WO2014162070A1

WO2014162070A1 - Screening box

Info

Publication number: WO2014162070A1
Application number: PCT/FR2014/000072
Authority: WO
Inventors: Roland Lamarche
Original assignee: Chauvin
Priority date: 2013-04-02
Filing date: 2014-04-02
Publication date: 2014-10-09
Also published as: FR3003776A1; FR3003776B1

Abstract

A screening box (1) comprising at least one inlet opening (2) configured to allow the introduction of a product for screening, and at least two outlet openings (3) configured to allow the product for screening to be discharged. At least one elastic element (6) is mechanically coupled to the box (1) and is configured to have a first state and a different second state. A force generator (8, 9) is configured to shift the elastic element (6) into the first state or into the second state. At least one screen (4) locking member (7) is mounted movable in translation in the box (1) by means of the elastic element (6). The locking member (7) is configured to llock a screen (4) in the usage position between the inlet opening (2) and one of the outlet openings (3) when the elastic element (6) is in the first state and to leave the screen (4) movable when the elastic element (6) is in the second state.

Description

Chest to sift

Technical field of the invention

The invention relates to a sieving machine, and more specifically to a sieving chest.

State of the art

Screening machines are typically used in fields such as the construction industry (use in quarries), the food industry, chemistry, pharmacy or any other activity using powders to separate powdery materials into plastics. according to their size.

In the field of construction, the sieves may for example be intended to remove pebbles present in gravel or soil. In the chemical and pharmaceutical industry, it is possible, for example, to use sieving machines to separate powders into larger or smaller grains. The higher the number of sieves, the greater the possibility of cuts in the material. The disadvantage of this type of machine is that the larger pieces pass over the first sieve, which can quickly cause a significant loss of efficiency. It is therefore essential that the sieves are easily accessible by the user to be able for example to be cleaned, or to repair a defective sieve. In general, it is found that the maintenance of the chests to be sieved is long. An exemplary embodiment is described in WO 2008/111985. The sieving chest here comprises several stages of sieves, and each sieve is secured to the sieving chest. If, for example, a screen is torn, the sieves must be separated one after the other until the defective sieve is found.

Object of the invention

An object of the invention is to provide a screening box inside which is one or more easily accessible sieves.

Conventionally, the box comprises at least one inlet configured to allow the introduction of a product to be sieved, and at least two outlet ports, configured to allow the exit of the product to be sieved.

According to one aspect of the invention, at least one elastic element is mechanically coupled to the trunk and is configured to have a first state and a second different state. The elastic element is associated with a force generator configured to pass the elastic element in the first state or in the second state according to the needs of the user. The trunk also comprises at least one sieve lock member movable in translation in the trunk by means of the elastic element, and configured to lock a sieve in the position of use between the inlet orifice and one of the exit ports when the elastic member is in the first state, and to leave the sieve movable when the elastic member is in the second state. According to one embodiment, the locking member comprises at least two shims separated by the elastic element and configured to block the screen between the two shims. Advantageously the wedge is a frame. This may have an outer wall connected to the inner wall of the trunk. This avoids the passage of material between the shim and the inner wall of the trunk, and thus ensures a good efficiency of the machine. According to one embodiment of the invention, the first state of the elastic element is a state of compression, and the second state corresponds to a state of rest.

In this embodiment, the force generator comprises at least one locking piece configured to lock the elastic member in the compression position in response to a control member. The locking piece may for example comprise a cam eccentric.

In an alternative embodiment, the first state of the elastic member may be a state of rest, and the second state may be a state of stretch. In this case, the force generator may comprise at least one locking piece configured to lock the elastic member in the stretching position in response to a control member. Moreover, whatever the embodiment, the locking member may be configured to block a plurality of sieves arranged successively between the inlet orifice and one of the outlet orifices.

The invention also relates to the method of dismounting the trunk to access the sieve. This involves the following steps: Actuate the force generator to unlock the sieves by passing the elastic element of the first state to the second state,

• remove a trunk wall configured to be removable,

• translate the sieves to the outside of the box.

