PRECIOUS METAL GRAIN DOSING GROUP, DOSING SYSTEM AND METHOD

Description

TITLE: METAL GRIT DOSING GROUP PRECIOUS, DOSING SYSTEM AND METHOD 5 DESCRIPTION Scope of application

[0001] The present invention falls within the sector goldsmith and refinery, particularly in the context of the machines used for the production of ingots 10 of precious metal. Specifically, the invention concerns the dosing systems used in the process of manufacturing precious metal ingots, such as example of gold, silver, platinum, where the precise measurement of precious metal granules is 15 essential to achieve weight and purity desired results of the final product.

[0002] The present invention relates to a group of precious metal shot dosing and a system of precious metal shot dosage including the 20 dosing group. Furthermore, the present invention is relating to a method of dosing precious metal.

[0003] State of the art

[0004] In the gold and refinery sectors, it is standard practice consolidated use of precious metal grit, 25 with variable granulometries from 10 mg to 600 mg, as semi-finished product in the production chain. This process It is particularly relevant in the production of ingots of gold, where the first step consists in the creation of grit through melting and casting in water. 5 Subsequently, the grit is dosed with precision to feed a melting furnace that generates the ingot.

[0005] The accuracy of this dosing process is of crucial importance. To ensure that the 10 final ingot contains the exact amount of metal precious, the dosage must be as precise as possible possible, ideally with a maximum deviation of only 10-20 mg in the final weight of the ingot. This level of precision is essential to maintain quality and 15 consistency of the ingots produced, especially in sectors high added value such as jewelry and gold investment.

[0006] Currently, there are available on the market different dosing systems designed to meet the 20 Precision Needs in Ingot Production of gold. The machines used in these known systems represent the standard in the sector and are composed of several key components:

[0007] - one or more hoppers for storing the 25 grit, possibly sifted into granulometries different to ensure a homogeneous distribution of the particles;

[0008] - one or more leaf spring vibrators, designed for the advancement of the grit towards a module of 5 precision weighing;

[0009] - precision weighing modules (scales) which measure the exact quantity of grit dosed;

[00010] - a wire feed and cutting system of precious metal, calibrated to a specific diameter 10 to allow fine adjustment of the final weight.

[00011] The typical operation of these systems provides an initial approach to the target weight through the dosing of the grit, followed by cutting of a segment of precious metal wire of length 15 appropriate to reach the desired weight.

[00012] Although these existing dosing systems have demonstrated their effectiveness in many applications, however, present significant disadvantages. One of the most significant problems concerns the 20 management of precious metal wire used for the final weight adjustment. This thread, which must be produced manually with particular attention to diameter, introduces several problems into the process productive. 25

[00013] First, the production of the thread itself It is laborious and expensive. The process requires an intervention manual to ensure that the thread is produced according to the correct specifications, which may vary depending on the specific requirements of the batch being processed. This does not 5 only increases overall production costs, but It also introduces variability and potential errors in the process.

[00014] Secondly, it is difficult to maintain the traceability of the metal used in the wire 10 compared to the grit used in the same batch. Considering that the wire and grit often come from from different batches of metal, ensure that the ingot final product meets stringent purity standards and composition can be problematic. This lack of 15 Traceability can lead to product inconsistencies final, particularly critical in sectors where the The quality of gold bars is crucial.

[00015] Furthermore, the dependence on the thread for the final weight adjustment adds complexity to the 20 dosing process, increasing the time required for reach the precise weight. This additional step can slow down the entire production cycle, reducing the efficiency of the manufacturing process and increasing the probability of errors. 25

[00016] Summary of the invention

[00017] One of the objects of the present invention is to overcome these limitations by improving the process of dosing the grit until reaching the precision needed to eliminate the need for a 5 refinement by thread.

[00018] A further object of the present invention is to obtain precision in the dosing of the grit, within a predetermined weight tolerance, within a predetermined time frame for 10 each dose. Improving accuracy and efficiency. of the grit dosing system, the invention intends to simplify the production process, reduce the costs and improve overall quality and consistency of the precious metal ingots produced. 15

[00019] This improvement in the dosing system is set to have a significant impact on the industry goldsmith and refinery, providing a more reliable and cost-effective for the production of high quality precious metal ingots 20 qualities.

