GB2192492A

GB2192492A - Alignment device for connecting an electronic component to a printed circuit board

Info

Publication number: GB2192492A
Application number: GB8702457A
Authority: GB
Inventors: William D Jordan; Donal L Clemens
Original assignee: Thermalloy Inc
Current assignee: Thermalloy Inc
Priority date: 1986-07-09
Filing date: 1987-02-04
Publication date: 1988-01-13
Also published as: GB2192492B; JPS6319900A; GB8702457D0

Abstract

An alignment device (16) for connecting an electronic component package (14) to a printed circuit board (18) comprises an electrically insulating body having a plurality of holes (36) therethrough to receive the pin connectors (26) of the component and align them with pre-formed holes (28) in the board. A heat sink (12) is releasably engaged in slots (40) in tabs (38) projecting from the device (16) and is also releasably engaged with lugs (20) which pass through slots (30) in the device (16) and are secured in holes (22) in the board. The component (14) is secured to the heat sink (12) by a rivet (24). Numerous modified embodiments are described in the specification. <IMAGE>

Description

SPECIFICATION Alignment device for electronic components This invention relates generally to alignment apparatus for use in mounting electronic components on printed circuit boards. More particularly, this invention relates to alignment devices useful in mounting heat sinks and electronic components having pin connectors and the like on printed circuit boards.

In the assembly of electronic apparatus it is often necessary to position electronic components which have multiple pin connectors on a printed circuit board having preformed locations for receiving the pin connectors. The preformed locations on the printed circuit boards may constitute holes in the printed circuit board, or areas on the surface of the printed circuit board to which the pin connectors may be soldered. Frequently it is also necessary to locate a heat sink on the electronic component so that intimate contact is maintained therebetween.

If it is also necessary to attach the heat sink on the circuit board, this is sometimes accomplished by structures projecting from the heat sink mounted on preformed locations on the circuit board so that the heat sink can be securely attached to the board such as by soldering. More often than not, these structures are separate components from the heat sink and include some releasable arrangement so that the heat sink can be removed when desired. Thus, in orderto mount an electronic component and a heat sink, it is necessary that a multiplicity of pins and structures be aligned with the preformed locations in the circuit board.

In the past, sub-assemblies of parts, such as heat sinks and transistors, were manually assembled and then manually placed with the pins and structures on the appropriate locations in the circuit board. Manifestly, such manual assembly techniques are slow, labour intensive and thus expensive.

Many electronic circuits are currently being assembled by the use of robots and, aftertheelectronic components are placed in the circuit board, mass soldering techniques are utilised so that all the electronic components are soldered to the board simultaneously and virtually instantaneously. Upto now it has remained necessary, because of the alignment problems, to manually assemble the electronic components to their heat sinks and then manually assemblethe sub-assembled parts on the circuit boards.

This invention provides alignment apparatus which premits electronic components and heat sink assemblies to be mounted on the circuit board with all of the pin connectors aligned for engagement with preformed circuit board locations so that the assembly can be made by use of robotictechniques.

Itthus provides alignment apparatus for use in connection with printed circuit boards, heat sinks and electronic components having pin connectors and the like. The apparatus includes an electrically insulating body having a plurality of holes extending through the body for receiving, aligning and retaining the pin connectors in a precise predetermined relationship. The alignment apparatus may additionally include means for releasably connecting the alignment apparatus to the heat sink. The alignment apparatus may include solderable attachment means for attaching the alignment apparatus to the circuit board. Further, the alignment apparatus may include means for securing the electronic component in intimate contact with the heat sink to ensure effective thermal transfer therebetween.

The invention includes the alignment device, the use of the device to mount the component on the printed circuit board, and the method of mounting the component on the board using the alignmentde- vice.

