A Frame type Spring mounts the Heatsink on Micro Processor Unit
Original Publication Date: 2000-Oct-01
Included in the Prior Art Database: 2003-Jun-18
Disclosed is a frame type square spring (spring frame) which have wide opening. The spring is mounted on the print circuit board (PCB) to set the heat sink on MPU in Personal Computer. The flex frame spring gives efficient pressure to the heat sink for better thermal performance. The contact surface of the heat sink is touched directly on the MPU through the wide opening. Fig. 1 shows the basic construction of mechanism. The spring frame (3) has 4 pieces of spacer on the corners. The long screws (2) fix the spring frame (3) through the spacer, and are fastened on the base chassis under the PCB (7). The MPU chip (5) is set on the socket (6) provided on the PCB (7). The thermal rubber (4) is interfaced the heat sink (1) and the MPU (5) for better thermal conductivity. The heat sink (1) provides the heat pipe and FAN for more heat spreading from MPU. It is important for MPU cooling to make the spring frame apply on the component at the right pressure. The spring forth, amount of pressure, is defined as a function of the spring thickness, length and width of spring frame. The spring allows the accumulated tolerance to be minimized while less stress to the MPU. It is not depend on the softness of the thermal rubber. The tolerance creates thermal resistance. As the thermal shim, the soft thermal rubber is effective to reduce air gap and realize better interface. But the compressed thermal rubber cannot solve the tolerance problem because of the thin thickness.