WO2024009152A1

WO2024009152A1 - Electronic board disassembly unit and electronic board disassembly method

Info

Publication number: WO2024009152A1
Application number: PCT/IB2023/055362
Authority: WO
Inventors: Marco Guolo; Alice TORI; Mario DEMARIE; Andrea MASTROCINQUE; Fabio STRATTA
Original assignee: Osai Automation System S.P.A.
Priority date: 2022-07-04
Filing date: 2023-05-25
Publication date: 2024-01-11

Abstract

An electronic board disassembly unit (1) is described; the unit (1) comprises a frame (2), a body (3) rotating in relation to the frame (2) about a first axis (A) of rotation and comprising a chamber (4) adapted to contain a plurality of electronic boards to be disassembled, and heating means (5) for heating the chamber (4); the body (3) comprises a plurality of openings (7) adapted to allow the detached components to exit the chamber (4) and to prevent the exit of the electronic boards or elements of the electronic boards having dimensions exceeding a threshold value.

Description

"ELECTRONIC BOARD DISASSEMBLY UNIT AND ELECTRONIC BOARD

DISASSEMBLY METHOD"

Cross-Reference to Related Applications

This Patent Application claims priority from Italian Patent Application No . 102022000014146 filed on July 4 , 2022 , the entire disclosure of which is incorporated herein by reference .

Technical Field

The present invention relates to an electronic board disassembly unit and method .

State of the Prior Art

Waste electrical and electronic equipment generally contains valuable materials of various types , for example precious metals and rare earths , which can be reused as secondary raw materials in new production processes .

Therefore , plants are well known for carrying out processes for recycling electronic equipment waste , in particular electronic boards .

Speci fically, electronic boards comprise a printed circuit and a plurality of electrical or electronic components fixed to the printed circuit .

In order to recover the valuable materials from the electronic boards , it is first of all necessary to disassemble them, which consists in removing the components from the relative printed circuits . The components and printed circuits are then subj ected to mechanical or thermomechanical processes for the extraction of the recoverable raw materials .

However, in order for the recycling of the electronic boards to be cost-ef fective , it is important that the disassembly and sorting of the parts resulting from the disassembly take place quickly and ef ficiently .

There is therefore a need to provide a device for the disassembly of the electronic boards and the sorting of the parts resulting from such disassembly in a simple and cost- ef fective way .

The obj ect of the present invention is to solve the technical problem described above .

Summary of the Invention

Said obj ect is achieved by means of an electronic board disassembly unit according to claim 1 and an electronic board disassembly method according to claim 10 .

Brief Description of the Drawings

For a better understanding of the present invention, a preferred embodiment is described below by way of nonlimiting example and with reference to the accompanying drawings , wherein :

- Figure 1 is a schematic perspective view of a recycling plant for electronic boards comprising an electronic board disassembly unit according to the present invention;

- Figure 2 is a flow chart relating to the operation of the plant in Figure 1 ;

- Figures 3 and 4 are perspective views of the electronic board disassembly unit in Figure 1 according to respective di f ferent viewpoints ; and

- Figure 5 is a perspective view of a portion of the unit shown in Figures 1 , 3 and 4 on an enlarged scale and with parts removed for clarity .

Detailed Description of the Invention

With reference to Figure 1 , the numeral 100 indicates a recycling plant for electronic boards , i . e . , for the recovery of secondary raw materials contained in the electronic boards .

Hereinafter, an electronic board is understood as a hardware component comprising a printed circuit board ( PCB ) and a plurality of electrical and/or electronic components fixed to the printed circuit .

Speci fically, the components can be fixed to the printed circuit by soldering, clinching, through-hole technology, or mechanical connection ( e . g . , by screws ) .

In addition, electronic board disassembly is understood as the detachment of the electronic components from respective printed circuits . Printed circuits typically vary in si ze from 100 x 60 mm at a thickness of approximately 1 mm to 600 x 600 mm at a thickness of approximately 5 mm . Furthermore , the electronic components generally have at least one of the three dimensions smaller than 30 mm .