Brief description of the drawings

Other advantages and features will emerge more clearly from the following description of particular embodiments of the invention given by way of non-limiting example and represented in the accompanying drawings, in which:

- Figure 1 schematically illustrates a sectional view of a box according to one embodiment, when the screen supports are locked in the position of use, that is to say when the elastic elements are in a state constrained,

- Figure 2 corresponds to a sectional view of the trunk according to the same embodiment, when the elastic elements are in a state of rest,

FIGS. 3 and 4 show a box to be sieved according to a second embodiment,

FIGS. 5 and 6 illustrate a box to be sieved according to a third embodiment.

detailed description

In Figure 1, there is shown schematically a sectional view of a chest 1 according to a first embodiment. By way of illustration and not limitation, the chest 1 has an inlet 2 of the material, and four outlet ports 3a, 3b, 3c and 3d for collecting pieces of materials of different sizes.

In this embodiment, the box comprises three sieves 4a, 4b, 4c defining three sieving zones each connected to one of the outlet orifices 3a, 3b, and 3c. The outlet port 3d is located under the sieve 4c.

Each sieve 4 defines a sieving stage. The sieve 4a has holes larger than those of the sieve 4b, and the sieve 4b has holes larger than those of the sieve 4c. In this way, the pieces of material exiting through the orifice 3a are larger than those leaving through the orifice 3b, the pieces coming out through the orifice 3b are larger than those leaving through the orifice 3c, and the pieces coming out through port 3c are larger than those coming out through port 3d.

When the box has a plurality of sieves 4, the screens 4 are arranged so that the characteristic size of their holes is smaller and smaller in the direction of flow of the material, that is to say between the input 2 and output 3d.

Each screen 4a, 4b, 4c comprises a support 5a, 5b, 5c which may advantageously be in the form of a frame.

In the embodiment shown in FIGS. 1 and 2, the sieves 4 may advantageously be based on locking members 7, for example wedges. The locking members may be configured to make a point or extended contact with the screens 4. Each locking member may for example ensure contact with a sieve 4 over the width or length. In an advantageous embodiment, provision may be made for locking members 7 to be interposed between each sieve 4, so that the upper locking member 7 of a sieve 4 is also the lower locking member 7 of the sieve 4. immediately above. This embodiment is particularly advantageous because the number of parts is reduced, which limits the risk of failure of the box to be sieved 1.

In the particular embodiment shown in Figures 1 and 2, the screen support 5a 4a is interposed between the wedges 7a and 7b, the support 5b between the wedges 7b and 7c, and the support 5c between the wedges 7c and 7d. In the embodiment shown in Figures 1 to 4, a shim 7 mechanically connects two successive sieves 4. Here, the wedges 7 advantageously define a closed frame whose outer walls may for example be in contact with the walls of the box. In this way, the material introduced into the orifice 2 necessarily passes through the sieves 4a, 4b, and 4c, and not between the supports 5a, 5b, 5c and the inner wall of the trunk 1. The various stages of the trunk 1 are therefore sealed against each other, which ensures the proper calibration of the pieces of material.

At least one of the shims 7 is movably mounted in translation. At least part of the shims 7 is mechanically connected to the walls of the trunk with the aid of elastic elements 6. In the embodiment illustrated in FIG. 1, all the shims 7 are mechanically connected to one another by means of Elastic elements 6. In a first embodiment, the elastic elements 6 may for example be helical springs. In the embodiment illustrated in Figures 1 and 2, a set of elastic elements 6a connects the wedges 7a and 7b, a set of elastic elements 6b connects the shims 7b and 7c, a set of elastic elements 6c connects the shims 7c and 7d. Finally, the set of elastic elements 6d connects the wedge 7d to the bottom wall of the screening box 1. It may for example be advantageous to associate a set of four elastic elements 6 to each sieve 4. It is also possible to arrange a larger number of elastic elements 6, for example if the sieves 4 have large dimensions. The screen 4 may be mounted to move in translation in the same direction as the locking member.

