of flow, and on its sides alignment sides 13 diverging against the direction of flow, the bases 14 of which suitably are parallel to each other and extend somewhat longer towards the flow than the widest rods (or the rods which protrude the longest in the cross section of the grating towards the flow). The divergence of sides 13 corresponds at the free longitudinal edges to between one and two divisions between said widest or most protruding rods, whereas the extension of sides 13 in the direction of flow is 1-5 times longer than the extension of the grating in the same direction. The distance between rods positioned adjacent each other is 2-60 mm, in practical , often used embodiments 10-20 mm.

Cleaning instrument 3 has a shaft 16, which by means of an electric motor 15 can be swung towards and away from grating 2. A support 17 for electric motor 15 can be mounted on a carriage 19, which is provided with runners 18 and which in its turn can be moved along treads 20,21, which e.g. are fastened to a floor support 22, which can be lowered onto the edge area around said shaft 4 or the like . The motor suitably drives said two runners and a swinging device 23 for shaft 16, the latter jointly with a cleaning tool 24, mounted on the free, i.e. the lower end of the shaft, being able to be swung towards and away from the grating, their slopings in relation to the grating being changed. In Fig. 2 the down-driven position of the cleaning tool is shown, the shaft being swung away from the grating. When the lower starting position has been reached, the shaft will be swung counter-clockwise , until the cleaning tool with its free edge, turning away from the shaft, hits the grating. The final stage of this phase is shown in Fig. 1. In this figure it is shown, that cleaning tool 24, designed roughly as a transverse shovel, comprises a base plate 25, fastened to the shaft, from which a blade portion 26 extends downwardly at an angle of about 120 , to which in its turn a rake portion 27 is attached, which extends with an angle of about 90 in relation to shaft 16. It is shown in Fig. 1, that the free long edge of rake portion 27 is designed with relatively wide trapezoidal teeth 28, the base 29 of which has a width, which is as large as the distance between two adjacent grating rods 9 in the outer plane 10, and the top 30 of which is smaller than said distance . The top is provided with a rectangular indent 31, which is relatively flattened and the width of which is somewhat larger than the thickness of grating rods 8. As an altemtive to trapezoidal teeth 28 rectangular teeth can also be used.

Returning now to the above-mentioned final phase it is obvious, that cleaning tool 24 in a simple and automatic way will be centered first of all by means of said alignment sides 13 but subsequently also by means of their bases 14, holes 32 between teeth 28 being positioned exactly in front of rods 9 and the indents subsequently ending up in front of rods 8, which results in that a scraping movement can take place in a double sense in two different planes in the depth direction of the grating. In case stones, twigs and/or other contaminants would prevent cleaning tool 24 from fully penetrating into the grating in the way described above but allow a penetration into e.g. the position shown in Fig. 1, then a purposeful scraping and cleaning movement nevertheless can be done, such coarse obstacles being removed in a first turn, after which finer contaminants can be removed in a second turn, provided the cleaning tool during the upward movement of the scraping cannot penetrate the grating deeper. Scraped off contaminants will then end up on portions 25-27 and be transported upwards, since the motor draws the entire cleaning tool upwards to a position above the ground level, where an emptying will take place.

The design of the grating per se is also very advantageous, since the different planes facing the flow obstructs or prevents a stop up of the grating, since possible obstacles are forced to occupy slanting positions in relation to the grating, a certain continued flow being secured in spite of possible large amounts of accumulated contaminants. Of course, thanks to the shown and described design also a removal of coarse as well as fine contaminants are secured and of course an always guaranteed correct alignment position. Also, the alignment sides bring about an advantageous transverse flow from the sides, which tends to prevent a uniform stop up with contaminants.

The present invention is not limited to the embodiments described above and shown in the enclosed drawings but can be modified and supplemented in an arbitratry fashion according to the scope of the inventive idea and the following claims.

Claims

CLAIMS :

1. A grating cleaning device (1) comprising a grating (2) and a motor-driven cleaning instrument (3) , which cooperates with the grating by means of a rake- like cleaning tool (24) . c h a r a c t e r i z e d in that the portions of the cleaning instrument and the grating , which will mesh with each other , when joined , have a multi-functional design and purpose, namely to, in an introduction period, when said portions are mutually joined, achieve an alignment into the fully joined and consequently final work position and , due to the alignment design, already in said introduction period achieve a coarse cleaning and an increase in the capacity of the grating and retain contaminants with a reduced risk for obstructing the flow, which passes through the grating and to, in the final work position, also achieve a fine cleaning.