The plant 100 essentially comprises :

- a loading unit 50 for loading the electronic boards to be recycled; and

- a unit 1 for disassembling the electronic boards loaded into the loading unit 50 .

As shown in Figure 5 , the unit 1 comprises :

- a frame 2 ;

- a body 3 rotating in relation to the frame 2 about an axis A of rotation and defining a chamber 4 adapted to contain a plurality of electronic boards to be disassembled; and

- heating means 5 for heating the chamber 4 .

Advantageously, the body 3 comprises a plurality of openings 7 such as to allow the electronic components detached from the electronic boards to exit the chamber 4 , but such as to prevent the passage of electronic boards or elements thereof having dimensions exceeding a threshold value . In detail , the threshold value is comparable to the si ze of the electronic components .

Electronic board elements having dimensions exceeding the threshold value could be , for example , printed circuits .

Therefore , since printed circuits are generally larger than typical electronic component si zes , the body 3 acts as a screen for separating the electronic components detached from respective printed circuits .

In the case shown herein, the body 3 comprises two axial ends 3a and 3b, opposite each other, and a cylindrical surface 3c with axis A extending between said axial ends 3a and 3b . The openings 7 extend through the body 3 radially to the axis A at the cylindrical surface 3c .

Furthermore , the openings 7 are square or substantially square in shape and are preferably identical to each other .

The threshold value depends on the si ze of the openings 7 . Preferably, the openings 7 range in si ze from 20 x 20 mm to 60 x 60 mm . These dimensions are measured, for each opening 7 , along respective planes tangent to the cylindrical surface 3c at the opening 7 . For example , the openings 7 are 30 x 30 mm in si ze .

As shown in Figure 5 , the body 3 comprises a plurality of series 8 of openings 7 . Each series 8 comprises a plurality of openings 7 aligned with each other along a circumferential direction in relation to the axis A. In addition, the series 8 are spaced from one another parallel to the axis A. In other words , the body 3 is perforated throughout the entire cylindrical surface 3c . The body 3 further comprises an opening 10 at the axial end 3a and an opening - not shown - at the axial end 3b .

The opening 10 allows the printed circuits separated from the electronic boards within the chamber 4 to be unloaded from the same chamber 4 .

The opening 10 is circular in shape , centred in relation to the axis A, and of suf ficient si ze to allow the passage of the electronic boards and printed circuits . In the embodiment shown herein, the opening 10 is smaller than the si ze of the chamber 4 radially in relation to the axis A.

Preferably, the unit 1 comprises a cover - not shown - at the opening 10 . The cover can be moved between a first position, in which it completely covers the opening 10 , and a second position, in which it at least partially uncovers the opening 10 . In detail , the cover in the second position allows the printed circuits separated from the electronic boards inside the chamber 4 to be unloaded .

Moreover, the opening at the axial end 3b has dimensions such as to allow the electronic boards to be loaded for disassembly in the chamber 4 .

The unit 1 further comprises a container 9 , which houses , within, the body 3 ( Figures 3 and 4 ) . In the case shown herein, the container 9 has the shape of a parallelepiped and defines an internal volume in which the body 3 is positioned . In particular, the chamber 4 is fluidically connected to the rest of the internal volume of the container 9 by virtue of the fact that the body 3 includes the openings 7 and 10 .

The container 9 , in turn, comprises :

- a base wall 9a ;

- a top wall 9b , which is opposite the base wall 9a along a direction Z orthogonal to the ground on which the frame 2 rests ; and

- a plurality of side walls 9c, which extend between the base wall 9a and the top wall 9b along direction Z .

The base wall 9a is arranged immediately below the body 3 along direction Z and is movable between : a closed configuration, in which it closes the internal volume of the container 9 ; and

- an open configuration, in which it places the internal volume of the container 9 in fluidic communication with the outside .

The base wall 9a in the closed configuration is suitable to collect the detached components that exit the chamber 4 through the openings 7 .