In the preferred case where the elastic elements 6 are springs, it may be advantageous to associate with a sieve 4 springs of identical stiffness. This makes it possible to ensure the translation of the screens 4 and shims 7 along an axis orthogonal to the sieves 4, which is in the figures a vertical axis. The stiffness of the springs 6 and the positions of the outlet orifices 3 may be judiciously chosen so that each outlet orifice 3 is placed facing a screen 4, so as to effectively remove the pieces of material. A role of the elastic elements 6 is to perform a modulation of the distance between two shims 7 to define a locking position and another position. In the other position, the user can install or remove a sieve 4. In the embodiment illustrated in Figures 1 and 2, the elastic elements 6 are springs, it may be advantageous that their block length is smaller than the thickness of the screen supports 4, the block length being the length of a spring which is compressed to the maximum, i.e. the minimum length of the spring. In this way, the screen 4a can be immobilized between the wedges 7a and 7b, the screen 4b can be locked between the wedges 7b and 7c, and the screen 4c can be immobilized between the wedges 7c and 7d. Conversely, when the screening box 1 is not used and the screens 4 are not locked in the position of use, the springs 6 can have a second state close to a state of rest, but they can also be forced.

To pass the elastic elements from the first state to the second state, and vice versa, the screening chamber 1 is advantageously provided with a force generator comprising here a control member 8 of a locking piece 9.

The control member 8 may for example be a rocker lever. This control member 8 is configured to pass the elastic elements 6 in two different states including at least one forced state for example, or in a constrained state or in a state of rest, depending on whether the box to be screened 1 is used or not . The elastic elements 6 are therefore passive elements, that is to say they pass from a constrained state to a state of rest only in response to an external stimulus.

When the screening box 1 is used, the elastic elements 6 are placed in the compression position by actuation of the control member 8. In FIGS. 1 and 3, the locking piece 9 applies a stress on the locking members 7 .

In the embodiment shown in the figures, the locking piece 9 corresponds to a telescopic piston whose first end 9a is integral with the upper wall of the box 1. When the control member sets the piston 9 in motion, the second end 9b of the piston is placed against the locking member 7a and pushes it along a vertical axis. The movement of the locking member 7a has the effect of compressing the elastic elements 6a and transmitting the force applied to the other locking members 7b, 7c and 7d. In one embodiment, it is possible, for example, to provide that the control member 8 simultaneously controls four locking pieces 9 placed at the four corners of the upper wall of the box 1. In this way the force exerted on the locking member 7a allows the latter to translate vertically. In general, the number of locking pieces 9 which must be fixed on the upper wall of the box 1 is a function of the force that must be exerted to push the locking member 7a in order to block the sieves 4 in the position of use.

Alternatively to the telescopic piston, the locking piece 9 could also be a rack meshing with a gear wheel actuated by the control member 8. One could also consider a cam / cam follower or cam eccentric, or cylinder to replace the piston.

By way of example, when the control member 8 is in a horizontal position, the elastic elements 6 are sufficiently compressed so that there is no longer any possible translation of the supports 5. The fact of placing the elastic elements 6 in a constrained state makes it possible to block the sieve supports 4 in the position of use. The screening box 1 can then be used.

The material is introduced into the inlet port 2 while the trunk 1 is set in motion by an external device. The trunk 1 can for example vibrate or turn on itself, which has the effect of lowering the material gradually through the sieves 4.

When sieving, pieces of finer material than mesh of sieve 4a pass through it while pieces larger than the meshes of the sieve 4a remain on the surface and are progressively eliminated by the outlet orifice 3a under the effect of the vibrations of the trunk 1.

Similarly, the pieces of material larger than the mesh of the sieve 4b remain on the surface, while the rest of the material falls on the sieve 4c. Under the effect of the movements of the trunk 1, the pieces of material present on the surface of the sieve 4b are discharged through the outlet orifice 3b. Likewise, the pieces larger than the mesh of the sieve 4c are eliminated through the outlet orifice 3c, while the pieces passing through the sieve 4c are finally discharged through the outlet orifice 3d.

The material is therefore separated into pieces of different sizes whose characteristic dimensions correspond to those of sieves 4.