[00020] The above mentioned purposes are achieved through a dosing group, a dosing system and a method of dosage in accordance with the claims independent claims attached. The dependent claims 25 specify additional optional features advantageous. Description of the drawings

[00021] The features and advantages of the group of dosing, dosing system and method of 5 dosage according to the present invention will result however evident from the description below of some favorite examples of realization, given to indicative and non-limiting title, with reference to the attached figures, in which: 10 - Figure 1 shows an axonometric view of a precious metal ingot production plant including a casting mould transport system of precious metal ingots and a dosing system precious metal granules in accordance with a shape of 15 embodiment of the present invention; - figure 2 shows an axonometric view of a precious metal shot dosing system in agreement to a form of embodiment of this invention; 20 - Figure 3 shows an axonometric view enlarged view of the metal shot dosing system precious of figure 2 in accordance with a form of embodiment of the present invention, wherein are some components have been artificially removed 25 shown in figure 2 for clarity of comprehension; - figure 4 shows an axonometric view enlarged view of the grit dosing system in accordance with to an embodiment of the present invention, 5 where further information has been artificially removed components already shown in figure 2 and figure 3 for greater clarity of understanding; - figure 5 shows an axonometric view enlarged view of the shot dosing system in the figure 10 4 in accordance with an embodiment of this invention, in which they have been artificially removed additional components already shown in figure 4 for greater clarity of understanding; - Figure 6 shows a side elevation view 15 shot dosing system of figure 5; - figure 7 shows an axonometric view of a dosing group according to a form of embodiment of the present invention, in which it has been artificially removed the weighing device for 20 greater clarity of understanding; - Figure 9 shows a front elevation view of the dosing group according to a form of embodiment of the present invention, in which it has been artificially removed the weighing device for 25 greater clarity of understanding; - Figure 10 shows a front elevation view detail of the dosing group in figure 9; - Figure 11 shows a robotic manipulator with a end-effector according to an embodiment 5 of the present invention; - figure 12 shows an end-effector according to an embodiment of the present invention, in a loading configuration of a container collection of precious metal grit; 10 - Figure 12a shows the end-effector of Figure 12 in a closed configuration, in which the container of precious metal grit collection is closed for prevent the release of precious metal grit during handling by the manipulator 15 robotic; - figure 12b shows the end-effector of figure 12 in an open configuration, in which the container of precious metal grit collection is overturned compared to the configuration in figure 12 and is free to 20 unload the precious metal grit into a end-effector funnel device according to an embodiment of the present invention. Detailed description 25

[00022] Although the present invention is described below with reference to preferred forms of realization represented in the drawing tables, The present invention is not limited to the forms of realizations described and represented below 5 in the tables. On the contrary, the embodiments described and represented clarify some aspects of the present invention.

[00023] With reference to the above attached figures, with the reference number 1 it is overall 10 indicated a dosing group 1 metal shot valuable for a metal shot dosing system precious 100 suitable for dosing a quantity of grit of precious metal, for example intended for a bracket 200 for a metal shot melting furnace 15 precious, for the production of metal ingots precious.

[00024] As stated, in this description when reference will be made to a precious metal, it means a metal such as gold or silver or 20 platinum, or palladium, or ruthenium, or rhodium, or osmium, or iridium.

[00025] The dosing group 1 comprises a first container 10, such as a hopper, suitable for contain a first grain of precious metal having 25 a first size and a second container 10' suitable to contain a second grain of precious metal having a second size, different from the first size, preferably a smaller size. For example for example, the first container 10 contains a first 5 coarse-grained precious metal granules, example with grains having an average diameter greater than a millimeter and the second container contains a second finely grained precious metal granules, such as example with grains having an average diameter smaller than 10 millimeter.

[00026] For each of these first container 10 and second container 10', the dosing group includes a respective vibratory device 2, 2' operationally connected to the respective first container 10 and to the 15 respective second container 10' to put it in vibration.

[00027] In the following description, it will be reference to embodiments of the device vibrator 2, 2' with reference to the first container only 20 10, but it is clear that, since each of the said first container 10 and second container 10' is associated with a respective vibrator device 2, 2', what applies to the first container 10 and the related connections to the respective vibrator device 2, also applies to the 25 second container 10' in a similar manner with your own vibratory device, thus duplicating the features and functionality. Therefore, the detailed description which will be given below with reference to the vibrator device 2 with the respective 5 first container 10, applies similarly for a second vibrator device 2' with its own second container 10'. This is also evident from the figures attached.

[00028] The vibrator device 2, 2' may be a 10 mechanical vibrator with eccentrics, or pendulum, or piston, or a pneumatic vibrator, for example a ball, or turbine or piston, or a vibrator electromagnetic.

[00029] In particular, an advantageous form of 15 implementation provides that the vibrator device is a mechanical eccentric vibrator.

[00030] In particular, in accordance with a form of embodiment, the vibrator device 2, 2' comprises a pair of eccentrics 110, 111, rotatably fixed 20 to a support base 112, each suitable for rotation in an eccentric manner around its own tree rotation X1, X2 to vibrate the first one container 10.

[00031] Preferably, the vibrator device 2, 25 2' comprises a base body 113 in which are rotatably inserted in a spaced manner along a longitudinal axis X3 the eccentrics 110, 111, of the pair of eccentrics. The base body 113 is joined to the first container 10 to transmit its vibration. 5 Preferably the base body 113 is joined in a directed to the first container 10 or to the second container 10'.

[00032] Preferably, the eccentric pair 110, 111 and the base body are supported cantilevered with respect to 10 at the support base 112.