The unit 1 also comprises a collection element 6 arranged directly below the base wall 9a along direction Z and designed to collect the components detached from the electronic boards . The collection element 6 is designed to collect the components accumulated on the base wall 9a by gravity when the latter is arranged in the open configuration .

In the case shown herein, the collection element 6 is a collection compartment , which can preferably be removed from the unit 1 . According to a variant , not shown, the collection element 6 comprises a conveyor belt .

The unit 1 further comprises actuation means 20 operatively connected to the body 3 in order to rotate it about the axis A. Speci fically, the actuation means 20 comprise ( Figure 5 ) :

- an electric motor 21 ; and

- a first motion transmission element 22 operatively connected to the electric motor 21 to receive the mechanical energy generated by the motor 21 .

The body 3 also includes a second motion transmission element 23 , which is operatively connected to the first transmission element 22 ( Figure 5 ) .

In the case shown herein, the first motion transmission element 22 comprises a toothed wheel operatively connected to the electric motor 21 in order to be driven into rotation about an axis C parallel to the axis A. The second motion transmission element 23 comprises a crown wheel at the axial end 3b, which meshes with the toothed wheel of the first motion transmission element 22 .

Accordingly, the actuation of the electric motor 21 causes the toothed wheel of the first motion transmission element 22 to rotate about the axis C and the body 3 to rotate about the axis A. In detail , the crown wheel of the second motion transmission element 23 comprises a plurality of teeth extending radially to the cylindrical surface 3c .

The unit 1 also includes an electronic control unit 60 operatively connected to said electric motor 21 to control the actuation thereof ( Figure 3 ) .

The unit 1 also comprises a collection element 24 for collecting the printed circuits obtained as a result of the detachment of the electronic components from the electronic boards . In detail , the collection element 24 is aligned with the body 3 along a direction X orthogonal to direction Z and is arranged close to the opening 10 .

In the case shown herein, the collection element 24 is a collection compartment , which can preferably be removed from the unit 1 . According to a variant , not shown, the collection element 24 comprises a conveyor belt .

The body 3 is tiltable with respect to the frame 2 about an axis B orthogonal to the axis A. In detail , the body 3 is tiltable so as to raise the end 3b with respect to the end 3a parallel to direction Z . In further detail , when the end 3b is farther than the end 3a from the ground on which the frame 2 rests , the electronic boards and printed circuits tend to slide towards the collection element 24 through the opening 10 by gravity .

The unit 1 compri ses tilting means 40 for automatically tilting the body 3 . In detail , these tilting means 40 comprise a linear actuator 41 ( Figures 3 to 5 ) . The linear actuator 41 is preferably of the electric type . Alternatively, the linear actuator is of the pneumatic type . In the embodiment shown, the linear actuator 41 is opposite the collection element 24 in relation to the body 3 along direction X .

The linear actuator 41 , in turn, comprises a cyl inder 42 fixed to the frame 2 and a rod - not shown - which can slide within the cylinder 42 and is operatively connected to the body 3 . In detail , the sliding of the rod causes the body 3 to rotate about the axis B .

The electronic control unit 60 is also operatively connected to the linear actuator 41 to control the sliding of the rod and hence the tilting of the body 3 in relation to the axis B .

The heating means 5 comprise two heaters 30 which are designed to heat the air contained within the container 9 and hence within the chamber 4 . In the case shown herein, the heaters 30 are arranged side by side along direction X . Furthermore , the two heaters 30 are arranged side-by-side with the body 3 along a direction Y orthogonal to directions X and Z . The heating means 5 further comprise ( Figure 3 ) :

- a blower 31 adapted to generate a high-kinetic-energy flow of air ; and

- delivery pipes 32 , which fluidically connect the blower 31 to the heater 30 .

The delivery pipes 32 are designed to impinge the heaters 30 with the air flow generated by the blower 31 and thus trigger a forced convective f low of hot air inside the chamber 4 .

The heating means 5 are suitable for heating the air contained in the chamber 4 to a temperature such as to allow and/or favour the detachment of the electronic components from the printed circuits by reaching the melting temperature of the solder paste adapted to solder the components to the printed circuit . Speci fically, this temperature is greater than or equal to 250 ° C, i . e . , the melting temperature of tin .

