WO2023126687A1

WO2023126687A1 - Nozzle for surface mount technologies, design, manufacturing method and assembly process

Info

Publication number: WO2023126687A1
Application number: PCT/IB2022/050520
Authority: WO
Inventors: Rui Alexandre OLIVEIRA FARIA; José Humberto DA SILVA QUINTELA; Mário José PINTO ANTUNES PINHÃO; Ana Catarina MARTINS MIRANDA; Álvaro Miguel DO CÉU GRAMAXO OLIVEIRA SAMPAIO; António José VILELA PONTES; João Guilherme SILVA DA COSTA VEIGA; Luís Carlos CASTRO SILVA; Susana MACHADO RODRIGUES LIMA; José MENDES MACHADO; José Filipe BIZARRO DE MEIRELES; Maria Teresa MESQUITA CUNHA MACHADO MALHEIRO; Arminda Manuela ANDRADE PEREIRA GONÇALVES; Roberto Carlos FERNANDES SOARES; Tiago Filipe GONÇALVES PIMENTA
Original assignee: Bosch Car Multimedia Portugal, S.A.; Universidade Do Minho
Priority date: 2021-12-30
Filing date: 2022-01-21
Publication date: 2023-07-06

Abstract

The present application describes a three-component nozzle with electrically dissipative behaviour for pickup and placement of equipment that operates with air vacuum force. The proposed nozzle is produced for particular use in Surface Mount Technologies by means of additive manufacturing technologies.

Description

DESCRIPTION "Nozzle for surface mount technologies , design , manufacturing method and assembly process"

Technical Field

The present application describes a three-component noz zle with electrically dissipative behaviour for pickup and placement of equipment that operates with air vacuum force .

Background art

Document US2010/ 0024207A1 entitled "Surface-mount technology noz zle" , describes a SMT noz zle provided for picking up SMD devices . The noz zle includes a suction portion and a supporting arm extending from a side of the suction portion . The suction portion forms an engaging end configured for abutting against the SMD and defines a suction passage with an opening in the engaging end . The supporting arm form at least one supporting end spaced from the engaging end of the suction portion and configured for abutting against the SMD . The invention particularly discloses a noz zle with suction operation and a supporting arm developed to abutting against the surface mount device , this arm abuts on the flat area of the SMD avoiding the uneven areas .

Summary

The present invention describes a noz zle for pickup and placement of surface mount devices comprising a pin and a pipette , fitted together to a mirror ; wherein the mirror comprises a central circular opening which is traversed by a hollow tubular extension of the pin towards an oppositely located hollow tubular extension of the pipette , both pin and a pipette being securely fitted together through a threaded connection system that ensures the firm fitting of the mirror between both pin and pipette which are both comprised of adaptative protrusions to fit said mirror format in the central circular opening .

In a proposed embodiment of present invention, an outer portion of the hollow tubular extension of the pin extends inside of an inner portion of the hollow tubular extension of the pipette though a threaded connection .

Yet in another proposed embodiment of present invention, the pipette comprises a main vacuum channel centrally aligned to a main vacuum channel of the pin that ensures the airtight flow between both the pin and the pipette .

Yet in another proposed embodiment of present invention, the pin is anatomically configured to ensure the connection to a device designed to provide air suction .

Yet in another proposed embodiment of present invention, the pin, the mirror and the pipette comprise at least a combination of Electro-Static Discharge compliant materials .

Yet in another proposed embodiment of present invention, the pipette comprises at least two materials of di f ferent rigidity, a rigid part of the pipette and a flexible part of the pipette .

Yet in another proposed embodiment of present invention, the flexible part of the pipette comprises flexible type material configured to ensure a correct adaptation to an electronic Surface Mount Device component surface , preventing air leakage in this contact area through a pickup and placement procedure .

Yet in another proposed embodiment of present invention, the pipette comprises an air suction point comprised of a flexible part located in the opposite extremity of the threaded connection system of the pipette .