During the use of the sieving chest 1, pieces of material can get stuck in the sieves of the screens 4. This has the effect of gradually reducing the performance of the trunk 1. The user must therefore perform regular maintenance to maintain the efficiency of the machine. It must therefore have easy access to sieves 4.

Advantageously, the screening box 1 is arranged so as to secure and separate several sieves 4 at the same time, that is to say that several sieve supports 4 are blocked or unlocked at the same time. When the screen supports 4 are unlocked, the elastic elements 6 are advantageously in a state of rest, that is to say not constrained, which limits the risk of injury to the user. To access the screens 4, the user can advantageously manipulate the control member 8. In the first embodiment shown in FIG. As an illustration, it is necessary to move the lever 8 from a horizontal position to a vertical position. This has the effect of moving the springs 6 to the rest position. It is then necessary to remove a wall of the trunk 1 advantageously configured to be removable or provided with hinges to be tilted. The wall of the trunk 1 which can be moved is preferably one of the side walls, so that the user can simultaneously access the different sieves 4.

At this stage, the user can directly slide the sieves 4 along the wedges 7, similarly to a drawer that is opened. The displacement of the sieves is orthogonal to the direction of translation of the elastic elements 6.

The cleaning is greatly simplified compared to the devices of the prior art. Simply brush the screens 4, or wash them with water to remove dust and chips stuck in the mesh.

Another advantage is that the user has simultaneous access to all the sieves 4 in a single mechanical operation, which makes it possible to limit the duration of the maintenance, and therefore to increase the efficiency of the sieving machine.

This embodiment of the screening box 1 is very versatile. For example, it is possible to limit the number of sieves 4 by leaving sieving zones without sieves 4, since the forces originating from the force generator are directly transmitted from one sieving zone to another by the elastic elements 6 on the sieves 4. the locking members 7.

In a second embodiment illustrated in FIGS. 3 and 4, the force generator comprises a locking member 10 configured to locking the elastic members 6 in the stretching position, in response to a control member 8 such as a lever.

More specifically, the locking member 10 preferably comprises a cable 10a at the end of which is a hook 10b attached to a ring 10c. The force generator may also comprise a winding element such as a pulley (not shown), the cable 10a being able to be wound around this element. When the sieves 4 are locked in the position of use, the elastic elements 6 are in a first state constrained in stretching or close to the state of rest. Conversely, when the sieves 4 are movable in the screening box 1, the elastic elements 6 are in a second state corresponding to a state of stretching.

In the particular case where the elastic elements 6 are springs, it can be provided that their free length is slightly less than the height of the sieves 4, the free length being the length of the spring when it is not compressed or stretched. In this way, the springs 6 hold the screens 4 in the locked position between the locking members 7, unless the user actuates the force generator.

To access the sieves 4, the user advantageously actuates the control member 8. Initially, when the sieves 4 are locked in the use position, the cable 10a is not in tension (see Figure 3). On the other hand, when the locking member 10 is actuated by the control member 8, the cable 10a is progressively tensioned and may preferentially be wound around the winding element. In this way, the hook 10b starts to pull on the ring 10c and the elastic elements 6 are gradually stretched. Finally, the locking member 10 makes it possible to sufficiently stretch the elastic elements 6 to allow the extraction of the sieves 4 from the box to be screened 1.

Alternatively, the locking piece 10 could for example be a tension spring (not shown) directly connected to the control member 8, and attached to a ring such as the ring 10c. It is therefore possible to make a screening box 1 which is configured to block sieves 4 with elastic members 6 acting in tension or compression.

These embodiments make it possible to use the screening box 1 with sieving zones without sieves 4. The forces are directly transmitted from one sieving zone to another by the elastic elements 6.

In a third embodiment shown in FIGS. 5 and 6, the screening box 1 can be provided with elastic elements 6 resting on locking members 7 'which are fixed. The sieves 4 rest on the elastic elements 6. In order to limit possible failures of the box to be sieved 1, it is expected that the locking elements 7 have dimensions of the same order of magnitude as those of the elastic elements 6 , which makes it possible to limit the size and the number of pieces present in the box to be sieved 1.

