Pin transfer

Pin- and daub-transfer processes are also mass-transfer methods, but comprise less than 10% of the adhesive-dispensing processes used in production. In pin transfer, hard tooling consisting of an array of pins corresponding to the positions on the circuit board where components are to be attached is fabricated. The pin arrays are dipped into atray containing the 

Pin transfer is the simplest mass-transfer process for high production runs of one or two part types, but limited where numerous t) es of different configurations and small quantities are to be produced. Because pin transfer uses hard tooling, each job requires new tooling and considerable time to set up and change to new tooling. Other limitations of pin transfer are  

Furthermore, surface-mount adhesives (SMAs) used in pin transfer must have relatively low viscosities to facilitate pickup by the pins andtransferto the PCB. Because viscosity is so critical, the temperature ofthe adhesive reservoir must be controlled and preferably maintained between 25°C and SO C.l ] Some SMAs that may be applied by pin transfer are listed in Table 4.17. 

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Figure 6.10 Early example of robotic arm pin transfer tool for printing proteins. (From Lueking, A. et al.. Anal. Biochem., 270, 103-111, 1999. With permission.)...

Pin transfer Surface mount, hybrid, or MCM/bed-of-nails tooling Very fast, consistent Difficult/expensive retooling adhesive handling issues... 

In stamp transfer, a stamping pad is dipped into a reservoir of liquid adhesive and the adhesive redeposited onto a substrate on contact. The amount of material transferred depends on its viscosity, the size and shape of the stamping tool, and the depth to which the stamp is immersed. " An advantage of stamp transfer is the ability to deposit adhesive over large areas in a single application. Pad areas as large as 500-mils square can be covered. However, like pin transfer, limitations of stamp transfer... 

Figure 4.7 Pin-transfer dispensing steps. (The tip of the pin is modified to prevent distorting...

Needle Fluid Jet stencil Print Screen Print Pin Transfer Stamp Transfer Film Bond... 

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