Yet in another proposed embodiment of present invention, the pipette comprises a hollow convergence point between the main vacuum channel and a dual vacuum channel located in the opposite extremity of the threaded connection system of the pipette , which ensures the air flow path between said main vacuum channel and the dual vacuum channel towards two independent air suction points comprised of a flexible part .

The present invention further describes the method of operating a noz zle for pickup and placement of surface mount devices according to the above-described system, comprising the steps of enabling a vacuum air flow to the pin, wherein the vacuum air flow is applied to the main vacuum channel of the pipette which is centrally aligned with a main vacuum channel comprised in the pin; the main vacuum channel distributing evenly the vacuum air flow between two vacuum channels allowing the distribution of the vacuum air flow within actuation zones through contact with flexible portions of the pipette over the flat areas of a surface mount device component avoiding the embossed areas therein located; the surface mount device component being firmly in contact with flexible portions of the pipette ensured by the vacuum air flow is positioned in the deployment location of a printed circuit board; disabling the vacuum air flow to the pin in order to release the surface mount device component .

General Description

The present application describes a noz zle with electrically dissipative behaviour for pickup and placement of SMD devices and/or equipment , operating with air vacuum force , and also the method to produce and assemble said noz zles for SMT process by means of additive manufacturing technologies . The proposed noz zles are developed to operate with vacuum in pickup and placement equipment .

Surface Mount Technologies ( SMT ) are mostly applied in the fabrication of printed circuit boards , being this process composed of several steps , wherein the pickup and placement procedure is responsible for correctly placing the surface mount devices that are going to be further submitted to a soldering procedure . Said equipment perform a sequence of operations during the pickup and placement process which comprise : measure noz zle tip height , vacuum up, vacuum check after pickup, thickness detection of components , tilt detection of components , vacuum check before mount , blow on and mount error check . The main parameters of the equipment relate to speeds and accelerations of the system in production, operating pressures and sensors that allow measurements relevant to the problem to be made .

The existent noz zles can be produced in metal alloys , ceramics and polymers ( elastomers and thermoplastics ) and are composed by two components : a main component and a refractory component . Some of the materials applied in the main component are diamond variations such as polycrystalline diamond and diamond created by physical vapour deposition . The refractory part can be produced with resource to zinc carbide , hafnium carbide , silicon, tungsten or alloys . Noz zle geometries are achieved through electrical discharge machining, milling and turning .

Currently available noz zles fail to ensure the inexistence vacuum leaks between the noz zle and the electronic surface mount device ( SMD) which compromise the pickup and transport of the component from the feeder to the Printed Circuit Board ( PCB ) . In order to minimi ze the ef fect of these leaks it is usual to reduce the pickup and placement speeds which results in a longer production cycle . However, this speed reduction is not always enough, as there are still defects in the placement of the components that lead to higher rej ection rates . There is an increasing variety of electronic components , which implies the constant development of new noz zles that due to the method of development and manufacturing require high time from the moment the need arises until the application of the noz zle on the production equipment .

The present disclosed invention proposes a method to produce noz zles for SMT process by means of additive manufacturing technologies . The proposed nozzles are developed to operate with vacuum in pickup and placement equipment . This solution includes a method to assemble the di f ferent parts of the noz zle .

The developed noz zle can eliminate vacuum leaks , through the incorporation of flexible contact zones in the nozzles by applying soft materials , which when pressed against the component replicates and moulds itsel f to the surface of the component ensuring a perfect adaptative contact without air leaks . The production system of said noz zles allows the customi zation of geometries and the creation of several internal channels for vacuum optimisation ( to distribute the vacuum force through the pickup locations ) that are only possible to achieve through this type of manufacturing . This allows the reduction of development and prototyping times .

Additive manufacturing (AM) technologies allow parts to be produced from 3D models , the model being previously divided into a set of layers which are then built consecutively . This type of manufacturing allows the construction of parts with geometric complexities that would not be po ssible to obtain through subtractive processes . AM processes allow the rapid and versatile production of parts , making it possible to speed up the development process .