[00033] Preferably, the vibrator device 2, 2', comprises an electric actuator 114 operationally connected to the pair of eccentrics 110, 111 to place them in rotation. Preferably, the electric actuator 114 is 15 connected to the eccentric pair by a system belt drive / s 115.

[00034] Preferably, the rotation shafts of the pair of eccentrics 110, 111 are operated by a single drive belt 117. 20

[00035] In accordance with one embodiment, the dosing group 1 comprises at least a first mass of 6 balance mounted on each vibrator device 2, 2' and having a mass such as to dampen the vibrations unwanted and reduce the transmission of 25 vibrations from the first container 10 to the second container 10' or vice versa.

[00036] According to one embodiment the dosing group 1 comprises at least a first mass of balance 6 and a second balance mass 6', 5 wherein the first balancing mass 6 is operationally coupled to a 110 of the eccentric pair and the second balancing mass is operationally coupled with the other 111 of the eccentric pair.

[00037] Preferably, the first mass of 10 balance 6 is mounted on the rotation shaft X2 of a 110 eccentric of the eccentric pair and the second balance weight 6' is mounted on the shaft X1 rotation of the other 111 eccentric.

[00038] Preferably, the first mass of 15 balance 6 and the second balance mass 6' they are a single body with a through hole suitable for being grafted onto the respective rotation shaft X1, X2 of the pair of eccentrics 110, 111. Furthermore, preferably each first balancing mass 6 and second mass 20 of 6' balance has a misaligned center of mass with respect to the central axis of the through hole.

[00039] The dosing group 1 also comprises a weighing device 3, e.g. a load cell or a scale, suitable for detecting the weight of the quantity 25 of first precious metal grain and second precious metal grain present in a container of grit collection 4 and discharged from the first container 10 and from the second container 10'. For example, the grit collection container 4 is a glass 5 arranged in contact with and above the device weighing.

[00040] The dosing group 1 comprises a unit control electronics 5 configured to control the vibrating device 2, 2' based on the weight detected by the 10 weighing device 3 and to send a signal of command to the vibrator device 2, 2' to place in vibrate the first container 10 or the second container 10' to advance the first metal shot precious or the second grain of precious metal in 15 a discharge direction D towards the container of grit collection 4.

[00041] Therefore, the weighing device is configured to send a weight signal grit collection container 4 even during the 20 discharge of precious metal grit into the grit collection container 4.

[00042] The electronic control unit 5 is configured to send a command signal to the 2, 2' vibrator device to move the first one back 25 grit of precious metal or the second grit of precious metal in a retreating direction B, opposite to the direction of discharge D. This allows for control the discharge even more precisely of the precious metal grit, as the 5 imparted backward movement allows for unload the precious metal grit into the 4 grit collection container in a more controlled, grain by grain, without risking discharge too much grit, 10 with the consequent risk of exceeding the weight goal to achieve.

[00043] In accordance with one embodiment, the dosing group 1 of the present invention is preferably without a wire cutting system 15 precious metal to achieve the goal of weight in the grit collection container 4. This is allowed precisely thanks to the control of the device vibrator both in forward and backward motion precious metal grit. 20

[00044] Preferably, the dosing group 1 includes a first evacuation channel 11 joined to the first container 10 and a second evacuation channel 11' joined to the second container 10'. For example, the first evacuation channel 11 and the second channel of 25 evacuation 11' are open channels that are extend preferentially along one direction longitudinal L1, L2. Preferably, the section transverse, perpendicular to the longitudinal direction L1, L2, of the first evacuation channel and of the second 5 evacuation channel is a V-shaped or a U-shaped.

[00045] For example, the backward movement imparted on the first container 10 or on the second container 10' and, consequently, or in a manner 10 independent, on the first evacuation channel 11 and / or on the second evacuation channel 11', allows the arrangement of the grains of the first metal shot precious or of the second grain of precious metal in a single row, without forming stacked grains 15 one on top of the other inside the first or second channel of evacuation 11, 11'. This then allows you to unload one grain at a time inside the container of collection 4 when the vibrator device 2, 2' is operated again in the discharge direction D or, 20 incidentally for some grains, even during the drive in the reverse direction B.

[00046] In accordance with one embodiment, the dosing group 1 also includes a first partialization device 12 associated with the first 25 evacuation channel 11 and a second device 12' partialization associated with the second channel of evacuation 11'. Each of these first devices partialization 12 and second device of 12' partialization is suitable for interaction 5 respectively with the first evacuation channel 11 and with the second evacuation channel 11' to regulate the stream of precious metal grit flowing in each first evacuation channel 11 and second channel evacuation time 11' respectively from the first container 10 10 towards the grit collection container 4 and from second container 10' towards the collection container grit 4.

