FR3057468A1 - CURTAIN WITH CONVERGENT SLOPES - Google Patents

Abstract

A hopper screen (10) having a frame (12) defining a sieving surface, and at least a first sieving opening (24, 24 ', 24 ") formed in the sieving surface for allowing the flow of a product through the screen in a direction of flow (E) The invention is characterized in that the first screening opening is bordered by first and second flow slopes (26, 26 ', 26 ", 28, 28', 28") spaced from each other and converging towards each other in the direction of flow.

Description

FIELD OF THE INVENTION [1] The present invention relates to the field of screens configured to equip, for example and without limitation, a hopper. It relates in particular to a screen mounted on a hopper fitted to a machine for transporting fluid screed and / or concrete.

STATE OF THE PRIOR ART [2] In a known manner, a hopper defines a receiving volume making it possible to receive, contain and transport a product, the hopper having an introduction opening opening into the receiving volume; the hopper is also configured to ensure a flow of said product towards a discharge line, the discharge line comprising means for moving the product in a transport sheath, such as a transmission shaft with turns or a pump with progressive cavities, so as to move the product to its place of spreading.

[3] Furthermore, also in known manner, a screen comprises a frame, allowing the screen to be mounted for example on a hopper so as to cover the introduction opening, the frame defining a sieving surface. The screen makes it possible both to constitute a safety device making it possible to protect the operator from the elements placed under the screen, for example means for moving the delivery line arranged downstream of the hopper, while forming a screening device. configured to retain the unsuitable aggregates by their calibration with the displacement means and / or with the desired final characteristics of the screed or of the concrete formed from said product. Furthermore, the screen must also allow the product to flow into the hopper, so as to allow its subsequent movement to its place of spreading.

[4] In known manner, the screening surface of the screen may include a metal sheet in which openings are formed, or a metal fabric formed by the intertwining of metal son.

[5] The product poured into the hopper is an assembly of materials of generally mineral nature which brings together aggregates and a binder; in particular to ensure the mechanical strength necessary for its use, the product can also be combined with fibers of various types and shapes which modify the flow properties. However, due to the presence of flat surfaces formed by the metal sheet or due to the intertwining of the son of metallic fabric, the screens known from the prior art tend to oppose the flow of such products in the hopper, and consequently, compromise the progression of the products to their place of spreading and the homogeneity and therefore the characteristics of the product transported.

PRESENTATION OF THE INVENTION [6] The aim of the present invention is therefore to propose a screen facilitating the flow of products, in particular the flow of products of heterogeneous structure, without compromising the safety and sieving functions of the screen and without alter the formulation of the products transported.

[7] According to the invention, this object is achieved thanks to a screen for hopper comprising a frame defining a screening surface, and at least a first screening opening formed in the screening surface to allow the flow of a produced through the screen in a flow direction, the first screen opening being bordered by first and second flow slopes spaced from each other and converging towards each other in the direction of flow.

[8] The first and second flow slopes thus function like a funnel, and make it possible to promote the flow of the product along said slopes to the lower end of said slopes, towards the receiving hopper, when the screen is mounted so as to cover the opening for introducing a hopper.

[9] The invention is set out below in a series of variant embodiments, which can be considered alone or in combination with one or more of the preceding.

[10] In certain embodiments, the frame has first and second opposite sides having a first length, the first screening opening extending over all or part of the first length, preferably over more than half of the first length.

[11] By this arrangement, a significant amount of the product can flow through the first screening opening.

[12] In some embodiments, the frame has a first side having a longitudinal edge, and a first wing mounted on the longitudinal edge, said first wing forming the first slope of the first screening opening.

[13] The arrangement on the first side of a first wing forming the first slope of the screening opening makes it possible to facilitate the production of the screen according to the present invention.

[14] In certain embodiments, the screen further comprises at least one second screening opening bordered by first and second flow slopes spaced from one another and converging towards each other according to the flow direction, the screen comprising a first angle forming both the second slope of the first screening opening and the first slope of the second screening opening.