The invention may be carried into practice in various ways, and certain embodiments will now be described by way of example, with reference to the accompanying drawings, in which :- Figure lisa front elevational view of a heat sink, el- ectronic component and alignment device located on a printed circuit board; Figure2 is a cross-sectional view taken generally along line 2-2 of Figure 1; Figure 3 is a top pictorial view of the alignment device of Figure 1; Figure 4 is a bottom pictorial view of the alignment device of Figure 1; Figure 5 is a top pictorial view of an alternative em bodimentofthealignmentdeviceshown in Figure3 and Figure 4; Figure 6is a bottom pictorial view of the alignment device of Figure 5;; Figure 7 is a top pictorial view of anotherembodi- ment of alignment device; Figure 8 is a top pictorial view of still anotheremb- odiment of an alignment device; Figure 9 is a front elevational view of a heat sink, electronic component and still another embodiment ofthe alignment device in which the heat sink is supported generally horizontally over a printed circuit board; Figure 10 is a cross-sectional view taken along line 10-10 of Figure 9; Figure 11 is a top pictorial view of the alignment device of Figure 9; Figure 12 is a bottom pictorial view of the alignment device of Figure 11; Figure 13 is a front elevational view of a heat sink, electronic component, and an alternative alignment device mounted on a printed circuit board;; Figure 14 is a cross-sectional viewtaken generally along line 14-14 of Figure 13; Figure 15 is a top pictorial view of the alignment device of Figure 13; Figure 16 is a bottom pictorial view of the alignment device of Figure 15; Figure 17 is a front elevational view of a heat sink, electronic component an alternative alignment device located on a printed circuit board; Figure 18 is a cross-sectional view taken generally along line 18-19 of Figure 17; Figure 19 is a top pictorial view of the alignment device of Figure 17; Figure 20 is a bottom pictorial view of the alignment device of Figure 17; Figure 2 1 is a top view of the body of the alignment device of Figure 17;; Figure 22 is a side view of the body ofthe align ment device of Figure 17; Figure 23 is a front view of the attachmentmem- eber of Figure 17; Figure 23A is a detailed frontview of an alternative embodiment of one of the mounting tabs ofthe attachment memeber of Figure 23; Figure 24 is a side view of the attachment member of Figure 17; Figure 24A is a detailed cross-sectional view of another alternative embodiment of one ofthe mount ing tabs of the attachment member of Figure24; Figure 25 is a side view partially in cross-section of another embodiment of the alignment device of Figure 17;; Figure 26 is a front elevational view of a heatsink, electronic component and another alignment device located on a printed circuit board; Figure 27 is a cross-sectional view taken generally along line 27-27 of Figure 26; Figure 28 is a top pictorial view of the alignment device of Figure 26; and Figure 29 is a bottom pictorial view of the align mentdevice of Figure 28.

Referring to the drawing and Figures 1 and 2 in particular, shown therein and generally designated by the reference character 10 is a sub-assembly consisting of a heat sink 12, an electronic component, such as atransistor 14, aiignmentdevice 16 and a printed circuit board 18.

The heatsink 12 is generally constructed from a material of high thermal conductivity such as aluminum oralloysthereof. The heatsinkis usually anodized and thus is virtually impossible to solder.

To attach the heat sink 12 to the circuit board 18, solderable attachment means, such as a pair of lugs 20 are reieaseably connected to the heat sink 12 and projectthrough holes 22 preformed in the circuit board 18. The lugs 20 are tinned so thatthey can be quickly and easily soldered to metal patterns and circuit paths on the board 18.

The transistor 14 (or other electronic component having pin or blade type connectors) is attached to the heat sink 12 by a rivet 24 or other suitable means for holding the transistor 14in intimate contact with the heatsinkto obtain effective heattransfertherebetween. As shown, thetransistor 14 includes a plurality of pin connectors 26 which extend through preformed holes 28 in the circuit board 18.

The preformed holes 22 for the lugs 20 and the preformed holes 28forthe pin connectors 26 are auto matically punched into the board 18 and are located therein with greataccuracy so that the components will be properly located to form the desired circuits.

To assurethatthe lugs 22 and the pin connections 26 are positioned to match the location ofthe preformed holes 22 and 28, the alignment device 16 is preferably molded of an electrically insulating material and necessary holes and slots located therein so thatthe relationship of all the holes will be maintained with great accuracy, such as within plus or minus 0.003 inch. Alternatively, and as previously described herein, the lugs could be adapted forsoldering to preformed areas on the surface of the printed circuit board.

