Pneumatic device and object sorting system

Abstract

The invention relates to a pneumatic device (10) comprising modules (100), each module having compressed air supply valves (12), the intensity of the compressed air jet supplied by each module (100) being variable according to the combination of valves (12) activated, and outlet nozzles (14) of one or more air jets coming from the modules (100), according to the number of modules (100) activated, the nozzles having aligned outlet orifices. The invention also relates to an object sorting system comprising the pneumatic device.

Description

[0001] PNEUMATIC DEVICE AND SYSTEM FOR SORTING OBJECTS

[0002] Technical field

[0003] The present invention relates to a pneumatic device and an object sorting system comprising the pneumatic device.

[0004] Prior art

[0005] The increase in production rates of objects, for the pharmaceutical industry for example, requires means to ensure a high level of quality. It also appears that the inspection of an entire population of objects rather than a sample is increasingly desired. For this purpose, there are online object analysis devices that allow precise measurement of each of their physical quantities and compositions. Once the objects have been analyzed, a decision is made whether or not to keep the objects; objects that are not kept are excluded from the production lines. Given the speed of production rates, the problem encountered is that the time to sort between objects is very limited.

[0006] Document US20160016200 describes a pneumatic device for sorting products in the food industry, such as seeds or grains of rice or wheat. The device comprises solenoid valves, each having a series of air jet orifices. The solenoid valves each have an air inlet in a compartment; the air is then distributed into each orifice via a respective valve opened by the electrification of a coil or kept closed by an elastic member. However, since the pneumatic device of this document is intended for sorting seeds, it has a large number of orifices expelling air jets that must all be of the same volume. This makes it bulky and imprecise.

[0007] There is therefore a need for a device that can sort objects quickly and accurately while limiting the space required.

[0008] Statement of the invention

[0009] To this end, the invention proposes a pneumatic device, comprising - modules, each module having compressed air supply valves, the intensity of the compressed air jet supplied by each module being variable depending on the combination of activated valves,

[0010] - outlet nozzles for one or more air jets from the modules, depending on the number of modules activated, the nozzles having aligned outlet orifices.

[0011] Alternatively, the modules are fanned out relative to the nozzles.

[0012] According to one variant, the modules respectively have a conduit directing the compressed air from the valves to the nozzles, the valves being on either side of the conduit relative to the direction of flow of the compressed air in the conduit.

[0013] Alternatively, the valves are connected by an orifice to the conduit, each valve having a different orifice diameter.

[0014] Alternatively, the valves are arranged along the conduit according to the diameter of the orifices, with the valve with the smaller diameter orifice being at the distal end of the conduit relative to the nozzles.

[0015] According to one variant, the device comprises six modules, each module comprising at least four valves, preferably five valves.

[0016] According to one variant, the device further comprises a pressure sensor at the inlet of the modules, capable of measuring the pressure drops caused by successive openings of the valves.

[0017] The invention also relates to an object sorting system, comprising at least one pneumatic device as described previously.

[0018] According to one variant, the system further comprises a channel guiding the objects in a scrolling direction, the nozzles directing one or more air jets in the channel towards the objects to be sorted according to the characteristics of the objects to be sorted.

[0019] According to a variant, the channel has an adjustable width transverse to the direction of scrolling of the objects depending on the characteristics of the objects.

[0020] According to a variant, the system further comprises

[0021] - a chamber for analyzing the characteristics of the objects to be sorted - at least one sorting lane towards which the objects are diverted by actuating one or more air jets according to the characteristics analyzed in the analysis chamber.

[0022] According to one variant, the system further comprises a control unit activating all or part of the modules and valves depending on the characteristics of the objects analyzed in the analysis chamber.

[0023] According to one variant, the control unit activates all or part of the modules and valves depending in addition on the pressure available upstream of the valves.

[0024] The use in this document of the verb "to understand", its variants, and its conjugations, cannot in any way exclude the presence of elements other than those mentioned. The use in this document of the indefinite article "un", "une", or of the definite article "le", "la" or "I'", to introduce an element does not exclude the presence of a plurality of these elements.

[0025] The terms "first", "second", "third", etc. are used in this document exclusively to differentiate between different elements, without implying any order between these elements.