There are di f ferent photopolymer options available for the most varied applications , from transparent to rigid and flexible polymers . For this application the main requirement of the material focuses on the electrical properties . In order to avoid damaging the SMD by electrical discharges , the noz zle material responsible for the pickup and placement must be Electro-Static Discharge (ESD) compliant , in other words , be able to trans fer charges between bodies at di f ferent electrostatic potentials caused by direct contact or induced by an electrostatic field .

The proposed manufacturing process through additive manufacturing al lows dif ferent materials to be distributed along the noz zle geometry, achieving the construction of noz zles with di f ferent properties in di fferent areas of the geometry . The additive manufacturing technologies have the accuracy that best adapts to the production of this type of parts , since noz zles for pick and place processes have reduced dimensions . The parts produced by these technologies have a high resolution, as the layer thickness can be up to 16pm . In this type of production process one-step multimaterial products can be achieved .

Brief description of the drawings

For better understanding of the present application, figures representing preferred embodiments are herein attached which, however, are not intended to limit the technique disclosed herein .

Fig . 1 - depicts an embodiment of the proposed layout of the developed noz zle comprised of three components which are assembled together accordingly with the direction of the arrows .

Fig . 2 - depicts an embodiment of the proposed layout of the developed noz zle comprised of the three components assembled together .

Fig . 3 - depicts another embodiment of the proposed layout of the developed noz zle comprised of the three components assembled together , with a diverging mechanical structural arrangement on the pipette , wherein the main vacuum channel is splitted in two channels in the end of the pipette to allow a better contact with SMD devices .

Fig . 4 - depicts another embodiment of the proposed layout of the developed noz zle comprised of the three components assembled together , where the main vacuum channel of the pipette splits in two diverging channels to allow a better contact zone with the SMD with embossed areas.

Description of Embodiments

With reference to the figures, some embodiments are now described in more detail, which are however not intended to limit the scope of the present application.

The developed nozzle is designed for the assembly process of surface mount devices using vacuum force, in the pickup and placement equipment. In order to improve the reduction of leakage between the nozzle and the surface mount device, different internal channels are created. With the same objective, rigid and flexible materials are applied at different areas of the nozzle.

According to an embodiment of the present invention, the proposed developed nozzles, like depicted in Figure 1, consist of three components, the pin (1) , the mirror (2) and the pipette (3) . The pipette (3) is the most important component of the proposed nozzle once it provides an innovative approach to pick up the SMD components. The three components pin (1) , mirror (2) and pipette (3) are assembled together accordingly with the direction of the arrows illustrated in figure 1.

In another embodiment of the present invention, supported by Figure 2, the assembled nozzle comprises the pin (1) , the mirror (2) and the pipette (3) firmly fitted together. The mirror (2) comprises a central circular opening which is traversed by a hollow tubular extension of the pin (1) towards an oppositely located hollow tubular extension of the pipette (3) . The pin (1) and the pipette (3) are securely fitted together through a threaded connection system (21) that ensures the firm fitting of the mirror (2) between both pin (1) and pipette (3) . The pipette (3) comprises at least two materials of different rigidity, a rigid part of the pipette (31) and a flexible part of the pipette (33) . The pipette (3) comprises a main vacuum channel (32) centrally aligned with a main vacuum channel comprised in the pin (1) that ensures the airtight flow between both the pin (1) and the pipette (3) . The flexible portion of the pipette (33) comprises flexible type material configured to ensure a correct adaptation to an electronic Surface Mount Device component surface, preventing air leakage in this contact area through a pickup and placement procedure.