The alignment device 16 illustrated in Figures 1 and 2 is shown in more detail in the pictorial views of Figures 3 and 4. As shown therein, the alignment device 16 includes a body constructed as previously described. The body has slots 30 located on each end thereoffor receiving the lugs 20 and retaining them in close alignment. The body also includes a top surface 32 and a bottom surface 34through which a suitable number of pin holes 36 extend. The shape, arrangement and size of the pin holes 36 is determined by the electronic component with which the alignment device 16 is to be used.

Means are provided to releasably connect the bodyto the heat sink. Projecting upwardly from the top surface 32 are a pair of spaced tabs 38 forming the connection means. Each tab 38 includes a slot 40 for receiving an edge of the heat sink 12. On the bottom surface 34 the alignment device 16 is provided with a plurality of protuberances 42 to space the body of the alignment device 16 a small distance away from the surface of the printed circuit board 18.

As in the other embodiments ofthe invention described hereinafter, the protuberances provide access to the underside ofthe alignment device such as for cleaning afterflowsoldering procedures.

Figures 5 and 6 illustrate a modified form ofthe alignment device 16 designated by the reference character 116. As shown in Figure 5, the alignment device 116 includes pin holes 136 which extend through an upper surface 132 thereof and through a bottom surface 134. A pair of spaced tabs 138 con stitute the connection means, having slots 140 therein projecting upwardlyfrom the upper surface 132. The slots 140 are arranged to receive an edge of the heat sink 12 when assembled therewith as described in connection with the assembly of heat sink 12 intheapparatus l0ofFigurel.

In the bottom pictorial view of Figure 6, it can be seen thatthe alignment device 116 also includes a plurality of protuberances 142 arranged to space the body of the alignment device 11 from the surface of the circuit board 18. In that view it can also be seen that the alignment device includes solderable attachment means in the form of a pair of solderable locator lugs 120 extending from the bottom surface 134.

The lugs 120 may be attached to the body ofthe alignmentdevice 116 by pressing the lugs 120 into the device 116 or by molding the lugs 120 into the device 1 during the molding operation.

The purpose of the lugs 120 is to extend through the iocator holes 22 in the circuit board 18 to position the alignment device 116 properly so that the pin holes 136 and pins 26 align properly with the holes 28 in the circuit board 18. The lugs 120, being located in the device 116 but not directly attached to the heat sink, also electrically insulate the heat sink from the circuit board.

Figure 7 illustrates another embodiment of align- ment device designated by the reference character 216. As illustrated therein, the alignment device 216 includes pin holes 236 appropriately arranged and configured to receive an electronic component such as transistor 14. Projecting from an upper surface 232 of the alignment device 216 are three spaced tabs 238, 240 and 242 forming the connection means.

The tabs are located in an alternating arrangementto receive the heat sink 12 between the tabs 238 and 242 on one side and the tab 240 which is located on the opposite side thereof.

It will also be noted that tab 240 includes a stud 244 which projects relatively toward tabs 238 and 242.

The stud 244 is provided to releaseably connectthe alignment device 216 to the heat sink by inserting the stud 244 into a hole (not shown) in the heat sink. In addition, similar studs could be formed on tabs 238 and 242, if desired, for engagement with aligned holes (not shown) in the heat sink.

As illustrated, the alignment device 216 does not include the slots 30 of Figure 3 nor does it include the studs 120 of Figure 6. It should be understood, how- ever, that the alignment device 216 may be provided with either arrangement if desired.

The embodiment of Figure 8 illustrates an alignment device 316 including appropriately arranged pin holes 336. Projecting from an uppersurface332 ofthe device 316 are a pairof spaced tabs 338 and 340 forming the connection means. As illustrated, the tabs 338 and 340 are located on opposite edges of the top surface 332 generally straddling the pin holes 336. Tab 338 includes a ledge 342 on the side of tab 338 facing tab 340 which preferably extends the width of the tab 338. The ledge 342 is located to overlap and engage the top edge of an electronic component such as transistor 14 so thatthe component is secured and retained on the alignment device 316.