[0026] All of the preferred embodiments and all of the advantages of the pneumatic device are transposed mutatis mutandis to the sorting system.

[0027] Brief description of the figures

[0028] Other characteristics and advantages of the present invention will appear on reading the detailed description which follows, for the understanding of which reference will be made to the appended figures which show:

[0029] - figure 1, a schematic view of a part of a pneumatic device according to an example of the invention;

[0030] - figure 2, a sectional view of the device;

[0031] - figure 3, a rear view of the device of figure 2;

[0032] - figures 4 and 5, perspective views of a sorting system according to an example of the invention;

[0033] - figure 6, a schematic top view of the sorting system; - figure 7, a schematic view of the sorting system.

[0034] The drawings of the figures are not to scale. Like elements are generally denoted by like references in the figures. For the purposes of this document, identical or similar elements may bear the same references. Furthermore, the presence of reference numbers or letters in the drawings cannot be considered as limiting, including when these numbers or letters are indicated in the claims.

[0035] Detailed description of embodiments of the invention

[0036] The invention relates to a pneumatic device, comprising modules, each module having compressed air supply valves. The intensity of the compressed air jet supplied by each module is variable depending on the combination of activated valves. The device further comprises outlet nozzles for one or more air jets from the modules, depending on the number of activated modules, the nozzles having aligned outlet orifices. Such a device combines the adjustment of the number of outlet air jets with the intensity of the air jets. This makes it possible to apply a deflection force to objects that are to be sorted very quickly with a precision adapted to the characteristics of the objects while limiting the size of the device.

[0037] Figure 1 illustrates a schematic view of a part of the pneumatic device 10. The device 10 comprises modules of which only the module 100 is shown. Other modules comprising the same elements are shown in Figures 2 and 3. The module 100 comprises a plurality of valves 12, for example four or five in number as can be seen in Figure 1. The valves are supplied with compressed air from a tank of sufficient volume (minimum 5 liters, maximum 15 liters) and the pressure of which is precisely adjusted by a precision pressure regulator; this ensures the most stable supply possible to the valves 12. In Figure 1, the valves 12 are thus supplied via a supply duct 11. At the input of the supply to the modules 100, a pressure sensor 15 on the supply duct 11 is capable of measuring the pressure drops caused by successive openings of the valves.The pressure sensor 15 makes it possible to correct the opening of the valves 12 according to the pressure present at the inlet. The valves 12 may or may not be identical within a module or from one module to another. When the valves are the same, this makes it easier to control the valves; different valves allow even finer control. The valves 12 may be of different types, such as proportional valves but preferably “on / off” type valves. “On / off” valves are very responsive, which is an advantage in the case of high object scrolling rates. Also, these “on / off” valves are smaller. It is preferable to use a plurality of smaller valves rather than a larger valve capable of allowing a large flow rate at full opening.Indeed, there are more forces to combat to open a large valve (return force of the springs, inertia of the masses of the slides and other moving elements to be set in motion, and friction of the seals) so that the opening or closing times are for example of the order of a few milliseconds. In order to produce air jets in very small "firing windows", the opening time of the valves 12 is less than 3 ms, preferably less than 2 ms, preferably less than 1 ms.

[0038] The module 100 further comprises an outlet nozzle 14 for the air jet coming from the module 100. The intensity of the single jet of compressed air supplied by each module 100 is variable depending on the combination of activated valves 12. The modules 100 can be selectively activated and, within each module 100, the valves 12 can be selectively activated. Each jet is therefore proportional to the characteristics of the objects to be sorted. The nozzle 14 makes it possible to best position the air jet specific to each module relative to the objects to be sorted. The nozzle is a duct machined in a casing 16, the casing 16 then being fixed to the module. The geometry of the outlet orifice of the nozzle is chosen depending on the characteristics of the air jets. A non-circular geometry, oval for example, can be advantageous. All nozzles may be an interchangeable modular element of the device 10 in order to adapt to the conditions of use of the device and the objects to be sorted.The diameter of the nozzle outlet orifice is between 1 mm and 8 mm, preferably between 2 mm and 5 mm, more preferably between 2.5 mm and 4 mm, for example 3 mm, to obtain an air jet per module allowing efficient sorting.

