 |
|
 |
 |
 |
 |
 |
 |
 |
 |
 |
|
Vacuum Release™ (VR) Trays
The Vacuum Release trays (2" and 4") consist of a thin, flexible Gel membrane, which is placed over a mesh material. The Gel holds the device securely in place until it is released "on demand" by applying vacuum to the underside of the tray. The device orientation does not change even during release.Applying a vacuum under the tray causes the Gel membrane to conform to the shape of the mesh, which significantly reduces the surface contact area between the Gel and the device. This temporarily minimizes the Gel holding force for easy device removal.  Devices can be removed with a vacuum pick-up tool once the tray is in the release mode. The hold/release mechanism is reversible and the tray returns to its original holding mode when the vacuum is removed. For best offloading results, a vacuum of 25 Hg is recommended. Gel-Pak's 2" and 4" VR trays, based on industry standard dimensions, are reusable and are ideal for high-volume die handling applications associated with automated equipment such as Alphasem, ASM, BESI/Laurier, Datacon, Dymatix, ESEC, F&K Delvotec, Newport, Palomar, Royce, and custom systems. In order to optimize the offloading performance of the VR tray as a function of device size, Gel-Pak offers a range of mesh geometries: 16, 33, 76, 103, 137, 195. This mesh number (size) corresponds to the number of mesh threads per linear inch so a 16 mesh has very open geometry (wide spacing between threads) while a 195 mesh is extremely dense (close spacing between threads). When the VR tray is placed in release mode, the device will only contact the Gel at the mesh crossover points.  The desired result is to minimize the number of Gel-to-Device contact points while in vacuum release mode in order to minimize the required offload force. Fewer points of contact equates to reduced Gel contact area and thus reduced holding force. At the same time, the mesh spacing (density) must be sufficient to keep the device planar and prevent tilting during unload. The adjoining chart illustrates the recommended mesh size as a function of device size (minimum X,Y dimension) Calculate recommended mesh size for your device along with the maximum number of devices per tray. The number of devices per tray is dependent on tray size, die size, and required device spacing. The standard mesh color is white for all sizes except 195 which uses yellow colored mesh. For automated vision systems that require a darker field of view, black colored mesh is available as a special option on selected sizes. The Vacuum Release Trays are available in black conductive polycarbonate (C) or transparent styrene (T) materials and standard retention levels of XT, XL, X4 and X8. The X8 retention level is only available in the 4" Tray (VR-44) model with size 16 or 33 mesh. Also, the VR-44, which is designed for larger devices, is not available in 76-195 mesh sizes and only comes in the lid configuration (-00B). For the lid configurations (-00B version), the available material types are conductive black (C), transparent (T), and antistatic (AS). The 2" VR trays are packaged either in a hinged box (-02 version) or with a traditional lid cover and clip (-00B version). The 2" hinged box materials are conductive black (C), transparent (T), and antistatic (AS). All of the VR products may be customized with a print pattern (grid) or company logo. Standard available Prints can be viewed at VR Tray Print Options Various VR Tray Accessories are available for both applying vacuum to the VR tray (VRS-24, VHP-24, GP-TrayVac) and unloading the devices (GP-TrayVac, VPV) |
 Unloading Device from VR-44 Tray Using Vacuum Pen      |
|
|
Sitemap Gel-Pak 31398 Huntwood Ave., Hayward CA 94544 Phone 510.576.2220 Fax 510.576.2282 © Copyright 2006, Delphon Industries. |
||