[00047] In accordance with one embodiment, the first partialization device 12 and the second 15 partialization devices 12' each include a respective shutter operating device 122, 122' and a respective shutter 121, 121'. The portcullis 121, 121' is operationally connected with the respective shutter operating device 122, 20 122' to be moved relative to the respective first evacuation channel 11 or second evacuation channel evacuation 11' and consequently increase or decrease the passage of precious metal grain downstream of the shutter 121, 121' in the direction towards the 25 grit collection container 4. Preferably, the shutter operating device 122, 122' is controllable by a shutter control command sent from the electronic control unit 5 for determine the position of the shutter 121, 121'. To 5 example, the shutter operating device 122, 122' is a hydraulic or pneumatic or electric actuator operationally connected with the shutter 121, 121' for move it with respect to the evacuation channel 11, 11', for example in a direction perpendicular to the 10 direction of discharge (D) of the grit.

[00048] In accordance with one embodiment, the dosing group 1 comprises a dosing device flow detection 7, such as a video camera, suitable to detect a flow signal (e.g. an image 15 or a video or its processing) relating to the flow of precious metal grit in the first channel of evacuation 11 and / or second evacuation channel 11'.

[00049] Preferably, the electronic unit of control 5 is configured to control the device 20 of shutter operation 122, 122' by means of a command gate valve control based on flow signal coming from flow detection device 7.

[00050] Preferably, the electronic unit of control 5 is configured to control the device 25 vibrator 2, 2' to advance the first grain of precious metal or the second grain of metal valuable with increasing speeds and, in case of detection of a stream of lower precious metal grit at a certain pre-established threshold, the unit of 5 control 5 is configured to send a command shutter control to open the door further shutter 121, 121', for example to disengage any grit with an excessively large size big. 10

[00051] In accordance with one embodiment, the dosing group 1 comprises a dosing device filling detection suitable for detecting the filling status filling the first container 10 and / or the second 10' vessel, e.g. a time-of-flight sensor. 15 The electronic unit 5 is then configured to receive a signal relating to the filling status of the first container 10 and / or the second container 10' from of the filling detection device and send a alarm state or trigger a further 20 gate valve discharge device for filling of grit from an additional container.

[00052] As shown in the attached figures, it is clear which is also the subject of the present invention a 100 grit precious metal dosing system 25 comprising a dosing group 1 in accordance with a any of the embodiments described in the This description and a transport system 20 collection containers suitable for transporting the 4 grit collection containers from and to the 5 weighing device 3.

[00053] As can be seen from the attached figures, in according to a variant of implementation, the system of 100g precious metal grit dosage can include comprising more than one dosage group 1 10 in accordance with any of the embodiments described in this description and more than one system transport containers collection 20 suitable for transport the 4 grit collection containers from and towards the weighing device 3. For example, in the 15 figures attached show a dosing system 100 having two dosing groups 2, 2' and two systems of transport 20, 20' in turn served for example by a only robotic manipulator 30. This allows for increase efficiency and production speed. 20

[00054] In the following, therefore, for simplicity's sake, will describe a dosing system with a group of dosing 1 and a transport system 20, but it is clear that the industry expert understands that the characteristics techniques of this dosing group and system 25 transport can be duplicated two or more times in function of needs.

[00055] In accordance with one embodiment, the collection container transport system 20 comprises a base 25 and a supported rotary table 21 5 from the base in a rotatable manner and including seats container 210, 211, 212. Each container seat 210, 211, 212 is suitable to receive a container of grit collection 4.

[00056] Preferably, the rotary table 21 is suitable 10 to be rotated to carry each container seat 210, 211, 212 selectively in the vicinity of the weighing device 3.

[00057] Preferably, each container seat 210, 211, 212 is a through opening in the table 15 rotating.

[00058] Preferably, the rotary table 21 is supported by base 25 in a relatively movable with respect to the weighing device 3 along a vertical direction Y parallel to the axis of 20 rotation table K of the rotary table 21 or along a direction parallel to the gravitational force.

[00059] In this way, the rotary table 21 is suitable to assume a high configuration E, for example shown in figure 4 and figure 6, in which the table 25 rotating is in a high position along the direction vertical Y and in which the container seats 210, 211, 212 they support the weight of the grit collection containers 4 and in which the rotary table can perform a rotation around the axis of rotation of the table K for 5 bring the grit collection container 4 in proximity of the weighing device 3, without therefore obstruct the weighing device 3 during the rotation.

[00060] Furthermore, the rotary table 21 is suitable for 10 assume a lowered configuration L, for example shown in figure 4 on the right, in which the table rotating is in a lowered position along the direction vertical Y, that is, in a lower position than at the elevated position along the vertical direction Y, 15 and in which the container seat 211 is located in proximity of the weighing device 3 does not support the weight of the grit collection container 4, so that the weighing device 3 can measure the weight of the precious metal grit being discharged. 20

[00061] Preferably, the collection container grit 4 comprises an outer lip 410, which protrudes from a side wall 411 of the container grit collection 4 and which is suitable for going on a beating with the container seat 210, 211, 212 when the table 25 rotating is in its elevated configuration E, so as to lift the grit collection container up to the weighing device 3 and thus allow the rotation of the rotary table 21.