[0039] The module 100 further comprises a conduit 18 directing the compressed air from the valves to the nozzle 14. The arrow 20 indicates the direction of flow of the air in the conduit 18 to the outlet of the nozzle 14. The valves can be placed along the conduit 18 within a module. Preferably, the valves 12 are on either side of the conduit 18 relative to the direction of flow of the compressed air in the conduit 18 within a module; in other words, the valves are in opposition (without necessarily being opposite each other) or on both sides of the conduit 18. Such an assembly of the valves makes it possible to reduce the volumes required in the device (both the space occupied by the valves and the volumes of the conduits). The conduit 18 is thus more compact at the valves 12.

[0040] The conduit 18 may comprise several sections arranged to take into account the size of the valves within the module. Also, these sections make it possible to arrange the valves within a module and the modules relative to each other while ensuring the same pressure drop between the different modules. The length of the conduit 18 is as short as possible to minimize the distance between the outlet orifices of the valves and the outlet orifices of the nozzles.

[0041] The conduit may comprise a first section 181 to which the valves 12 are connected as described above. The conduit 18 may comprise a second section 182 connecting the first section 181 at its end to the nozzle 14. The arrangement of the second conduit 182 within the module is chosen so as to reduce the size of the modules within the device. The second section 182 may be oblique relative to the first section 181, and is preferably straight, which generates less pressure loss. The diameter of the conduit 181 is between 2 and 5 mm, preferably between 2.5 and 4 mm, for example 3 mm, and the diameter of the conduit 182 is between 3 and 6 mm, preferably between 3.5 and 5 mm, for example 4 mm - this ensures an air jet at the outlet of the device allowing efficient sorting of the objects while limiting the size of the conduits.The conduit 18 opens at its end 183 at the outlet of the module 100; the nozzle 14 is positioned at the end 183 of the module 100 and precisely directs the jet of compressed air specific to each module towards the objects to be sorted.

[0042] The valves 12 are connected to the conduit 18, in particular to the first section 181, by outlet orifices 13. Each valve has a different orifice diameter 13. There may be a relationship between these conduits 13, in terms of diameter or area. This makes it possible to vary the intensity of the air jets. Within a module 100, if 'x' is the number of valves 12, 2 Xis the number of possible valve opening combinations, one of which corresponds to all the valves being closed. Within the module 100, the valve 12 with the smaller diameter orifice is at the distal end of the duct 18 relative to the nozzles 14; this prevents the airflow propelled by the valves with a smaller diameter orifice in the duct 18 from being disturbed by the turbulence of an airflow propelled by valves with a larger diameter orifice.

[0043] The outlet orifices of the valves are between 0.4 and 3 mm, preferably between 0.5 and 2.5 mm. This allows rapid release of compressed air in the conduit 18 while limiting the size of the valves.

[0044] Figure 2 illustrates a sectional view of the pneumatic device 10. The device 10 is mounted in a casing 80. The nozzles 14 are shown at the outlet of the device 10, expelling air jets 20, and are connected to the ends 183 of the conduits 18 supplied by the valves 12. The orifices of the nozzles 14 are aligned. The orifices of the nozzles 14 are in the same plane. The orifices of the nozzles have a spacing (between the central axes) of between 3 and 5 mm, preferably between 3.5 and 4.5 mm, more preferably 4 mm, to ensure both compactness of the nozzle and air jets allowing efficient sorting. The outlet orifices of the nozzles 14, each orifice corresponding to a module 100 comprising several valves 12, are such that the arrangement of the jets is flat or, in other words, the air jets form a flat curtain.The range over which the jets act from the orifices and according to the direction of the jets, being from 5 to 50 mm, preferably from 10 to 35 mm, i.e. a range of 25 mm. This allows the compactness of the device, while ensuring sufficient space to provide a number of jets, corresponding to the number of modules, adapting to the characteristics of the objects to be deflected.

[0045] The arrangement of the valves 12 within the modules 100 on either side of the conduit 18, and in particular of the conduit 182, is particularly advantageous for limiting the size of the device 10. In Figure 2, some of the valves 12 are shown in the upper part of the modules 100 and some of the valves 12 in the lower part of the modules 100. As shown in Figures 1 and 2, three valves 12 are in the upper part and two valves are in the lower part of the modules 100.