[15] The presence of at least two openings allows the flow of a larger quantity of product. Furthermore, the use of a first angle iron to form both one of the slopes of the first and second flow openings facilitates the production of the screen according to the present invention.

[16] Preferably, the first angle has first and second wings respectively forming the second slope of the first screening opening and the first slope of the second screening opening, and an edge connecting the first and second wings.

[17] In other words, the first angle has an inverted V-shaped profile, considered in the direction of flow, so that its upper part formed by the edge connecting the first and second wings does not have flat surface which would oppose the flow of the product, unlike the screens known from the prior art and mentioned above.

[18] The upper term relating to the first angle is understood according to the direction of flow of the product through the screen surface of the screen according to the present invention.

[19] In some embodiments, considered in the direction of flow, the first and second wings form an angle between 10 ° and 170 °, preferably between 60 ° and 120 °, preferably of the order of 90 °.

[20] The spacing of the first and second wings of the first angle can thus be adapted according to the product having to pass through the screen, and more particularly according to its components and their dimensions and characteristics, and makes it possible to adjust the flow speed of said product towards the receiving hopper.

[21] In certain embodiments, the screen further comprises first removable fixing means configured to mount the first angle piece removably on the frame.

[22] By this arrangement, the dimensions of the screening openings can be changed, so as to adapt the screen to the product it is intended to receive. In particular, the adjustment of the dimensions of the screening openings makes it possible to adapt the screening function to the dimensions of the product aggregates.

[23] In some embodiments, the screen further comprises a second angle having a first wing forming the second slope of the second screening opening, the first and second angles extending substantially parallel to each other. other.

[24] The presence of a plurality of angles allows the formation of a plurality of sieving openings in the screen, so as to further facilitate the flow of the product; in addition, the distance separating the various angles can be adapted to allow the screening of aggregates of particular dimensions.

[25] In some embodiments, the screen includes vibration means configured to cooperate with the screen frame so as to apply vibration to the screen.

[26] The application of vibrations to the screen through its frame contributes to the efficiency of the product flow through the sieving surface.

[27] The invention also relates to a reception hopper defining a reception volume and an introduction opening opening into the reception volume, the reception hopper comprising a screen according to the present invention, the screen extending over the opening.

BRIEF DESCRIPTION OF THE DRAWINGS [28] The invention and its advantages will be better understood on reading the detailed description given below of an embodiment of the invention given by way of non-limiting example. This description refers to the pages of attached figures, on which:

- Figure 1 shows a fluid screed transport machine and / or concrete comprising a receiving hopper equipped with a screen according to the present invention;

- Figure 2 shows a perspective view of an example of a screen according to the present invention;

- Figure 3 shows a top view of an example of a screen according to the present invention; and

- Figures 4 and 5 schematically show sectional views along planes transverse to each other of an example of a screen according to the present invention.

DETAILED DESCRIPTION OF EXAMPLES OF EMBODIMENT [29] FIG. 1 represents a transport machine 100, for example for transporting a fluid screed and / or for transporting concrete. Usually, the machine 100 comprises a frame 102 supporting a power supply; the chassis 102 may also include an axle and wheels (not shown) so as to allow the machine 100 to be moved. In addition, the machine 100 may include a drawbar (not shown) in order to allow the machine 100 to be towed by a vehicle. Alternatively, the machine 100 can be directly mounted on the platform of a vehicle.

[30] In addition, the machine 100 comprises a reception hopper 106 defining a reception volume and having an introduction opening opening into the reception volume to introduce a product into the reception volume of the reception hopper 106; the receiving hopper 106 is configured to allow the flow of said product, for example a fluid screed or concrete, to a discharge line 108, the discharge line comprising means for moving the product in a transport sheath, such as '' a transmission shaft with turns or a progressive cavity pump, so as to move the product to its place of spreading.