In this embodiment, the sieves 4 have a specific structure. They are provided with movable locking members 7, for example in the form of support rods which mechanically connect two sieves 4. In this way, the force generated on a sieve 4 is generated on another sieve 4 by means of the locking member 7. The sieves 4 are movable or locked in the use position according to whether the user places the force generator in one position or another. Here, the force generator is similar to that of the first embodiment. It is for example provided with a control member 8 such as a lever, and a locking piece 9 such as a telescopic piston or a cam eccentric. It is also possible to provide a plurality of locking members 9 controlled by the control member 8. The force generator can act in compression or in tension. When the sieves 4 are locked in the use position, the locking member 9 bears against the support 5a of the sieve 4a. It pushes the latter downwards, and the force is transmitted to the supports 5b and 5c via the support rods.

Therefore, in this embodiment, the role of the elastic elements 6 is not to transfer the compression forces of a support 5 to the other, but to act as a damper between the locking members 7 ' and the supports 5.

As in the other embodiments of the invention, they can adopt two states. When the sieves 4 are locked in the position of use, the elastic elements 6 are in a first state corresponding to a state of compression, whereas when the sieves 4 are left mobile in the trunk 1, the elastic elements 6 are in a second position. state corresponding to a state close to a state of rest.

Thus, there is provided an effective device, simple to perform, and particularly suitable for use in areas where machines are used continuously.

Claims

claims

Screening box (1) comprising:

¹ at least one inlet (2) configured to allow introduction of a product to be screened,

At least two outlet openings (3) configured to allow the exit of the product to be sieved,

at least two screens (4) placed one above the other so as to define at least three stages of the box to be sieved (1),

At least two frames (5) each supporting a screen (4), the frames (5) being configured to ensure the sealing of the stages of the box to be sifted (1) relative to each other,

At least two sets of elastic elements (6), each set of elastic elements (6) being associated with a sieve (4), mechanically coupled to the trunk (1) and configured to present a first state and a second different state ,

A force generator (8, 9) configured to move the set of elastic elements (6) into the first state or the second state,

At least one sieve locking member (7) mounted to be movable in translation in the trunk (1) between the frames (5) of the sieves (4) by means of the sets of elastic elements (6), and configured for locking a sieve (4) in use position between the inlet port (2) and one of the outlet ports (3) when the sets of elastic elements (6) are in the first state and for leaving the sieve (4) mobile when the sets of elastic elements (6) are in the second state.

2. Screen box (1) according to claim 1, wherein the locking member comprises at least two shims (7) separated by the set of elastic elements (6).

3. Sieve box (1) according to claim 2, wherein the shim (7) is a frame.

4. Sieving chest (1) according to any one of claims 1 to 3, wherein the first state is a state of compression of the set of elastic elements (6) and wherein the second state is a state of rest of the set of elastic elements (6).

5. Chest screen (1) according to claim 4, wherein the force generator (8, 9) comprises at least one locking piece (9) configured to lock the set of elastic elements (6) in the position of compression in response to a control member (8).

6. Screen box (1) according to claim 5, wherein the locking piece (9) comprises a cam eccentric.

7. Screening chest (1) according to any one of claims 1 to 3, wherein the first state is a state of rest of the set of elastic elements (6) and wherein the second state is a state of stretching of the set of elastic elements (6).

8. Screen box (1) according to claim 7, wherein the force generator (8, 9) comprises at least one locking piece (9) configured to lock the set of elastic elements (6) in position d stretching in response to a control member (8).

9. Screening box (1) according to any one of claims 1 to 8, wherein the locking member (7) is configured to block a plurality of screens (4) arranged successively between the inlet port ( 2) and one of the outlet ports (3).

10. A method of dismantling the screening box (1) according to any one of claims 1 to 9 to access the sieves (4), the method comprising the following steps:

Actuating the force generator (8, 9) to unlock the sieves by passing the set of elastic elements (6) from the first state to the second state,

• remove a trunk wall (1) configured to be removable,

• translate the sieves (4) to the outside of the trunk (1).