[0046] The modules 100 may be arranged in a fan shape relative to the nozzles 14. In other words, the modules 100 are arranged in orange wedges relative to the nozzles 14. This is visible at the top of Figure 2 where three valves 12 of each module 100 are aligned radially around the nozzles. This allows for an identical arrangement of the modules 100 relative to each nozzle 14 while ensuring the compactness of the device 10 in the housing 80. This ensures exactly the same airflow channels for each nozzle, particularly in terms of length, geometry and volume. The modules 100 may be of modular construction; one or more modules are used depending on the desired performance of the device 10 and the modules may be grouped. The modules 100 may be constructed in groups of several modules. This makes the device 10 easier to manufacture.Furthermore, the modules 100 are identical from a "pneumatic" point of view in that the valves 12 of the modules are connected in the same way to the nozzle outlets of one module to the other. There is therefore the same response time for the formation of each air jet. Furthermore, the modular construction allows for the manufacture of smaller parts and in greater numbers. The modular construction of the modules 100 can also be in groups of several modules 100, for example three modules 100 grouped together.

[0047] Figure 3 illustrates a rear view of the device of Figure 2 in which the fan-shaped arrangement of the modules 100 is better visible. The valves 12 of each module 100 have an arrangement aligned according to converging rays towards the nozzles (not visible). According to the example of Figure 3, the modules 100 have three valves 12 in their upper part and two valves 12 in their lower part; the five valves 12 of each module 100 are arranged in fan-shaped planes around the nozzles 14. The valves 12 may be arranged on bars 22.

[0048] The invention also relates to an object sorting system which comprises the pneumatic device 10. The objects to be sorted can be nominal objects (nominal sample diverted to the test station) or non-compliant objects (debris, capsules with little or no filling, etc.). Thanks to the combination of the selective activation of the number of modules and the number of valves within each module, the air jets are adapted to the objects so as to sort the objects efficiently. Such a system can be used in the pharmaceutical industry to divert objects such as pharmaceutical tablets or capsules (capsules, empty or filled), from 20 mg to several grams.

[0049] Figures 4 and 5 illustrate perspective views of the sorting system 30. The system comprises a chamber 32 for analyzing the characteristics of the objects to be sorted. The chamber 32 analyzes all the objects, the pneumatic device 10 being able to deflect the objects according to the characteristics analyzed in the analysis chamber 32. A control unit selectively activates all or part of the modules 100 and the valves 12 according to the characteristics of the objects analyzed in the analysis chamber 32. The objects can be accelerated to pass individually into the chamber 32 opposite a microwave sensor which allows the prediction of their mass and / or their humidity level, and which precedes the sorting device. This measuring chamber 32 also allows the quantification of the speed of the objects and their time of arrival at the sorting jets. The objects travel in a line, at high speed - between 5 m / s and 25 m / s. Objects exit chamber 32 through tube 36.The objects travel opposite the device 10 which operates the deviation of the objects according to non-conformity or other criteria, detected in the chamber 32. The orifices of the nozzles 14 are aligned, along an axis transverse to the direction of movement of the objects. This makes it possible to intercept the objects efficiently. The air jets then form a plane, or curtain, transverse to the direction of movement of the objects. A plurality of devices 10 can be used. For example, two (figure 4), three or even four devices 10 can be used, in order to better adapt to the sorting rates imposed by the speed of movement of the objects. One of the devices 10 can be dedicated to the deviation of non-conforming objects and another device 10 dedicated to test sampling (possibly in addition to a systematic analysis in chamber 32).The devices 10 can be arranged around the direction of scrolling of the objects, for example one above the other, on either side of the scrolling of the objects.

[0050] The system may comprise a channel 34 for guiding the objects leaving the chamber 32 in a direction of travel. The channel 34 makes it possible to convey the objects in a row following a quasi-rectilinear trajectory. This makes it possible to present the objects one by one opposite the device 10, which facilitates their deflection. The channel comprises two flat surfaces 341 and 342 guiding the objects.