[31] For example and in a nonlimiting manner, the product is an assembly of aggregates, comprising inert materials which may be of mineral nature, of a binder, such as for example cement, bitumen or clay, and fibers, which can be of various types and forms, such as for example synthetic or metallic fibers.

[32] Thus, the receiving hopper 106 forms a container configured to constitute a reserve of the product to be transported while allowing the flow of said product to its place of spreading by the delivery line 108.

[33] Furthermore, the machine 100 comprises a screen 10 mounted on the receiving hopper 106, and more particularly mounted so that it extends over the opening for introducing the receiving hopper 106, or above said introduction opening.

[34] As shown in Figures 2 to 5, the screen 10 according to the present invention comprises a frame 12, for example and in a nonlimiting manner of substantially parallelepiped shape; the frame 12 thus has first, second, third and fourth sides 14, 16, 18, 20 opposite in pairs, which delimit a sieving surface.

[35] The screen 10 further comprises a plurality of angles 22, 22 ', 22 which extend, for example and without limitation, substantially parallel to each other in a longitudinal direction L between the third and fourth sides 18, 20 of the frame 12; thus, the angles 22, 22 ′, 22 extend substantially parallel to the first and second sides 14,16.

[36] It is therefore understood that the screen 10 comprises a grid constituted by the frame 12 and the plurality of angles 22, 22 ', 22, said grid forming a plurality of flow slots, or sieving openings, which will be described more in detail in the following description, the flow slots being configured to allow the flow of a product, such as a fluid screed or a concrete, through the screen 10.

[37] The angles 22, 22 ', 22 are mounted spaced from each other, and also at a distance from the first and second sides 14, 16, so that the screen surface of the screen 10 has a plurality of openings screen 24, 24 ', 24 which are configured to allow the flow, through the screen 10 in a flow direction E, of the product intended to be stored and transported by the hopper 106 of the machine 100.

[38] For example and without limitation, the screen openings 24, 24 ', 24 extend over a significant part of the length L of the first and second sides 14, 16 of the frame 12, preferably over more than the half of said length, preferably over 80% of said length.

[39] As shown in particular in Figure 5 which shows a sectional view of the screen 10 in a substantially vertical plane and perpendicular to the longitudinal direction L, each of the screening openings 24, 24 ', 24 is bordered by first 26, 26 ', 26 and second 28, 28', 28 flow slopes which are spaced from one another and which converge towards each other in the flow direction E.

[40] The first and second sides 14, 16 of the frame 12 each have a longitudinal edge 30, 32 from which extend first and second wings 34, 36 respectively. For example and without limitation, the first and second wings 34, 36 are fixed respectively to the first and second sides 14, 16 by a bolting system; one could obviously conceive any other type of fixing.

[41] The first and second wings 34, 36 each form a downward slope towards the center of the sieving surface; in other words, the distal end of the wings 34, 36, which is the end of the wings opposite the proximal end by which the wings are fixed respectively to the longitudinal edges 30, 32 of the first and second sides 14, 16 , is arranged lower than said proximal end, considered in the direction of flow E.

[42] Furthermore, as shown in particular in Figure 5, the angles 22, 22 ', 22 of the screen 10 each have first 38, 38', 38 and second 40, 40 ', 40 wings connected to one to the other by an edge 42, 42 ', 42 which can alternatively be rounded or sharp.

[43] The wings of the angles 22, 22 ', 22 each form descending slopes from the edge 42, 42', 42; in other words, the distal end of the wings, which is the end of the wings opposite the proximal end by which the wings are connected to each other by the edge of the angle, is arranged more below that said proximal end, considered in the direction of flow E. Said still otherwise, the angles 22, 22 ', 22, when they are mounted in the frame 12 of the screen 10, have an inverted V-shaped profile.

[44] Considered in the direction of flow E, the first and second wings of each of the angles 22, 22 ', 22 form between them an angle a of between 10 ° and 170 °, preferably between 60 ° and 120 ° , preferably of the order of 90 °.