2. A grating cleaning device (1) according to claim 1, c h a r a c t e r i z e d in that said grating (2) in a way known per se comprises a frame (7) with or comprising side profiles all around , between which grating rods (8,9) extend, parallel to each other and preferably made of a flat bar iron material, which are mounted within vertical planes, which are parallel to a water flow, which will pass through the grating, and in that the grating rods (8,9) with one of their longitudinal edges form, in relation to the direction of said flow, at least two planes (10,11) at a distance from each other in the direction of flow, e.g. because the flat iron rods (8,9) have different widths in the direction of flow and are arranged altematingly according to Fig. 1 and/or because the flat iron bars have the same width in the direction of flow but end within different planes on the downstream side and/or because there are three or more groups of flat iron rods (8,9,9), which vary as to their width in the direction of flow.

3. A grating cleaning device (1) according to claim 2, c h a r a c t e r i z e d in that the grating (2) comprises at its bottom a side (12), which slopes in relation to the direction of flow and alignment sides (13), which diverge from said sloping sides towards the direction of flow and the bases (14) of which suitably are parallel to each other and protrude somewhat longer towards the flow than the widest rods or the rods, which protrude the most towards the flow in the cross section of the grating .

4. A grating cleaning device (1 ) according to claim 1, c h a r a c t e r i z e d in that the divergence of the alignment sides (13) at the free longitudinal edges corresponds to between one and two spreadings between said widest rods or the rods, which protrude the most, whereas the extent of the alignment sides (13) in the direction of flow is 1-5 times the extent of the grating in the same direction.

5. A grating cleaning device (1) according to any of claims 1-4 , c h a r a c t e r i z e d in that said cleaning instrument (3) comprises a shaft (16), which can be swung by means of an electric motor (15) towards and away from the grating (2) , a support (17) for the electric motor (15) being mounted on a carrriage (19), e.g. provided with runners (18) , which carriage in its rum can be moved along treads (20,21) ,which e.g. are attached to a floor or ground support (22), which can be lowered onto the edge area around a shaft or the like (4), in which the grating (2) is disposed.

6. A grating cleaning device (1) according to claim 5, characterized in that the electric motor (15) suitably is designed to drive said runners (18) as well as a swinging device (23) for the shaft (16) , the latter jointly with said cleaning tool (42), to which the free , i.e. lower end of the shaft is fastened, being swingable towards and away from the grating, their slopings in relation to the grating being changed.

7. A grating cleaning device (1) according to claim 5, characterized in that said cleaning tool (24), designed roughly as a transverse shovel, comprises a base plate (25), fastened to said shaft and from which a blade portion (26) extends downwards, to which in its turn a rake portion (27) is connected, the angle between the rake portion (27) and the shaft (16) being about 90.

8. A grating cleaning device (1) according to any of claims 1-7, characterized in that the active portion (27) of the cleaning tool (24) comprises a free longitudinal edge having rectangular or trapezoidal teeth (28), the base (29) of which has a width , which roughly is equal to the distance berween two adjacent grating rods (9) in said outer plane (10), and the top (30) of which is smaller than said distance, and in that the top at its center comprises a relatively flattened rectangular indent (31), the width of which is somewhat larger than the thickness of those grading rods (8), which end in the inner plane (11) in order to receive the longitudinal edge portion of the latter, which portion is exposed to said indent.

9. A grating cleaning device (1) according to any of claims 1-7, characterized in that the cleaning tool (24) can be automaticly centered, first of all by means of said alignment sides (13) and subsequently by means of their bases (14), the holes (32) between the teeth (28) being positioned exactly in front of the rods (9) and the indents (31) ending up exactly in front of the rods (8), which implies, that a double scraping movement can take place , in a double sense, in two different planes in the depth direction of the grating (2).