The heating means 5 also comprise a return pipe 33 , which fluidically connects the chamber 4 to the blower 31 . This return pipe 33 allows the forced recirculation of the air contained within the internal volume of the container 9 towards the blower 31 . The return pipe 33 contributes to maintaining a constant temperature within the chamber 4 and assists in reaching the process temperature when starting up the unit 1 . The electronic control unit 60 is operatively connected to the heating means 5 and is conf igured to control them in order to vary the temperature in the chamber 4 .

The unit 1 also includes a scale - not shown - for weighing the electronic boards to be inserted in the chamber 4 . In detail , the optimal operating parameters of the unit 1 are chosen according to the weight of the electronic boards measured by the scale .

With reference to Figure 1 , the plant 100 further comprises :

- a unit 51 for dividing the electronic components detached from the electronic boards processed by the unit 1 into di f ferent classes ; a unit 52 for further dividing the electronic components divided in the unit 51 into di f ferent classes ;

- a unit 53 for grinding the electronic components ;

- a unit 54 for grinding the printed circuits resulting from the detachment of the electronic components from the electronic boards in unit 1 ; and

- a unit 55 for mechanically separating the copper from the boards ground in unit 54 .

In detail , the unit 51 is configured to sort the electronic components through a physical/mechanical selection process . The unit 51 is configured to divide the electronic components de-soldered by the unit 1 into different classes of components and a residual fraction. In the present case, the unit 51 is configured to divide the electronic components into two classes A, B and the residual fraction (block S3 in Figure 2) . The residual fraction includes components or portions of components that do not belong to either class A or class B. However, the unit 51 could be configured to divide the electronic components into more than two classes.

The unit 52 is configured to sort the electronic components divided by the unit 51 (e.g., components of classes A and B) into further different classes and a residual fraction. In detail, the unit 52 is configured to carry out the sorting by means of an optical recognition process. In the present case, the unit 52 is configured to further divide the components of classes A and B into four further different classes AA, AB, BA, BB (block S4 in Figure 2) . In more detail, classes AA, AB, BA, BB correspond to components containing different precious metals. The unit 52 could, however, be configured to further sort the components divided by the unit 51 into more than four classes.

The unit 53 is configured to grind the electronic components removed from the electronic boards in the unit 1. In detail, the electronic components that have been ground in the unit 53 could be divided into classes following the division made in the unit 51 and/or unit 52. In addition, the unit 55 is configured to obtain powdered copper and chopped fibreglass (block S5 in Figure 2 ) .

In the embodiment shown herein, the units 50 , 1 , 51 , 52 and 53 are aligned in succession with one another along a direction F . The units 54 and 55 are aligned with one another along a direction G substantially parallel to direction F . Preferably, moreover, the units 1 and 51 are integrated with each other .

The transport of the electronic components , printed circuits and electronic boards between the units 50 , 1 , 51 , 52 , 53 , 54 and 55 takes place manually or automatically, for example by means of one or more conveyors .

The operation of the plant 100 is described below . In use , a certain number of electronic boards to be recycled is fed into the loading unit 50 (block S I in Figure 2 ) .

Subsequently, a portion of the electronic boards contained in the loading unit 50 i s trans ferred to the unit 1 (block S2 ) and weighed by the scale . After weighing, a suitable number of electronic boards is loaded into the chamber 4 . Preferably, the operations of loading the chamber 4 with the electronic boards to be processed take place while the body 3 is rotating about the axis A.

During the rotation of the body 3 , the electronic boards collide with the body 3 itsel f and are hit by the hot air flow generated by the heaters 30 . In particular, the temperature of the air inside the chamber 4 reaches at least 250 ° C .

Due to the temperature reached by the air inside the chamber 4 , which equals or exceeds the melting temperature of the solder paste , and the mechanical shocks suf fered by the electronic boards during the rotation of the body 3 , the electronic components gradually tend to detach from the electronic circuit .