[00062] In accordance with one embodiment, the 5 precious metal shot dosing system 100 comprises a robotic manipulator 30 configured for collect and deposit the collection container grit 4 from / to the rotary table 20 and to unload the precious metal grit in a 200 in bracket 10 graphite destined for a melting furnace or elsewhere, for example in an accessory container.

[00063] Preferably, the robotic manipulator 30 comprises an end-effector 31 on which is mounted a pliers 32. On one 321 of the jaws 321, 322 of the pliers 15 32 a funnel device 40 is supported and on another 322 of the jaws 321, 322 is supportable container of grit collection 4.

[00064] According to one aspect of the present invention, the funnel device 40 is itself the subject of the 20 present invention. Furthermore, according to one aspect, also the end-effector 31 itself is the subject of this invention.

[00065] In accordance with one embodiment, the funnel device 40 comprises an internal cavity 25 funnel 41 and an outlet channel 42. In the internal cavity a closing body 43 is installed in the funnel 41 comprising a central region 431 shaped for seal a 4' access mouth of the container grit collection 4 when the access mouth 4' is in 5 beat with the central region 431. In this body of closure 43 is obtained by one or more through openings 432 suitable to allow the passage of grit precious metal towards the internal funnel cavity 41.

[00066] Preferably, the gripper 32 is movable 10 in a closed configuration C, in which the jaws 321, 322 are closed and the 4' access mouth is in beaten with the central region 431 so as to prevent grit from leaking out of the container grit 4, as shown in figure 12a. 15 Furthermore, the clamp 32 can be moved in a open configuration O, in which the jaws 321, 322 are open, the grit collection container 4 and the funnel device 40 are inverted 180° and the mouth access 4' is not in contact with the central region 20 431 so that the release of grit is facilitated precious metal from the 4' access mouth into the cavity inside the funnel 41 and then into the outlet channel 42, as shown in figure 12b.

[00067] In accordance with one embodiment, the 25 central region 431 of the closing body includes a 431' conical central surface suitable for going in hit with the 4' access mouth of the container grit collection 4 when the clamp 32 is in closed configuration C. 5

[00068] Preferably, one or more through openings 432 are obtained around the central region 431 in a more peripheral region of the funnel device 40, so that the central conical surface 431' conveys the precious metal shot towards one or more openings 10 passersby 432.

[00069] Preferably, the through opening 432, is a single annular opening arranged all around the central surface 431' conical, in particular at the base of the central surface 431' conical. 15

[00070] It is clear that it is also the subject of this invention also a method of dosing grit precious metal in a grit collection container 4 up to a pre-established weight goal.

[00071] The grit dosing method includes the 20 following steps, preferably performed in order of as indicated below:

[00072] a) provide a grit dosing system of precious metal 100 according to any of the forms of realization described in this description, 25 in which the first container 10 contains the first precious metal granules and in the second container 10' the second precious metal grain is received, having a size different from the size of the first precious metal grit, preferably one 5 lower size;

[00073] b) activate the vibrator device 2 associated with the first container 10 to advance the first grain of precious metal in the direction of D discharge until a first dose of first is discharged 10 precious metal granules in the container of grit collection 4 that deviates from the objective of weight for a predetermined first quantity, for example that is 12 grams less than the target of preset weight; 15

[00074] c) activate the vibrator device 2 associated with the first container 10 to move the first grain of precious metal in the direction of retreat B for a first time interval of predetermined retreat; 20

[00075] d) activate the vibrator device 2' associated with the second container 10' to advance the second grain of precious metal in the direction of D discharge until a final dose of second discharge is discharged precious metal grit in the container 25 collection of grit 4 in such a way as to reach a total dose of first precious metal grain and second grain of precious metal in the container of 4 grit collection up to the target weight pre-established. 5

[00076] Preferably, at the end of phase c), the method involves a phase, in which at least in one portion terminal of the first evacuation channel 11 or of the second evacuation channel 11', near the grit collection container 4, the arrangement of the 10 grains of the first precious metal grit or second grain of precious metal appears in a single row, without any grains stacked on top of each other on the other, but for example that there is a grain next to it to the next one lying inside the throat of the 15 V- or U-section of the first evacuation channel 11 or of the second evacuation channel 11'. As already described above, this then allows you to unload one grain at a time into the collection container 4 when the device 20 vibrator 2, 2' is activated again in the discharge direction D, ensuring greater precision and dosing accuracy.