The tab 340 is provided with a stud 344 arranged to projectthroughahole(notshown)intheheatsink and latch the heatsinkin position on the alignment device 316. When the transistor 14 is sub-assembled with the heat sink 12 and placed into the space between tabs 338 and 340 the alignment device 316and sub-assembly are securely attached. As mentioned in connection with the embodiment of Figure 7, the locator lugs are not shown on the device 316. Itwill be understood that locator lugs of the type illustrated in Figure 1 and 2 orofthetype illustrated in Figure6 may be used as desired.

Referring now to Figures 9 and 10, the reference character 400 refers to a sub-assembly consisting of a heat sink402, electronic device package 403 and another alternate embodiment of the alignment device 404 ofthis invention; and a printed circuit board 406. As shown, electronic component 403 is a modified TO-220type component package such asthe Mu It-Watts component manufactured by SGS Semiconductor Corporation having two parallel rows of fifteen pin connectors or leads 408 extending from either longitudinal edge thereof. The electronic component package is secured to the heat sink such as by screw or rivet 410 extending through both the package and the heat sink.The heat sink is supported above the printed circuit board in a horizontal posi tion by a solderable nut 412 having an internally threaded aperture extending therethrough. The solderable nut may be soldered into a preformed hole 414 in the printed circuit board or, alternatively, sol dered to the surface of the printed circuit board, as previously described. The solderable nut is aligned with a preformed hole 416 in the heat sink and secured such as by the screw 410 orthe like. Alternatively, solderable studs or any other suitable means may be used to horizontally mount the heat sink on the printed circuit board.

Alignment device 404 is shown in greater detail in the pictorial views of Figures 11 and 12. The alignment device inciudes a body 418 constructed of electrically insulating material as previously described but omitting the solderable attachment means and connection means shown in Figures 1-8. The body includes a longitudinal section 419 having hole 420 foralignmentwith solderable nut 412 and hole 416 in the heat sink. If desired, more than one solderable nut may be employed with a like number of aligned holes formed in the body of the alignment device.

Shoulder 422 is formed in the body to accommodate stand-off portion 424 of the solderable nut. The body may also include a plurality of protuberances 426 on its undersideforspacingthebodyfromthesurface of the printed circuit board. The body includes a plurality of preformed pin holes 428 extending through the body in two parallel rows for receiving the pin connectors of the electronic component, re taining them in a predetermined relationship and aligning them with the printed circuit board. Transverse shoulder 430 is formed and adapted to register against an edge of the heat sinkto position the body of the alignment device with respect thereto.Of course, the alignment device ofthis embodiment could be modified so asto be employed with a heat sink mounted on the printed circuit board in an upright manner or at various angular configurations.

Referring now to Figures 13 and 14, the reference character 510 refers to a sub-assembly consisting of a heatsink512, electronic component 513 and yet another alternate embodiment ofthe alignment de vice 514 of this invention; and a printed circuit board 516. Electronic component 513 is similar to component403 in Figures 9 and 10 and includes two parallel rows having fifteen pin connectors or leads 518ex- tending from either longitudinal edge thereof. The electronic component package is secured to the heat sink such as by screw or rivet 520 extending through both the package and the heat sink.As in the embodiments shown in Figures 9 and 10, the heat sink is supported above the printed circuit board in a horizontal position by one or more solderable nuts 522 having an internally threaded aperture extending therethrough. The solderable nuts may be soldered into preformed holes 524 in the printed circuit board or, alternatively, surface soldered to the printed circuit board as previously described. The solderable nuts are aligned with preformed holes 526 in the heat sink and secured such as by a screw 520 orthe like.

Alternatively, solderable studs or any other suitable means maybe used to mountthe heatsinkonthe printed circuit board.