The example of geometry presented in Figure 3, shares most of the similarities of Figure 2, diverging mainly on the mechanical structural arrangement of the pipette (3) that considers a divergence point between the main vacuum channel (32) into two vacuum channels (34) allowing the distribution of the vacuum actuation zones over the flat areas of the component avoiding the embossed areas of the components (4) , as illustrated in Figure 4. The channels (32, 34) produced by, for example Material Jetting technology, are vacuum tight, which makes them suitable for SMT applications. The combination of materials used to produce the nozzle, for example a soft material and a rigid material, allows the required ESD compliance to be achieved. The surface responsible for contact with the component, i.e., the flexible part of the pipette (33) , uses a flexible type material that adapts to the surface of the electronic SMD components, preventing air leakage in this contact area. The pipette (3) and the pin (1) are fitted together to a mirror (2) , said mirror (2) firmly located and fitted in between both components, through a threaded connection system (21) . In one of the proposed embodiments, the main internal channel of the pin (1) comprises approximately 1 mm of diameter, which will ensure the connection point to a machine head providing the suction of the air. In another possible embodiment of the present invention, the pipette (3) will comprise an outer cylindrical diameter of 4.98 mm and a threaded hole M3x0.5 mm. This channel is responsible for connecting the entire vacuum system of the pipette (3) with the vacuum circuit of the machine.

Claims

1. Nozzle for pickup and placement of surface mount devices comprising a pin (1) and a pipette (3) , fitted together to a mirror (2) ; wherein the mirror (2) comprises a central circular opening which is traversed by a hollow tubular extension of the pin (1) towards an oppositely located hollow tubular extension of the pipette (3) , both pin (1) and a pipette (3) being securely fitted together through a threaded connection system (21) that ensures the firm fitting of the mirror (2) between both pin (1) and pipette (3) which are both comprised of adaptative protrusions to fit said mirror (2) format in the central circular opening.

2. Nozzle for pickup and placement of surface mount devices according to the previous claim, wherein an outer portion of the hollow tubular extension of the pin (1) extends inside of an inner portion of the hollow tubular extension of the pipette (3) though a threaded connection.

3. Nozzle for pickup and placement of surface mount devices according to any of the previous claims, wherein the pipette (3) comprises a main vacuum channel (32) centrally aligned to a main vacuum channel of the pin (1) that ensures the airtight flow between both the pin (1) and the pipette (3) .

4. Nozzle for pickup and placement of surface mount devices according to any of the previous claims, wherein the pin (1) is anatomically configured to ensure the connection to a device designed to provide air suction.

5. Nozzle for pickup and placement of surface mount devices according to any of the previous claims, characterized by the pin (1) , the mirror (2) and the pipette (3) comprising at least a combination of Electro-Static Discharge compliant materials .

6. Nozzle for pickup and placement of surface mount devices according to any of the previous claims, wherein the pipette (3) comprises at least two materials of different rigidity, a rigid part of the pipette (31) and a flexible part of the pipette ( 33 ) .

7. Nozzle for pickup and placement of surface mount devices according to any of the previous claims, wherein the flexible part of the pipette (33) comprises flexible type material configured to ensure a correct adaptation to an electronic Surface Mount Device component surface, preventing air leakage in this contact area through a pickup and placement procedure .

8. Nozzle for pickup and placement of surface mount devices according to any of the previous claims, wherein the pipette (3) comprises an air suction point comprised of a flexible part (33) located in the opposite extremity of the threaded connection system (21) of the pipette (3) .

9. Nozzle for pickup and placement of surface mount devices according to any of the previous claims, wherein the pipette (3) comprises a hollow convergence point between the main vacuum channel (32) and a dual vacuum channel (34) located in the opposite extremity of the threaded connection system (21) of the pipette (3) , which ensures the air flow path between said main vacuum channel (32) and the dual vacuum channel (34) towards two independent air suction points comprised of a flexible part (33) .

10. Method of operating a nozzle for pickup and placement of surface mount devices according to any of the previous claims 1 to 9 comprising the steps of enabling a vacuum air flow to the pin (1) , wherein the vacuum air flow is applied to the main vacuum channel (32) of the pipette (3) which is centrally aligned with a main vacuum channel comprised in the pin (1) ; the main vacuum channel (32) distributing evenly the vacuum air flow between two vacuum channels (34) allowing the distribution of the vacuum air flow within actuation zones through contact with flexible portions of the pipette (33) over the flat areas of a surface mount device component avoiding the embossed areas therein located; the surface mount device component being firmly in contact with flexible portions of the pipette (33) ensured by the vacuum air flow is positioned in the deployment location of a printed circuit board; disabling the vacuum air flow to the pin (1) in order to release the surface mount device component.