[00077] In accordance with one embodiment, the method provides that, before phase d) and after phase 25 c), the following steps are carried out, preferably in the order indicated:

[00078] c1) activate the vibrator device 2' associated with the second container 10' to advance the second grain of precious metal in the direction of 5 D discharge until a first dose of second discharge is discharged precious metal grit in the container collection 4 in such a way as to reach a partial dose of first precious metal grain and second precious metal grit in the container 10 collection 4 that deviates from the weight goal predetermined for a second predetermined quantity, less than the first predetermined quantity, for example so that the partial dose is less than 1.5 grams compared to the weight goal; 15

[00079] c2) activate the vibrator device 2' associated with the second container 10 to move the second grain of precious metal in the direction of retreat B for a second time interval of predetermined retreat. 20

[00080] In accordance with one embodiment, the method provides that, before phase d) and after phase c), the following steps are performed, preferably in the order indicated:

[00081] c0) before phase c1), activate the 25 vibratory device 2 associated with the first container 10 to advance the first grain of precious metal in the direction of discharge D until a second discharge dose of first grain of precious metal in the collection container 4 so as to reach 5 a partial dose of first grain of precious metal that deviates from the pre-established weight goal for a third predetermined quantity, less than the first predetermined quantity and preferably greater than the second predetermined quantity, for example in such a way 10 that the partial dose is 5 grams less than to the weight goal.

[00082] According to one embodiment and example title to better understand the method of dosing, the method involves the following phases in order 15 indicated:

[00083] a) provide a grit dosing system of precious metal 100 according to any of the forms of realization described in this description, in which the first container 10 contains the first 20 coarse grain precious metal grit and in second container 10' the second grit is received precious metal, having a smaller size, that is a finer grain of precious metal;

[00084] b) activate the vibrator device 2 25 associated with the first container 10 to advance the first coarse-grained precious metal grit in the discharge direction D until a first dose is discharged of first grain of precious metal in the container of collection 4 that deviates from the weight target for 5 a first quantity, for example equal to 12 grams, that is in so that the quantity of first metal shot coarse grain precious stone is less than 12 grams compared to the pre-established weight goal;

[00085] c) activate the vibrator device 2 10 associated with the first container 10 to move the first coarse-grained precious metal grit in the retreat direction B for a first interval of predetermined retreat time, for example for a second; 15

[00086] c0) activate the vibrator device 2 associated with the first container 10 to advance the first coarse-grained precious metal grit in the discharge direction D until a second dose is discharged of first grain of precious metal in the container 20 of collection 4 in order to reach a dose partial of first grain of precious metal in the collection container 4 that deviates from the lens of pre-established weight for a third quantity predetermined, for example equal to 5 grams, lower 25 to the first predetermined quantity and preferably greater than a second predetermined quantity, e.g. example so that the partial dose is lower 5 grams less than your target weight;

[00087] c1) activate the vibrator device 2' 5 associated with the second container 10' to advance the second fine-grained precious metal grit in the discharge direction D until a first dose is discharged of second grain of fine-grained precious metal in the collection container 4 so as to reach 10 a partial dose of first grain of precious metal and second grain of precious metal in the container of collection 4 that deviates from the weight target predetermined for a second predetermined quantity, for example example equal to 1.5 grams, less than the first quantity 15 predetermined and preferably also lower than second predetermined quantity, for example in such a way that the partial dose of first metal shot precious and second grain of precious metal both only 1.5 grams lower than the target of 20 peso;

[00088] c2) activate the vibrator device 2' associated with the second container 10 to move the second fine-grained precious metal grit in the retreat direction B for a second interval of 25 preset retreat time, for example for a second;

[00089] d) activate the vibrator device 2' associated with the second container 10' to advance the second grain of precious metal in the direction of 5 D discharge until a final dose of second discharge is discharged fine-grained precious metal grit in collection container 4 so as to reach a total dose of first grain of precious metal and second grain of precious metal in the container 10 of collection 4 equal to the pre-established weight goal, with a margin of error that the industry expert can understand to be due at least to the limits of precision and accuracy of the weighing device 3.

[00090] Innovatively, the present invention 15 allows you to brilliantly overcome the drawbacks cited with reference to the prior art.

[00091] In particular, thanks to the invention, it is made available a dosing group, a system and a dosing method that surprisingly does not require 20 using a metal wire cutting system valuable for reaching your weight goal pre-established.

[00092] In an innovative way this allows to obtain homogeneous precious metal ingot lots and 25 highly traceable.

[00093] Furthermore, thanks to the use of vibrating devices moved both in the direction which favors the discharge of the grit which in the direction that favors the retreat of the grit, 5 so that it is arranged in a row formed by single grains placed next to each other, you can control in an extremely precise manner the quantity of grains discharged into the collection container, thus avoiding possible machine downtime or container waste 10 incorrect weight, thus increasing overall efficiency of the system.

[00094] Furthermore, the dosing group according to The present invention allows to obtain a precision even lower than 10 milligrams with times 15 of the target dose dosage in the container of collection even less than twenty seconds. This is due to the precision and speed of unloading of the precious metal granules thanks to the devices vibrators and the consequent possibility of avoiding 20 the use of precious metal wire cutting, which It is generally a slower operation and is added to the classic operation of unloading the grit.