Alignment device 514 is shown in greater detail in the pictorial views of Figures 15 and 16. The alignment device includes a body 528 constructed as previously described. The body includes a longitudinal section 529 having holes 530 for alignment with one or more solderable nuts 522 and a like number of holes 526 in the heat sink. Shoulder 532 is formed in the body to accommodate stand-off portion 534 of the solderable nut. The body may include a plurality of protuberances 536 on its underside for spacing the bodyfrom the surface of the printed circuit board and includes a plurality of preformed pin holes 538 extending through the body in two parallel rows for receiving the pin connectors of the electronic component, retaining them in a predetermined relationship and aligning them with the printed circuit board.

Transverse shoulder 540 is formed and adapted to register against an edge of the heat sinkto position the body of the alignment device with respect thereto.

Means are also provided to releasably connectthe body to the heat sink. In the embodiment illustrated in Figures 13-16, the connection means includes a spaced pair of resilient fingers 550, each terminating in stud 552. The fingers straddle the longitudinal section and are adapted to engage aligned holes 556 in the heat sink. The heat sink may be released from the alignment device, if desired, by deflecting the fingers and extracting the studs from the holes. Stud 548 is formed on longitudinal section 519to assist in supporting the heatsinkand electronic component. Of course, one or more than two fingers may be employed as partoftheconnection means with a like number of aligned holesformed in the heatsink.

Referring nowto Figures 17 and 18, shown therein and generallydesignated bythe reference character 610 is a sub-assembly consisting of a heat sink 612, an electronic component 614 and yet another alter nate embodiment cf the alignment device 616 (shown in detail in Figures 19 and 20); and a printed circuit board 618. In the illustrated embodiment of the invention, the electronic componenttakes the form of a transistor having three downwardly extending pin connectors 615. Alignment device 616 includes a body 620 (also shown in detail in Figures 21 and 22) defining top surface 622 and bottom surface 624 and is formed from electrically insulating material as previously described.

Meansareformed on the bodyforreleasablyconnecting the heat sink to the alignment device which, in the illustrated embodiment, includes three upwardly projecting spaced tabs 626,628 and 630. The tabs are located in an alternating arrangement re- ceive the heat sink betweentabs 626 and 628 on one side and tab 630 which is located on the other side thereof.

Studs 632 are formed on tabs 626 and 628. Aligned holes 634 are formed in the heat sink. As the heat sink is inserted between tabs 626,628 and 630, the studs are encountered and tabs 626 and 628 are slightly deflected outwardly until holes 634 (shown in Figure 18) are reached. The studs then spring forward to engage the holes and secure the heat sink with the body. The heat sink may be released by deflecting tabs 626 and 628 outwardly to remove the studs from the holes in the heat sink.

On the top surface of the body are formed one or more spacing elements 636 for contacting the lower edge of the heat sink when inserted between the tabs so as to accurately position the heat sink with respect to the top surface ofthe body. On the bottom surface, the body is provided with one or more protuberances 638 to maintain the body a predetermined distance above the surface of the printed circuit board when mounted thereon. The body also includes a suitable number of pin connector holes 640 extending from the top surface to the bottom surface.

Means are provided to securethe electronic com ponent to the heat sink in good thermal contact therewith and to attach the alignment device and heat sinkto the printed circuit board. The attachment and securing means includes attachmentmember 642 (shown in greater detail in Figures 23 and 24).

The attachment member 642 is preferably a unitary body formed from resilient metallic material. A pair of mounting tabs 644 extend laterally and down wardlyfrom eithersideoftheattachmentmember and each includes a portion located in an aligned aperture 646 in the body. The lower ends ofthe mounting tabs are adapted for mounting on preformed locations on the printed circuit board. As shown in Figures 23 and 24,the lowerends ofthe mounting tabs are adapted for insertion and soldering into aligned preformed holes 648 in the printed circuit board. Preferably, the mounting tabs are at least partially coated with a solder-promoting material.

Support members 650 and 652 project upwardly from the top surface of the body and are aligned with and spaced from tab members 626 and 628, respectively. Attachment member 642 is held in place and supported on the body when interposed between the support members and the tabs.