AMENDED CLAIMS

[received by the International Bureau on 29 October 1998 (29.10.98); original claims 1-9 replaced by amended claims 1-10 (3 pages)]

1. (Amended) A grating cleaning device (1) comprising a grating (2) and a motor-driven cleaning instrument (3), which cooperates with the grating by means of a rake-like cleaning tool (24), said grating (2) comprising a frame (7) with or comprising surrounding side sections, between which grating rods (8, 9, 9') extend, parallel to each other and preferably made of a flat iron bars, which are located within vertical planes , which are parallel to a water flow, which is to pass through the grating, said cleaning instrument (3) comprising a shaft (16), which can be swung by means of an electric motor (15) towards and away from the grating (2), a support (17) for the electric motor (15) being mounted on a carrriage (19), which e.g. is provided with runners (18), and which in its turn can be moved along treads (20, 21), which e.g. are attached to a floor or ground support (22), which can be lowered onto the edge area around a shaft or the like (4), in which the grating ( 2 ) is disposed c h a r a c t e r i z e d i n t h a the portions of the cleaning instrument and the grating, which are to mesh with each other, when joined, have a multi-functional design and purpose, namely to, in an initial stage, when said portions are mutually joined, achieve an alignment into the fully joined and consequently final work position by the grating (2) comprising at its bottom a side (12), which slopes in relation towards the direction of flow and alignment sides (13) diverging towards the direction of flow, and in that the grating rods (8, 9) with one of their longitudinal edges form, in relation to the direction of said flow, at least two planes (10, 11) at a distance from each other in the direction of flow, the alignment design already in said initial stage being provided to achieve a coarse cleaning and an increase in the capacity of the grating to retain contaminants with a reduced risk for obstructing the flow, which passes through the grating and to, in the final work position, also achieve a fine cleaning.

2 . (Amended) A grating cleaning device ( 1 ) according to claim 1 , c h a r a c t e r i z e d i n t h a t said flat iron rods ( 8 , 9 , 9 ' ) have different widths in the direction of flow and are arranged altematingly .

3. (Amended) A grating cleaning device (1) according to claim 1, c h a r a c t e r i z e d i n t h a t the flat iron bars (8, 9) have the same width in the direction of flow but end within different planes on the downstream side.

4. (Amended) A grating cleaning device (1) according to claim 1, c h a r a c t e r i z e d i n t h a t there are three or more groups of flat iron rods (8, 9, 9'), which vary as to their position in the direction of flow.

5. (Amended) A grating cleaning device (1) according to claim 1, c h a r a c t e r i z e d i n t h a t the bases (14) of the alignment sides are parallel to each other and/ or protrude somewhat longer towards the flow than the widest rods or the rods, which protrude the most towards the flow in the cross- section of the grating.

6. A grating cleaning device (1) according to claim 1, c h a r a c t e r i z e d i n t h a t the divergence of the alignment sides (13) at the free longitudinal edges corresponds to between one and two spreadings between said widest rods or the rods, which protrude the most, whereas the extent of the alignment sides (13) in the direction of flow is 1-5 times the extent of the grating in the same direction.

7. (Amended) A grating cleaning device (1) according to claim 1, c h a r a c t e r i z e d i n t h a t the electric motor (15) is designed to drive said runners (18) as well as a swinging device (23) for the shaft (16), the latter jointly with said clea- ning tool (24), to which the free, i.e. lower end of the shaft is fastened, being swingable towards and away from the grating, their slopings in relation to the grating being changed.

8. A grating cleaning device (1) according to claim 1, c h a r a c t e r i z e d i n t h a t said cleaning tool (24) , designed roughly as a transverse shovel, comprises a base plate (25), fastened to said shaft and from which a blade portion (26) extends downwards, to which in its turn a rake portion (27) is connected, the angle between the rake portion (27) and the shaft (16) being about 90°.

9. (Amended) A grating cleaning device (1) according to any of claims 1-8, c h a r a c t e r i z e d i n t h a t the active portion (27) of the cleaning tool (24) comprises a free longitudinal edge having rectangular or trapezoidal teeth (28), the base (29) of which has a width, which roughly is equal to the distance between two adjacent grating rods (9) in said outer plane (10), and the top (30) of which is smaller than said distance, and in that the top at its center comprises a relatively flat rectangular indent (31), the width of which is somewhat larger than the thickness of those grating rods (8), which end in the inner plane (11) in order to receive the longitudinal edge portion of the latter, which portion is exposed to said indent.

10. (Amended) A grating cleaning device (1) according to any of claims 1-8, c h a r a c t e r i z ed i n t ha t the cleaning tool (24) is provided to be centered automatically, firstly by means of said alignment sides (13) and subsequently by means of their bases (14), the holes (32) between the teeth (28) being positioned exactly in front of the rods (9) in the external plane (10) and the indents (31) ending up exactly in front of the rods (8) in the internal plane (11), for bringing about a double scra- ping movement in two different planes in the depth direction of the grating (2 ) .