[45] The first wing 34 extending from the first side 14 thus forms, with the nearest angle 22, a screening opening 24 bordered, on the one hand, by said first wing 34, and, on the other hand, by the first wing 38 of the angle 22, the distal ends of the first wing 34 on the first side 14 and of the first wing 38 of the adjacent angle 22 extending at a distance from each other, for example and from in a nonlimiting manner parallel to one another in the longitudinal direction L. The screening opening 24 thus has, considered in the direction of flow E, a V shape, the bottom of the V being open to allow the flow of the product in the receiving hopper 106. The two slopes of the screening opening 24 formed respectively by the first wing 34 of the first side 12 and by the first wing 38 of the angle 22 thus converge one towards the other according to the flow direction E.

[46] Similarly, the second wing 36 which extends from the second side 16 of the frame 12 also forms with the nearest angle 22 a screen opening having two flow slopes spaced apart from one other and which converge towards each other in the direction of flow E.

[47] As shown in particular in FIG. 4 which represents a sectional view of the screen 10 in a substantially vertical plane and parallel to the longitudinal direction L of the angles 22, 22 ′,

22, said angles 22, 22 ', 22 are mounted on first and second 44, 46 mounting means; more particularly, the first longitudinal ends 23, 23 ', 23 of each of the angles 22, 22', 22 are fixed, for example by welding or by any other fixing means, to the first mounting means 44, while the second ends longitudinal 25, 25 ′, 25 of the angles are fixed, by welding or by any other fixing means, to the second mounting means 46.

[48] The first and second mounting means 44, 46 are then attached and fixed, by fixing means 45 such as for example by a bolting system, to the third and fourth sides 18, 20 of the frame 12 of the screen 10.

[49] The fixing means 45 are configured to allow a removable mounting of the grid, otherwise called filtration lattice, constituted by the angles 22, 22 ', 22 and by the first and second mounting means 44, 46, on the frame 12 of the screen 10. It would thus also be possible to design a kit comprising a frame 12 and a plurality of grids, the angles of said grids having dimensions and spacings different from one grid to another, to allow the user to have different grids adapted to their needs, and more particularly adapted to the characteristics of the product to be sold.

[50] As shown in particular in Figure 5, the angles are arranged relative to each other so as to form, between two successive angles, a screening opening. More particularly, the screening openings 24 ', 24 thus formed between two successive angles have two flow slopes which are formed respectively by the second wing 36 of a first angle 22 and by the first wing 38' of a second angle 22 'adjacent to the first angle 22.

[51] The mounting of the angles 22, 22 ', 22 in the frame 12 of the screen 10 and the presence of the wings 34, 36 extending from the first and second sides 14, 16 of the frame 12 allow the formation of openings screen 24, 24 ', 24 having convergent slopes, in the direction of flow E of the product poured over the screen 10, the shape of said screen openings promoting the flow of said product through the screen surface of the screen

10. In other words, the presence of the screening openings having a V shape, the bottom of the V being open, contributes to the funnel function of the screen 10.

[52] The edge of the angles 22, 22 ', 22 does not form a flat surface which could slow down or even oppose the flow of the product through the sieving surface.

[53] Furthermore, the arrangement of the angles in the frame 12 allows the screen 10 to ensure the protection of the user, by protecting him from the elements arranged in the bottom of the receiving hopper 106, and to ensure the screening function, the aggregates, the dimensions of which are greater than the space separating two successive angles or the space separating the end angles of the wings extending from the first and second sides, being blocked by the screen 10 ; such aggregates would risk damaging the elements ensuring the transport of the product downstream of the receiving hopper 106. The screen 10 according to the present invention is therefore configured so that such aggregates do not pass through the screening surface.