Figure 23A illustrates an alternative embodiment ofthe mounting tabs in which ends 644' ofthe mounting tabs are inserted into preformed holes in the printed circuit board. Each of the mounting tabs includes two fingers 654 which frictionally engage the walls ofthe holes in the printed circuit board. The fingers secure the attachment memberto the printed circuit board until the mounting tabs are permanently soldered in place. Another alternative embodiment is shown in Figure 24Awherein the mounting tabs are adapted for attachmentto the surface ofthe printed circuit board by soldering.The ends ofthe mounting tabs 644" each include a surface 656 disposed parallel with the surface of the printed circuit board and adapted for soldering to preformed mounting pads or areas on the printed circuit board.

The surface 656 may be formed, for instance, by inserting the mounting tabs through the preformed holes in the body and then bending the lowermost ends ofthetabs approximately 900.

The attachment 642 member also includes upwardly extending clip 658. The clip is positioned on the attachment memberfor contact with the elec- tronic component after the alignment device is connected to the heat sink. The electronic component is inserted between the heat sink and the clip with the pin connectors 615 of the electronic component extending through the preformed holes 640 in the body 620 and into the preformed holes 641 in the printed circuit board. The clip acts to urge the electronic component into intimate thermal contact with the heat sink and to secure the electronic component in the desired position when mounted on the printed circuit board, obviating the need for a rivet or screw as in Figures 1 and 2.Thus, the attachment member combines the solderable attachment means and the securing means into a unitary structure. Alternatively, the clip portion of the attachment member may be omitted, if desired, and the electronic component secured to the heat sink in a conventional manner.

Figure 25 illustrates an alternate embodiment 610' ofthe embodiment shown in Figures 17 and 18. It is frequently advantageous to connect two or more el ectronic components to the same heat sink to conserve surface space on the printed circuit board and to reduce material and manufacturing costs. In Figure 25, the body 620' of the alignment device extends beyond both sides ofthe heat sink. A second pair of spaced apertures (not shown) are formed on the body, separated from the first pair of apertures 646 by the heat sink. A second attachment member 672 substantially identical to attachment member 642 is located on the opposite side of the heat sink with a pair of laterally and downwardly extending mounting tabs (not shown) extending through aligned apertures (not shown) in the body.Alternatively, the attachment member may be formed with a unitary U-shaped body (not shown) having two opposing upwardly extending mounting tabs, as in the embodiment in Figure 17, in place of the two sep arate attachment members shown in Figure 25. The mounting tabs are each mounted on preformed locations on the printed circuit board.

Clip support members 678 (only one ofwhich is shown in Figure 25) support attachment member 672 and secure it in place on the body. A second pair of tabs 680 (only one of which is shown in Figure 25) extend upwardlyfrom the top surface ofthe body.

Thetabs 680 are each alignedwith one oftabs626 and 628 and define a slottherebetween for receiving the heat sink. In this embodiment intermediate tab 630, as in Figures 21 and 22, is omitted. Studs 682 are formed on the tabs 680 and are adapted for engage mentwith aligned holes 634 in the heat sink. A second electronic component 684 is secured to the opposite side ofthe heat sink by the clip 686 on the second attachment member 672 with the pin con necto rs 674 fro m the electronic component extending through aligned holes 670 in the body into aligned preformed holes 676 in the printed circuit board. In all other respects the alignment and securing device functions are as hereinabove described.

Referring now to Figures 26 and 27, shown therein and generally designated by the reference character 710 is a sub-assembly consisting of a heat sink712, an electronic device package 714 and anotheralter nateembodimentofthealignmentdevice7l6 (shown in detail in Figures 28 and 29); and a printed circuit board 718. In the illustrated embodiment of the invention, the electronic component takes the form of a transistor having three downwardly extending pin connectors 720. Alignment device 716 includes a body 722 defining top surface 724 and bottom surface 726 and is formed of electrically insulating material as previously described.On the bottom surface 726, the body is provided with one or more protuberances 728to maintain the body a predetermined distanceabovethesurfaceofthe printed circuit board when mounted thereon. The body also includes a suitable number of pin connector holes 732 ex tending from the top surface to the bottom surface.