[0051] The width of the channel 34 is adjustable transversely to the direction of movement of the objects to be sorted. The width of the channel is adjustable in the direction of alignment of the nozzles 14. The space between the flat surfaces 341, 342 is adjusted to the width of the objects to be sorted. The channel 34 is adjustable so as to direct objects whose width varies between 3 mm and 25 mm depending on the format of the product to be sorted. The nozzles 14 direct one or more air jets in the channel 34 towards the objects to be sorted depending on the characteristics of the objects to be sorted.

[0052] Figure 6 shows a schematic top view of the sorting system 30. Figure 6 shows how to adapt the air jets to the objects according to their width, by varying the number of activated modules - besides the fact that the intensity of each jet varies according to the combination of valves activated within each module. At the outlet of the chamber 32, the objects are led into the channel 34, between the flat surfaces 341 and 342. For narrow objects, the flat surfaces are brought as close as possible to each other so that a single nozzle 14 directs the air jet from the device 10 into the channel 34. A single module 100 is then activated. For larger objects, the planar surfaces are spaced apart so that two nozzles 14 direct the air jet from the device 10 into the channel 34. For even larger objects, the planar surfaces are spaced apart again so that three nozzles 14 direct the air jet from the device 10 into the channel 34.According to the example of Figure 6, up to six nozzles 14 can dispense air jets, corresponding to the activation of six modules 100. The width of the channel 34 is for example between 5 and 50 mm, preferably between 5 and 30 mm, preferably between 5 and 25 mm, to adapt well to the number of air jets. The device 10 and the sorting system 30 make it possible to generate a jet of variable width and intensity. Such a variation makes the system 30 versatile, adaptable to objects of variable mass, size, geometry, speed, etc.

[0053] Figure 7 shows a schematic view of the sorting system 30, in particular, with one or more sorting lanes 38, 40. At the outlet of the chamber 32, the objects are guided by the channel 34 then pass opposite the nozzles of one or more devices 10. The objects to be diverted pass through the air jets 20 forming a curtain. The device(s) 10 divert the objects towards one or other of the sorting lanes - according to the arrows 42, 44 - due to an inconclusive sampling test or conformity test. The unsorted objects continue their trajectory according to the arrow 46. According to Figure 7, the diversion is carried out in the vertical plane; a device 10 can be placed above the movement of the objects to divert them towards a lower lane 40 and another device 10 can be placed below the movement of the objects to divert them towards an upper lane 38. Sorting can be in a horizontal plane.

[0054] The distance between the outlet of the chamber 32 and the position of the nozzles 14 is chosen so as to allow time for the object to exit the chamber 32 before being deflected if necessary. Otherwise, the object could already be subjected to a transverse force while it is still partially driven and guided by the tube 36, thus risking hindering the deflection of the object.

[0055] The number of air jets and the intensity of each air jet produced respectively by a module 100 are variable according to an input instruction from the control unit. The instruction determines the number of modules 100 activated and the combination of valves 12 activated within each module 100. The operation of each jet will therefore be proportional to this instruction. This instruction is calculated according to several characteristics analyzed in the chamber 32. The mass of the objects is taken into account, a different combination of valves 12 being activated to increase or decrease the intensity of the jet. The speed of the objects is also taken into account as well as the time at which the object will arrive at the height of the jets. Also, the shape and volume of the objects influence the number and intensity of air jets activated as well as the width of the channel 34.The force to be applied to the object as well as the pressure present upstream of the valves are also taken into account so as not to damage the objects. This makes it possible to maintain the quality of the sorting even if the tanks are not able to recover their nominal pressure as quickly in cases where several openings occur close together in time. The distance between the device 10 and the objects to be sorted is a factor to be taken into account to guarantee the performance of the sorting. The distance between the jet outlet (outlet orifices of the nozzles 14) and the axis of movement of the objects is between 10 and 40 mm, preferably between 15 and 30 mm, for example 20 mm. This makes it possible to present the objects to be diverted to the jet in an area where the diversion will be most effective while preserving the integrity of the objects to be diverted.