The detached electronic components continue to be moved by the rotation of the body 3 , until they exit through one of the openings 7 and fall by gravity and/or centri fugal force onto the base wall 9a in the closed configuration . Due to the si ze of the openings 7 , the electronic boards and electronic board elements having dimensions exceeding the threshold value continue to be moved inside the chamber 4 .

Periodically, the base wall 9a is automatically shi fted from the closed configuration to the open configuration, and the components collected by the base wall 9a are then gravity-dropped into the collection element 6 .

After a certain time range , the chamber 4 only contains printed circuits with dimensions above the threshold value , which can be unloaded into the collection element 24 . In detail , to facilitate this unloading operation, the body 3 is tilted in relation to the axis B, so that the axial end 3b is raised in relation to the axial end 3a along direction Z . As a result , the printed circuits are slid into the collection element 24 by gravity . Preferably, during the unloading of the printed circuits , the body 3 is rotating about the axis A.

Ultimately, after the unit 1 has completed the operations on the electronic boards (block S2 in Figure 2 ) , the electronic components and printed circuits are separated from each other .

The de-soldered electronic components are then transported into the unit 51 , where they are sorted into classes A and B and a residual fraction (block S3 in Figure 2 ) .

The electronic components sorted by the unit 51 are then transported into the unit 52 , where they are further divided into clas ses AA, AB, BA, BB and a residual fraction (block S4 in Figure 2 ) .

The components of classes AA, AB, BA, BB are then ground separately in the unit 53 (block S5 in Figure 2 ) .

The printed circuits obtained in the unit 1 following the detachment of the electronic components are ground in the unit 54 (block S 6 in Figure 2 ) and then subj ected to a process for mechanically separating copper in the unit 55 (block S7 in Figure 2 ) . At the end of this mechanical separation process , powdered copper and chopped fibreglass are obtained .

The advantages of the unit 1 and the electronic board disassembly method according to the present invention are clear from the above .

Since the body 3 comprises the openings 7 , which can be passed through by the detached electronic components but not by the electronic boards and electronic board elements having dimensions exceeding the threshold value , disassembly of electronic boards can be done quickly and ef f iciently . Indeed, since the electronic boards and printed circuits are generally larger than the electronic components , the unit 1 allows the electronic components to be detached - and at the same time to be kept separate - from the printed circuits .

Since the body 3 is tiltable about the axis B, the operations for unloading the printed circuits into the collection element 24 through the opening 10 by gravity are facilitated .

Furthermore , the electronic boards are loaded into the chamber 4 while the body 3 is rotating about the axis A. As a result , the electronic boards are mixed as soon as they are inserted into the chamber 4 . This makes it possible to uni form the temperatures to which the electronic boards are sub j ected .

Lastly, it is clear that modifications and variations may be made to the electronic board disassembly plant 100 and unit 1 described and illustrated herein without departing from the scope of protection defined by the claims .

In particular, the plant 100 could not comprise the unit 51 and/or unit 52 and/or unit 53 and/or unit 54 and/or unit 55 .

The unit 1 could be composed of separate parts that are connected to each other .

The first motion transmission element 22 and the second motion transmission element 23 could each comprise a crown wheel for a chain transmission rather than a toothed wheel . In this case , the crowns of the first and second motion transmission elements 22 , 23 are operatively connected to each other by means of a chain . Accordingly, the actuation of the electric motor 21 causes the crown of the first motion transmission element 22 to rotate about the axis C and the body 3 to rotate about the axis A via the chain .

The body 3 could be tiltable so as to lower the end 3a with respect to the end 3b parallel to direction Z .

The heating means 5 could comprise a single heater 30 , or more than two heaters 30 . For example , the heating means 5 could comprise four heaters 30 .

The openings 7 could have a shape other than the square one . For example , the openings 7 could be rectangular or circular .