Means are provided to securetheelectroniccom- ponentto the heat sink in good thermal contact therewith and to attach the alignment device and heat sink to the printed circuit board. The attachment and securing means includes attachment member 734. The attachment member 734 is preferably a unitary body formed from resilient metallic material. A pair of mounting tabs 736 extend laterally and down wardlyfrom either side of the attachment member and each includes a portion located in a slot 738 in either end of the body. The lower ends of the mounting tabs are adapted for mounting with the printed circuit board. As shown in Figures 26 and 27, the lower ends of the mounting tabs are adapted for insertion and soldering into aligned preformed holes 740 in the printed circuit board.Preferably, the mounting tabs are at least partially coated with a solder-promoting coating.

Support members 724 and 744 project upwardly from the top surface of the body. Attachment member 734 is held in place and supported on the bodywhen interposed aboutthe support members with the mounting tabs inserted in the slots as shown.

The attachment member also includes upwardly extending clip 746. The clip is positioned on the attachment memberfor contact with the electronic component after the alignment device is connected to the heat sink. The electronic component is inserted between the heat sink and the clip with the pin connectors 720 ofthe electronic component extending through the preformed holes 732 in the body 722 and into the preformed holes 748 in the printed circuit board for connection by soldering. Alternatively, the connector pins and the mounting tabs may be surface soldered to the printed circuit board as previously described.The clip acts to resiliently urge the electronic component into intimate thermal contact with the heat sink and to secure the electronic component in the desired position when mounted on the printed circuit board, obviating the need for a rivet or screw as in Figures 1 and 2.

Means are provided to releaseably connect the alignment device to the heat sink. In the embodiment of Figures 26-29, the connection means takes the form of a pair of laterally spaced arms 750 integrally formed on attachment member 734. Each arm inclu des triangular head portion 752 divided by slot 754.

As the heat sink is brought adjacent the alignment device, the arms are inserted through aligned holes 756 in the heat sink. As the arms pass through the holes, the head portions are compressed across slots 754, but the head resiliently returns to a relaxed state (as shown in Figure 27) locking the heat sink and alignment device together with the electronic component secured to the heat sink by clip 746. The heat sink may be detached by manually compressing the head portions and withdrawing the arms from the holes in the heat sink. If desired, one, two or more arms as herein above described may be employed as partoftheconnection meanswith a like number of aligned holes formed in the heat sink.

Although the invention has been described above with particular reference to preferred embodiments thereof, these are advanced for illustrative purposes only and are not intended to limitthe scope of the invention as defined by the appended claims. For instance, it is within the scope of this invention that the pin connectors of an electronic component orthe solderable attachment means may either be soldered into preformed holes in the printed circuit board or surface soldered onto preformed mounting pads on the printed circuit board, both of which are encompassed bytheterm "mounting on a preformed location on the printed circuit board," as discussed herein.

Claims

1. An alignment device for use in connecting to a printed circuit board a heat sink and an electronic component package having pin connectors, the device comprising an electrically insulating body having a plurality of holes extending through said body for receiving, aligning and retaining the pin connectors, means for mounting the body on the printed circuit board with the pin connectors accurately positioned with respect to the printed circuit board, and with the heat sink carried by the body and in heat exchange contact with the package.

2. An alignment device for use in connecting to a printed circuit board a heat sink and an electronic component package having pin connectors, the device comprising an electrically insulating body having a number of holes extending through it for receiving, aligning, and retaining the pin connectors, the body being arranged to be mounted in predetermined relation to the printed circuit board with the pin connector accurately positioned with respect to the printed circuit board, and with the heat sink carried bythe body and in heat exchange contact with the package, including means on the body for making positive engagementwith the heatsink.

3. An alignment device for use in connecting to a printed circuit board a heat sink and an electronic component package having pin connectors, the device comprising an electrically insulating body having a number of holes extending through itforreceiving, aligning, and retaining the pin connectors, the body being arranged to be mounted in predetermined relation to the printed circuit board with the pin connectors accurately positioned with respectto the printed circuit board, and with the heat sink carried bythe body and in heat exchange contact with the package, including engagement means between the body and the package.

4. A device as claimed in any preceding claim which includes connection means for releasably connecting said bodyto the heat sink.