[00095] Furthermore, the presence is advantageous of balancing masses on the eccentrics allows to 25 have two vibrators placed on the same base without that the vibrations of a vibrating device affect the other container, thus avoiding accidental and unwanted discharges of grit.

[00096] Further advantageously, the end- 5 effectors of the robot equipped with the funnel device allows for quick removal of the collection container 4 and the discharge of the precious metal grit into the respective bracket intended for the oven, without further intermediate steps of release and withdrawal of the 10 collection container. Furthermore, this device funnel allows direct passage of the container collection from the rotary table towards the discharge in the bracket with a single movement of the manipulator robot and without any intermediate pauses for the release 15 and the collection container socket, also avoiding the risk of accidentally discharging grains during any movement of the end-effector, thanks to the sealing of the funnel device.

[00097] It is clear that a technician in the sector, in order 20 to meet contingent needs, could bring modifications to the invention all contained within the scope of protection as defined by the following claims.

Claims

1. Precious metal grain dosing unit (1) for a precious metal grain dosing system (100) suitable for dosing a quantity of precious metal grain for the production of precious metal ingots, wherein said dosing unit (1) comprises a first vessel (10) suitable for containing a first precious metal grain having a first size and a second vessel (10') suitable for containing a second precious metal grain having a second size, different from the first size, preferably a smaller size; wherein, for each of said first vessel (10) and second vessel (10'), the dosing unit comprises a respective vibratory device (2, 2') operatively connected to the respective first vessel (10) and to the respective second vessel (10') to set it into vibration;said dosing unit (1) further comprising: - a weighing device (3), suitable for detecting the weight of the quantity of first precious metal grain and second precious metal grain present in a grain collection container (4) and discharged from the first container (10) and the second container (10'); - an electronic control unit (5) configured to control the vibrating device (2, 2') based on the weight detected by the weighing device (3) and to send a control signal to the vibrating device (2, 2') to cause the first container (10) or the second container (10') to vibrate so as to advance the first precious metal grain or the second precious metal grain in a discharge direction (D) towards the grain collection container (4);said dosing group (1) being characterised in that the electronic control unit (5) is configured to send a control signal to the vibratory device (2, 2') to cause the first precious metal grain or the second precious metal grain to retreat in a retreat direction (B), opposite to the discharge direction (D).; 2. Dosing group (1) according to claim 1, without a precious metal wire cutting system to achieve the target weight in the shot collection container (4).

3. Dosing unit (1) according to claim 1 or 2, comprising at least a first balancing mass (6) mounted on each vibrating device (2, 2') having a mass such as to dampen unwanted vibrations and reduce the transmission of vibrations from the first vessel (10) to the second vessel (10') or vice versa.

4. Dosing unit (1) according to any of the preceding claims, comprising a first evacuation channel (11) connected to the first vessel (10) and a second evacuation channel (11') connected to the second vessel (10'), said dosing unit (1) further comprising a first partialisation device (12) associated with the first evacuation channel (11) and a second partialisation device (12') associated with the second evacuation channel (11'),each of said first throttling device (12) and second throttling device (12') being adapted to interact respectively with the first evacuation channel (11) and the second evacuation channel (11') to regulate the flow of precious metal shot flowing in each first evacuation channel (11) and second evacuation channel (11') respectively from the first vessel (10) towards the shot collection container (4) and from the second vessel (10') towards the shot collection container (4)., 5. Dosing unit (1) according to claim 4, wherein the first partialization device (12) and the second partialization device (12') each comprise a respective gate actuating device (122, 122') and a respective gate (121, 121') operatively connected to the respective gate actuating device (122, 122') to be moved relative to the respective first evacuation channel (11) or second evacuation channel (11') and consequently increase or decrease the passage of precious metal shot downstream of the gate (121, 121') in the direction towards the shot collection container (4).

6. A dosing unit (1) according to claim 5, comprising a flow detection device (7), e.g. a video camera, adapted to detect a flow signal relating to the flow of precious metal shot in the first evacuation channel (11) and / or second evacuation channel (11'), wherein the gate operating device (122, 122') is controllable by a gate control command to determine the position of the gate (121, 121'), and wherein the electronic control unit (5) is configured to control the gate operating device by a gate control command based on the flow signal from the flow detection device (7).

7. Dosing unit (1) according to claim 6, wherein the electronic control unit (5) is configured to control the vibratory device (2, 2') to advance the first precious metal grain or the second precious metal grain at increasing speeds and, in case of detection of a flow of precious metal grain lower than a certain pre-established threshold, the control unit (5) is configured to send a gate control command to open the gate (121, 121') more, for example to dislodge any grain with an excessively large size.

8. Dosing unit (1) according to any of the preceding claims, comprising a filling detection device suitable for detecting the filling state of the first container (10) and / or the second container (10').

9. Precious metal shot dosing system (100) comprising a dosing unit (1) according to any of the preceding claims and a collection container transport system (20) suitable for transporting the shot collection containers (4) to and from the weighing device (3).