Claims

1.- An electronic board disassembly unit (1) ; each said electronic board comprising a printed circuit and a plurality of components fixed to said printed circuit; said unit (1) comprising :

- a frame ( 2 ) ;

- a body (3) rotating with respect to said frame (2) about a first axis (A) of rotation and comprising a chamber (4) adapted to contain a plurality of electronic boards to be disassembled; and

- heating means (5) for heating said chamber (4) ; characterized in that said body (3) comprises a plurality of openings (7) adapted to allow said components detached, in use, from the respective electronic boards to exit said chamber (4) due to the temperature reached, in use, by the air inside said chamber (4) and the mechanical shocks suffered, in use, by said electronic boards during the rotation of said body (3) ; said openings (7) being also adapted to prevent said electronic boards or elements of said electronic boards having dimensions exceeding a threshold value from exiting said chamber (4) .

2.- The unit according to claim 1, characterized in that said openings (7) have dimensions between 20 x 20 mm and 60 x 60 mm.

3.- The unit according to claim 1 or 2, characterized in that said body (3) is tiltable with respect to said frame (2) about a second axis (B) orthogonal to said first axis (A) .

4.- The unit according to any one of the preceding claims, characterized in that said body (3) comprises:

- a first axial end (3a) and a second axial end (3b) along said first axis (A) , opposite each other;

- a cylindrical surface (3c) extending between said first and second axial ends (3a, 3b) ; said body (3) comprising said openings (7) at said cylindrical surface (3c) and comprising a further opening (10) at said first axial end (3a) ; said further opening (10) being configured to allow the passage of said printed circuits.

5.- The unit according to claim 4, characterized in that said body (3) comprises a plurality of series (8) of said openings (7) at said cylindrical surface (3c) ; each said series (8) comprising a plurality of said openings (7) aligned with one another along a circumferential direction with respect to said first axis (A) ; said series (8) being spaced from one another parallel to said first axis (A) .

6.- The unit according to any one of the preceding claims, characterized in that said heating means (5) comprise :

- at least one heater (30) adapted to heat the air contained in said chamber (4) ;

- a blower (31) adapted to generate a flow of air; and

- delivery pipes (32) , which connect said blower (31) to said at least one heater (30) .

7.- The unit according to claim 6, characterized by further comprising a return pipe (33) , which fluidly connects said chamber (4) to said blower (31) .

8.- A recycling plant for electronic boards, comprising :

- a loading unit (50) for loading electronic boards to be recycled; a first unit (1) for the disassembly of said electronic boards loaded, in use, into said loading unit (50) according to any one of the preceding claims;

- at least one second unit (51, 52) for dividing the electronic components detached, in use, by the first unit (1) into different classes; and/or a third unit (53) for grinding said electronic components; and/or

- a fourth unit (54) for grinding said printed circuits.

9.- The plant according to claim 8 when comprising said fourth unit (54) , characterized by comprising a fifth unit (55) for the mechanical extraction of copper from said printed circuits ground, in use, by said fourth unit (54) .

10.- An electronic board disassembly method; each said electronic board comprising a printed circuit and a plurality of components fixed to said printed circuit; said method comprising the steps of: i) inserting said electronic boards inside a chamber (4) of a body (3) of a unit (1) for the disassembly of electronic boards; ii) heating said chamber (4) through heating means (5) of said unit ( 1 ) ; said method being characterized by comprising the step of : iii) rotating said body (3) with respect to a frame (2) of said unit (1) about a first axis (A) to cause the detachment of said components from the respective electronic boards due to the temperature reached by the air inside said chamber (4) and the mechanical shocks suffered by said electronic boards during the rotation of said body (3) and to cause said detached components to exit said chamber (4) through a plurality of openings (7) of said body (3) ; said openings (7) further preventing said electronic boards or elements of said electronic boards having dimensions exceeding a threshold value from exiting said chamber (4) .

11.- The method according to claim 10, characterized in that said step i) is carried out while said body (3) is rotating about said first axis (A) .

12.- The method according to claim 10 or 11, characterized by comprising the further step iv) of tilting said body (3) with respect to said frame (2) with respect to a second axis (B) orthogonal to said first axis (A) to cause said printed circuits to exit said chamber (4) through a further opening (10) in said body (3) ; said step iv) being carried out while said body (3) is rotating about said first axis (A) .