[0056] The control unit includes a PLC (for "Programmable Logic Controller"), an input / output board with highly responsive digital outputs (including an FPGA processor - for "field-programmable gate array"), and a power control board (equipped with FPGA controllers and MOSFETs - for "Metal Oxide Semiconductor Field Effect Transistor"). This architecture allows reaction times of a few microseconds, and ensures a sorting process with valve opening or closing times of the order of a few milliseconds.

[0057] The sequence for establishing an air jet is as follows. The PLC commands the opening of valves 12. The digital output that activates valve(s) 12 is energized. The time elapsed since the command depends on the architecture of the control system implemented (PLC programming and cycle times, communications between the PLC and the digital output card, type of digital output card, etc.). This time can be up to 1 millisecond. Then, the current is established in the actuating coil of the respective valves, until it reaches a sufficient force to begin moving the moving parts of the valves (up to a few milliseconds); depending on the combination of valves, the controlled valves open and the air begins to flow. Depending on the geometry of the ducts and the nozzle, the air will take some time before exiting through the nozzle orifices. Finally, the jet is established.First, there are transient phenomena for a short period of time, before reaching a stable jet. The time between the activation signal and the moment when the jets are fully established is less than 5 ms, preferably less than 4 ms, preferably less than 3 ms, preferably less than 2 ms.

[0058] Under the effect of the air jet(s), the objects are diverted from their substantially rectilinear path towards the sorting lane(s) 38, 40. Thanks to the sorting lanes 38, 40, the device 10 and the adaptation of the number and intensity of the air jets, the diverted objects are not damaged. These objects can be subject to a new conformity check in which a device 10 can again be implemented; the objects can be returned to the main circuit because they have not been damaged.

[0059] The present invention has been described in relation to specific embodiments, which are of purely illustrative value and should not be considered as limiting. In general, it will be obvious to a person skilled in the art that the present invention is not limited to the examples illustrated and / or described above.

Claims

Demands 1. Pneumatic device (10), comprising - modules (100), each module having compressed air supply valves (12), the intensity of the compressed air jet supplied by each module (100) being variable depending on the combination of valves (12) activated, - outlet nozzles (14) for one or more jets of air from the modules (100), depending on the number of modules (100) activated, the nozzles (14) having aligned outlet orifices.

2. Device according to claim 1, wherein the modules (100) are fanned out with respect to the nozzles (14).

3. Device according to claim 1 or 2, wherein the modules respectively have a conduit (18) directing the compressed air from the valves (12) to the nozzles (14), the valves (12) being on either side of the conduit with respect to the direction of flow of the compressed air in the conduit.

4. Device according to claim 3, in which the valves (12) are connected by an orifice (13) to the conduit (18), each valve having a different orifice diameter.

5. Device according to claim 4, wherein the valves (12) are arranged along the conduit (18) according to the diameter of the orifices (13), the valve with the orifice of smallest diameter being at the distal end of the conduit (18) relative to the nozzles (14).

6. Device according to any one of claims 1 to 5, comprising six modules (100), each module (100) having at least four valves (12), preferably five valves (12).

7. Device according to any one of claims 1 to 6, further comprising a pressure sensor (15) at the inlet of the modules, capable of measuring the pressure drops caused by successive openings of the valves.

8. Object sorting system (30), comprising at least one pneumatic device (10) according to any one of claims 1 to 7.

9. System (30) according to claim 8, further comprising a channel (34) guiding the objects along a scrolling direction, the nozzles (14) directing one or more jets of air in the channel (34) towards the objects to be sorted according to the characteristics of the objects to be sorted.

10. System (30) according to claim 9, wherein the channel (34) has a width adjustable transversely to the direction of scrolling of the objects according to the characteristics of the objects.

1. System (30) according to any one of claims 8 to 10, further comprising - a chamber (32) for analyzing the characteristics of the objects to be sorted - at least one sorting channel (38, 40) towards which objects are diverted by actuation of one or more air jets according to the characteristics analyzed in the analysis chamber (32).

12. System according to claim 11, further comprising a control unit activating all or part of the modules (100) and valves (12) according to the characteristics of the objects analyzed in the analysis chamber (32).

13. System according to claim 12, wherein the control unit activates all or part of the modules (100) and valves (12) further depending on the pressure available upstream of the valves (12).