[54] In order to further improve the flow of the product through the screen 10, said screen 10 further comprises vibration means 60, comprising for example and without limitation an electric or pneumatic vibrator, which are configured to cooperate with the frame 12 so as to apply vibrations to the screen 10. In addition, the effects of the actuation of the vibration means 60 on the flow of the product are particularly significant because of the large surfaces formed by the wings of the various elements of the screen 10. In particular, the surface formed by the wings of the various elements of the screen according to the present invention is greater than that formed by an interlacing of metal wires.

[55] For example and without limitation, the angles 22, 22 ', 22 and the various elements constituting the frame 12 are formed by mechanical welding; the angles can thus be formed by the assembly of two flat parts connected, for example by welding, one to the other at the edge while being inclined with respect to one another. Alternatively, they can be formed from a flat sheet folded so as to form two distinct slopes.

[56] In the example shown in the different figures, the angles have identical structures and dimensions. It would obviously be possible to conceive, without departing from the scope of the present invention, on the one hand of the angles of which the two wings would have different dimensions and / or shapes, and on the other hand of a screen 12 comprising angles of different dimensions, or even angles which are arranged so that the screening openings have different shapes and dimensions.

[57] Although the present invention has been described with reference to specific exemplary embodiments, it is obvious that modifications and changes can be made to these examples without departing from the general scope of the invention as defined by the claims. In particular, individual features of the various illustrated / mentioned embodiments can be combined in additional embodiments. Therefore, the description and the drawings should be considered in an illustrative rather than restrictive sense. In addition, although the screen according to the present invention has been described with reference to a screed and / or concrete transport machine, one could conceive the mounting of said screen on any other type of device configured to transport a product formed of constituents of different dimensions and / or characteristics.

Claims (10)

1. Screen (10) for hopper (106) comprising a frame (12) delimiting a screening surface, and at least one first screening opening (24, 24 ', 24) formed in the screening surface to allow flow of a product through the screen in a flow direction (E), the screen being characterized in that the first screen opening is bordered by first and second flow slopes (26, 26 ', 26, 28 , 28 ', 28) spaced from each other and converging towards each other in the direction of flow. 2. Screen (10) according to claim 1, characterized in that the frame has first and second opposite sides (14, 16) having a first length, the first screening opening extending over all or part of the first length , preferably over more than half of the first length. 3. Screen (10) according to claim 1 or 2, characterized in that the frame has a first side (14, 16) having a longitudinal edge (30, 32), and a first wing (34, 36) mounted on the longitudinal edge, said first wing forming the first slope of the first screening opening. 4. Screen (10) according to any one of claims 1 to 3, characterized in that it further comprises at least a second screening opening bordered by first and second flow slopes spaced apart from one other and converging towards each other in the direction of flow, the screen comprising a first angle (22, 22 ', 22) forming both the second slope of the first screening opening and the first slope of the second screening opening. 5. Screen (10) according to claim 4, characterized in that the first angle (22, 22 ', 22) has first and second wings (38, 38', 38, 40, 40 ', 40) respectively forming the second slope of the first screening opening and the first slope of the second screening opening, and an edge (42, 42 ', 42) connecting the first and second wings. 6. Screen (10) according to claim 4 or 5, characterized in that, considered in the direction of flow, the first and second wings form an angle between 10 ° and 170 °, preferably between 60 ° and 120 °. 7. Screen (10) according to any one of claims 4 to 6, characterized in that it further comprises first removable fixing means (45) configured to mount the first angle in a removable manner on the frame. 8. Screen (10) according to any one of claims 4 to 7, characterized in that it further comprises a second angle having a first wing forming the second slope of the second screening opening, the first and second angles s 'extending substantially parallel to each other. 9. Screen (10) according to any one of claims 1 to 8, characterized in that it comprises vibration means (60) configured to cooperate with the screen frame so as to apply vibrations to the screen. 10. Receiving hopper (106) defining a receiving volume and an introduction opening opening into the receiving volume, the receiving hopper being characterized in that it comprises a screen (10) according to any one of claims ί to 9, the screen extending over the introduction opening. 3/5