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Heat Sink Mounting System

Heat Sink Mounting System
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Heat Sink Mounting System The new HSCB engineered mounting system provides secure attachment of a heat sink to the circuit board while providing firm contact to the chip component allowing optimum heat dissipation. The three-piece fastening system, sold individually, includes the screw, spring and receptacle nut. The clamp load created is determined by the spring rate and the amount of deflection that is designed into the joint of the hardware. The system also allows for slight expansion and contraction of the joint components without stress to the delicate circuitry. The unique “click” feature lets the user know when the fastener is completely installed. G Patent pending. Features and Benefits • Screw can not be overtightened. Audible “click” when fully engaged. • Screw and spring mount together permanently into the heat sink. • Spring determines clamp force. • Receptacle nut mounts permanently to the PC board. • Provides even, constant contact of heat sink to chip component. • Allows removal of heat sink if desired. To select proper length code of nut/standoff: 1) Determine “G”, the distance from the top surface of the heat sink to the top of the P.C. Board. 2) Find the combination of Screw (HSCB) and Nut (HSR) whose sum of Screw Factor (SF) plus Nut Factor (NF) are closest to G. 3) Find D = G – SF – NF. The D value must be a negative number between zero and 1mm or 1/32” (1 dash length of HSR nut). 4) The actual working load is equal to the Spring (HSL) Working Load + (D x spring rate k). Lower D value results in lower force. If this does not meet your application needs, contact our PEM Technical Support group at techsupport@pemnet.com to develop a special product that matches your specific application. Phillips driver size. TYPE HSCB™ SELF-CAPTIVATING SCREW Part Number Designation HSCB – 440 – 4 Thread Size Code Length Code Threads: External, ASME B1.1, 2A / ASME B1.13M, 6g (1) Material: Hardened Carbon Steel Finish: ZI - Zinc plated, 5µm, colorless (2) For Use In Sheet Hardness: HRB 80 / HB 150 or less (3) NOTE: HSCB screws, HSR nuts and HSL springs are sold separately. Code “L” ±.015 Min. Hole Size Screw Min. Dist Length TS Factor Driver HoleC/L Thread Thread Sheet in Sheet ES H1 H2 Size Type Code .320 Thickness +.003 –.000 ±.010 Ref. Ref. Min. (SF) Size To Edge .112-40 HSCB 440 4 .040 .112 .312 .300 .470 .130 .170 #1 .156 (#4-40) .138-32 HSCB 632 4 .040 .138 .352 .300 .470 .130 .170 #2 .178 (#6-32) Thread Code “L” ±0.4 Length Size x Thread Pitch Type Code 8.13 M3 x 0.5 Hole Size TS in Sheet ES H1 H2 +0.08 ±0.25 Ref. Ref. Min. 3 Screw Min. Dist Factor Driver HoleC/L (SF) Size To Edge (1) As with all Class 2A/6g external threads with an additive finish, the maximum major and pitch, after plating, may equal basic sizes and be gauged to Class 3A/4h, per ANSI B1.1, Section 8, Table 3A and ANSI B1.13M, Section 8, Paragraph 8.2. (2) See PEM Technical Support section of our web site (www.pemnet.com) for related plating standards and specifications. (3) HRB - Hardness Rockwell “B” Scale. HB - Hardness Brinell.

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Heat Sink Mounting System TYPE HSR™ BROACHING NUT/STANDOFF Part Number Designation HSR – 440 – 2 Thread Size Code Length Code Threads: Internal, ASME B1.1, 2B / ASME B1.13M, 6H Material: Carbon Steel Finish: ET - Electro-plated Bright Tin ASTM B 545, Class B With Clear Preservative Coating (1) For Use In Sheet Hardness: HRB 60 / HB 107 or less (2) Thread A Min. Hole Size Nut Min. Dist. Size x Thread Length (Shank) Sheet In Sheet C EN F TN Factor HoleC/L Pitch Type Code Code Max. Thickness +0.08 ±0.08 ±0.13 ±0.25 ±0.13 (NF) Edge To 2 2 .75 M3 x 0.5 HSR M3 1.53 1.53 4.22 4.68 5.56 1.3 4.4 3 3...

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Heat Sink Mounting System INSTALLATION C Type HSCB fastener into heat sink 1. Prepare properly sized mounting hole in heat sink. Do not perform any secondary operations such as deburring. If the hole is punched, be sure to install the fastener into the punch side of the hole. 2. Place the head of the screw into the recess of the installation anvil. 3. Place the spring over the shoulder of the screw, maintaining concentricity. 4. Position the heat sink mounting hole over the screw. 5. Bring the heat sink down over the screw and onto the shoulder of the screw. 6. With the punch and anvil...

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Heat Sink Mounting System PERFORMANCE DATA™ Type HSCB (screw) include using Regulatory compliance information is available in Technical Specifications subject to change without notice. Support section of our website. ©2013 PennEngineering. See our website for the most current version of this bulletin. North America: Danboro, PA USA • E-mail: info@pemnet.com • Tel: +1-215-766-8853 • Fax: +1-215-766-0143 • 800-237-4736 (USA Only) Europe: Galway, Ireland • E-mail: europe@pemnet.com • Tel: +353-91-751714 • Fax: +353-91-753541 Asia/Pacific: Singapore • E-mail: singapore@pemnet.com • Tel:...

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