10. A precious metal shot dosing system (100) according to claim 9, wherein the collection container transport system (20) comprises a base (25) and a rotary table (21) rotatably supported by the base and comprising container seats (210, 211, 212), each container seat (210, 211, 212) being adapted to receive a shot collection container (4), and wherein the rotary table is adapted to be rotated to selectively bring each container seat into proximity of the weighing device (3).

11. Precious metal shot dosing system (100) according to claim 10, wherein the rotary table (21) is supported by the base (25) in a relatively translatable manner with respect to the weighing device (3) along a vertical direction (Y) parallel to the axis of rotation of the rotary table (21) or along a direction parallel to the force of gravity.

12. A precious metal shot dosing system (100) according to any of claims 9 to 11 comprising a robotic manipulator (30) configured to pick up and deposit the shot collection container (4) from / to the rotary table (20) and to discharge the precious metal shot into a graphite bracket (200) intended for a melting furnace.

13. Precious metal shot dosing system (100) according to claim 12, wherein the robotic manipulator (30) comprises an end-effector (31) on which a gripper (32) is mounted and wherein a funnel device (40) is supported on one (321) of the jaws (321, 322) of the gripper (32) and the shot collection container (4) can be supported on another (322) of the jaws (321, 322), wherein the funnel device (40) comprises an internal funnel cavity (41) and an outlet channel (42), and wherein in the internal funnel cavity (41) a closure body (43) is installed comprising a central region (431) shaped to seal an access mouth (4') of the shot collection container (4) when the access mouth (4') is in abutment with the central region (431), in said closing body (43) one or more through openings (432) being obtained suitable to allow the passage of precious metal granules towards the internal funnel-shaped cavity (41),and in which the gripper (32) can be moved in a closed configuration (C), in which the jaws (321, 322) are closed and the access mouth (4') is in contact with the central region (431) so as to prevent the escape of shot from the shot container (4), and an open configuration (O), in which the jaws (321, 322) are open, the shot collection container (4) and the funnel device (40) are turned upside down by 180° and the access mouth (4') is not in contact with the central region (431) so that the escape of precious metal shot from the access mouth (4') into the internal funnel cavity (41) and then into the exit channel (42) is favoured.

14. Precious metal shot dosing system (100) according to claim 13, wherein the central region (431) of the closure body comprises a conical central surface (431') suitable to abut the access mouth (4') of the shot collection container (4) when the tongs (32) are in the closed configuration (C), and wherein the one or more through openings (432) are obtained around the central region (431) in a more peripheral region of the funnel device (40), so that the conical central surface (431') conveys the precious metal shot towards said one or more through openings (432).

15. Method for dosing precious metal grains into a collection container up to a pre-established target weight, comprising the following steps: a) providing a precious metal grain dosing system (100) according to any of claims 9 to 14, wherein the first precious metal grain is housed in the first container (10) and the second precious metal grain is housed in the second container (10'), having a size different from the size of the first precious metal grain; b) activating the vibratory device (2) associated with the first container (10) to advance the first precious metal grain in the discharge direction (D) until a first dose of the first precious metal grain is discharged into the collection container (4) which deviates from the target weight by a first pre-determined quantity, for example which is 12 grams less than the pre-established target weight;c) activate the vibratory device (2) associated with the first container (10) to move the first precious metal grain backwards in the backward direction (B) for a pre-established first backward time interval; d) activate the vibratory device (2') associated with the second container (10') to move the second precious metal grain forwards in the discharge direction (D) until a first dose of second precious metal grain is discharged into the collection container (4) in such a way as to reach a total dose of first precious metal grain and second precious metal grain in the collection container (4) up to the pre-established weight target.; 16. The method according to claim 15, wherein, prior to step d), the method comprises the following steps: c1) activating the vibratory device (2') associated with the second vessel (10') to advance the second precious metal grain in the discharge direction (D) until a first dose of second precious metal grain is discharged into the collection container (4) in such a way as to achieve a partial dose of first precious metal grain and second precious metal grain in the collection container (4) that deviates from the predetermined weight target by a second predetermined quantity, less than the first predetermined quantity, for example such that the partial dose is 1.5 grams less than the weight target;c2) activate the vibratory device (2') associated with the second container (10) to make the second precious metal grain retreat in the retreat direction (B) for a second pre-set retreat time interval.; 17. Method according to claim 16, wherein, prior to step d), the method includes the following step: c0) prior to step c1), activating the vibratory device (2) associated with the first vessel (10) to advance the first precious metal grain in the 5 discharge direction (D) until a second dose of the first precious metal grain is discharged into the collection container (4) in such a way as to reach a partial dose of the first precious metal grain in the collection container (4) which deviates 10 from the predetermined weight target by a third predetermined quantity, lower than the first predetermined quantity and preferably higher than the second predetermined quantity, for example in such a way that the partial dose is 5 grams lower than 15 the weight target.