5. A device as claimed in any preceding claim in which the body is arranged to be attached in relation to the printed circuit board by solderable attachment means.

6. A device as claimed in Claim 5, wherein said solderable attachment means further includes an attachment member having at least one solderable mounting tab extending through said bodyfor mounting on the printed circuit board.

7. A device as claimed in Claim 5, wherein said solderable attachment means further includes secur ing means adapted for securing the electronic com ponent to the heat sink.

8. A device as claimed in Claim 7, wherein said securing means comprises a clip adapted for resiliently urging the electronic component package into thermal contact with the heat sink.

9. A device as claimed in Claim 1 to 7, wherein the heat sink is arranged, when mounted on the body, to be substantially parallel with the surface ofthe printed circuit board.

10. A device as claimed in any preceding claim in which the body is arranged to be connected to the heat sink by connection means which comprises at least one arm extending from said body and adapted to engage an aligned hole in the heat sink.

11. A device as claimed in any preceding claim including attachment means having a surface having a solder-promoting coating and disposed parallel to the surface ofthe printed circuit board when said body is adjacentthereto for mounting the body at a predetermined location on the surface of the printed circuit board.

12. A device as claimed in any of Claims 5 to 10 wherein said solderable attachment means includes at least one portion having a solder-promoting coating which is adapted for insertion into a preformed hole in the printed circuit board and soldering therewithin so as to mount said solderable attachment means in said body on a predetermined location on the surface of the printed circuit board.

13. A device as claimed in any of Claims 5 to 12 including solderable attachment lugs moulded into said body.

14. A device as claimed in any preceding claim in which the body has top and bottom surfaces through which said holes extend and includes spaced tab means projecting upwardly from said top surface for releasably connecting the body to the heat sink.

15. A device as claimed in Claim 14 wherein said tab means includesa pairoftabmemberswithone of said tab members arranged to engage the electronic component and the other arranged to engage the heat sink.

16. A device as claimed in claim 15 wherein said one tab member has a ledge projecting toward said other tab member for engaging a top surface on the electronic component; and said other tab member includes a stud projecting toward said one tab memberfor insertion in a hole in the heat sink.

17. A device as claimed in Claim 14wherein said tab means includes spaced tab members projecting from said top surface, each tab member having a slot therein for receiving the heat sink.

18. A device as claimed in Claim 14 wherein said tab means includes three tab members projecting from said top surface and located in alternative positions defining a spacetherebetweenforreceivingthe heat sink.

19. AdeviceasclaimedinClaim l8whereinthe centre of one of said tab members has a stud located thereon projecting toward the othertab members for engaging a hole in the heat sink.

20. A device as claimed in any of Claims 1 to 3 including a resilient clip adapted for contact with the electronic component so as to securethe electronic component to the heat sink.

21. A device as claimed in claim 20 in which the resilient clip has tabs leading through the body for fastening to the printer circuit board.

22. A device as claimed in Claim 20 or Claim 21 in which the resilient clip has lugs for engagement with the heat sink.

23. A device as claimed in any precedign claim in which the body is formed with projections for spacing the body from the printed circuit board.

24. A device as claimed in any preceding claim in which the body has a pair of opposed surfaces, one arranged to face the printed circuit board and the other arranged to receive the heat sink.

25. A device as claimed in claim 24 including bolt means for holding the heat sink, the package, the body and the printed circuit board together.

26. A mounting device constructed and arranged substantially as the electrically insulating body specifically described with reference to Figures Sand 6,or7,or8,orll and 12, or 15 and 16, or 19 and 20, or 28 and 19 of the accompanying drawings.

27. An assembly of an electronic component package, a heat sink, and a printed circuit board, held in location by an alignment device as claimed in any ofthe preceding claims.

28. A method of mounting an electronic component package and a heat sink on a printed circuit board, in which the package and sink are mounted on an alignment device as claimed in any of Claims 1 to 26, with the pin connections on the package aligned in the holes in the body, and the body is then mounted on, and secured to, the printed circuit board, and the pin connections are connected to the printed circuit board.